Article

Evaluation of exclusion netting for insect pest control and fruit quality enhancement in tree crops

Authors:
  • Griffith University, Nathan, Queensland, Australia
To read the full-text of this research, you can request a copy directly from the authors.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Future studies should directly compare infestations of A. fraterculus in areas with and without anti-hail netting, with the possibility of including one area as a true control, because previous studies have indicated that the nets can act as a physical barrier to pests, reducing the levels of infestation and damaged fruits (Lloyd et al., 2005;Tasin et al., 2008;Chouinard et al., 2017). This behavioral response was observed for Cydia pomonella Linnaeus (Lepidoptera: Tortricidae) in apple orchards in Italy, France and Canada. ...
... In these studies, in addition to functioning as a physical barrier, the net impaired the reproduction of the moths (Tasin et al., 2008;Sauphanor et al., 2012;Baiamonte et al., 2016;Chouinard et al., 2016). Lloyd et al. (2005) reported that the use of exclusion netting (2 × 2 mm mesh) in a totally closed system prevented the entry of Bactrocera tryoni Froggatt (Diptera: Tephritidae) into peach (Prunus persica) and nectarine (Prunus persica var. nucipersica) orchards in Australia. ...
... nucipersica) orchards in Australia. In that study, although seasonal peaks of the species were recorded in the adjacent plots, which had no netting, no damaged fruit were found in the orchards protected by netting (Lloyd et al., 2005). In Canada, the use of exclusion nets installed over each planting row down to ground level also significantly reduced the percentage of apple fruits damaged by Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) (Chouinard et al., 2017). ...
Article
We evaluated a new integrated pest-management system for Anastrepha fraterculus (Wiedemann, 1830), the main insect pest of apple crops in Brazil. Our strategy combined mass trapping and application of toxic baits in crop systems without (Area 1) and with (Area 3) anti-hail netting. The treatments were compared with the conventional management (applications of toxic baits and insecticides as cover sprays) in two areas without (Area 2) and with (Area 4) anti-hail netting. The study was conducted for two consecutive years (2017–2018 and 2018–2019 seasons). In areas with mass trapping (Area 1 and Area 3), 120 PET traps (600 mL), baited with 300 mL of CeraTrap® hydrolyzed protein, were used per hectare. Fewer A. fraterculus adults were caught in crop systems without anti-hail netting using McPhail monitoring traps in Area 1 (mass trapping) than under conventional management (Area 2). The infestation of A. fraterculus was similar in areas with anti-hail netting with mass trapping (A3) and under conventional management (A4). In the 2017–2018 season, the areas with mass trapping (A1 and A3) had fewer damaged fruits (%) either without (0.4%) and with (0.7%) anti-hail netting than in the areas with conventional management (A2 and A4) without (1.7%) and with (0.8%) anti-hail netting. However, in the 2018–2019 season, fruit damage was similar in all areas studied. Mass trapping combined with the use of toxic baits can be an alternative to the conventional management of A. fraterculus.
... Future studies should directly compare infestations of A. fraterculus in areas with and without anti-hail netting, with the possibility of including one area as a true control, because previous studies have indicated that the nets can act as a physical barrier to pests, reducing the levels of infestation and damaged fruits (Lloyd et al., 2005;Tasin et al., 2008;Chouinard et al., 2017). This behavioral response was observed for Cydia pomonella Linnaeus (Lepidoptera: Tortricidae) in apple orchards in Italy, France and Canada. ...
... In these studies, in addition to functioning as a physical barrier, the net impaired the reproduction of the moths (Tasin et al., 2008;Sauphanor et al., 2012;Baiamonte et al., 2016;Chouinard et al., 2016). Lloyd et al. (2005) reported that the use of exclusion netting (2 × 2 mm mesh) in a totally closed system prevented the entry of Bactrocera tryoni Froggatt (Diptera: Tephritidae) into peach (Prunus persica) and nectarine (Prunus persica var. nucipersica) orchards in Australia. ...
... nucipersica) orchards in Australia. In that study, although seasonal peaks of the species were recorded in the adjacent plots, which had no netting, no damaged fruit were found in the orchards protected by netting (Lloyd et al., 2005). In Canada, the use of exclusion nets installed over each planting row down to ground level also significantly reduced the percentage of apple fruits damaged by Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) (Chouinard et al., 2017). ...
Article
We evaluated a new integrated pest-management system for Anastrepha fraterculus (Wiedemann, 1830), the main insect pest of apple crops in Brazil. Our strategy combined mass trapping and application of toxic baits in crop systems without (Area 1) and with (Area 3) anti-hail netting. The treatments were compared with the conventional management (applications of toxic baits and insecticides as cover sprays) in two areas without (Area 2) and with (Area 4) anti-hail netting. The study was conducted for two consecutive years (2017–2018 and 2018–2019 seasons). In areas with mass trapping (Area 1 and Area 3), 120 PET traps (600 mL), baited with 300 mL of CeraTrap® hydrolyzed protein, were used per hectare. Fewer A. fraterculus adults were caught in crop systems without anti-hail netting using McPhail monitoring traps in Area 1 (mass trapping) than under conventional management (Area 2). The infestation of A. fraterculus was similar in areas with anti-hail netting with mass trapping (A3) and under conventional management (A4). In the 2017–2018 season, the areas with mass trapping (A1 and A3) had fewer damaged fruits (%) either without (0.4%) and with (0.7%) anti-hail netting than in the areas with conventional management (A2 and A4) without (1.7%) and with (0.8%) anti-hail netting. However, in the 2018–2019 season, fruit damage was similar in all areas studied. Mass trapping combined with the use of toxic baits can be an alternative to the conventional management of A. fraterculus.
... In some cases, these are placed horizontally at a certain distance above the trees (Basile et al., 2008Corvalán et al., 2014;Lee et al., 2015;Lobos et al., 2013); whilst in others, peaked net structures are designed to allow hail to fall off the sloping surface of the net (Amarante et al., , 2011. Some farmers use nets to cover the whole orchard including the soil area (Baiamonte et al., 2016;Kelderer et al., 2010;Lloyd et al., 2005). Others still, cover specific rows of trees where nets are pegged to the ground (Baiamonte et al., 2016;Chouinard et al., 2017;Kelderer et al., 2010;Sauphanor et al., 2012;Ughini et al., 2008). ...
... It should be noted that research is needed to optimize netting systems to allow pollination in self-incompatible fruit tree species and cultivars. In some cases where nets were installed prior to pollination, bee hives were placed inside enclosures during the flowering period (Lloyd et al., 2005). ...
... Fruit flies Researchers studying exclusionary nets reported a decrease in fruit fly infestation and fruit damage in fruit trees (Table 6). Lloyd et al. (2005) reported that the use of exclusion netting (full enclosure -2 mm mesh) resulted in zero infestation on fruit: It decreased fruit fly entry into the enclosure. It is important to note that covering the entire canopy and sealing nets under the lower branches from the first fruit fly capture up until harvest inhibited oviposition more effectively than fixing the net to the soil (Ughini et al., 2008). ...
Article
Protected tree fruit cultivation using sustainable environmently-friendly practices is considered a promising alternative to meet the challenge of various biotic and abiotic stresses threatening fruit production under climate changes. Nowadays, nets are being globally used to protect the trees against harsh environmental conditions including hail, wind, excess sunlight and pests while improving tree health and enhancing fruit quality. Different types of nets including anti-hail, exclusion and photoselective nets have a different impact on the fruit tree response and production depending on their type, shading factor, mesh size, timing of display in the orchard and the netting system erected in the orchard. This review analyzes the effect of various types of nets on the microclimate, tree growth and management, fruit quality, diseases, disorders, economical insect pests and beneficial insects.
