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Effect of hydro-compacting organic mulch on weed control and crop performance in the cultivation of three container-grown ornamental shrubs: Old solutions meet new insights
... In Figure 3, the separated pivot nodes at different time slices show that the studies on nursery/container weed control, fertilizers, and herbicides are not well connected. The literature was widely distributed based on various topics, such as weed control methods (herbicide, fertilization, and mulch) as well as crops (pine trees, peaches, and ornamentals), indicated by the scattered pivot nodes (Hanson and Schneider, 2008;Brosnan et al., 2012;Altland et al., 2016;Stewart et al., 2018;Massa et al., 2019;Saha et al., 2019a). ...
... Later, mulches stood out among other non-chemical practices and became a research hot spot due to their easy availability and low prices (Chalker-Scott, 2007). The widely tested mulches, such as pine bark, rice hull, Douglas fir bark, coconut coir, newspaper pellets, and waste paper (Pellett and Heleba, 1995;Penny and Neal, 2003;Amoroso et al., 2009;Mathers and Case, 2010;Chen et al., 2013;Marble, 2015;Bartley et al., 2017;Burrows, 2017;Masilamany et al., 2017;Marble et al., 2019;Massa et al., 2019). Adding mulches (2.54-7.62 cm) can reach satisfactory weed control results depending on mulch types and weed species (Richardson et al., 2008;Cochran et al., 2009;Altland et al., 2016;Massa et al., 2019;Särkkä and Tahvonen, 2020). ...
... The widely tested mulches, such as pine bark, rice hull, Douglas fir bark, coconut coir, newspaper pellets, and waste paper (Pellett and Heleba, 1995;Penny and Neal, 2003;Amoroso et al., 2009;Mathers and Case, 2010;Chen et al., 2013;Marble, 2015;Bartley et al., 2017;Burrows, 2017;Masilamany et al., 2017;Marble et al., 2019;Massa et al., 2019). Adding mulches (2.54-7.62 cm) can reach satisfactory weed control results depending on mulch types and weed species (Richardson et al., 2008;Cochran et al., 2009;Altland et al., 2016;Massa et al., 2019;Särkkä and Tahvonen, 2020). In addition, innovative non-chemical weed control methods, such as fertilizer placement, irrigation, flaming, steaming, oil palm, real-time robotics have been proposed and tested (Rainbolt et al., 2013;Frasconi et al., 2014;Masilamany et al., 2017;Pokharel et al., 2017;Stewart et al., 2017Stewart et al., , 2018Saha et al., 2019b;Raja et al., 2020). ...
Weeds, as one of the biggest challenges in the nursery industry, have been controlled by various methods, such as chemical and non-chemical practices. Although these practices have been widely established and tested to control weeds, there is no systematic or meta-analysis review to provide quantitative weed control efficacy information of these practices. To provide a systematic understanding of weed control practices in nursery production, a visualization research trend, a systematic review, and a meta-analysis were conducted. A total of 267 relevant studies were included for the research trend and 83 were included in the meta-analysis. The results in this study showed that interests in nursery weed control have switched dramatically in the past 2–3 decades (1995–2021) from chemical dominant weed control to chemical coexistent with non-chemical techniques. Developing new management tactics and implementing diverse combinations of integrated weed management present the future trend for weed control. The systematic review results showed that chemical methods had the highest weed control efficacy, while non-chemical had the lowest on average, nonetheless, all three weed control practices (chemical, non-chemical, and combined) reduced the weed biomass and density significantly compared with when no strategy was employed. Weed control challenges could be the catalyst for the development of new non-chemical and integrated weed control techniques.
... No negative effects were observed on hydrangea plant health as no difference was found between treated containers and a bare substrate control. Massa et al. (2019) did not report cracking in the film surface, but they found that weed suppressive abilities were lost after the film degraded 10 months after transplanting. ...
... Giaccone et al. (2018) found that a chitosan-based sprayable mulch film successfully reduced weed biomass relative to a non-treated control for two months before it began to degrade with no negative effects measured on desired ornamentals. Massa et al. (2019) found that liquid mulch reduced weed biomass by 74% relative to an untreated control while the dry weight of selected plants was increased compared to the control. In GH Trial 1, velvetleaf was also successfully reduced relative to a non-treated control, but crop plant biomass was reduced from a non-treated, weed-free control and even non-treated, weedy controls when applied at higher rates as plants were unable to withstand the solution application, indicating that the solution caused more damage than to weeds alone. ...
... The removal of excess water along with a 25% increase in the concentration of corn starch in the formulation compared to that used in Field Trial 3 was enough to increase the viscosity to an effective level while still ensuring it could be applied as a (2018) reported that dry biomass was lower in sprayable mulch treated plots relative to a bare soil control and a herbicide treated plot. However, in Field Trial 4, kale yields were not increased in treated plots relative to a non-treated, weedy control, which was not the case for Massa et al. (2019) who found dry biomass of test plants to be improved from an untreated control. Giaccone et al. (2018) reported no difference in dry biomass between treated and untreated containers. ...
A sprayable bio-based mulch film (biofilm) could present a more sustainable weed management tool for specialty crop producers than conventional plastic mulch films while also offering flexibility in application patterns and timing. From 2017 to 2019, six greenhouse trials and four field trials were conducted at the University of Nebraska-Lincoln to study the effects of biofilm application on weed suppression and crop yields. Multiple application rates (0.81 L/m2 - 9.78 L/m2) and application times (prior to weed emergence and post weed emergence) were tested. Corn starch, glycerol, keratin hydrolysate, corn gluten meal, corn zein, and isolated soy protein were evaluated as potential ingredients due to their ability to form biodegradable films or suppress weed growth as reported in other research. The efficacy of weed control displayed by biofilm solutions ranged from a promotion of weed biomass to 100% reductions relative to a non-treated, weedy control. The wide range of results was most likely attributable to solution viscosity: a greater efficacy of weed control was displayed when the viscosity was increased as this allowed a more cohesive layer to form on the soil surface. The most promising mulch film was displayed in the final field trial, to which biomass was reduced by greater than 97% when applied prior to weed emergence and by greater than 94% when applied post weed emergence. However, despite these findings, crop yields were not improved relative to a non-treated, weedy control in any of the field trials. Variables such as solution salinity and C:N ratio could play a role and need to be evaluated in future research trials. Advisors: Sam Wortman and Sibel Irmak
... Biodegradable mulching films can be created using natural or synthetic polymers like starch, polylactic acid, or polyvinyl acid (Vox et al., 2013). On the other hand, biodegradable mulching sprays can be formulated using water-based solutions of natural polysaccharides such as sodium alginate, galactomannan, chitosan, and cellulose (Schettini et al., 2007;Immirzi et al., 2009;Massa et al., 2019). While this is a new area of research, there have been promising results. ...
... A similar problem mentioned above by Shen and Zheng, 2017 was also reported in this study, the recycled paper slurry in the container began to shrink at 3 months, and with higher rainfall, it started to break down at a faster rate (Figure 3). In a study conducted by Massa et al., 2019, the efficacy of weed control was evaluated for a hydro-compacting organic mulch made from organic fibers sourced from Hibiscus cannabinus L., combined with a polyvinyl alcohol-based adhesive. This mulch type was compared against alternative organic mulches and herbicide treatments. ...
Weed management in container plant production is a serious problem and remains one of the most expensive and time-consuming aspects of the industry. Weeds cause severe reductions in crop growth due to the limited growing environment characteristic of container plant production. The container nursery industry relies heavily on a limited number of preemergence herbicide options. The use of herbicides as the primary means to manage weeds has resulted in some negative consequences such as high chemical costs, leaching, runoff, and concerns with recycling irrigation water. Additionally, nursery growers are shifting their focus toward different nonchemical weed management strategies because many ornamental plants are very sensitive to preemergence herbicides. One such method is using organic mulch to control weeds in container plant production. Mulching is the foundation of a nonchemical weed management protocol and acts as the first line of defense against weeds. Organic mulches used in container plant production include rice hulls, pine bark, wood chips, wood shavings, coconut coir, nut (peanut, pecan) shells, oyster shells, cacao bean hulls, pelletized newspaper, recycled newspaper, pine straw, and other materials; material selection often depends on the availability of the product. The objective of this manuscript is to provide a comprehensive review of existing research on the utilization of various mulch materials as a weed management tool in container plant production. Additionally, it aims to highlight any critical knowledge gaps and provide suggestions for possible future research.
... Weed suppression ranged from 93.8% ± 6.3% at the lowest rate (0.9 LÁm À2 ) to 100% at rates of 4.5 LÁm À2 or more. Previous studies have demonstrated the potential for BSM films to reduce weed biomass and infestation by %70% to 85% [primarily sowthistle (Sonchus sp.)] (Giaccone et al. 2018;Massa et al. 2019), but the level of suppression (>93%) at rates as low as 0.9 LÁm À2 observed here exceeded expectations. ...
... Claramunt et al. (2020) reported a weed seedling reduction of 85% to 93% for redroot pigweed (Amaranthus retroflexus), large crabgrass (Digitaria sanguinalis), prickly lettuce (Lactuca serriola), and common sowthistle (Soncha oleraceus). Massa et al. (2019) reported a reduction of 74% in weed biomass (primarily common sowthistle) and a dry weight increase of 11% in Japanese camellia (Camellia japonica). Measured benefits will vary greatly depending on environmental conditions and the species and density of the weed populations. ...
Biobased sprayable mulch (BSM) films are a potential alternative to herbicides, polyethylene plastic mulch film, and hand weeding for specialty crops. We developed a series of BSM films using locally available biomaterials [including corn ( Zea mays ) starch, glycerol, keratin hydrolysate, corn gluten meal, corn zein, eggshells, and isolated soy ( Glycine max ) protein] and tested their effects on weeds and crop yield during a total of seven greenhouse or field trials between 2017 and 2019 in Nebraska, USA. Application rates of BSM films applied in pots (greenhouse), planting holes in plastic film (field), or bed tops (field) ranged from 0.9 to 18.2 L⋅m ⁻² ; they were applied before and after the emergence of weeds. Weed control efficacy was variable, and results of greenhouse pots were rarely replicated under field conditions. Increasing the viscosity of the final suspension tested [BSM7; a mix of corn starch (72.8 g⋅L ⁻¹ ), glycerol (184.7 mL⋅L ⁻¹ ), keratin hydrolysate (733.3 mL⋅L ⁻¹ ), corn zein (19.8 g⋅L ⁻¹ ), and isolated soy protein (19.8 g⋅L ⁻¹ )] reduced weed biomass by more than 96% in field-grown kale ( Brassica oleracea var. sabellica ) when applied to bare soil bed tops before or after weed emergence, but kale yield in treated plots was not different from the weedy control. The results demonstrated the potential for postemergence applications of BSM films, which increase application timing flexibility for growers. Further research is needed to explore the effects of BSM films on soil properties and crop physiology and yield.
