Biofertilization of crops with plant growth promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. Biofertilizers are microbial preparations containing living cells of dif...Biofertilization of crops with plant growth promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. Biofertilizers are microbial preparations containing living cells of different microorganisms which have the ability to mobilize plant nutrients in soil from unusable to usable form. They are environmentally friendly, play a significant role in the crop production, help to build up the lost microflora and improve the soil health. Also, they increase crop yield by 20% - 30%, stimulate plant growth, are cost effective and provide optimal conditions for soil biological activity. They suppress pathogenic soil organisms, restore natural soil fertility and provide protection against drought and some soil borne diseases. Moreover, they degrade toxic organic chemicals, improve seed germination and aid in balancing soil pH in reducing soil erosion.展开更多
Oryza longistaminata is an African wild rice species with valuable agronomic traits and the donor parent of perennial rice.Endophytic bacteria play an important role in host health,adaptive evolution and stress tolera...Oryza longistaminata is an African wild rice species with valuable agronomic traits and the donor parent of perennial rice.Endophytic bacteria play an important role in host health,adaptive evolution and stress tolerance.However,endophytic bacterial communities in O.longistaminata and their plant growth-promoting(PGP)effects on the perennial rice of O.longistaminata offspring are poorly understood.In this study,the endophytic bacterial diversity,composition and network structures in the root,stem,and leaf tissues of O.longistaminata were characterized using Illumina sequencing of the 16S rRNA gene.The results suggested that O.longistaminata contains a multitude of niches for different endophytic bacteria,among which the root endosphere is more complex and functionally diverse than the stem and leaf endospheres.Tissue-specific biomarkers were identified,including Paludibaculum,Pseudactinotalea and Roseimarinus and others,for roots,Blautia for stems and Lachnospiraceae NK4A136 for leaves.The endophytic bacterial network of O.longistaminata was reassembled for various functions,including degradation/utilization/assimilation,detoxification,generation of precursor metabolites and energy,glycan pathways,macromolecule modification and metabolism.A total of 163 endophytic bacterial strains with PGP traits of potassium release,phosphate solubilization,nitrogen fixation,siderophore activity,indole-3-acetic acid(IAA)production,and 1-aminocyclopropane-1-carboxylate(ACC)deaminase activity were isolated from O.longistaminata.Eleven strains identified as Enterobacter cloacae,Enterobacter ludwigii,Stenotrophomonas maltophilia,Serratia fonticola,and Bacillus velezensis showed stable colonization abilities and PGP effects on perennial rice seedlings.Inoculated plants generally exhibited an enhanced root system and greater photosynthesis,biomass accumulation and nutrient uptake.Interestingly,two strains of E.cloacae have host genotype-dependent effects on perennial rice growth.The results of this study provide insights into the endophytic bacterial ecosystems of O.longistaminata,which can potentially be used as biofertilizers for sustainable perennial rice productivity.展开更多
Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers ha...Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers has become pervasive in agriculture.Nonetheless,the escalating prices of chemical fertilizers,coupled with new European regulations prohibiting the use of P fertilizers containing cadmium,have highlighted the urgency to identify environmentally friendly products and practices for P fertilization in agricultural soils.This comprehensive review delves into the current landscape of P fertilization from agricultural,political,and economic standpoints.We recognize the potential of microbes in mobilizing P,but emphasize the necessity for more robust research to establish their effectiveness in promoting plant P uptake under real-world conditions.Additionally,we explore the role of agricultural conservation practices,such as optimal tillage,diversified cropping systems,and increased organic carbon input,in conserving P.Furthermore,this review contemplates forthcoming innovations in research.These innovations encompass the development of enhanced formulations for biofertilizers and the undertaking of more comprehensive studies within the realm of conservation agriculture.All these endeavors collectively hold the potential to augment P accessibility to plants in a sustainable manner,thereby advancing agricultural sustainability and productivity.展开更多
Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multipl...Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multiple stages of development before yielding a final product. The final biofertilizer is used by legumes-protein-rich crops in symbiosis with rhizobia to enable biological nitrogen fixation increasing natural soil fertility. This study aims to determine the optimal formulation of a rhizobial biofertilizer to improve the performance of soybean (Glycine max L. cv. Docko). To this end, soybean seeds obtained from IRAD were coated with different formulations derived from locally sourced materials. Palm kernel oil was used as an adhesive in one group, while corn powder served as an adhesive in another. The coated seeds were then sown in the field. The results indicate that the combination of pigeon pea powder + sugarcane molasses, with palm kernel oil as an adhesive, produced the best nodulation (nitrogen fixation). This formulation also led to significant improvements in growth (+350%) and total nitrogen content (+1100%) compared to the bacterial broth inoculum control (B0) (P ≤ 0.01). These findings represent a significant advancement in improving nitrogen-fixing bacterial inoculants and enhancing soil fertility for the sustainable cultivation of soybeans in this tropical soil.展开更多
Global warming and climate change have made food production through conventional agriculture inefficient, and their effects on livestock and crop cultivation are leading to disruptions in the food supply. The troubles...Global warming and climate change have made food production through conventional agriculture inefficient, and their effects on livestock and crop cultivation are leading to disruptions in the food supply. The troubles are severe in regions suffering from improper land management and unsustainable practices. The Bio-CircularGreen(BCG) economic model, designed to reduce and recycle resources by using environmentally friendly procedures, has been developed. The Azolla plant represents an interesting model for BCG and for enhancing community networks in Southeast Asia(SEA) because it provides multipurpose materials. Azolla can be used for various applications in agriculture such as biofertilizer and animal feed. However, our understanding and utilization of Azolla are limited. Moreover, collaboration among farmers is insufficient to maximize the benefits of Azolla. In this study, we provide a comprehensive review of the role of Azolla in agriculture. We review the main properties of Azolla as biofertilizers, especially regarding rice production and the interaction with cyanobacteria. For livestock, we discuss procedures to use Azolla in animal feed and evaluate the ingredients of the meal. In addition, we discuss product qualities from livestock treated with Azolla in the diet. This review also describes Azolla-based farming, which is designed for efficient land use and promotes nutrient cycling.Hence, we show that the Azolla plant is one of the key factors for farm-based agroecosystem services which can drive sustainable bioresource management in SEA. Moreover, we also propose the potential development of Azolla to improve its properties as a biofertilizer, a functional feed for animals and humans, and a feedstock for bio-oil production.展开更多
The edible mushroom Agaricus bisporus L.plays a crucial ecological role in nutrient cycling and organic matter decomposition,alongside its increasing importance in the food and nutrition industry.This study explored e...The edible mushroom Agaricus bisporus L.plays a crucial ecological role in nutrient cycling and organic matter decomposition,alongside its increasing importance in the food and nutrition industry.This study explored ecological interventions to enhance the mushroom’s vitamin content by enriching its cultivation substrate with nanomaterials and biostimulatory agents.The experiment was conducted within the mushroom production project at Al-Qadisiyah Governorate,Iraq.The compost-based medium was amended with magnetic iron nanoparticles(N-FeO),carbon nanotube(CNT)suspensions,EM biofertilizer,and Atonik growth stimulant.Their ecological impact on the enrichment of fat-soluble(A,D,E)and water-soluble(B2,B3,B5,B6)vitamins in mushrooms was assessed.The study employed a Completely Randomized Design(CRD)with three replicates.Results revealed that the synergistic application of these eco-friendly treatments significantly enhanced the vitamin profiles of A.bisporus.The highest concentrations of vitamins B2 and B5(5.16 and 17.70 mg kg^(-1),respectively)and vitamin A(6.87 IU ml^(-1))were recorded under the combined quadruple treatment.Additionally,the triple treatment(N-FeO+EM+Atonik)notably increased levels of vitamins B2(4.47 mg kg^(-1)),B6(25.66 mg kg^(-1)),D(34.76 mg kg^(-1)),and vitamin A(6.87 IU ml^(-1)).Dual treatments(EM+Atonik)also significantly improved vitamin B2(4.54 mg kg^(-1))and vitamin E(3.30 mg kg^(-1))contents.These findings demonstrate that integrating nanomaterials and biostimulants can serve as an ecological strategy to improve the nutritional quality of mushrooms while promoting sustainable agricultural practices.展开更多