... Netting is being tested as an efficient way to protect crops against climate challenges i.e. excessive radiation (light and heat), hail, wind, and against biological challenges i.e. flying pests (insects, bats, birds) and in some cases diseases and to improve quality and yield. For a recent exhaustive review on the use of nets for Tree fruit crops and their impact on the production refer to Manja and Aoun (2019).Tests carried out on apple trees (Lawson et al., 1994;Aoun, 2016;Chouinard et al., 2017) and stone fruit trees (Erez et al., 1992;Lloyd et al., 2005) have demonstrated that various types of insect-proof nets can prevent the entry of a number of pests without drastically changing the environment and quality of the fruit produced under nets. A successful example covering large areas (more than 2500 ha in France) is the exclusion system called Alt'Carpo developed in France (Sévérac and Romet, 2007). ...
... The results showing reduction of fruit flies caught in traps under nets are in line with the ones reported by Lloyd et al. (2005) and confirm the ability of nets when used in an exclusion setting to significantly reduce pest populations (Candian et al., 2019). ...
... IPM typically involves a combination of sanitation practices (e.g., pruning and strip picking), biological controls (e.g., predatory beetles or parasitoid wasps), and the application of biopesticides (e.g., the entomopathogenic fungus Beauveria bassiana) [20][21][22][23][24]. Despite a good environmental profile and effectiveness against a wide variety of crop pests such as codling moth [25,26], tephritid flies [27][28][29], and brown-marmorated stinkbug [30,31], exclusion systems have not been examined as a potential IPM strategy for the protection of coffee crops against CBB. ...
... This view has gradually changed over the last two decades, as the search for sustainable alternatives to chemical controls is being increasingly driven by pesticide bans and public demand for organically grown food [37,38]. A growing body of research in recent years has shown that exclusion nets are effective in preventing or significantly reducing crop damage from various pests including insects [26][27][28][39][40][41][42], birds [43][44][45] and bats [46], as well as weather-related factors such as wind [47] and hail [48]. Additionally, exclusion nets modify the plant's growing environment and can have a number of positive effects on the physiology of the plant (e.g., reducing water stress by lowering evaporative demand, reducing heat stress by shading, and reducing light stress by improving the penetration of spectrally modified light into the canopy) [49][50][51][52]. ...
Article
Full-text available
Exclusion nets are increasingly being used to protect a variety of agricultural crops from insect pests as a sustainable alternative to chemical controls. We examined the efficacy of exclusion nets in controlling the world’s most damaging insect pest of coffee, Hypothenemus hampei (coffee berry borer), on two small-scale coffee farms on Hawai’i Island. We recorded microclimate data, fruit infestation, population per fruit, sex ratio, mortality by Beauveria bassiana, coffee yield and quality in four paired exclusion and control (un-netted) plots on both farms. Mean and maximum daily temperature and relative humidity were similar between treatments, while mean and maximum daily solar radiation was reduced by ~50% in exclusion plots. Green and ripe fruit from exclusion plots had significantly lower infestation compared to un-netted control plots at both farms. We observed no significant difference between exclusion and control plots in the number of CBB per fruit or the female:male sex ratio. CBB mortality was significantly higher in control relative to exclusion plots in one of the two farms. Ripe fruits harvested from exclusion plots were on average significantly heavier and wider than those from control plots; however, there was no significant difference in the average yield per tree between treatments. Lastly, coffee quality was not significantly different between control and exclusion plots. Our results suggest that with complete sanitation prior to net installation in an environment where CBB is actively circulating, exclusion netting can successfully control CBB on small-scale coffee farms without reducing coffee yield or quality, and has the potential to lower production and labor costs by eliminating the need to spray pesticides.
... Netting is being tested as an efficient way to protect crops against climate challenges i.e. excessive radiation (light and heat), hail, wind, and against biological challenges i.e. flying pests (insects, bats, birds) and in some cases diseases and to improve quality and yield. For a recent exhaustive review on the use of nets for Tree fruit crops and their impact on the production refer to Manja and Aoun (2019).Tests carried out on apple trees (Lawson et al., 1994;Aoun, 2016;Chouinard et al., 2017) and stone fruit trees (Erez et al., 1992;Lloyd et al., 2005) have demonstrated that various types of insect-proof nets can prevent the entry of a number of pests without drastically changing the environment and quality of the fruit produced under nets. A successful example covering large areas (more than 2500 ha in France) is the exclusion system called Alt'Carpo developed in France (Sévérac and Romet, 2007). ...
... The results showing reduction of fruit flies caught in traps under nets are in line with the ones reported by Lloyd et al. (2005) and confirm the ability of nets when used in an exclusion setting to significantly reduce pest populations (Candian et al., 2019). ...
Article
An assessment of a red photoselective netting system on apple production was conducted in a Mediterranean semi-arid climate. For two seasons, blocks of trees from an early bearing (cv Jonagold) and late bearing (cv Fuji) cultivars were covered to full canopy with red photoselective nets with 20% shading factor and an exclusion mesh size of 5.2 × 2.1 mm in an experimental orchard and compared to uncovered blocks of trees in the same orchard. The influence of nets on microclimate was assessed by measuring light intensity, Photosynthetic active radiation (PAR), Air temperature and relative humidity. An average decrease of 22.8% in light intensity along with a reduction in the average PAR radiation incidence by 23% improved the leaves photosynthesis efficiency with no influence on air temperature and relative humidity. The nets, installed after petal fall, had no significant influence on annual shoot growth and fruit set. At harvest, apples taken from netted trees were better graded than in the control in terms of both quality and quantity. Fruit weight, size and color blush were significantly higher in apples grown under nets compared to uncovered ones in both cultivars. While apple firmness was slightly lower under nets, no significant differences were reported in terms of sugar content and malic acid between both treatments. Nets significantly reduced the population of codling moth and the fruit damages caused by this pest without use of insecticides. Nets also decreased the amount of fruit fly caught in traps. No differences were recorded in terms of powdery mildew occurrence, aphids, mites and leafminer populations between both treatments. At last, nets also protected apples from sunburn and bird damages. To our knowledge, this is the first overall assessment of apple production in a pest-exclusion setting using red photoselective nets.
... This has gradually changed over the last three decades in tree fruit production, as nets have been increasingly used in many parts of the world to prevent damage from hail (Iglesias and Allegre, 2006) and even mammal and insect pests (Tasin et al., 2008). Various types of net coverings are now widely used for a range of horticultural crops in various countries around the world to provide protection from birds, frugivorous bats, hail, wind, frost and sunburn damage (Lloyd et al., 2005). Net enclosures are more and more used in organically grown fruit to solve several production issues (Granatstein et al., 2015), and are currently investigated as a potential solution to the devastating problems caused by the brown marmorated stink bug, Halyomorpha halys in the United States and many other parts of the world (Marshall and Beers, 2016). ...
... Chemical control of the Queensland fruit fly using cover and bait sprays is possible but expensive; often protection is incomplete unless many treatments (5-6) are applied annually. Lloyd et al. (2005) used a clear net exclosure (mesh size: 2 × 2 mm) in a high-pressure environment to demonstrate the efficacy of nets against this insect. Despite hundreds of captures weekly in the adjacent uncovered block, no damaged fruit was found following the examination of more than 700 fruits from the protected block. ...