... The effects of mulch vary depending on the type of mulch material used, therefore, standardization of mulch materials is very important for better growth and optimal performance of plants (Daniele et al., 2019). Despite the positive effects of organic mulches such as weed control, moisture and temperature amelioration and water-saving (Daniele et al., 2019), these materials might, in some cases, be sources for allelopathic effects. ...
... The effects of mulch vary depending on the type of mulch material used, therefore, standardization of mulch materials is very important for better growth and optimal performance of plants (Daniele et al., 2019). Despite the positive effects of organic mulches such as weed control, moisture and temperature amelioration and water-saving (Daniele et al., 2019), these materials might, in some cases, be sources for allelopathic effects. Such effects may hinder the germination and growth of landscape plants adjacent to or combined with them. ...
Mulches have significant environmental, aesthetic and functional benefits. However, there are arguments that some organic types of mulches prevent seed germination and the growth of plants due to their allelopathic effects. This study examined the allelopathic influence of the extracts of some organic mulches on seed germination percentage, and growth of the seedlings of some ornamental plants in two interrelated experiments. In the first experiment , allelopathic effects of six organic mulches including pine wood chips of the plane tree, pine cones, pine leaves, pine barks, sawdust, and grass clippings of Festuca arundincea were examined on germination and early growth of lettuce seeds as an indicator species. The second experiment was designed based on the results of the first experiment so that the extracts of the mulches with the lowest germination rates were selected and their effect on seed germination of five flowering plants of Alyssum maritimum, Celosia argentea, Tagetes sp., Zinnia sp. and Rudbeckia sp. were evaluated. The results showed that pine leave extracts had inhibitory effects on germination of lettuce seeds (in the first experiment) and also showed significant and strong inhibitory effects (P<0.01) on seed germination, radicle length, plumule length, plumule fresh and dry weights of all seasonal flowers. Based on these results, pine leaves after being released in the soil or after decomposition may act as a source of allelochemicals and should be used by care as mulch in landscaping at least if it is combined with ornamental plants.
... Various other studies have reported the importance of organic mulches for weed suppression and improvement of ornamental plant growth. Ref. [26] analyzed a hydrocompacting organic fiber mulch in containerized production and found that it reduced weed presence by 70% and improved the plant performance of camellia (Camellia japonica), cupressus (Cupressus sempervirens), and photinia (Photinia fraser 'Red Robin'). Rice husk mat applied at 8 mm depth can be used for weed control in nursery polybags as it helps to reduce the coverage, emergence, and biomass of Cyperus distans, Ageratum conyzoides, and Eleusine indica weeds [27]. ...
Liverwort (Marchantia polymorpha) competes for resources within containers, resulting in a reduction in the quality and market value of ornamentals. Therefore, the objective of this study was (1) to assess the impact of different mulch types, depths, and their moisture-holding-capacity on liverwort control and (2) to quantify if phytotoxicities develop on ornamental plants due to the mulches. The percent water retention of four different organic mulches [rice hull (RH), cocoa hull (CH), pine bark (PB), or red hardwood (HW)] was determined in a laboratory experiment. In a greenhouse experiment, the Hosta plantaginea (Plantain Lily) varieties ‘Curly Fries’ and ‘Pandora’s Box’ were mulched with either RH, HW, CH, or PB at a depth of 0.63, 1.27, 2.54, or 5.08 cm. Liverwort thalli coverage on the container surface was visually estimated bi-weekly, and the fresh weight of the thalli was recorded at the end of the experiment. The results indicated that CH mulch retained the highest amount of moisture (86%). The RH and HW mulches, at depths of 1.27 cm or more, provided excellent (>80%) liverwort control in ‘Curly Fries’. All mulches at depths of 1.27 cm or more showed excellent (100%) liverwort control for ‘Pandora’s Box’. Overall, RH and PB mulches at all depths provided excellent liverwort control and no reduction in the growth of ‘Curly Fries’ and ‘Pandora’s Box’.
... The significant interaction between mulching and variety that led to SAMNUT 26 producing higher kernel yields in both locations with black polythene and transparent polythene mulch could be attributed to the successful weed suppression attained by the mulching types, which allow the SAMNUT 26 variety to utilize the available moisture conserved for optimum dry matter production. According to studies by Sathyamurthy et al. (2017), Massa et al. (2019) and Iqbal et al. (2020), mulch plots boosted plant productivity by suppressing weed growth. ...
In order to increase groundnut productivity, a field experiment was carried out in the dry season of 2020 to assess the effectiveness of various mulching materials at suppressing weeds. The experimental treatments comprised of five mulching types; Control (no mulch), transparent polythene mulch, black polythene mulch, rice straw mulch and saw dust mulch) and three groundnut varieties (SAMNUT 23, SAMNUT 24 and SAMNUT 26). These were factorially combined and laid out in a Randomized complete block design with three replications. Findings revealed that mulching had a significant (p < 0.05) impact on crop qualities including canopy cover, chlorophyll content, pod yield, 100 kernel weight, and groundnut kernel yield as well as weed attributes like weed cover scores, weed density, weed dry weight, and weed control efficiency in both BUK and Wasai, respectively. The weed compositions were further grouped into various families comprising Poaceae (11), Euphorbiaceae (3), Amaranthaceae (4), Asteraceae (3), Cyperaceae (2), Cucurbitaceae, and Aizoaceae, each having one species with a different level of occurrence across the two locations. On the other hand, SAMNUT 26 significantly produced higher pod (2798 & 2119) and kernel yields (1198 & 1191), although SAMNUT 23 produced a heavier 100 kernel weight (55.51 & 54.52) at BUK and Wasai, respectively. In comparison to the other mulching types, applying black polythene mulch or transparent mulch lowered weed density and dry weight by limiting the amount of sunlight that the weeds got, preventing them from growing. Therefore, for dry season production of groundnut in the Sudan savannah ecology of Nigeria, mulching with black or transparent polythene film using the SAMNUT 26 variety was found to be effective in conserving soil moisture for optimum crop growth and development, while on the other hand, weed populations were suppressed.
... Britton & Rose (Fabaceae) is widely employed [9][10][11][12]. However, grass management is primarily conducted through chemical control [13,14], which can lead to resurgence before the target species are established [15]. In these systems, fertilization practices can influence the competition dynamics between natives and invaders by altering soil fertility [16,17]. ...
To restore invaded areas, planting fast-growing native species such as Senegalia polyphylla (DC.) Britton & Rose (Fabaceae) is widely used. However, invasive grasses reduce light availability, alter fire regimes, and compete for water and nutrients, hindering the growth of native trees. Fertilization practices influence the competition dynamics between natives and invasives by altering soil fertility. Therefore, this study investigated the effects of mineral and organic fertilization on the nutritional status and growth of S. polyphylla cultivated during the first 120 days after transplanting. The experiment was conducted in a completely randomized design comprising five treatments and four replications, along with the unfertilized control (0–0%) as an additional treatment. Dystrophic red latosol and different proportions of mineral and organic fertilizers were used. The variables evaluated included dry mass of aboveground parts and roots, nutrient content in leaves, and nutrient use efficiency. The results showed that fertilizations with high nutrient concentrations (100–0% and 75–25%) resulted in greater accumulation of N, P, and K in the leaves, while balanced fertilization (50–50% and 25–75%) led to greater root dry mass. These results emphasize the importance of strategically choosing fertilizer formulations to promote the healthy development of seedlings in areas subject to interference from invasive grasses.
... mixed with an adhesive made of polyvinyl alcohol and organic fibres. This sticky material compacts organic matter into a disc when water is added (Massa et al., 2019). It successfully stops sunlight from penetrating and stops weeds from emerging. ...
Organic mulches can suppress annual weeds and offer other important benefits, such as organic matter, nutrients, moisture conservation, soil protection, and moderation of soil temperature. Drawbacks include costs and labor of application, limited efficacy on perennial weeds, delayed soil warming, and the potential to carry weed seeds and harbor pests.
... Strategic fertilizer placement and mulching are two of the most effective nonchemical tools to manage weeds in container nursery production [16][17][18][19][20][21][22]. Substrate stratification combines these two methods by strategically placing fertilizer only in the bottom stratum and creating a mulch-like layer with the use of coarse particles in the top strata [10]. ...
The objective of this study was to determine how topdressing or incorporating fertilizer with stratified or mulched substrates could affect the growth of Hibiscus rosa-sinensis ‘Snow Queen’, a popular ornamental plant, and the growth of liverwort (Marchantia polymorpha) and bittercress (Cardamine flexuosa), two common nursery weed species. Five different substrate treatments were evaluated, which included three stratified substrates composed of pine bark screened to a small (0.63–1.27 cm), medium (≤1.90 cm), and large (0.96–1.90 cm) particle size and two industry-standard substrates that were either mulched with rice hulls or remained unmulched. All treatments were then fertilized via either topdressing or incorporating a controlled-release fertilizer (CRF). Bittercress control was highest in mulched containers, followed by those stratified using the medium pine bark, and its growth increased overall in topdressed vs. incorporated containers regardless of substrate or mulch treatment. All the stratification treatments resulted in a decrease in liverwort coverage compared to the industry standard treatment, but topdressing generally increased liverwort coverage compared with incorporating fertilizer. In conclusion, both topdressing and incorporation appear to be compatible with fertilizer placement methods with substrate stratification from a crop production standpoint; however, weed growth may increase if fertilizer is topdressed.
... Plants may absorb and detoxify a variety of toxins, including heavy metals, organic pollutants, and radionuclides, through mechanisms such as phytoextraction, phytostabilization, and phytodegradation (Lee, J. H. 2013). Moreover, through phytoremediation and phyto-monitoring, plants can enhance air quality by eliminating contaminants from the environment (Massa, D., et al., 2019). Furthermore efficient at cleaning wastewater and eliminating toxins from water, wetland plant, and microbial systems (Vymazal, 2018). ...
Plants and plant-microbial compounds can be a viable means of remediating contaminated soils, in this review, two approaches to phytoremediation are discussed, the first approach how plants can promote the growth of degrading microorganisms in the soil rhizosphere, which can lead to enhanced degradation of chlorinated pesticides; the second approach focuses on the potential of plants to remove and accumulate metals from their environment, a unique test system, the Target Neighbor Method, is used to evaluate how plant density affects metal uptake, these studies could provide valuable information for optimizing plant density to improve metal removal and remediate metal-contaminated soils or to minimize toxic metal accumulation in crops and reduce human exposure.
