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Many rhizospheric bacterial strains possess plant growth-promoting mechanisms. These bacteria can be applied as biofertilizers in agriculture and forestry, enhancing crop yields. Bacterial biofertilizers can improve plant growth through several different mechanisms: (i) the synthesis of plant nutrients or phytohormones, which can be absorbed by plants, (ii) the mobilization of soil compounds, making them available for the plant to be used as nutrients, (iii) the protection of plants under stressful conditions, thereby counteracting the negative impacts of stress, or (iv) defense against plant pathogens, reducing plant diseases or death. Several plant growth-promoting rhizobacteria (PGPR) have been used worldwide for many years as biofertilizers, contributing to increasing crop yields and soil fertility and hence having the potential to contribute to more sustainable agriculture and forestry. The technologies for the production and application of bacterial inocula are under constant development and improvement and the bacterial-based biofertilizer market is growing steadily. Nevertheless, the production and application of these products is heterogeneous among the different countries in the world. This review summarizes the main bacterial mechanisms for improving crop yields, reviews the existing technologies for the manufacture and application of beneficial bacteria in the field, and recapitulates the status of the microbe-based inoculants in World Markets.
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... When it comes to boosting plant growth and nutrient availability, biofertilizers are among the most promising solutions. Recently, its application has grown throughout several places in the Arab world thanks to the incorporation of helpful and effective microorganisms, which are used as bacterial or fungal fertilizers, or both [2]. ...
... The second variable is the use of organic fertilizers (sheep dung), with OM0 indicating no application, OM1 indicating 20 Meg.ha-1, and OM2 indicating 40 Meg.ha-1. The properties of the fertilizer applied are listed in Table (2). Finally, spraying with manganese at three different concentrations (Mn0 = 0 mg. ...
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In order to investigate the impact of biological and organic fertilizer and manganese spraying, as well as the interaction between these factors, on the readiness and concentration of some elements in the soil and wheat plants (Barcelona variety), a field experiment was conducted in the Tafail area/Al Sahlan village, located 25 kilometers south of the center of Al Hilla/Babil Governorate, during the 2022-2023 agricultural season. All of the features of the investigated were impacted by biofertilization and organic fertilization, however spraying treatment with manganese at a dosage of (80 mg. L-1) was particularly effective at raising element concentrations in the plant.
... Using biofertilizers improves crop yields by increasing nutrient density and energy compounds. As an alternative, they are thought to be effective in increasing the availability of nutrients and promoting plant development [2,3]. When it comes to biofertilizer technology, bacterial inoculants like 2 Azospirillum spp. ...
... The results obtained from Tables (2,3,4,5) indicate that the addition of Azotobacter and Azospirillum bacteria to the soil led to a significant increase in certain soil properties, namely electrical conductivity, cation exchange capacity, bulk density, and organic matter content. This increase can be attributed to the role of microorganisms in sustaining live microbial biomass in the soil, which is considered part of modern soil management systems, particularly in soils subjected to continuous plant cultivation or excessive use of mineral fertilizers and pesticides, resulting in organic matter depletion [14]. ...
Conference Paper
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The experiment was conducted in the Al-Azawiya area, which is part of the Al-Musayib project in Babil Governorate, for the winter agricultural season of 2023 to study the impact of biofertilization, organic fertilization, and foliar boron spray on certain soil properties using a factorial experiment design according to Randomized Complete Block Design (R.C.B.D) and with three replications randomly distributed within three sectors, totaling 18 treatments to make the number of experimental units 54, The experiment included three factors. The first factor was biofertilization (seed inoculation) with a mixture of Azotobacter and Azospirillum bacteria at two levels (without inoculation, inoculation). The second factor was organic fertilization (sheep manure) applied to the soil at three levels (0, 10, 20) Mg ha-1. The third factor was boron foliar spray using boric acid at three levels (0, 5, 10) mg L-1. The means of treatments were compared using the Least Significant Difference (LSD) test at a probability level of (0.05). The results of the experiment indicated that the addition of biofertilizer and organic fertilizer resulted in significant differences in soil properties after cultivation (electrical conductivity, cation exchange capacity, bulk density, organic matter). However, foliar boron spray did not result in significant differences in soil properties after cultivation. The interaction between biofertilizer (seed inoculation) and organic fertilizer (20 Mg ha-1) also resulted in significant differences in soil properties after cultivation (electrical conductivity, cation exchange capacity, bulk density, organic matter). However, the interactions between biofertilizer (seed inoculation) and foliar boron spray, organic fertilizer, and foliar boron spray did not result in significant differences in soil properties after cultivation. Similarly, the triple interactions between biofertilizer (seed inoculation), organic fertilizer, and foliar boron spray did not result in significant differences in soil properties after cultivation.
... improve nutrient availability and stimulate plant growth [2]. Azospirillum spp bacteria are among the most important bacterial inoculants used in biofertilizer technology. ...