... This has gradually changed over the last three decades in tree fruit production, as nets have been increasingly used in many parts of the world to prevent damage from hail (Iglesias and Allegre, 2006) and even mammal and insect pests (Tasin et al., 2008). Various types of net coverings are now widely used for a range of horticultural crops in various countries around the world to provide protection from birds, frugivorous bats, hail, wind, frost and sunburn damage (Lloyd et al., 2005). Net enclosures are more and more used in organically grown fruit to solve several production issues (Granatstein et al., 2015), and are currently investigated as a potential solution to the devastating problems caused by the brown marmorated stink bug, Halyomorpha halys in the United States and many other parts of the world (Marshall and Beers, 2016). ...
... Chemical control of the Queensland fruit fly using cover and bait sprays is possible but expensive; often protection is incomplete unless many treatments (5-6) are applied annually. Lloyd et al. (2005) used a clear net exclosure (mesh size: 2 × 2 mm) in a high-pressure environment to demonstrate the efficacy of nets against this insect. Despite hundreds of captures weekly in the adjacent uncovered block, no damaged fruit was found following the examination of more than 700 fruits from the protected block. ...
... This has gradually changed over the last three decades in tree fruit production, as nets have been increasingly used in many parts of the world to prevent damage from hail (Iglesias and Allegre, 2006) and even mammal and insect pests (Tasin et al., 2008). Various types of net coverings are now widely used for a range of horticultural crops in various countries around the world to provide protection from birds, frugivorous bats, hail, wind, frost and sunburn damage (Lloyd et al., 2005). Net enclosures are more and more used in organically grown fruit to solve several production issues (Granatstein et al., 2015), and are currently investigated as a potential solution to the devastating problems caused by the brown marmorated stink bug, Halyomorpha halys in the United States and many other parts of the world (Marshall and Beers, 2016). ...
... Chemical control of the Queensland fruit fly using cover and bait sprays is possible but expensive; often protection is incomplete unless many treatments (5-6) are applied annually. Lloyd et al. (2005) used a clear net exclosure (mesh size: 2 × 2 mm) in a high-pressure environment to demonstrate the efficacy of nets against this insect. Despite hundreds of captures weekly in the adjacent uncovered block, no damaged fruit was found following the examination of more than 700 fruits from the protected block. ...
Article
Full-text available
Because of their perennial nature, orchards harbor one of the most complex ecosystems in agriculture. Nevertheless, crop protection programs still mainly focus on pesticides (synthetic or organic-approved) to prevent or limit the action of so-called noxious species in these systems. Killing agents represent the dominant paradigm and have been used in agriculture for decades. This paper synthesizes the available literature about the other approaches, more suited to organic farming, which recognize that the radicalness of killing is not necessary to prevent crop losses. Exclusion barriers represent one of the most readily available means of protecting the crop that way, but other behavior-based techniques have been developed, such as sterile insect technique and mating disruption. While there are many other possibilities, these are the three approaches that are currently getting the most interest in tree fruit production, due to ecological and agronomical characteristics, some of which will be detailed in this review.
... Tree caging has long been evaluated experimentally to prevent the development of insect pests on fruit trees and to provide a low-chemical input fruit production system (Erez et al., 1993;Lawson et al., 1994). In Australia, a durable net fabric and support system to ensure exclusion of the fruit fly Bactrocera tryoni (Froggatt) is commercially available (Lloyd et al., 2005). Netting is also used for climatic protection to prevent wind or hailstorm damage (Middleton & McWaters, 2002;Iglesias & Alegre, 2006). ...
... This ability to pass through the two mesh sizes in the laboratory was confirmed by the release-capture experiments, in which a significant proportion of adults released inside the nets escaped and were captured in the control rows. Considering the requirement of completely closed systems (Lawson et al., 1994) or of a mesh size that strictly prevents pest entry (Lloyd et al., 2005), unsatisfying protection could be expected from the partial barrier offered by Alt'carpo nets to codling moth penetration. In the experimental orchard, both mesh sizes had roughly the same efficacy and did not completely prevent fruit injury. ...
Article
Insecticide‐based management programmes targeting codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae: Olethreutinae), in apple orchards in southern France have incurred increasing levels of fruit injury in recent years. An alternative programme incorporating the use of exclusion netting named Alt'carpo has been developed. This study aimed at studying its efficiency and gaining more insight into its mode of action. This was achieved through laboratory and field behavioural tests and observations in a network of commercial orchards in southern France. The moths were able to lay eggs through the nets and escape from net cages in the laboratory. Male moths released in the netted rows were poorly recaptured using sexual pheromone trapping, whereas over 20% of the released males were recaptured in unprotected rows. The netting reduced fruit injury by up to 91% compared to the unprotected rows in the experimental orchard. The efficacy of this netting was even higher in commercial orchards in which fruit injury did not exceed 0.1% without any application of specific insecticide. These results lead us to assume that netting alters the reproduction of the pest, mainly by preventing it from flying over the canopy to find mates.
... The application of nets on fruit trees can harm entomophilic pollination of fruit trees, and, thus, certain measures must be taken, such as the application of nets after the end of flowering, removal of parts of nets during flowering, or introduction of beehives during flowering in orchards protected by nets [7,58,110]. In addition, shading and high temperatures can also cause a reduction in fruit sets. ...
Article
Full-text available
Net application in agriculture has a long history. Nets were usually used for the protection of plants against different hazards (hail, wind, birds, pests, excessive sun radiation) and, lately, from insects (nets with smaller mesh size). In recent years, photoselective netting technology has emerged, which adds desired plant responses caused by light quality changes to their basic protective properties. A combination of anti-insect and photoselective net technology (anti-insect photoselective nets) may present a notable contribution to the sustainable food production concept. Notable positive effects of this eco-friendly approach on agroecosystems are mainly achievable due to its non-pesticide pest protection of cultivated plants and, at the same time, promotion of special beneficial morphological and physiological plant responses. Although netting has been extensively studied over the last decade, there is a pronounced lack of publications and analyses that deal with their mode of action on fruit trees, which is especially true for new netting concepts. A better understanding of such mechanisms can lead to improved development and/or utilization of this technology and enhanced generation of value-added products. This review was based on a revision of the literature regarding netting in agriculture, with emphasis on fruit cultivation, and the following databases were used: Web of Science, ScienceDirect, Scopus, and Google Scholar. Although this study aims to comprehend a majority of fruit species, it narrows down to those usually net-protected and, hence, studied, such as apple, peach or nectarine, kiwifruit, blueberry, etc. Nets mainly differ in their mesh size and color, which are the parameters that mostly determine their capacity for light quantity and quality modification. Such light modifications, directly or indirectly (e.g., change in microclimate), initiate different fruit tree responses (in some cases, mechanisms) through which the final effect is realized on their vegetative and generative traits. For instance, some of them include a shade avoidance mechanism (initiated by changes in red to a far-red ratio, blue light levels, etc.), source– sink relationship, and carbohydrate availability (actualized by changes in photosynthesis efficiency, vegetative and generative growth, etc.), plant stress response (actualized by microclimate changes), etc. In most cases, these responses are interconnected, which contributes to the complexity of this topic and emphasizes the importance of a better understanding of it.
... Pest exclusion nets have been developed as a non-aggressive barrier preventing pest access to crops and potentially disturbing the behavior of certain pest species (Alaphilippe et al. 2016). Netting systems are widely used to protect crops against frugivorous bats and birds, hail, wind, frost, and sunburn (Lloyd et al. 2005). Their efficiency has driven the global expansion of their use against a broad range of insect pests of horticultural and fruit crops, including Lepidoptera, Diptera, and Hemiptera (Chouinard et al. 2017;Marshall and Beers 2016), among which Rhagoletis cerasi (Brand et al. 2013) and psyllas (Romet et al. 2010). ...