... In recent years, researchers have again been exploring using nonchemical or integrated weed control methods for weed control (Giaccone et al., 2018;Masilamany et al., 2017;Shen and Zheng, 2017;Somireddy, 2011;Witcher and Poudel, 2020). Some of the most widely evaluated mulch materials have included pine (Pinus sp.) bark, rice (Oryza sativa) hulls, Douglas fir (Pseudotsuga menziesii) bark, coconut (Cocos nucifera) coir, newspaper pellets, and wastepaper (Bartley et al., 2017;Burrows, 2017;Marble, 2015;Marble et al., 2019;Masilamany et al., 2017;Massa et al., 2019;Mathers and Case, 2010). Richardson et al. (2008) reported that applying 3 inches of pine bark mini-nuggets controlled hairy bittercress (Cardamine hirsuta) in large (3-7 gal) containers up to 150 d. ...
Pennsylvania bittercress ( Cardamine pensylvanica ) and other bittercress ( Cardamine ) species are among the most common and difficult-to-control weed species in container nurseries, and they have been vouched in most counties in Florida. Preemergence herbicides can provide control, but concerns over potential resistance development, environmental issues, and crop injury problems associated with herbicide use create the need for alternative weed control methods to be explored. Previous studies have shown the potential of mulch materials for controlling weeds in nurseries, but their use along with preemergence herbicides has not been extensively investigated. To compare the effects of different mulch materials and herbicides on Pennsylvania bittercress control, a full factorial designed greenhouse study was conducted. Three mulch treatments including no mulch, pine ( Pinus sp.) bark, and rice ( Oryza sativa ) hulls were evaluated with three herbicide treatments, including water (i.e., no herbicide), isoxaben, and prodiamine applied at label rates. Twenty-five seeds of Pennsylvania bittercress were sown on the surface of each container and emergence (percent), coverage (square centimeters), seedhead number, and biomass (grams) were measured. The results showed that Pennsylvania bittercress in containers mulched with rice hulls had the lowest emergence throughout the experiment. For coverage, seedhead, and biomass parameters, Pennsylvania bittercress seeded in rice hulls treatments had significantly lower coverage, fewer seedheads, and lower biomass compared with those in nonmulched or pine bark treatments, regardless of herbicide treatment. With isoxaben and the water check, nonmulched treatments had the highest coverage/seedhead/biomass, whereas with prodiamine, Pennsylvania bittercress in pine bark mulched containers had the highest coverage/seedhead/biomass. In conclusion, applying rice hulls alone can provide better Pennsylvania bittercress control compared with isoxaben or prodiamine applied alone.
... They are inexpensive and eco-friendly and adding nutrients to the soil (Kader et al., 2019). Furthermore, these mulches enhance germination by almost upto 70% while decreasing soil erosion upto 30% (Massa et al., 2019;Shojaei et al., 2019). ...
Drought, salinity, temperature extremes, and heavy metals are the major environmental factors that limit sustainable crop production worldwide and consequently restrict crop yield. There is a dire need for environment-friendly agricultural practices to achieve long-term food production for the growing population. Mulching has become a common method in modern agricultural practices because of its numerous benefits, such as moisture conservation, augmentation temperature of the soil, reduction of insect pests, weed management, escalation of crop yield, and the effective use of nutrients present in the soil, as well as decreased soil salinity. Mulching also enhances plants’ resistance to pests and diseases and various stress factors like heat, salinity, drought, metals, and high or low temperatures. In addition to this, mulches could also provide economic, aesthetic, and other ecological benefits to agriculture. Mulching markedly increased the growth, yield, nutrient use, and water use efficiency in crop plants under stressed and non-stressed conditions. As a result, future research could also focus on economic, environment friendly, and, more importantly, biodegradable materials on plant growth, balanced nutrition, yield, and quality under various abiotic stress conditions. This chapter focuses on the many essential aspects of mulches on the productivity and establishment of multiple crops under stressful environments.
... Thus, a controlled environment is more preferred to cultivate vegetables like Chinese cabbage. Development of conventional system like soil drip irrigation which combine with plastic mulch has a better condition to keep the soil moisture, reduction of weeds, and improve the quality of the final product [10], [11]. Meanwhile, vertical farming like hydroponics, considered as a highly productive, suitable for urban areas, and can address the shortage of land in demand for food production [2], [12]. ...
The quality of vegetables is determined by many factors such as texture, flavor, chromaticity, and health-beneficial metabolites. Chinese cabbage is one of the most commonly consumed vegetables in Western and Asian and countries including Korea. Change in firmness of Chinese cabbage leaf tissues has not been comprehensively studied, although it serves as an important quality indicator of this product. The objective of this study was to characterize textural parameters of Chinese cabbage and to compare them in different cultivars and cultivation practices (soil fertigation or hydroponics). Soluble sugar content, leaf thickness, and chromaticity were higher in plants grown via hydroponics than in those grown via fertigation. Meanwhile, firmness and dry mass of midrib tissues showed an opposite trend in all tested cultivars. Additionally, starch contents and cell wall compounds (i.e., polyuronides and non-cellulosic neutral sugars) of midrib tissues were detected higher in plants grown via fertigation than in those grown via hydroponics. Moreover, the amounts of starch, cell wall compounds, and neutral sugars showed a positive correlation with the firmness of Chinese cabbage leaf tissues. Taken together, these data provide an informative insight for improving cultivation practices, particularly hydroponics of Chinese cabbage plants.
... Shive et al. (2017) showed that in addition to increasing germination (95% from 2013 to 2014), mulch also reduces erosion in damaged areas in California. Organic mulches (straw mulch, biochar mulch, and living plant material) have been shown to play an important role in water conservation and fertility enhancement (Li et al. 2020;Mousavi et al. 2022), as well as decrease soil erosion and increase germination by 30% and 70%, respectively (Massa et al. 2019). In a study in Iran, Katebi et al. (2018) presented laboratory results of a novel mulching liquid that produced a crust to stabilize sand that considerably decreased wind erosion compared to regions with no mulch. ...
The objective of this research was to evaluate various non-petroleum mulches, including resin, mineral, polymer, and biopolymer, on soil properties, plant growth promotion, and sand dune fixation. A field experiment was conducted in the Aran va Bidgol Desert, Central Iran. Three Barchanoid dunes were selected for each mulch treatment and three as the control (15 total). Electrical conductivity (EC), pH, organic matter (OM), phosphorus (P), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), total nitrogen (T-N), sodium absorption ratio (SAR), and exchangeable sodium percentage (ESP) were determined at the beginning and end of the field test. Haloxylon persicum seeds and plants were planted in both a plot and a field to study the effect of mulches on seed germination and plant establishment. Scaled indicators placed in different parts of the dunes were monitored monthly to calculate the fixation effect coefficient, and the amount of sediment and sand removal were recorded. One-way ANOVA results showed that, except for the phosphorus, different mulches had a significant effect on all soil properties. According to the results, resin and polymer mulch improved some of the soil properties (regarding fertility and nutritional status). Considering the salinity and pH of the soil, it is observed that increasing the ESP and SAR of the mineral mulch caused soil salination and alkalization. In general, the findings of this study showed that none of the mulches examined for stabilization of sand dunes were recommended.
... Organic fibers combined with adhesive substance based on polyvinyl alcohol. On adding water, this adhesive substance creates a compacted organic disk (Massa et al., 2019). It effectively blocks sunlight entry and prevents weed emergence. ...
... Various non-chemical weed control methods have been evaluated in disparate cropping systems (Buhler and Gunsolus 1996;Cheema and Khaliq 2000;Héraux et al. 2005;Place et al. 2009;Pannacci et al. 2018;Zangoueinejad et al. 2018). Among all non-chemical weed control tools, the use of organic mulch materials could be an adequate alternative not only because of a long history of their application but also due to their weed repression capability, effectiveness in diminishing the soil erosion as well as temperature fluctuations, usefulness in enriching soils in terms of organic matter contents, and ability in ameliorating the plant growth (Crutchfield et al. 1986;Skroch et al. 1992;Litzow and Pellett 1993;Monks et al. 1997;Ampofo 2018;Gheshm and Brown 2018;Massa et al. 2019;Ainika et al. 2020). Numerous studies have been conducted to investigate the weed control capability of different organic mulch materials compared with various herbicide options (Schonbeck 1999;Wilen et al. 1999;Burkhard et al. 2009;Anzalone et al. 2010;Teame et al. 2017). ...
A field experiment was run in two years to evaluate five organic materials as the potential alternatives for the use of the herbicides to lessen the weed infestation in tomato production. The application rate of corn residues + sawdust (CRSD), rice straw + sawdust (RSSD), wheat straw + sawdust (WSSD), barley straw + sawdust (BSSD), and shredded date palm leaves + sawdust (SDPLSD) as the mulch materials were 8.5, 9.8, 9.3, 9.4, and 8.8 t ha⁻¹, respectively. Based on the results, SDPLSD represented the lowest weed dry matter by 79.1 g m⁻², which was followed by metribuzin, metribuzin + rimsulfuron, WSSD, and BSSD, with recording 114.9, 120.0, 122.6, and 137.0 g m⁻² of weed dry mass, respectively, in 2016. Moreover, SDPLSD indicated the highest level of weed control efficacy (WCE) by 82.7% in 2017. The most total marketable yield (TMY) was observed in the covered plots with SDPLSD, which was 62.1 and 61.9 t ha⁻¹ in 2016 and 2017, respectively. Overall, SDPLSD could be a rational alternative for herbicide options because of its performance in controlling weed invasion as well as enhancing TMY.
... Because they are cheap and environment friendly and add nutrients to soil (Kader et al. 2017(Kader et al. , 2019. Organic mulches improve germination by 70% and reduce erosion by 30% (Massa et al. 2019;Shojaei et al. 2019). ...
In this study, cadmium, copper, nickel, zinc, chromium, manganese and lead were determined in Cladophora fracta present in Lake Hazar (Turkey). The health risks (non-carcinogenic and carcinogenic) of heavy metals associated with the use of Cladophora fracta as mulch were also determined. Bioconcentration factor (BCF) and metal pollution index (MPI) were calculated. When compared with reference value (1.5 mg/kg for Cr and 200 mg/kg for Mn), the highest accumulation by Cladophora fracta was seen in the month of June as 1442 ± 7.2% (23.13 mg/kg) for Cr and the lowest accumulation calculated in the month of July as 5 ± 0.2% (210 mg/kg) for Mn. In our study, the highest MPI value was 13.69 in September. The magnitude of MPI values of heavy metals determined during April to September appeared in the following order September > August > July > June > May > April. The HQing (hazard quotient due to ingestion) and HQinh (hazard quotient due to inhalation) in all months were chidren > female > male while the order of HQder (hazard quotient due to dermal) was determined as male > female > children. Non-carcinogenic risk (HQ) and Hazard Index (HI) values in terms of ingestion, inhalation and dermal ways were lower than 1. Also, total HI values were < 1. As a result, there was not non-carcinogenic and carcinogenic risks associated with usage of Cladophora fracta as mulch.