... Regarding the triple interaction between biofertilizer, organic fertilization, and boron, the treatment with biofertilizer + 20 Mg ha -1 + 10 mg L -1 significantly outperformed and yielded the highest mean of 10.15 Mg ha -1 compared to the untreated treatment, which yielded the lowest mean of 4.00 Mg ha -1 . The results presented in tables (2,3,4) indicate that seed inoculation with Azotobacter and Azospirillum bacteria led to a significant increase in some vegetative growth traits (plant height, leaf area, chlorophyll content). This can be attributed to the role of biological fertilizers in improving vegetative growth and increasing the surface area of the root absorption zone, thereby enhancing water and nutrient uptake by the plants. ...
Article
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The experiment was conducted in the Al-Azawiya area, affiliated with the Musayyib project in Babil Governorate, during the winter agricultural season of 2023. The study aimed to investigate the effect of bio and organic fertilization and foliar spraying with boron on the growth and yield of yellow maize (variety: Al-Maha). The experiment was conducted using a factorial experiment based on a Randomized Complete Block Design (RCBD) and with three replications randomly distributed within three sectors, totaling 18 treatments to make the number of experimental units 54, The experiment included three factors: the first factor was bio-fertilization (seed inoculation) with a mixture of Azotobacter and Azospirillum at two levels (without inoculation, inoculation), The second factor was organic fertilization (sheep manure) added to the soil at three levels (0, 10, 20) Mg ha-1. The third factor was foliar spraying of boron as boric acid at three levels (0, 5, 10) mg L-1. The mean values of the treatments were compared using the Least Significant Difference (LSD) test at a significance level of 0.05. The results of the experiment showed that the addition of bio and organic fertilizers and foliar spraying with boron resulted in significant differences in all vegetative growth and yield Properties. Additionally, the results indicated significant interactions between the bio-fertilizer (seed inoculation) and organic fertilizer (20 Mg ha-1) and between the bio-fertilizer (seed inoculation) and foliar spraying with boron (10 mg L-1), as well as between the organic fertilizer (20 Mg ha-1) and foliar spraying with boron (10 mg L-1), resulting in significant differences in all growth and yield Properties. Similarly, significant interactions were observed between the bio-fertilizer (seed inoculation), organic fertilizer (20 Mg ha-1), and foliar spraying with boron (10 mg L-1), indicating significant differences in all growth and yield Properties.
... improve nutrient availability and stimulate plant growth [2]. Azospirillum spp bacteria are among the most important bacterial inoculants used in biofertilizer technology. ...
... Regarding the triple interaction between biofertilizer, organic fertilization, and boron, the treatment with biofertilizer + 20 Mg ha -1 + 10 mg L -1 significantly outperformed and yielded the highest mean of 10.15 Mg ha -1 compared to the untreated treatment, which yielded the lowest mean of 4.00 Mg ha -1 . The results presented in tables (2,3,4) indicate that seed inoculation with Azotobacter and Azospirillum bacteria led to a significant increase in some vegetative growth traits (plant height, leaf area, chlorophyll content). This can be attributed to the role of biological fertilizers in improving vegetative growth and increasing the surface area of the root absorption zone, thereby enhancing water and nutrient uptake by the plants. ...
... Nutrient deficiencies, particularly under drought conditions, can severely impact plant growth due to hindered nutrient absorption, translocation, and redistribution within the plant, especially in soils with low organic matter and moisture content (Marschner, 2011;Zipori et al., 2020). The application of organic matter, in conjunction with biofertilizers, by enhancing soil moisture retention, can optimize plant metabolic processes and increase nutrient use efficiency (Herrmann and Lesueur, 2013;Garcıá-Fraile et al., 2015;Raimi et al., 2017). Biofertilizers provide a wide spectrum of absorbable nutrients and growth promoters for plants, thus establishing a foundation for increased productivity per unit area (Bhattacharyya et al., 2020;Bizos et al., 2020;Jacob and Paranthaman, 2023;Melloni and Cardoso, 2023). ...
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Purpose This research evaluates the combined impact of chemical and biological fertilizers on ‘Zard’ olive trees, aiming to reduce chemical dependency, enhance fertilizer efficiency, and improve nutritional value, yield, and oil quality from 2020 to 2023. Method A factorial design within a randomized complete block was used, focusing on the first factor, soil chemical fertilizer application (CF) at three levels, 100% (CF100), 75% (CF75), and 50% (CF50) of the fertilizer requirement as determined by soil testing. This was coupled with foliar applications of 20-20-20 NPK fertilizer with micronutrients. The second factor, biological fertilizer application (BF), also comprised three levels: BF0 (control), soil-applied organic fertilizer without biological agents; BF1, which included a soil application of an organic fertilizer mix, mycorrhizal fungi, and the beneficial bacteria Bacillus subtilis and Pseudomonas fluorescens, supplemented with fulvic acid and amino acids; and BF1+BFF, where trees were treated with both soil and foliar applications of the aforementioned bacterial species, fulvic acid, and amino acids. Results The CF100+BF1+BFF treatment significantly increased fruit length (31.14%), diameter (41.61%), flesh thickness (30.48%), fresh weight (38.76%), dry weight (55.68%), and yield per tree (27.00%) compared to the control (CF100+BF0). Principal Component Analysis (PCA) identified CF100+BF1+BFF, CF75+BF1+BFF, and CF50+BF1+BFF as superior treatments for fruit characteristics, while CF50+BF1+BFF excelled in oil quality indicators. Conclusion The study recommends the CF75+BF1+BFF and CF50+BF1+BFF treatments for concurrent improvements in fruit and oil quality. The combined use of biological fertilizers with reduced chemical fertilizers is considered the superior and optimal approach for fertilizing ‘Zard’ cultivar olive orchards.