Article
Full-text available
Agricultural intensification has led to dramatic declines in bird populations. In particular, the acknowledged role of synthetic pesticides on direct bird intoxication or food resource depletion urges us to seek alternative crop protection methods. Pest exclusion netting systems have recently gained popularity among fruit growers as an efficient means of reducing pest attacks, allowing their transition to organic farming. Single-row exclusion nets, which only cover fruit trees and leave uncovered both the inter-row grassy strips and the hedges, are increasingly being used in apple orchards of Southern Europe. However, net-induced effects on wildlife remain unknown. This study is the first to assess the impacts of single-row exclusion nets on breeding bird communities. We hypothesized that the exclusion net effects would be weaker than those associated with synthetic pesticide use, except for bird species that forage in the tree canopy. We monitored breeding bird abundance, and species richness in 46 commercial apple orchards managed using integrated pest management (IPM) or organic standards with or without exclusion nets. We counted 705 birds belonging to 32 different species. Total bird abundance, the number of observed species, and the Chao1 estimate of species richness were influenced by orchard management strategy. Breeding bird assemblages in organic orchards were as numerous and diverse in both the presence and absence of exclusion nets. In contrast, both bird abundance and species richness were significantly decreased in IPM orchards. The abundance and species richness of bird assemblages and the abundance of a few individual species also increased with the number of hedgerows bordering the orchards. Our results demonstrate that single-row netting systems for organic farming represent an effective pest control strategy with no significant impact on bird communities and highlight the importance of hedgerows along the orchards’ edges.
... Many agricultural crops traditionally grown in open fields are now being produced in covered environments (e.g., glasshouses, hail netting, and polytunnels; Fig. 1; Baudoin et al., 2017;Castilla, 2002;Cook and Calvin, 2005;Nordey et al., 2017;Reddy, 2016), as these systems can help growers to overcome the challenges associated with extreme weather, pests, pathogens, and contamination by foreign pollen (Amarante et al., 2011;Lloyd et al., 2005;Morison et al., 2000). By modifying the growing environment, covered systems can also enhance crop production by providing warmer conditions for precocious bud initiation (Renquist, 2005;Retamal-Salgado et al., 2015), and increasing fruit quality, yield (Mditshwa et al., 2019;Parks et al., 2019), and efficiency of water and fertilizer use through the capture and reuse of leachates (Grewal et al., 2011;van Kooten et al., 2006). ...
Article
Full-text available
Protective covers (i.e., glasshouses, netting enclosures, and polytunnels) are increasingly used in crop production to enhance crop quality, yield, and production efficiency. However, many protected crops require insect polli-nators to achieve optimal pollination and there is no consensus about how best to manage pollinators and crop pollination in these environments. We conducted a systematic literature review to synthesise knowledge about the effect of protective covers on pollinator health and pollination services and identified 290 relevant studies. Bees were the dominant taxon used in protected systems (90%), represented by eusocial bees (e.g., bumble bees (Bombus spp.), honey bees (Apis spp.), stingless bees (Apidae: Meliponini)) and solitary bees (e.g., Amegilla spp., Megachile spp., and Osmia spp.). Flies represented 9% of taxa and included Calliphoridae, Muscidae, and Syr-phidae. The remaining 1% of taxa was represented by Lepidoptera and Coleoptera. Of the studies that assessed pollination services, 96% indicate that pollinators were active on the crop and/or their visits resulted in improved fruit production compared with flowers not visited by insects (i.e., insect visits prevented, or flowers were self-or mechanically pollinated). Only 20% of studies evaluated pollinator health. Some taxa, such as mason or leafcutter bees, and bumble bees can function well in covered environments, but the effect of covers on pollinator health was negative in over 50% of the studies in which health was assessed. Negative effects included decreased reproduction, adult mortality, reduced forager activity, and increased disease prevalence. These effects may have occurred as a result of changes in temperature/humidity, light quality/quantity, pesticide exposure, and/or reduced access to food resources. Strategies reported to successfully enhance pollinator health and efficiency in covered systems include: careful selection of bee hive location to reduce heat stress and improve dispersal through the crop; increased floral diversity; deploying appropriate numbers of pollinators; and manipulation of flower physiology to increase attractiveness to pollinating insects. To improve and safeguard crop yields in pollinator dependent protected cropping systems, practitioners need to ensure that delivery of crop pollination services is compatible with suitable conditions for pollinator health.
... Net covers have shown to alter the exchange of radiation momentum and mass between the crop and the atmosphere hence modifying the crop microclimate (Lloyd et al., 2004). Net reduce the mixing of outside and inside air, hence effectively reduce loss of heat to the surrounding atmosphere, which leads to a temperature increase (Tanny et al., 2003). ...
Article
Full-text available
A low tunnel experiment at Toukh Protected Cultivation Site, Al-Qalyubia Governorate, Agricultural Research Center was performed in 2017 and 2018 seasons to investigate the influence of colored net covering on microclimate i.e., maximum and minimum air and soil temperatures, maximum and minimum relative humidity and average solar radiation, soil properties (moisture, bulk density, organic carbon, pH and nutrients availability of N. P. K) as well as on vegetative growth (plant length, number of leaves per plant, stem diameter, number of branches per plant, fresh and dry weight of plants), chemical component of leaves (chlorophyll reading, N, P and K) and yield (early and total) and its components (number of pods/plant, average pod weight, T.S.S. and fiber content in pods) of common bean plants. Seedlings of Paulista were transplanted on 15 th of August 2017 and 2018 seasons. Seven types of covering were used as treatments, divided into six net covering color i.e., white, yellow, red, blue, grey and black 40%, plus plastic transparent (low polyethylene tunnels 60-80 micron), compared with open field conditions. This investigation was arranged in randomized block design with three replicates. Results reflected that, generally, using colored net covering led to modify microclimate parameters and enhanced almost tested characters of soil properties, vegetative growth, component of leaves and yield and its components. Furthermore, white net cover followed by yellow net cover were the most suitable cover for increasing productivity and quality of common bean plants.
... Exclusion netting has also been used successfully against various fruit pests (Chouinard et al., 2017;Del Fava et al., 2017;Lloyd et al., 2005), but may also create favourable environmental conditions for other pests (e.g. aphids) and disease outbreaks depending on the timing of net installation and its shading effect on the canopy. ...
Chapter
Fruit orchards were one of the initial agroecosystems selected for testing the implementation of IPM to successfully combine biological control and selected pesticide applications. For a successful IPM programme it is essential to recognize that there is an interaction between pest populations and their natural enemies at the ecosystem-level, and that fruit orchards are in close contact and interaction with the surrounding environment. In this context, judicious and harmonious use of selective pesticides in combination with non-chemical tools and control tactics are expected to maintain the pest populations below EILs and to minimize the potential deleterious side effects of pesticides. Implementation of these ecological principles in an effective pest control strategy is often influenced by conflicting social interests. Increased public fears about the impact of pesticides such as the potential adverse effects on human health and overall environmental quality, promote the development of tools with lower risk factors. However, at the same time, high cosmetic standards for fresh fruit required by consumers represent formidable obstacles in the adoption of alternative pest control tools. While considering all these aspects, the resultant insect pest management strategy ‘should be based on cost/benefit analyses that take into account the interests of and impacts on producers, society and the environment’. This goal is, at least partially, achievable by avoiding unnecessary application of harmful products and by optimizing the unavoidable use of insecticides which should always be based on accurate information about the actual pest-beneficial insect equilibrium in fruit orchards
... Subsequent studies have shown how netting can interfere with the sexual activity and flight of CM (Tasin et al. 2008;Sauphanor et al. 2012;Ioriatti and Tasin 2018). The occurrence of nets in eastern Washington appears to be expanding rapidly due to this effect and to protect fruits from sunburn while enhancing tree physiology (Lloyd et al. 2005;Bastias et al. 2012). Unfortunately, the use of netting may exacerbate management of other pests such as aphids (Dib et al. 2010). ...