... Based on the results, 95% of germination was successful from 2013 to 2014 and erosion reached its minimum level in the area (Shive et al., 2017). Organic mulches (once were living plant materials) increase germination to 70% and they decrease soil erosion to 30% (Massa et al., 2019). In a study carried out on the effect of mulch over erosion in Spain, the result presented that organic mulch made with reed plant could decrease erosion considerably compared to regions with no mulch. ...
Wind erosion is considered as one of the most influential factors in the destruction of land in arid and deserted areas. There is a weak ecosystem in arid lands which wind erosion can move soil particles. Mulch is a compound that is used nowadays to control wind erosion. This study aims to create organic mulch in order to prevent wind erosion and environmental pollution. In order to create this type of mulch, different available materials such as blackstrap, manure, biosolids, and straw have been used. Response Surface Methodology (RSM) was applied to create this kind of mulch as well. Also, Central Compound Design (CCD) in RSM modeling was applied to optimize the mulch compound so as to decrease erosion and increase the thickness of crust and its penetration. In addition, each variable was coded and the concentration of straw effect (2-10 g m −2), biosolids (8-24 g m −2), manure (8-24 g m −2) and blackstrap (5-15 g m −2) on wind erosion and penetration were studied. The optimum values of crust thickness (1.5 mm) for straw, manure, blackstrap, and biosolids were 12.48, 19.94, 7.16, and 16.70 g respectively. The optimum values for penetration resistance for straw, manure, blackstrap, and biosolids were 11.31, 15.71, 4.36, 19.24 g as well. As these materials were used more and more in the compound, penetration resistance soared due to adhesion and crust in the compound. However, more use of blackstrap brought about a reverse result. The results indicated that there was not a considerable difference between predicted data and experimental data, and the model was acceptable in simulation.
ATIF/REFERENCE: Sargın, K. F., Akın, B. (2023). Agropyron repens (L.) P. Beauv. Ekstraktlarının Domates ve Bazı Önemli Yabancı Ot Türleri Üzerine Herbisit Etkilerinin Araştırılması. Avrupa Bilim ve Teknoloji Dergisi, (52), 279-288. Öz Araştırmamızda, Agropyron repens (L.) P. Beauv. (ayrık otu)'in bitki kısımlarından hazırlanan ekstraktların domates ve yabancı ot tohumlarının çimlenmesi ve fide gelişimi üzerine etkilerine bakılmıştır. A. repens bitkisinden 25 ℃ (ılık) ve 80 ℃'de (sıcak) farklı günlerde (1-4-7-15-30) bekletilerek ekstraktlar elde edilip, önemli bir kültür bitkisi olan domates tohumları (H-2274, Ege Pembesi, SC-2121) ve önemli yabancı ot tohumlarına (Amaranthus caudatus L., Papaver rhoeas L., Sinapsis arvensis L.) uygulamalar yapılmıştır. Elde edilen sonuçlara göre, A. repens bitki ekstreleri Ege Pembesi domates çeşidinde ılık suda bekletme uygulamasında en düşük çimlenme yüzdesi (20,00) 15. günde elde edilmiş olup, H-2274 ve SC-2121 domates çeşitlerinde ise 15. gün ekstraktlarının çimlenmeyi tamamen engellediği ve bekleme süresi arttıkça çimlenmenin düştüğü tespit edilmiştir. Sıcakta bekletme uygulamasında ise 7. gün sonunda elde edilen ekstraktlar, domates tohumlarında çimlenmeyi tamamen engellemiş olup, her üç domates çeşitinde de çimlenme görülmemiştir. Bununla birlikte, A. repens bitki ekstrelerinin, domates kök-gövde uzunluğu ile yaş ağırlık-kuru ağırlığını da önemli oranda düşürdüğü belirlenmiştir. A. repens bitki ekstreleri, yabancı ot türlerinde hem ılık hem de sıcak suda bekletme uygulamalarında, 4. günden itibaren tohumların hiçbirisinde çimlenme görülmemiş olup (% 0,00), en toksik etki 4. gün ve sonrasında bekletilerek elde edilen ekstraktlarda görülmüştür. Bu uygulamalarda fide gelişimi olmadığı tespit edilmiş olup, uygulanan ekstraktların büyümeyi engelleyici etki gösterdiği belirlenmiştir. Abstract Our research examined the effects of extracts prepared from plant parts of Agropyron repens (L.) P. Beauv. on tomato and weed seed germination and seedling growth. Extracts are obtained from the A. repens plant kept at 25 ℃ (warm) and 80 ℃ (hot) on different days (1-4-7-15-30) and applied to tomato seeds (H-2274, Ege Pembesi, SC-2121) and important weed seeds (Amaranthus caudatus L., Papaver rhoeas L., Sinapsis arvensis L.). According to the results obtained, the lowest germination percentage (20.00) was obtained on the 15 th day of A. repens extracts in Ege Pembesi tomato variety in warm water soaking treatment, and it was determined that the extracts of the 15 th day were inhibited completely germination of H-2274 and SC-2121 tomato varieties and germination decreased as the waiting time of the extracts increased. In the hot soaking treatment, it was determined that the extracts obtained at the end of the 7 th day significantly inhibited germination in tomato seeds, and no germination was observed in any of the tomato varieties. However, it was revealed that A. repens plant extracts significantly decreased tomato root stem length, fresh weight, and dry weight. No germination was observed in any seeds after the 4 th day of treatments (0.00%), in weed species in 25 ℃ and 80 ℃ soaking treatments. In addition, the most toxic effect on weed species was observed in the extracts obtained by soaking in both warm and hot water treatments on the 4 th day and after, and it was determined that there was no seedling growth in these treatments, and it was determined that the applied extracts had a growth inhibitory effect.
Bu araştırmada Dünyada ve Türkiye’de artık önemi giderek
artan süs bitkilerinin üretiminde sorun olan yabancı ot problemi
araştırılmıştır. İnsanların süs bitkilerine yönelmesinde, çalışma
hayatlarındaki yorgunlukları atmak, evlerinde ve işyerlerinde
stresten uzak kalmak ve onların duygularına tercüman
olmak gibi sebepler başta gelmektedir. Süs bitkilerinin
önemini giderek anlayan insanoğlu, süs bitkileri ile gerek
bahçesinde gerek evinde duygusal bağlar kurduğu için onlara
daha özenli bakmak istemesi, bu konunun araştırılmasının
ana sebeplerinden biri olmuştur. Hayatımızın her alanında
karşımıza çıkacak olan yabancı ot problemi yine bu konuda
da karşımıza çıkmaktadır. Ülkemizde üretimi ve tüketimi artan
süs bitkileri ile ilgili yapılacak olan çalışmaların sayısının her
geçen gün artacağı aşikârdır.
The sustainable use of brackish water in agriculture demands the use of compatible cultivation systems. The objective of this study was measure differences in the water status of spinach plants (Spinacia oleracea L.), cv. Viroflay, cultivated in covered and uncovered soil and in a hydroponic floating system, using brackish water (EC = 0.8, 1.5, 3.0, 4.5, 6.0 and 7.5 dS m⁻¹) in the irrigation of plants in soil and replacement of nutrient solution in the floating system. At 38 days after transplanting, leaf water potential and osmotic potentials of the crop and of the systems were determined, as well as the osmotic adjustment, water consumption, leaf succulence, water use efficiency, leaf sodium content and yield. The hydroponic system showed a linear increase in the fresh weight of the leaves due to the salinity increase. The use of plastic cover attenuated the effects of salinity by 16 % in comparison to the uncovered soil, but the hydroponic system was the least affected by salinity, despite having the highest water consumption, which was 58 % higher than that of the uncovered soil. The main adaptive strategies observed in Spinacia oleracea L. cv. Viroflay in response to salinity were: increase in osmotic adjustment and leaf succulence and reduction in leaf water potential. The responses, positive in general, are corroborated by the values of sodium concentration in the leaves and fresh weight, which showed the highest results in the hydroponic cultivation for both variables. It is recommended to use the plastic cover or hydroponic methods during spinach cultivation, especially when using brackish water.
Novel superabsorbent membranes (SMs) consisting of polyvinyl alcohol (PVA), cellulose nanocrystals (CNCs) originated from rice husk (RH), nanosilica, glutaraldehyde and glycerine (G) were manufactured by a compression moulding process. RHs were used to isolate pure CNCs via mechanical and chemical treatments. RHs were used to improve water retention. These SMs were characterised by Fourier-transform infrared spectroscopy, scanning electron microscopy, mechanical testing and differential scanning calorimetry. SMs showed a greater equilibrium swelling capacity than neat cross-linked PVA. Moreover, the water transport mechanism of all SMs was found to follow Fickian diffusion. SMs exhibited good pH-dependent swelling reversibility and high-water retention capacity, making them more efficient water retention materials. The biodegradability of SMs was evaluated under environmental changes. The biodegradability of SMs was evaluated against environmental changes. The SM was also investigated for antimicrobial activity against pathogenic bacteria such as Candida albicans (fungus), Bacillus subtilis (Gram-positive), Staphylococcus aureus (Gram-positive), Proteus vulgaris (Gram-negative) and Erwinia carotovora (Gram-negative). SMs have been found to act as a useful water reservoir, which may make it useful in agricultural applications.
Abbreviation: Novel superabsorbent membranes (SMs) consisting of polyvinyl alcohol (PVA), cellulose nanocrystals (CNCs) originated from rice husk (RH), nanosilica (NS), glutaraldehyde (GLA) and glycerine (G) were manufactured by a compression moulding process. RHs were used to isolate pure CNCs via mechanical and chemical treatments. RHs were used to improve water retention. These SMs were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Mechanical Testing and Differential Scanning Calorimetry (DSC).
Background: Weed control represents a major issue in plant cultivation in containers. Manual weed control is very expensive and the use of chemical herbicide or plastic mulch films has a large environmental impact. The aim of this study was to test the efficacy of an experimental biodegradable chitosan-based mulching spray in controlling weed growth in containers. This research also studied the effect of this mulch on the growth of Viburnum lucidum Mill. plants to test for possible phytotoxic effects.