... The commercialization of biofertilizer began in 1895 when Nobbe and Hiltner marketed the endophytic rhizobia product under the "Nitragin" brand. Rhizobium was initially commercialized in India by N. V. Joshi, who was responsible for promoting plant growth in leguminous crops (García-Fraile et al. 2015). The Ministry of Agriculture launched the National Project on Development (NAD) of bioinoculants (NPDB) during the ninth Five-Year Plan. ...
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The world has changed exponentially from the time of famine to the existent, when food is produced globally to feed a population that is expanding at an exponential rate. The intensification of agriculture through the introduction of mechanical, industrial, and economic inputs has been a hallmark of major agricultural revolutions, which have enabled this transformation. However, the explosion of agricultural inputs consisting of fertilizers, pesticides, and irrigation brought about by this quick development in agriculture has also resulted in long-term environmental crises. These challenges have highlighted the pressing need to safeguard our communal spaces, especially the environment, by means of a participatory strategy that engages nations everywhere, irrespective of their level of development. One notable effort in this area is Zero Budget Natural Farming (ZBNF), which emphasizes the value of utilizing the complementary effects of plant and animal products to improve soil fertility, encourage the growth of beneficial microbes, and improve development of crops. The development of self-sustaining agro-ecosystems is the ultimate goal. Consequently, the world is depending on the use of microbial formulations in agriculture to address the "5F" crisis; food, feed, fuel, fertilizer, and finance. Despite the fact that there are now many studies being conducted in this area, the market need for effective microbial formulations outweigh the supply. Many different microbes have been considered so far for their potential as plant stimulants, but there are still innumerable soil microorganisms that need to be found in order to play a useful role in the formulation companies. The present review deals with improving the broad range of mechanism of microbial formulations, delivery methods, challenges and biosafety issue and assessment for agricultural sustainability that support the sustainable development goals (SDGs).
... In addition, some bacteria increase phosphorus solubility. Many studies have shown that the use of plant growth-supporting bacteria as biofertilizers helps increase plant production and soil fertility (Bhattacharyya and Jha, 2011;Garcia-Fraile et al., 2015;Vejan, 2016). ...
... These findings align with previous studies by Yaseen et al. (2018), who reported the promoting role of bacterial inoculation on micronutrients such as Mn, Fe, and Zn in wheat plants. Moreover, García-Fraile et al. (2015) highlighted the importance of biofertilizer application in enhancing plant growth by increasing nutrient availability in the rhizosphere through the production of antibiotics and the control of pathogenic bacteria. The integrated approach of bacterial inoculation holds promise for sustainable agricultural practices by optimizing nutrient dynamics in the soil. ...
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The geochemical analysis of Gafsa rock phosphate (GRP) revealed relatively high concentrations of essential plant minerals and trace heavy metals (HMs). Environmental contamination factors indicated moderate to very strong HM contamination due to GRP soil amendment. The potential use of the Serratia plymuthica BMA1 strain, which is known for its ability to solubilize GRP, to enhance mineral nutrition in Vicia faba L. and its role in HM rhizoaccumulation from GRP were explored. Pot experiments revealed that bacterization with S. plymuthica BMA1 in V. faba grown in sand supplemented with GRP as the sole source of phosphorus significantly increased the potassium concentration by 64% in roots and 40% in shoots, iron by 20% in roots and 10% in shoots, and manganese by 27% in roots and 20% in shoots compared to that in V. faba not inoculated with S. plymuthica BMA1. The total dry biomass of V. faba increased by approximately 85%, while the accumulation of cadmium (Cd), copper (Cu), zinc (Zn), and lead (Pb) in the roots increased by 114%, 30%, 37%, and 44%, respectively. However, in the shoots, they increased by 35%, 10%, 85%, and 25%, respectively, for Cd, Cu, Zn, and Pb compared to those in the non-inoculated V. faba. The evaluation of the HM translocation factor, bioaccumulation factor, and bioconcentration factor with GRP highlighted the key role of S. plymuthica BMA1 in preventing the mobility of toxic HMs from reaching the aerial parts of plants. These findings suggest that S. plymuthica BMA1 has the potential to enhance mineral nutrition in V. faba and facilitate the rhizoaccumulation of toxic HMs, which has implications for plant cultivation and human consumption.
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