... In the case of the two aphid species, this may in part have been due to exclusion of natural enemies [66,67], although changes in microclimate under the netting may also have had an influence; a similar result was observed when fine mesh exclusion netting was used in high tunnels [68]. Exclusion netting has also been used on an experimental basis for managing various tephritid fruit flies attacking tree fruits, including European cherry fruit fly (Rhagoletis cerasi (L.) (Diptera: Tephritidae) in Europe [84] and Queensland fruit fly (Bactrocera tryoni (Froggatt)) (Diptera: Tephritidae) in Australia [85]. ...
Article
Full-text available
Small-scale farms are an important component of agricultural production even in developed economies, and have an acknowledged role in providing other biological and societal benefits, including the conservation of agricultural biodiversity and enhancement of local food security. Despite this, the small-farm sector is currently underserved in relation to the development and implementation of scale-appropriate Integrated Pest Management (IPM) practices that could help increase such benefits. This review details some of the characteristics of the small farm sectors in developed economies (with an emphasis on the USA and Europe), and identifies some of the characteristics of small farms and their operators that may favor the implementation of IPM. Some of the challenges and opportunities associated with increasing the uptake of IPM in the small-farm sector are discussed. For example, while some IPM tactics are equally applicable to virtually any scale of production, there are others that may be easier (or more cost-effective) to implement on a smaller scale. Conversely, there are approaches that have not been widely applied in small-scale production, but which nevertheless have potential for use in this sector. Examples of such tactics are discussed. Knowledge gaps and opportunities for increasing IPM outreach to small-scale producers are also identified.
... High-value crops, which were traditionally grown in the open, are increasingly produced under netting and/or plastic covers (Baudoin et al., 2017;Castilla, 2002;Cook & Calvin, 2005;Reddy, 2016). Crop covers are used to increase the reliability or duration of production by modifying the growing environment and to enhance crop quality and yields by providing a physical safeguard against extreme weather, plant pests, and pathogens (Amarante, Steffens, & Argenta, 2011;Lloyd, Hamacek, George, Nissen, & Waite, 2005;Marco et al., 2008;Middleton & McWaters, 1997;Sauphanor, Severac, Maugin, Toubon, & Capowiez, 2012). For crops grown for seed production, covers can prevent foreign pollen contamination, which can cause reduced yields or undesirable hybrids (Morison, Vaissiere, Martin, Pecaut, & Cambon, 2000;Rodet, Torre Grossa, & Bonnet, 1991). ...
Article
Full-text available
The widespread use of protective covers in horticulture represents a novel landscape‐level change, presenting the challenges for crop pollination. Honeybees (Apis mellifera L) are pollinators of many crops, but their behavior can be affected by conditions under covers. To determine how netting crop covers can affect honeybee foraging dynamics, colony health, and pollination services, we assessed the performance of 52 nucleus honeybee colonies in five covered and six uncovered kiwifruit orchards. Colony strength was estimated pre‐ and postintroduction, and the foraging of individual bees (including pollen, nectar, and naïve foragers) was monitored in a subset of the hives fitted with RFID readers. Simultaneously, we evaluated pollination effectiveness by measuring flower visitation rates and the number of seeds produced after single honeybee visits. Honeybee colonies under cover exhibited both an acute loss of foragers and changes in the behavior of successful foragers. Under cover, bees were roughly three times less likely to return after their first trip outside the hive. Consequently, the number of adult bees in hives declined at a faster rate in these orchards, with colonies losing on average 1,057 ± 274 of their bees in under two weeks. Bees that did forage under cover completed fewer trips provisioning their colony, failing to reenter after a few short‐duration trips. These effects are likely to have implications for colony health and productivity. We also found that bee density (bees/thousand flowers) and visitation rates to flowers were lower under cover; however, we did not detect a resultant change in pollination. Our findings highlight the need for environment‐specific management techniques for pollinators. Improving honeybee orientation under covers and increasing our understanding of the effects of covers on bee nutrition and brood rearing should be primary objectives for maintaining colonies and potentially improving pollination in these systems.
... However, the effect has been obtained with a predator:prey ratio of 1:1 or 5:1 (Wyss et al. 1999), compromising the cost-efficiency of the method. So, further studies are needed, possibly exploiting codling moth exclusion nets, which are of extended use due to their side effects on fruit quality and orchard microclimate (Lloyd et al. 2005;Baiamonte et al. 2016), as a physical barrier to increase the efficiency of the releases (Dib et al. 2016a). Mummified aphids were found to be more efficient to release Aphidius ervi (Haliday) than adult parasitoids (Wei et al. 2005). ...
Article
Apple and peach orchards are chemical-intensive systems, and aphids are one of their major pests. Aphids alter fruiting and shoot development, and they can spread viruses. Decades of insecticide use have developed aphid resistance, which calls on research to provide alternatives to chemicals for pest management. Here, we review the literature to identify, for each stage of the aphid life cycle, existing alternatives based on either top-down (i.e. aphid predation or parasitism) or bottom up (i.e. increase of host plant resistance) processes. Firstly, it was found that most studies focus on top-down processes, namely on conservation biological control aiming to preserve existing populations of natural enemies: predators, parasitoids and nematodes. This is achieved by (i) providing shelters (i.e. planting hedges, weed or flower strips) or alternative preys in periods of aphid scarcity or (ii) choosing chemicals with the lowest disruptive effects. Those methods prove more efficient when used early in the season, i.e. before the exponential increase of aphid populations. Fostering the complex of natural enemies is also preferable than just supporting one single enemy. Secondly, other techniques, like (i) releasing biological control agents (entomopathogenic fungi, nematodes) or (ii) using pheromone lures to prevent autumnal sexual reproduction, are currently adapted for their use in orchard conditions. Thirdly, bottom-up regulation has to be devised as a long-term strategy, which could start by choosing a cultivar enabling genetic avoidance or developing genetic resistance. Then, aphid development can be reduced by the control of shoot growth or nitrogen accumulation in response to pruning or moderate water and nutrient inputs. At last, autumnal return of aphids could be disrupted by techniques such as kaolin applications that impair aphid host plant location. It is concluded that these alternative methods have to be adapted to local conditions and combined in long-term strategies in order to decrease the infestation risks throughout the orchard lifespan.
... According to Markow and Grady (2008), reproductive maturation of D. Another preventative approach involves the deployment of fine mesh netting at ripening and pre-harvest crop intervals as a physical hindrance to ovipositing D. suzukii contacting potential host fruits. This technique has been effectively implemented in IPM programs for a variety of insect pests (Lloyd et al. 2005, Dib et al. 2010, Sauphanor et al. 2012, and has received attention in the ongoing efforts to provide organic growers with chemical management alternatives for SWD in a variety of agricultural systems (Schattman 2015, Cormier et al. 2015. The works of Cormier et al. (2015) also addressed the significance of net-shading on plant photosynthetic activity by quantifying the chlorophyll and sugar composition of blueberry fruits upon concluding the study. ...