Results: The study compared a total of six treatments derived from three types of weed control (no weed control; herbicide, oxadiazon; mulching spray) applied in containers either filled only with the sterile substrate or filled with the sterile substrate and then artificially inoculated with seeds of the weed species [Sonchus asper (L.) Hill subsp. asper and Epilobium montanum L.]. The mulch controlled the weeds effectively for more than 2 months after its application even under severe weed infestation. The mulching spray controlled the emergence of S. asper more efficiently than E. montanum plants, probably because the latter has a stronger capacity to penetrate the mulch film during emergence.
Conclusions: Three months after its application, the mulch started to degrade and this allowed some weeds to emerge in the containers, but, in general, the mulch performed better than the herbicide. The chitosan-based mulch did not have any negative effect on the growth of V. lucidum plants.
Use of organic mulch materials such as pinebark, pinestraw, or various hardwood chips for weed control is a common practice in residential and commercial landscapes. Mulch can inhibit weed seed germination and growth through light exclusion, acting as physical barrier, reducing available moisture to weed seeds within the mulch layer, and through release of allelochemicals that may inhibit germination or growth of some weed species. Previous and current research on allelopathic chemicals present in mulch have focused on cover crops and their residues with an emphasis on agronomic crops. These materials would not be suitable in a landscape setting due to rapid decomposition, lack of commercial availability, and little aesthetic appeal. Research is needed concerning identification, quantification, extraction, mechanism of release, persistence, selectivity, genetic regulation, and mode of action of potential allelochemicals present in mulch materials used for landscape purposes. More knowledge of these natural chemicals could aid practitioners and homeowners in the selection of mulch and identify potential new mulch materials that could be utilized in these industries. The purpose of this review is to summarize previous research pertaining to allelopathic compounds present in commonly used mulch materials and identify new potential mulch materials that could be utilized in the landscape sector based upon allelopathic properties. Current areas where additional research is needed are also identified.
The objective of the research was to investigate the effects of pine bark, fresh grass and peat mulch on the ornamental value of Petunia × atkinsiana, Impatiens walleriana and Tagetes patula cultivars during the short growing period, and soil chemical properties (electrical conductivity, pH, organic matter, total N, P, K, Ca, Mg) and soil moisture in the second year in a temperate climate. Results show that fresh grass and peat mulch increased plant height of Petunia and Impatiens from 40 days after planting until the end of experiment. During the same period plant diameter of Impatiens and Tagetes was enhanced in all studied mulches, but plant diameter of Petunia was enlarged only with peat mulch. Impatiens number of flowers enhanced in all mulches, but in case of Tagetes the number was higher with pine bark. In comparison with unmulched treatment, soil moisture, electrical conductivity and pH increased in fresh grass and pine bark treatments. Soil Mg content was higher up to 15% in plots with fresh grass mulch. Plant diameter of all species was positively correlated with soil electrical conductivity.
Modern agriculture requires alternative practices that improve crop growth without negatively affecting the environment, as resources such as water and arable land grow scarcer while the human population continues to increase. Grafting is a cultivation technique that allows the plant to be more efficient in its utilization of water and nutrients, while nanoscale material engineering provides the opportunity to use much smaller quantities of consumables compared to conventional systems but with similar or superior effects. On those grounds, we evaluated the effects of chitosan-polyvinyl alcohol hydrogel with absorbed copper nanoparticles (Cs-PVA-nCu) on leaf morphology and plant growth when applied to grafted watermelon cultivar ‘Jubilee’ plants. Stomatal density (SD), stomatal index (SI), stoma length (SL), and width (SW) were evaluated. The primary stem and root length, the stem diameter, specific leaf area, and fresh and dry weights were also recorded. Our results demonstrate that grafting induces modifications to leaf micromorphology that favorably affect plant growth, with grafted plants showing better vegetative growth in spite of their lower SD and SI values. Application of Cs-PVA-nCu was found to increase stoma width, primary stem length, and root length by 7%, 8% and 14%, respectively. These techniques modestly improve plant development and growth.
In this article we report on the preparation of polymer composites from poly(vinyl alcohol), cattle horn meal and glycerol, which is the byproduct of biodiesel production. The effect of the amount of glycerol as well as of the particle size of horn meal on the mechanical, sorption properties, water vapour permeability, content of water soluble nitrogen and carbon in the films of the composites was studied. The composites were used for the preparation of coatings for the mulching of plants cultivated in pots. The liquid mulching composition was spread out on the surface of the growing substrate. After evaporation of water the polymer coatings, acting as a mulch films, were obtained. It was established that the proposed mulch films retain moisture in the pots and stimulate microbial activity of the soil. The rate of evaporation of water from the substrate coated with the mulch films was by 26–33 % lower than that from the unmulched substrate. The number of the fungal colony forming units in the substrates depended on the particle size of the horn meal in the mulch composite and was by 1.7 × 10⁴–4.1 × 10⁴ times higher compared with that found in the unmulched substrate. The composites were used for the mulching of the tomato sprouts cultivated in pots. It was established that the proposed mulch films stimulate growth of plants.
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Weeds are the major obstacles for enhancing wheat productivity. Rise in herbicide resistant weeds and shift in weed flora, warrants urgent attention on non-chemical approaches of weed management. Keeping these in view, a factorial experiment was conducted in randomized complete block design, during winter season of 2012-13. The treatments comprised of five wheat varieties [C-306, K-8027, K-0307, DBW-39 and HD-2888] and four mulching [No-mulch, rice straw (RS) 6 t/ha, maize straw (MS) 6 t/ha, and saw dust (SD) 6 t/ha] treatments. Among tested wheat varieties, DBW-39 and K-0307 smoother predominant weeds, reduced total weed density (20-40 per cent) and biomass (22-31 per cent); besides, they also showed higher plant height, population (especially during critical period of crop-weed competition) and test weight. DBW-39 produced higher yield to the tune of 2539 per cent over other varieties. Surface application of RS and MS mulches reduced the growth of predominant weeds, like Chenopodium album, Melilotus alba, and Phalaris minor; along with reduced density and biomass of total weed by nearly 50.0 per cent over no-mulch control. Furthermore, application of RS and MS produced 34.0 and 28.0 per cent higher yield over no-mulch. SD mulch was not effective in weed suppression and enhancing yield.
Greenhouse systems improve growing conditions of vegetable, fruit and ornamental crops. Greenhouse coverage protects plants from adverse atmospheric agents and, together with suitable equipment, influences and ultimately modifies the crop microclimate, thus lengthening the market availability of the products, improving their quality and allowing higher yields. Greenhouse production has a higher return per unit area than crops grown in the open field, but it requires the use of large amounts of energy to operate the equipment on one hand and generates huge quantities of wastes to be disposed of on the other hand. Protected cultivation can be environmentally unfriendly, especially in areas with a large concentration of greenhouses. Therefore, the steady worldwide increase in the area covered by greenhouses has generated the need for developing sustainable protected horticulture. Sustainable greenhouse horticulture can be achieved by means of different cultivation techniques, adequate equipment management and innovative materials aimed to reduce agro-chemicals and energy use, water consumption and waste generation. The achievement of optimal greenhouse microclimate conditions, the application of integrated pest management strategies and the use of innovative closed-loop fertigation systems with water recycling result in a significant reduction of plant diseases-and, consequently, of agro-chemicals use-and in a decrease in the consumption of both water and fertilisers as well as in the contamination of water bodies associated with nutrient leaching. Optimal climate control and reduction of energy consumption can be obtained by using suitable active and passive systems including proper control strategies for equipment and the use of innovative covering materials. Renewable energy sources and technologies, such as solar thermal and photovoltaic systems, can be used to reduce fossil fuel consumption for climate control. Waste generation mainly concerns the use of materials such as covering and mulching plastic films that must be disposed of at the end of their life; the introduction of innovative biodegradable materials can reduce this kind of waste, improving crop sustainability. The chapter presents the design concepts of greenhouse sustainable systems based on the application of innovative covering materials, microclimate control strategies, renewable energy sources and the use of leading technologies. In addition, it considers fertigation and integrated pest management strategies that may contribute to sustainable operations.
Mulches provide aesthetic, economic and environmental benefits to urban landscapes. Mulching is especially useful in the establishment of trees in landscapes that receive minimal care, such as restoration sites. In general, mulches improve soil health, creating healthy populations of plants and associated animals. These biodiverse, stable landscapes are more resistant to stress, are more aesthetically pleasing, require fewer applications of pesticides and fertilizers, and are ultimately more sustainable than those without mulch cover. All mulches are not created equally, however, and this review compares the costs and benefits of landscape mulches as reported in the scientific literature. It also presents real and perceived problems associated with various landscape mulches.
Natural fibers are fine examples of renewable resources that play an important role in the composites industry, which produces superior strength comparable to synthetic fibers. Poly(vinyl alcohol) (PVA) composites in particular have attracted enormous interest in view of their satisfactory performance, properties and biodegradability. Their performance in many applications such as consumer, biomedical, and agriculture is well defined and promising. This paper reviews the utilization of natural fibers from macro to nanoscale as reinforcement in PVA composites. An overview on the properties, processing methods, biodegradability, and applications of these composites is presented. The advantages arising from chemical and physical modifications of fibers or composites are discussed in terms of improved properties and performance. In addition, proper arrangement of nanocellulose in composites helps to prevent agglomeration and results in a better dispersion. The limitations and challenges of the composites and future works of these bio-composites are also discussed. This review concludes that PVA composites have potential for use in numerous applications. However, issues on technological feasibility, environmental effectiveness, and economic affordability should be considered.
Container production has increased rapidly in many parts of the U.S. over the past 15 years. Container production has been the fastest growing sector in the nursery industry and the growth is expected to continue. Weed growth in container-grown nursery stock is a particularly serious problem, because the nutrients, air, and water available are limited to the volume of the container. The extent of damage caused by weeds is often underestimated and effective control is essential. Various researchers have found that as little as one weed in a small (1 gal) pot affects the growth of a crop. However, even if weeds did not reduce growth, a container plant with weeds is a less marketable product than a weed-free product. Managing weeds in a container nursery involves eliminating weeds and preventing their spread in the nursery, and this usually requires chemical controls. However, chemical controls should never be the only management tools implemented. Maximizing cultural and mechanical controls through proper sanitation and hand weeding are two important means to prevent the spread and regeneration of troublesome weeds. Cultural controls include mulching, irrigation methods (subirrigation), and mix type. Nursery growers estimate that they spend 4000/acre of containers for manual removal of weeds, depending on weed species being removed. Economic losses due to weed infestations have been estimated at approximately $7000/acre. Reduction of this expense with improved weed control methodologies and understanding weed control would have a significant impact on the industry. Problems associated with herbicide use in container production include proper calibration, herbicide runoff concerns from plastic or gravel (especially when chemicals fall between containers) and the need for multiple applications. As with other crops, off-site movement of pesticides through herbicide leaching, runoff, spray drift, and non-uniformity of application are concerns facing nursery growers. This article reviews some current weed control methods, problems associated with these methods, and possible strategies that could be useful for container nursery growers.