Article
Full-text available
This research was conducted in order to identify the potential for utilization of various management techniques against the invasive Drosophila suzukii Matsumura, commonly referred to as the spotted wing drosophila (SWD), using Maine lowbush blueberry (Vaccinium angustifolium Aiton) as a model crop system. These included evaluations of three prospective approaches often considered when developing agricultural pest management programs for novel insect pests: 1) biological control through the intended release of natural enemies, in this case entomopathogenic fungi; 2) behavioral management through mass trap deployment in order to capture and kill adult SWD, and; 3) prevention through the deployment of insect exclusion netting during the pre-harvest fruit ripening period. The first assessment was accomplished through complementary laboratory and field experiments. Mass-inoculation laboratory assays with four species of fungi resulted in significant mortality of SWD flies over five days post-exposure (P < 0.0001). While both Beauveria bassiana (strain GHA) and Metarhizium anisopliae (strain F-52) were among the most lethal isolates, only B. bassiana mycoses were shown to exert a significant dose-mortality response over a three day period following initial contact with conidia (P < 0.0001); based on the data obtained, the derived LC­­50 value corresponded to a pathogen surface density of approximately 16,000 conidia mm-2. Although no detectable mortality effect was found during the M. anisopliae assay (P = 0.64), the frequency of sporulating fly cadavers increased substantially at elevated conidia doses of either fungal pathogen (P < 0.0001). A sub-lethal assessment of B. bassiana mycosis on reproductive development in immature D. suzukii females also generated support for decreased oocyte maturation rates in individual flies (P = 0.02). Coupled with the observable germination of conidia through SEM imaging, these results provide strong evidence for positive infection under laboratory conditions. Despite these promising results, however, the subsequent field evaluation of a commercially available B. bassiana (strain GHA) containing myco-insecticide yielded no additional evidence that could justify these entomopathogens as being feasible biocontrol agents in SWD management. Spraying blueberry enclosures prior to the introduction of 2,000 adult SWD failed to reduce the quantity of larvae inhabiting fruit samples, with 59 ± 63 (SD) vs 28 ± 19 obtained in sprayed vs unsprayed plots, respectively. Objectives two and three entailed field experimentation only with lowbush blueberry. Mass trapping with volatile semiochemicals was evaluated at different trap concentrations. Varying the spatial arrangement of traps within study grids significantly influenced the quantity of SWD larvae infesting sampled blueberry fruits (P = 0.0003). The trap design and bait tested here were most effective when deployed at the lowest density (0.9 m trap spacing). Fruit samples collected from crops provided this treatment contained mean larval infestations of 1.5 ± 1.8 (SD). For comparison, the deployment of traps with 1.8 and 2.7 m of trap spacing resulted in larval sampling averages of 8.8 ± 11.1 (SD) and 17.3 ± 13.7, respectively. However, there was no detectable treatment effect of trap spacing on the mean number of adults captured in traps (P =0.40). The results of this field investigation, in conjunction with those of other studies, might justify additional research on trap cropping in order to reduce the overall degree of chemical inputs required to adequately suppress fruit infestation. The final objective produced results consistent with those of analogous investigations, which have shown insect-netting to be an effective preventative agent for physical exclusion of SWD flies from contacting viable host fruits prior to harvest intervals. Studies conducted in the lowbush blueberry agroecosystem during summer of 2014 and 2015 provide further support for this conclusion; net-protected fruits contained an average of 0.2 ± 0.2 (SD) larvae, in comparison to uncovered control fruits in which an average of 5.2 ± 3.9 larvae were sampled (P < 0.0001). In order to confidently implement novel management techniques for suppressing SWD infestations, the observations gathered in this assessment cannot justify the immediate utilization of any technique as a replacement for insecticidal treatments. Even the positive results obtained from insect-netting experiments were constrained by limitations of spatial practicality with respect to application in large scale fruit growing operations. Therefore, additional experimentation will be necessary before identifying any of these techniques as viable approaches to incorporate with developing integrated pest management programs.
... A greater microclimate modification was also obtained by maintaining the agronets permanently covered than when they were opened thrice a week for ventilation. The existence of a screen has been shown to alter the exchange of radiation, momentum and mass between the crop and the atmosphere hence modifying the crop microclimate (Lloyd et al., 2005). Screens reduce the mixing of outside air with inside air thus reduce heat loss to the surrounding atmosphere, which leads to a temperature build up (Tanny et al., 2003). ...
Article
Full-text available
Tomato (Solanum lycopersicum L.) is an important vegetable for supplying vitamins, minerals and fiber in human diets worldwide. Successful open field production of tomato in the tropics is limited by insect pests among other constraints. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya with the objective of evaluating the effects of agricultural nets (agronets) herein called eco-friendly nets (EFNs) and floating row covers (FRCs) on pest population and yield of tomatoes. A randomized complete block design with five replications was used. Tomato plants were protected with either fine mesh EFN (0.4-mm pore diameter), large mesh EFN (0.9-mm pore diameter) or FRC. The EFN and FRC were maintained permanently closed or opened thrice a week from 9 am to 3 pm. Two control treatments were used: open unsprayed (untreated control) or open and sprayed with alpha-cypermethrin based insecticide (treated control). The use of EFN and FRC helped to manage pests with the lowest pest population obtained under FRC maintained permanently covered and the highest population recorded in the untreated control. Covering tomato plants with EFN or FRC also resulted in more marketable fruit and lower yield losses compared with the unprotected systems. The EFN and FRC offer great potential as part of integrated systems for pest management and yield improvement in tomato production in regions with a tropical climate.
... In order to support organic growers who do not use insecticides, exclusion nets were seen, in our ara, as a D. suzukii control method in blueberry production. Exclusion nets are used to protect fruits and vegetables from pests in Europe and North America (Murphy & Ferguson, 2000;Lloyd et al., 2005;Dib et al., 2010;Sauphanor et al., 2012). The use of exclusion netting to protect crops against the SWD has not been evaluated since the first record of the pest in North America, while this method is cited as a means of physical control against SWD adults (Dreves & Langellotto-Rhodaback, 2011;Cini et al., 2012). ...
Article
Full-text available
In 2012, the populations of spotted wing drosophila, Drosophila suzukii, caused high levels of damage in soft fruit production in Quebec, Canada. In an organic blueberry field, we tested exclusion nets as a physical control method against D. suzukii adults. Exclusion nets were compared with insecticide treatments and control. Baited traps were placed to catch D. suzukii adults and blueberries were harvested regularly to evaluate different parameters. No D. suzukii adults were collected from traps and blueberries of the exclusion net treatment. However, adults were caught in traps and infested blueberries outside the nets. Nets had no significant effect on sugar content, yield and damage from other pests. Blueberries harvested inside the nets were significantly larger than blueberries from control plots. The results for this first year demonstrate the effectiveness of exclusion nets to protect blueberry plants from D. suzukii infestations.
... A greater microclimate modification was also obtained by maintaining the agronets permanently covered than when they were opened thrice a week for ventilation. The existence of a screen has been shown to alter the exchange of radiation, momentum and mass between the crop and the atmosphere hence modifying the crop microclimate (Lloyd et al., 2005). Screens reduce the mixing of outside air with inside air thus reduce heat loss to the surrounding atmosphere, which leads to a temperature build up (Tanny et al., 2003). ...