The objective of this study was to characterize the tensile strength (TS), tensile modulus of elasticity (TM) and shore hardness (HA) of biodegradable pinewood sawdust (PWS)/polyvinyl alcohol (PVA) composites as affected by press temperature, starch/PVA ratio and press time. PWS/PVA composites were prepared by hot press molding under different conditions. The results showed that the TS and TM values of the composite particleboard with press temperature of 140°C were greater than those of the composite particleboard with press temperature of 120, 160 and 180°C. HA decreased with the increase of press temperature. Effect of press time shows the similar trend as the press temperature. The composite particleboard pressed with 10 and 12 min possess the highest TS and TM respectively. when starch/PVA ratio increased from 0 to 17%, 33% and 50%, the TS and HA decreased, however, the tensile modulus increased because elongation at break of composite particleboard significantly decreased when starch/PVA ratio increased. Composites with PVA as matrix material was not reported before.
An investigation was done on the effect of different types of organic mulches that were applied in form of straw to the soil mulching process, on the weed infestation, number, and fresh mass of weeds in broccoli cv. Milady F1 (Brassica oleracea L. var. italica Plenck) and tomato cv. Polfast F1 (Lycopersicon esculentum Mill.) grown under polypropylene fibre as a covering, or grown without a covering. The different types of organic straw mulches were: rye (Secale cereale L.), corn (Zea mays L.), rape (Brassica napus L. subsp. napus), and buckwheat (Fagopyrum esculentum Moench.). All the organic mulches were applied at a dose of 10 t/ha. The effect of the mulches was compared to a control plot which had no mulch. The type of organic mulch applied to the soil mulching process influenced species composition, number, and fresh mass of weeds. This effect could be the result of the properties of the mulch (colour, structure, etc.) or the allelopathic effect on the germination and growth of individual weeds species. Irrespective of the investigated factors, 24 and 25 weeds species, respectively, were observed immediately after cover removal and before broccoli and tomato harvest. In the first date of estimation Chenopodium album L., Echinochloa crus-galli (L.) P. Beauv., Fallopia convolvulus (L.) Á. Löve, Stellaria media (L.) Vill., and Viola tricolor L. dominated, however, before the vegetables were harvested Ch. album, V. tricolor, Veronica arvensis L., and E. crus-galli dominated. An application of polypropylene fibre contributed to an increase in the number and fresh mass of weeds in both vegetables in the first date of estimation (after cover removal). During this period, vegetables cannot compete with weeds. It is important to note, though, that before the vegetables were harvested, a decrease was found in the number and fresh mass of weeds in the covered plots. The most efficient weed limiter, both after cover removal and also before the broccoli and tomatoes were harvested, was buckwheat and rye straw, respectively.
Nursery growers estimate that they spend 4000/acre (9880/ha) of containers for manual removal of weeds, depending upon weed species being removed. Economic losses due to weed infestations have been estimated at about 17,290/ha). Herbicide treated bark nuggets were found extremely effective for weed control in studies during 1998, regardless of whether oxyfluorfen, oryzalin, or isoxaben were applied to the bark. A study conducted in 2000 compared 24 treatments of novel nonchemical alternatives, conventional chemical practices and herbicide treated barks. Four of the best treatments were herbicide treated douglas fir bark, specifically, small [<1 inch (2.5 cm) length] douglas fir nuggets treated with oryzalin at the 1× rate, large (>1 inch length) douglas fir nuggets treated with oryzalin at the 0.5× rate, small douglas fir nuggets treated with oryzalin at the 0.5× rate and large douglas fir nuggets treated with flumioxazin at the 1× rate. The four bark treatments indicated above provided equivalent efficacy and phytotoxicity to Geodiscs. Penn Mulch and Wulpack provided poor weed control. Mori Weed Bag, a black polyethylene sleeve, and Enviro LIDs, a plastic lid provided less control than herbicide treated bark. Compared to the bark alone, herbicide treated bark provides a 1.8-fold increase in efficacy and a 2.8-fold extension in duration of efficacy. Compared to the herbicide alone, herbicide treated bark provides a 1.5-fold increase in efficacy and a 2.2-fold reduction in phytotoxicity. Of the innovative weed control products tested herbicide treated bark provided the most promising results. The data support that the bark nuggets are possibly acting as slow release carriers for the herbicides or reducing the leaching potential of the herbicides. Recent studies have indicated that the controlled release of herbicides using lignin as the matrix offers a promising alternative technology for weed control.
Organic agriculture is growing in importance worldwide. In the United States, the rate of increase of organic growers was estimated at 12% in 2000. However, many producers are reluctant to undertake the organic transition because of uncertainty of how organic production will affect weed population dynamics and management. The organic transition has a profound impact on the agroecosystem. Changes in soil physical and chemical properties during the transition often impact indirectly insect, disease, and weed dynamics. Greater weed species richness is usually found in organic farms but total weed density and biomass are often smaller under the organic system compared with the conventional system. The improved weed suppression of organic agriculture is probably the result of combined effects of several factors including weed seed predation by soil microorganisms, seedling predation by phytophagus insects, and the physical and allelopathic effects of cover crops.
The use of plastic mulch in agriculture has increased dramatically in the last 10 years throughout the world. This increase is due to benefits such as increase in soil temperature, reduced weed pressure, moisture conservation, reduction of certain insect pests, higher crop yields, and more efficient use of soil nutrients. However, disposing of used plastic films, which cause pollution, has led to development of photodegradable and biodegradable mulches. Here we review the use of plastic mulches in agriculture, with special reference to biodegradable mulches. Major topics discussed are (1) history of plastic mulch and impact on crop yield and pest management, (2) limitations of polyethylene mulches and potential alternatives, (3) biodegradable and photodegradable plastic mulches, (4) field performance of biodegradable mulches, and (5) use of biodegradable plastic mulches in organic production. We found that (1) despite multiple benefits, removal and disposal of conventional polyethylene mulches remains a major agronomic, economic, and environmental constraint; (2) early use of photodegradable plastic mulch during the 1970s and 1980s, wrongly named biodegradable mulch films, discouraged adoption of new biodegradable mulch films because they were too expensive and their breakdown was unpredictable; (3) biodegradable plastic films are converted through microbial activity in the soil to carbon dioxide, water, and natural substances; (4) polymers such as poly(lactic acid), poly(butylene adipate-coterephthalate), poly(ε-caprolactone), and starch-based polymer blends or copolymers can degrade when exposed to bioactive environments such as soil and compost; (5) with truly biodegradable materials obtained from petroleum and natural resources, opportunity for using biodegradable polymers as agricultural mulch films has become more viable; and (6) the source of polymer and additives may limit use of some biodegradable mulches in organic production. More knowledge is needed on the effect of biodegradable mulches on crop growth, microclimate modifications, soil biota, soil fertility, and yields.
Laboratory trials were performed to test germination and emergence characteristics of jimsonweed (Datura stramonium L.) seeds buried in 10 different soil types (with or without the control of soil external gas environment) with pronounced sandy or clay texture. The aim of the experiments was to investigate if the physical characteristics of the soils were involved in both buried-seed ecology and emergence dynamics. Germination inhibition due to burial depth was found to be directly proportional to clay content and inversely proportional to sand content. Measurement of soil air permeability showed a close relation between gas exchange potential and depth-mediated germination inhibition. Comparative analysis of the germination response in nonsoil and soil hypoxia suggested that inhibition is caused not so much by hypoxia per se as by the presence of fermenting metabolites that could not easily be eliminated due to decreased respiratory activity. In situ inspection of buried seeds also revealed that the increased time required for emergence in clay soils is primarily due to increased mean germination time rather than greater difficulty in seedling penetration upwards through the soil before emergence. Partial removal of germination inhibition of buried seeds was facilitated by elevated air oxygen availability but only with sandy soils, showing that inhibition is closely linked to soil ability to induce gas exchange with external air. At excessive burial depth (12 cm), seeds exhibited induction of secondary dormancy independent of soil texture. In conclusion, these experiments demonstrated that soil physical properties have a strong effect on buried-seed ecology and consequently on seedbank dynamics in the agroecosystem.
This research evaluated the effectiveness of biodegradable mulches for weed control in container-grown 'Martin' giant arborvitae (Thuja plicata) and measured the effects of these mulches on evaporation and substrate temperature. The experiment was carried out in the 2008 and 2009 growing seasons. Four biodegradable mulching materials were tested and compared with a chemical control (oxadiazon) and a non-mulched/non-treated control. Two levels of overhead irrigation were evaluated: 1) daily irrigation to container capacity (well watered) and 2) daily irrigation to 30% of container capacity (water stressed). Two weed management regimes were used: 1) hand weeding three times during the growing season and 2) no weeding until the end of the growing season. Plants were potted in 3-L containers and arranged in a split-split plot design in an experimental nursery. Ornamental shoot dry weight was measured at the end of the growing season. Weed shoot dry weight per container was recorded after each hand weeding. Water content per pot (as a percentage of water-holding capacity) was measured by weighing containers every 2 hours during the day. Substrate temperature was measured in the warmest period of the day. Mulches limited weed growth to the same extent as the chemical control. In 2008, mulched plants resulted in a higher shoot dry weight than non-treated and non-mulched plants, while in the second year, no differences were observed. The black color of the 3-L containers was probably the main factor driving substrate temperature increase, indicating mulching materials did not affect substrate temperatures. In both experiments, container water content was unaffected by mulching materials. Results seem to demonstrate that transpiration is the main component of water loss from container-grown giant arborvitae plants.
Trials were carried out to investigate the effects of seed burial depth on seedling emergence rate of 20 weed species. Marked depth-mediated variation in emergence ability of the different species was observed, together with a general pattern of decreasing emergence with increasing soil depth. At 10 cm, only johnsongrass, velvet-leaf, catchweed bedstraw, and cutleaf geranium emerged, albeit only in limited numbers. Species most severely inhibited by burial depth were buckhorn plantain, large crabgrass, common purslane, chickweed, and corn spurry, none of which emerged from beyond 6 cm. In all species, depth-mediated inhibition was found to be sigmoidal (polynomial regression). In addition, the number of seedlings and rate of seedling emergence decreased when depth of burial increased. The depth at which the number of emerged seedlings was halved varied by species and ranged from 3.6 cm for common purslane and chickweed to 7 cm for velvetleaf and catchweed bedstraw. Excessive burial depth generally induced dormancy (in roughly 85% of cases) rather than suicide germination. A close inverse relation (second-degree equation) between seed unit weight and depth-mediated inhibition was observed. The physiological involvement of depth inhibition in seed bank ecology is discussed.