Article
Full-text available
Adverse environmental conditions have contributed to perpetual poor cabbage (Brassica oleraceae var. capitata) yields in sub-Saharan Africa. Elsewhere, net covers have been reported to provide a low-cost technology with the potential of modifying the microclimate around a crop for better performance. Two experiments were therefore conducted over a span of two seasons to determine the effects of agronet covers on microclimate modification and subsequent cabbage yield and quality. The treatments comprised cabbage plants grown under either fine mesh (0.4 mm pore diameter) or large mesh (0.9 mm pore diameter) agronet covers maintained permanently closed, or opened thrice weekly from 9 am to 3 pm and a control treatment where cabbage was grown in the open field. Net covering generally modified the microclimate by raising temperatures, relative humidity and volumetric water content but lowering photosynthetic active radiation and diurnal temperature range compared to control. The use of agronet covers resulted in better cabbage performance. The large mesh (0.9 mm) enhanced leaf stomatal conductance and chlorophyll content, and improved fresh and dry weight as well as head quality. Results of this study present the use of agronet covers as a potentially effective technology for use by small-scale farmers in protected cabbage culture in sub-Saharan Africa.
... Air temperatures were on average increased by 10%, relative humidity by 4%, and soil moisture by 20% after the use of either treated or untreated agronet covers. Screen covers have shown to alter the exchange of radiation momentum and mass between the crop and the atmosphere hence modifying the crop microclimate (Lloyd et al., 2004). Screens reduce the mixing of outside and inside air, hence effectively reducing loss of heat to the surrounding atmosphere, which leads to a temperature increase (Tanny et al., 2003). ...
Article
Full-text available
French bean [Phaseolus vulgaris (L.)] is among the leading export vegetable in Africa, mostly produced by small-scale farmers. Unfavorable environmental conditions and heavy infestations by insect pests are among the major constraints limiting production of the crop. Most French bean producers grow their crop in open fields outdoors subject to harsh environmental conditions and repeatedly spray insecticides in a bid to realize high yield. This has led to rejection of some of the produce at the export market as a result of stringent limits on maximum residue levels. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya, to evaluate the potential of using agricultural nets (herein referred to as agronets) to improve the microclimate, reduce pest infestation, and increase the yield and quality of French bean. A randomized complete block design with five replications was used. French bean seeds were direct-seeded, sprayed with an alpha-cypermethrin-based insecticide (control), covered with a treated agronet (0.9 mm × 0.7 mm average pore size made of 100 denier yarn knitted into a mesh impregnated with alpha-cypermethrin), or covered with an untreated-agronet (0.9 mm × 0.7 mm average pore size made of 100 denier yarn knitted into a mesh not impregnated with insecticide). Alpha-cypermethrin and agronets were manufactured by Tagros Chemicals (India) and A to Z Textile Mills (Tanzania), respectively. Covering French bean with the agronets modified the microclimate of the growing crop with air temperature increased by ≈10%, relative humidity by 4%, and soil moisture by 20%, whereas photosynthetic active radiation (PAR) and daily light integral (DLI) were decreased by ≈1% and 11.5%, respectively. Populations of silverleaf whitefly [Bemisia tabaci (Gennadius)] and black bean aphids [Aphis fabae (Scopoli)] were reduced under agronet covers as contrasted with control plots. Furthermore, populations of both pests were reduced on French bean grown under impregnated agronets compared with untreated agronets, but only on three of the five sampling dates [30, 44, and 72 days after planting (DAP)] for silver leaf whitefly or at only one of the five sampling dates (30 DAP) for black bean aphid. Covering French bean with agronets advanced seedling emergence by 2 days and increased seedling emergence over 90% compared with control plots. French bean plants covered with both agronet treatments had faster development, better pod yield, and quality compared with the uncovered plants. These findings demonstrate the potential of agronets in improving French bean performance while minimizing the number of insecticide sprays within the crop cycle, which could lead to less rejection of produce in the export market and improved environmental quality. © 2012, American Society for Horticultural Science. All rights reserved.
Article
High-density production has been increasing for numerous perennial crops in different parts of the world. Recent work suggests that high-density systems improve yields, fruit quality, and harvest efficiency. Yet, despite the increasing amount of acreage in high-density production, there has been surprisingly little comparative research on pest and disease patterns in such systems compared to conventional systems. Given the significantly different structure of high-density plantings compared to conventional orchards, pest abundance, disease prevalence, and appropriate management strategies are likely to differ. Here we describe the characteristics of high-density plantings and how their management and infrastructure are likely to have direct and indirect effects on pest abundance and disease prevalence. We also describe how high-density structure, management, infrastructure, fruit abundance, and microclimate present challenges and opportunities for pest and disease management strategies. For example, the compact structure of high-density plantings may mean smaller quantities of inputs are required while, at the same time, the high foliage density may reduce penetration of pesticide sprays and other inputs. Finally, we propose critical areas for future research including 1) patterns of pest and disease prevalence among rootstocks and varieties, 2) how infrastructure and timing of high-density management affect pest and disease prevalence, 3) how microclimate and fruit abundance vary across canopy levels, with associated impacts on pest and disease prevalence, and 4) types of pest and disease management that are likely to be effective in high-density systems.
Article
Full-text available
Tomato plants are highly sensitive to chilling stress so this experiment was conducted during successive winter seasons of 2020/2021 and 2021/2022 to investigate the possibility of sustaining production and quality of tomato yield under cold conditions by using different types of mesh cover for low tunnels. Two commercial cultivars, i.e., Super gold F1 and Super streen F1 were used. Seedlings were transplanted under different types of mesh cover for low tunnels. Three types of mesh cover (63%, 65%, 73%) had done to cover the plants of all tested seasons compared to open field condition (control "Without cover"). Results show that significant differences were observed among the two hybrid varieties of tomato studied, in terms of their vegetative growth characteristics (plant height, number of branches, number of leaves, fresh weight, dry weight and leaves area) as well as yield and fruit quality characteristics (Fruit set, total yield, firmness, T.S.S and Vit. C. ‘Super gold’ exhibited significantly higher values for these characteristics, compared to ‘Super strain B’. Chilling reduced the growth parameters (plant height, number of leaves, number of branches, plant fresh weight, plant dry weight) for control plants (without cover) compared to the coverage treatments (63%, 65%, 73%). Significant highest results in the growth, chemical composition of tomato leaves as well as yield and fruit quality parameters were obtained with covering tomato plants by white mesh cover 63% flowed by 65% of treatments which were best than the chilled plants. Concerning the interaction between hybrid varieties and covering treatments, it can be noticed that Cv. Super gold F1 which grown under white mesh cover 63% recorded a highly significant increases in plant height, number of branches, number of leaves, fresh weight, dry weight, leaves area, N, P, K, total chlorophyll, total proline, total sugers contents, fruit set, total yield, firmness, T.S.S and Vit. C. when compared to Cv. Super streen B F1 which grown in open field (without coverage).
Article
Sustainable management of invasive arthropod pests requires insecticide-alternative, integrated strategies, such as protected culture. During 2016–2017, we studied the efficacy of exclusion netting at reducing infestation damage in fall-bearing raspberries caused by an invasive vinegar fly, Drosophila suzukii Matsumura. In an effort to manage outbreak infestation, we studied the efficacy of baited attracticidal spheres in netted and open plots. We also monitored the effects of netting on fruit marketability, abiotic conditions near the fruiting zone, and pollination effects due to exclusion. The results showed that while 80 g HDPE netting sufficiently deterred D. suzukii infestation early in the season, late-season infestation was often greater in netted zones compared to insecticide-treated open plots. The introduction of baited attracticidal spheres under the netting did not consistently reduce infestation, and in some cases even increased infestation late in the season, likely due to the presence of the olfactory bait. During both test years, fruit marketability was greater in netted plots compared with open plots, and in open plots, we observed more overripe fruit and additional feeding damage caused by other herbivores. However, the incidence of crumbly berry was higher in netted plots, indicating pollination deficits. Supplemental pollination appeared to reduce these effects. Although temperature did not differ significantly between netted and open plots, we also observed greater incidence of botrytis infection in netted plots containing attracticidal spheres, which was not present in netted plots alone. These data suggest that while exclusion netting may be a valuable tool for D. suzukii pest management, unless outbreak infestation under the netting and supplementation pollination are addressed, significant challenges may impede large scale implementation.