With empty containers, nontarget herbicide loss was 23 percent when the containers were spaced container to container. Spacing the containers on 20 (8 in) and 30 cm (12 in) centers resulted in nontarget losses of 51 and 80 percent loss respectively. Nontarget losses were similar when a dense canopy plant (Rhododendron × ‘Trouper’) and an open canopy plant (Berberis thunbergii ‘Crimson Pygmy’) were spaced container to container or on 20 (8 in) or 30 cm (12 in) spacings.
Thirty-two container nurseries were surveyed concerning weed management strategies. Handweeding costs ranged from 608–1401/ha (246–567/acre), with hourly wages paid for handweeding ranging from 3.97/hour. Nurseries averaged 3 applications of preemergence applied herbicides annually. Primary herbicides applied were OH-2 (oxytluorfen + pendimethalin), Rout (oxytluorfen + oryzalin) and Ronstar (oxadiazon). Problem weeds identified by the participants were prostrate spurge (Euphorbia supina Raf.), oxalis (Oxalis sp.), eclipta (Eclipta alba (L.) Hasskarl) and nutsedge [Cyperus esculentus L. (yellow) and C. rotundus L. (purple)]. Weed control material used under containers varied with the nursery size.
Leaf deposition of PM10–100, PM2.5–10, PM0.2–2.5 and of 21 elements was investigated in a roadside vegetation barrier formed by i) two evergreen shrub species (Photinia × fraseri, Viburnum lucidum), with ii) two planting densities (0.5, 1.0 plant m−2), at iii) three distances from the road (2.0, 5.5, 9.0 m), at iv) two heights from the ground (1.5, 3.0 m), and on v) three dates (Aug, Sep, Oct).
The presence of black and brown on-leaf PM10–100 and their element composition were detected by microscopy and image analysis. Pollutant deposition was also measured using passive samplers at five distances from the road (2.0, 5.5, 9.0, 12.5, 19.5 m) in the area of the barrier and in an adjacent lawn area.
V. lucidum had more PM2.5–10 and PM0.2–2.5 on leaves than P. × fraseri, while most elements were higher in P. × fraseri. Most pollutants decreased at increasing distances from the road and were higher at 1.5 m from the ground compared to 3.0 m.
Higher planting density in P. × fraseri enhanced the deposition of PM10–100 and PM2.5–10, while in V. lucidum, the planting density did not affect the depositions.
Black PM10–100 decreased a long distance from the road and was entirely composed of carbon and oxygen, which was thus identified as black carbon from fuel combustion.
The vegetation barrier had a higher deposition of most PM fractions at 5.5–12.5 m, while in the lawn area, depositions did not change. At 19.5 m, the PM10–100 was 32% lower behind the barrier than in the lawn area. In conclusion, the vegetation barrier changed the deposition dynamics of pollutants compared to the lawn area. These results strengthen the role of vegetation barriers and shrub species against air pollution and may offer interesting insights for the use of new road green infrastructures to improve air quality.
Bentgrass was used to bioassay oxyfluorfen in leaching experiments done in columns of soilless potting media and soils, with herbicide incorporated into the upper 2 to 4 cm. Depth of herbicide leaching increased in order in the following soils: peat and sand (1:1) mix, Stockton clay soil, Yolo fine sandy loam soil, and redwood bark and sand (3:1) mix. Depth of leaching was not related to soil organic matter content. Equilibration experiments showed that peat adsorbed 4 to 5 times more oxyfluorfen than redwood bark. Less leaching was observed in potting mixtures containing peat than bark. Raising the oxyfluorfen dose from 20 to 200 ppmw increased the depth of leaching and concentration of herbicide in the leachate, while a 10-fold increase in water volume had only a limited effect. Twenty ppmw of oxyfluorfen incorporated in the top of a peat-containing potting medium has a low risk of leaching out of the container.
Managing weeds in organic cropping systems is notoriously difficult. We analyzed the seed bank dynamics in vegetable crop rotations carried out in both the typical Mediterranean scenarios of the open field and greenhouse. The lower seed bank detected in the greenhouse (about 53,000 seeds m⁻²) showed a higher emergence rate than the seed bank found in the open field, which was almost twice the size. This higher emergence rate was due both to: i) the more favorable temperature in the greenhouse, and ii) the less depth-mediated soil-imposed dormancy, due to the seed bank being at a lower depth as a result of minimum tillage. A strong infestation of Cyperus rotundus was found in the greenhouse again, due to the tuber arrangement in the shallowest soil layer (0–10 cm). The ubiquitous and abundant Amaranthus retroflexus, taken as a model to investigate the dormancy-status of exhumed seeds showed that the lower emergence rate in the open field, was not due to dormancy but exclusively to depth-mediated soil inhibition. In addition, the calculation of various indexes of the weed seed bank botanical composition highlighted that the more quantitatively abundant greenhouse weed community was formed by more graminoid species (poaceae and cyperaceae), perennial species, C4 photosynthetic pathway species and by lower biodiversity. Lastly agronomic strategies are proposed which could improve the weed control sustainability in organic cropping systems.
Four organic mulches, screened pinebark, hardwood (primarily oak), cypress and decorative pinebark nuggets, applied at depths of 0, 5, 10, and 15 cm (0, 2, 4, 6 in) with or without an inorganic weed barrier fabric, were tested in field and container studies to determine their effect on weed suppression, soil pH, soil nitrogen content, and growth of Ligustrum japonicum. Results indicated that mulch applied at shallower depths, in combination with a weed barrier, provided optimal weed control without tying up soil nitrogen or reducing plant growth. Coarser mulches out-performed finer-textured materials. Most effective weed control was obtained with decorative pinebark nuggets with weed barrier fabric at a 15 cm (6 in) depth of application when compared to unmulched controls. As the depth of mulch was increased, soil pH, soil nitrogen content, and visual rating of plant growth decreased. Mulches over 10 cm (4 in) deep tended to inhibit plant growth, although optimum depth was dependent on the mulch material used.
Weed management is key component of establishing and sustaining a profitable organic orchard. Good site preparation is a critical part of an orchard establishment plan. Pre-plant weed control coupled with addressing soil fertility issues before planting can dramatically increase the options available to producer for weed management, while reducing the time to commercially viable levels of fruiting and harvest. Tillage may be the best option on sites with perennial rhizomatous weeds and low soil fertility, or where there is high risk of rodent damage to the crop. Dead organic mulches are best suited to sites with low presence of perennial rhizomatous weeds and sites where at least moderate levels of soil fertility are present. While living mulches tend to provide a desirable habitat in the orchard understory, they are competitive with the crop for water and nutrients, regardless of whether they are mowed or not. They should only be used on sites with good background soil fertility, with frequent mowing, and where climate or irrigation minimize risk of moisture stress. Most manufactured mulches can provide effective weed control for a longer period of time but reduce soil fertility management options. The use of biodegradable mulches under dead organic mulches poses interesting possibilities and should be studied further. Organic herbicides are presently not effective enough or too costly to be used as the primary means of weed control but would be a useful tool for spot and edge control of weeds in mulches.
Five organic mulches (pine bark, hardwood bark, cedar chips, longleaf pine needles, shortleaf pine needles), used alone or in combination with two inorganic mulches (black polyethylene, woven polypropylene), were evaluated over two years for weed control, durability, aesthetic value, and influence upon soil temperature. Organic mulches reduced total weed counts by 50% compared to control plots. and underlaying organic mulches with polyethylene resulted in complete control. Polypropylene, used in combination with organic mulch, was ineffective in controlling perennial weed species. Pine bark was the most durable organic mulch, requiring the least replenishment (70% initial volume) after 630 days. Durability of organic mulches increased when underlaid with polyethylene. Longleaf pine needles were rated most attractive, and underlying organic materials with either polyethylene or polypropylene enhanced appearance. Organic mulches reduced maximum daily temperatures at the soil surface by 2.2–3.3°C (4–6°F) and increased minimum daily temperatures by 1.1–2.2°C (2–4°F). However, the type of organic mulch did not affect temperatures at the soil surface.
A two - factor experiment was carried out in the Experiment Station of Lithuanian University of Agriculture in 2004 - 2005. Different organic mulches, chopped wheat straw, peat, wood chips, grass and wood chips, and wood chips which had been stored for 8 years (only in 2005) were overspead by a layer of 5 cm and 10 cm thickness. The influence of different organic mulches on weed emergence was evaluated. All organic mulches reduced weed germination. The positive effect of mulches was particularly obvious in the period of intensive germination of weeds. Straw, peat and wood chips had the strongest influence on the decrease of weed germination, however, it is important to make sure that mulches are not infected with weed seeds. Mulch of chopped grass is quick to decompose, therefore, repeated mulching is required to protect the crop from weeds. Key wods: organic mulches, weed emergence, annual weeds, perennial weeds
Herbicide use in containerized plant production nurseries is a vital tool for weed management and the production of plants desired by the consumer. Clemson University researchers have conducted studies aimed at determining the amount of herbicide runoff during normal nursery operation, if herbicides accumulate in containment ponds at nurseries, and how herbicide runoff could be reduced. A 2-year study at commercial nurseries found that herbicide concentrations were higher in containment ponds soon after herbicide application, when compared with months with less herbicide application; and herbicides did not accumulate over the 2-year period. Herbicide runoff was greatest immediately after application and up to 15% of the herbicide applied was lost in the first irrigation event after application when using more water soluble herbicides. Bed material and herbicide formulation were also important in determining the amount of herbicide lost. Total losses were highest from plastic- and fabric-covered beds when using granular formulations and highest from gravel beds when spray formulations were used. The combination of using cyclic irrigation and grass waterways resulted in a reduction of about 25% of isoxaben loss when compared with clay and gravel waterways with continuous irrigation. The effects of reduced herbicide treatments compared to standard spray schedules were evaluated on herbicide transport, weed development, and plant growth and health. Results indicated that plant marketability was not affected, and total herbicide runoff was significantly reduced. Based on these studies, several recommendations can be made to commercial container plant production nurseries, which should reduce herbicide runoff and thereby reduce the environmental concerns associated with nurseries.
Use of preemergence and postemergence herbicides is the most effective and economical method of weed control in landscape planting beds. When used correctly, herbicides can provide satisfactory weed control, reduce labor costs, and cause little or no negative environmental impacts. Major factors in herbicide efficacy include choosing the correct herbicide for the weed species present, following proper calibration procedures, and applying herbicides at the correct timing. The objective of this review is to provide a comprehensive analysis of the research pertaining to herbicide use in landscape planting beds and present 1) the advantages and disadvantages of common chemical weed control strategies, 2) the most effective preemergence and postemergence herbicides in various landscape scenarios, 3) potential environmental concerns pertaining to improper application of herbicides, and 4) highlight knowledge gaps where additional research is needed or improvements could be made.