Article
The use of exclusion netting as an Integrated Pest Management technique is likely to become increasingly important as a means to increasing crop yields whilst minimising pesticide use. However, the increasing use of these nets will also lead to a rise in greenhouse gas emissions in the agricultural sector and pose problems related to their end-of-life disposal. Employing biopolymers made from low-carbon and renewable biomass feedstock to fabricate exclusion nets can potentially resolve these issues by merging the benefits of the two emerging technologies. Despite this, there has only been limited work on the use of biopolymer netting in agriculture. By looking at the challenges needed to be overcome for biopolymers to be widely used as a netting material, this review aims to bridge the gaps between the two fields of research. To do so, the past work done on agricultural netting is discussed, with a focus on the implemented materials and their desired properties. After this, potential candidate biopolymers for manufacturing agricultural nets are pointed out, emphasising their sustainability with respect to widely used Life Cycle Analysis (LCA) parameters, including the end-of-life treatment.
Article
Following the loss of two key pesticides, dimethoate and fenthion, producers and regulators need to develop new fruit fly management options. A systems approach is a likely measure in the post dimethoate and fenthion era. The risk of fruit fly can be mitigated at the regional, district and farm level. Some measures such as awareness and exclusion are common across all three levels. Pest control measures will be based on an understanding of climate, biology and pesticides. In this present paper, 28 different risk mitigation options that can be used in a systems approach in Australia are discussed.
Chapter
Organic horticulture has doubled from 2003 to 2013 in response to increasing demand for organic fruits and vegetables. The number of scientific studies investigating this research field has tripled from 1994 to 2013. This reflects the existence of policy support for organic horticulture as well as government and industry funding for research. Yields of organic fruit and vegetable farming systems can reach on average 89-102% of conventional yields. The environmental benefits of organic farming are well documented for biodiversity and for water and soil conservation. However, limited seed and plant materials have been developed for organic farming. One of the remaining challenges in production is to achieve a balanced nutrient composition of organic amendments and a timely nutrient release with plant nutrient uptake. Another major barrier for the expansion of organic horticulture is related to limited effective tools for pest, disease, and weed management. Although new biological control agents and biopesticides have been proposed in response to the alarming resistance to synthetic pesticides, additional plant protection research is needed. Beyond the fact that the health benefits of organic foods are controversial, organic fruits and vegetables have lower nitrate content and pesticide residues, and their vitamin C and phenolic compounds are often higher than conventional ones. However, few studies have dealt with strategies that promote or impair microbiological food safety. This is the case despite the proximity of edible plants with animal manure together with limited tools for organic farming to prevent microbial pre- and postharvest proliferation. The aim of this chapter was threefold: to draw a picture of the current situation of organic fruit and vegetable production in the world, to present the development of research related to this sector since the past 40 years, and to highlight the benefits and constraints of this production system, emphasizing nutritive value and microbiological food safety. In conclusion, key research areas are proposed to support the development of organic horticulture by increasing its resilience and security.
Article
D’invention récente (2005), les filets Altcarpo, une toile insect-proof recouvrant soit chaque rangée (« mono-rang ») soit la parcelle de pommiers (« mono-parcelle »), représentent une des rares alternatives permettant de diminuer les indices de fréquence de traitement en verger de pommiers, une des cultures les plus traitées en France. Le but du présent projet était de valider l’efficacité et d’étudier la durabilité de cette innovation. Sur le plan agronomique, les résultats de ce projet confirment la grande efficacité des filets de type « mono-rang » contre le carpocapse des pommes, le principal ravageur des pommiers. Cela permet une réduction significative des IFT dans les vergers conduits en Agriculture Biologique (-40%), la réduction, pour les vergers PFI, ne concerne que l’IFT insecticide. En terme de mécanisme d’action, les acquis de ce projet établissent que les filets représentent une double barrière, d’abord physique, en limitant le nombre de carpocapse pouvant atteindre les pommiers et ensuite comportementale, en réduisant significativement le nombre d’accouplements sous les filets. Cependant, dans le cas des filets « mono-parcelle », nous observons que certaines populations de carpocapse parvenaient à s’adapter. Nos études ont également pu mettre en évidence une modification significative mais limitée du microclimat (+0.7°C et -10% du PAR). Cependant aucune modification significative de la croissance des arbres ou de leur architecture et corrélativement de la qualité des fruits ou du rendement n’a été observée. Lorsque l’on élargit la focale aux autres ravageurs et maladies ou au cortège d’auxiliaires associés, nos études concluent que la présence de filets peut parfois s’accompagner d’une recrudescence d’attaques de pucerons (cendrés ou lanigères) sans atteindre des niveaux inquiétants. Ces recrudescences peuvent s’expliquer par (i) une réduction de l’usage des insecticides, (ii) une modification du cortège des auxiliaires (les filets limitent la présence des coccinelles et dans certaines conditions des syrphes) ou (iii) éventuellement des effets microclimatiques. On note également que la maille des filets actuels n’est pas efficace contre d’autres lépidoptères comme la tordeuse orientale du pêcher ou la tordeuse de la pelure. En matière d’impacts environnementaux, les filets, en diminuant les IFT autorisent des abondances supérieures de certains communautés d’auxiliaires, comme les forficules (en vergers PFI) ou les araignées (quel que soit le mode de protection phytosanitaire). Leur présence augmente également significativement la diversité des araignées de la canopée. Enfin, des études ex-ante ont été rendues possibles grâce au développement de l’outil « DEXI-pomefruit » afin d’évaluer la durabilité et l’efficience environnementale des filets. Sur ce dernier point, nos résultats indiquent que la durabilité globale des vergers couverts de filets Alt’carpo est bien supérieure aux vergers non couverts. Ceci est notamment due (i) à une meilleure durabilité économique (le surcoût lié à l’investissement pour la mise en place de filets est moins pénalisant que l’augmentation du risque de perte de récolte lorsque les vergers sont non couverts, les filets Alt’carpo sont également des filets para-grêle) et (ii) une meilleure durabilité environnementale liée à un moindre usage des pesticides. En conclusion, les filets représentent une alternative efficace dans la lutte contre le principal ravageur en verger de pommiers et permettent des réductions sensibles des IFT sans risque majeur concernant le développement d’autres ravageurs ou maladies. En matière de préconisation, nous concluons qu’en l’état des connaissances actuelles, les filets « mono-rang » semblent une solution plus efficace et plus durable que les filets « mono-parcelle
Article
A revised engineered barrier system model has been developed by the Electric Power Research Institute to predict the time dependence of the failure of the drip shields and waste packages in the proposed Yucca Mountain repository. The revised model is based on new information on various corrosion processes developed by the US Department of Energy and others and for a 20-mm-thick waste package design with a double closure lid system. As with earlier versions of the corrosion model, the new EBSCOM code produces a best-estimate of the failure times of the various barriers. The model predicts that only 15% of waste packages will fail within a period of 1 million years. The times for the first corrosion failures are 40,000 years, 336,000 years, and 375,000 years for the drip shield, waste package, and combination of drip shield and the associated waste package, respectively.
ResearchGate has not been able to resolve any references for this publication.