. Herbicide use in containerized plant production nurseries is a vital tool for weed management and the production of plants desired by the consumer. Clemson University researchers have conducted studies aimed at determining the amount of herbicide runoff during normal nursery operation, if herbicides accumulate in containment ponds at nurseries, and how herbicide runoff could be reduced. A 2-year study at commercial nurseries found that herbicide concentrations were higher in containment ponds soon after herbicide applica-tion, when compared with months with less herbicide application; and herbicides did not accumulate over the 2-year period. Herbicide runoff was greatest immediately after applica-tion and up to 15% of the herbicide applied was lost in the first irrigation event after applica-tion when using more water soluble herbicides. Bed material and herbicide formulation were also important in determining the amount of herbicide lost. Total losses were highest from plastic-and fabric-covered beds when using granular formulations and highest from gravel beds when spray formulations were used. The combination of using cyclic irrigation and grass waterways resulted in a reduction of about 25% of isoxaben loss when compared with clay and gravel waterways with continuous irrigation. The effects of reduced herbicide treatments compared to standard spray schedules were evaluated on herbicide transport, weed development, and plant growth and health. Results indicated that plant marketability was not affected, and total herbicide runoff was significantly reduced. Based on these studies, several recommendations can be made to commercial container plant production nurseries, which should reduce herbicide runoff and thereby reduce the environmental concerns associated with nurseries.
The first weed disc (Weed Guard) was introduced to Ontario in the early 1980s. They were made of semirigid plastic similar to 45-rpm records. Small holes allow water to penetrate but weeds germinating on the substrate often grow through them. In the 1990s, we obtained 85% reduction of container weeds using discs made from geotextile fabric (Mori Guard) or foam (similar to polyfoam used for container winter protection). The foam disc tended to curl upward at the edges, become easily windblown, and tended to partially expose the surface of the container mix. During the past 15 years, we have annually reused the same fabric discs (now unavailable due to high unit cost), and have tested various other weed discs, including several new-generation types and also the Mori Weed Bag. The new-generation discs are fabricated from materials such as fabric (Tex-R Geodisc), pressed peat moss (Biodisc), corrugated cardboard (Corrudisc), and plastic (Enviro LID). Both Tex-R Geodisc and Enviro LID were as effective or better in controlling weeds than weekly hand-weeding, herbicides, or the Mori Guard fabric disc. The Mori Weed Bag, a patented black polyethylene sleeve with prepunched holes fitted around the container like a florist's plant prepared for market, is used effectively and almost exclusively by one Ontario nursery. We also tested two types of insulated blanket covers, which when placed around the ball of above-ground container-grown trees, prevented weed growth during the summer and also protected the root ball against cold during the winter. We introduced the garbage bag sleeve, the ultimate no-weed method for pot-in-pot tree culture, which also reduces water use and frequency of irrigation. Due to factors such as under-performance, insufficient demand, and/or high costs, only certain discs are currently manufactured: Weed Guard, Tex-R Geodisc, Biodisc, and Enviro LID. The Mori Weed Bag is available but not the insulated blankets.
Weeding has traditionally been a labour intensive operation in crop production. The use of herbicides was rapidly accepted by many farmers and became an accepted part of crop husbandry, although a few farmers always questioned the widespread use of chemicals in farming, and the concept of organic farming necessitated a non-chemical approach to weed control.The recent upsurge in environmental awareness of the public, interest in organic food production and some problems with herbicide use, has led to a range of techniques and machines being developed for non-chemical weed control. Thermal and mechanical techniques are reviewed for cereal and row crop production.
This study is meant to provide a contribution in recent developments of biodegradable polymeric materials applied in agricultural practices with particular reference to the mulching segment. Special attention has been devoted to material based on renewable resources or utilization of waste products from agro-industrial activities, thus suggesting cost-effective and environmentally sound solutions to specific social needs. In the present contribution PVA solubility at room temperature has been improved by premixing with chemical additives and proteic materials. Waste materials from ethanol production by corn fermentation and from wood industries have been used as, respectively starch-based and lignocellulosic additives. The prepared formulations were applied on the soil by conventional spraying agricultural equipment. Time of permanence of the film formed on the soil was monitored as well as the effect on corn growth and yield production. Finally, in order to investigate the final fate of the PVA applied on the soil, a test was performed in lysimeters, with half of the lysimeters cropped with maize plants. PVA amount applied for the mulching test was in order of 5-10 g PVA/1 m2; under those conditions it resulted completely absorbed and no presence of PVA was recorded in the leached solutions.
Concern about potential increases in weed populations without the use of herbicides has limited the uptake of organic farming. However, as both public demands for organic produce and the profile of organic farming have increased in recent years, so too has the range of weed control options. Progress in cultural methods of weed control has included the use of novel weed-suppressing cover crops, and the identification of specific crop traits for weed suppression. Direct weed control has also seen developments, with new implements appearing on the market that could benefit in the future from sophisticated machine guidance and weed detection technology. Advances in novel techniques such as steaming have also been made. Many weed control operations in organic systems present the grower with conflicts, and both these and many of the most recent developments in organic weed control are reviewed. An increase in our understanding of weed biology and population dynamics underpins long-term improvements in sustainable weed control. The outcome of these studies will benefit conventional and organic growers alike. Emphasis is given to the need for flexibility and a combination of weed biology knowledge, cultural methods and direct weed control to maintain weed populations at manageable levels.
Poly(vinyl alcohol) (PVA) is recognized as one of the very few vinyl polymers soluble in water also susceptible of ultimate biodegradation in the presence of suitably acclimated microorganisms. Accordingly, increasing attention is devoted to the preparation of environmentally compatible PVA-based materials for a wide range of applications. The present article is aimed at providing a survey of the available information on the environmental fate of PVA and PVA-based materials. Literature data and recent advances on the biochemistry and microbial physiology of PVA biodegradation and on the influence of environmental conditions are discussed along with the biodegradation processes of other water-soluble materials. The biodegradation behaviors of several PVA-based materials including blends, composites and copolymers are also reviewed and discussed.
A research cooperation between USDA and the University of Pisa led to the development of several composite blends of poly(vinyl alcohol) (PVA) and lignocellulosic fibers. The cast films were prepared by blending orange fibers (OR-fibers) and PVA with and without cornstarch to yield flexible and cohesive films. To improve properties, films were also prepared by crosslinking PVA, starch and OR-fibers with hexamethoxymethylmelamine (HMMM). Films were evaluated for their thermal stability, water permeability and biodegradation. Thermal gravimetric analyses indicated the potential usefulness of such blends in several thermoplastic applications. Films were permeable to water, and retained the moisture content in the soil while retaining their integrity. Films generally biodegraded within 30 days in compost, achieving between 50-80% mineralization. Both neat PVA and blends that had been crosslinked showed comparatively slow degradation. A possible stimulating effect of lingocellulosic fillers on the biodegradation of PVA in blends has been observed.
Blends and composites based on environmentally degradable-ecocompatible synthetic and natural polymeric materials and fillers of natural origin have been prepared and processed under different conditions. Poly(vinyl alcohol) (PVA) was used as the synthetic polymer of choice by virtue of its capability to be processed from water solution or suspension as well as from the melt by blow extrusion and injection molding. Starch and gelatin were taken as the polymeric materials from renewable resources. The fillers were all of natural origin, as waste from food and agro-industry consisted of sugar cane bagasse (SCB), wheat flour (WF), orange peels (OR), apple peels (AP), corn fibres (CF), saw dust (SD) and wheat straw (WS). All the natural or hybrid formulations were intended to be utilized for the production of:
Some typical prototype items have been prepared and characterized in relation to their morphological and mechanical properties and tested with different methodology for their propensity to environmental degradation and biodegradation as ultimate stage of their service life. A relationship between chemical composition and mechanical properties and propensity to biodegradation has been discussed in a few representative cases.
* Here we investigated photosynthetic traits of evergreen species under a deciduous canopy in a temperate forest and revealed the importance of CO2 assimilation during winter for annual CO2 assimilation. * Saplings were shaded by the canopy trees from spring through to autumn, but were less shaded during the winter months. Photosynthetic rates at light saturation (Aarea) were lower during winter than during the growing season. Aarea was higher in Camellia, Ilex and Photinia than in Castanopsis, Cleyera and Quercus during the winter, but differed little during summer and autumn. * Estimated daily CO2 assimilation (Aday) was higher during the winter than during the growing season in Camellia, Ilex and Photinia but was higher than that during the growing season only at the beginning and end of winter in Castanopsis, Cleyera and Quercus. Aday was higher in Camellia, Ilex and Photinia than in Castanopsis, Cleyera and Quercus but differed little among them during the growing season. * These results reveal the importance of winter CO2 assimilation for the growth of Camellia, Ilex and Photinia. Furthermore, differences in annual CO2 assimilation among species are strongly modified by species-specific photosynthetic traits during the winter under deciduous canopy trees.
Published studies focused on characterizing the allelopathy-based weed suppression by rye cover crop mulch have provided varying and inconsistent estimates of weed suppression. Studies were initiated to examine several factors that could influence the weed suppressiveness of rye: kill date, cultivar, and soil fertility. Ten cultivars of rye were planted with four rates of nitrogen fertilization, and tissue from each of these treatment combinations was harvested three times during the growing season. Concentrations of a known rye allelochemical DIBOA (2,4-dihydroxy-1,4-(2H)benzoxazine-3-one) were quantified from the harvested rye tissue using high performance liquid chromatography (HPLC). Phytotoxicity observed from aqueous extracts of the harvested rye tissue correlated with the levels of DIBOA recovered in harvested tissue. The amount of DIBOA in rye tissue varied depending on harvest date and rye cultivar, but was generally lower with all cultivars when rye was harvested later in the season. However, the late maturing variety 'Wheeler' retained greater concentrations of DIBOA in comparison to other rye cultivars when harvested later in the season. The decline in DIBOA concentrations as rye matures, and the fact that many rye cultivars mature at different rates may help explain why estimates of weed suppression from allelopathic agents in rye have varied so widely in the literature.
Mulching pot plants to combat weeds
- S Benvenuti
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- A Pardossi
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PistoiaIl vivaismo ornamentale tra competitività e sostenibilità ambientale
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Study on environmental risk assessment of glyphosate leakage
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International Statistics Flowers and Plants
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Mulching pot plants to combat weeds
- Benvenuti