This study was carried out with the aim of investigating the effect of indigenous microorganism (IMO), effective (EM) and mineral fertilizers (NPK) on the yield and nutritional value of groundnut (Arachis hypogaea) in...This study was carried out with the aim of investigating the effect of indigenous microorganism (IMO), effective (EM) and mineral fertilizers (NPK) on the yield and nutritional value of groundnut (Arachis hypogaea) in Western Cameroon (Baboutcha-Fongam). The study was conducted during two consecutive years, using a completely randomized block design of 8 treatments repeated three times in each subblock. The sub-plots were enriched with 0, 10, 20 and 40 g corresponding to the treatment of EM and IMO respectively and 3.2 g of NPK in 2019. Subsequently, the best dose that resulted in excellent yields was repeated for the rest of the experiment in 2020. The yield parameters and nutritional value of the two varieties of Arachis hypogaea used in the two consecutive years increase with the contribution of the different doses compared to the control. Overall, a significant increase (p A. hypogaea plants fertilized with EM 20 g (2.15 ± 0.24 and 2.01 ± 0.23 t/ha) and plants fertilized with NPK 3.2 g (2.36 ± 0.65 and 2.04 ± 0.17 t/ha) was not significant. On the other hand, there was a significant difference (P ≤ 0.05) between plants fertilized with IMO 10 g (2.65 ± 0.17 and 2.24 ± 0.2 t/ha) and plants fertilized with EM 20 g and plants fertilized with NPK 3.2 g for both varieties during the two years combined. In addition to being local and therefore adapted to environmental conditions, IMOs could be a promising biological means for improving soil fertility in Cameroon.展开更多
The objective of the study was to evaluate the effects of nine plant growth-promoting rhizobacteria (PGPR) alone or in combination on maize seed germination and seedling growth under laboratory and greenhouse conditio...The objective of the study was to evaluate the effects of nine plant growth-promoting rhizobacteria (PGPR) alone or in combination on maize seed germination and seedling growth under laboratory and greenhouse conditions. The germination and growth tests were carried out in square petri dishes and pots. Maize seeds were inoculated with suspension of 108 CFU/ml of rhizobacteria. The experimental device was a random block of 16 treatments with four repetitions. Germination test results showed that seeds inoculated with PGPR including the control induced good germination in the range of 93.75% to 100%. The vigor index and root length of the seeds treated with Bacillus panthothenicus were significantly improved by 76.64% and 58.86%, respectively, while the maximal lengths of the seedlings were obtained with Pseudomonas cichorii with an increase of 118.95%. In greenhouse experience, data demonstrated that Serratia marcescens better improved the leaf area, height and underground biomass, respectively by 58.83%, 108.43%, and 59.16% as compared to the control. The highest fresh aerial biomass and air dry matter was obtained with plants treated only with Pseudomonas putida. These results show the potential to use such rhizobacteria as biofertilizers to improve maize productivity in Benin.展开更多
Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments （e.g., cattle dung, vermicompost, biofertilizer） a...Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments （e.g., cattle dung, vermicompost, biofertilizer） and earthworm inoculations （Eisenia fetida） on saline soils and cotton growth were investigated during i year of cotton cultivation. Compared to the control （applied with inorganic NPK fertilizer）, applying organic amendments improved soil physicochemical properties. Biofertilizer application improved available nutrient content, reduced short-term soil electrical conductivity, and produced the highest cotton yield, whereas cattle dung and vermicompost applications resulted in higher soil organic matter content. Application of organic amendments significantly increased soil microbial biomass carbon during the flowering period, which sharply declined at harvest. This was especially true for the biofertilizer treatment, which also exhibited lower nematode abundance compared with the other organic materials. Earthworm inoculation following cattle dung application failed to significantly change soil physicochemical properties when compared to the treatments without earthworm inoculation. Results suggest that biofertilizer application to saline soil would improve soil nutrient status in the short-term, whereas cattle dung application would improve soil organic matter content and increase soil organism abundance to a greater extent. However, different strategies might be required for long-term saline soil remediation.展开更多
Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia...Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia sp. based on 16S rDNA sequence analysis, as wel as phenotypic and biochemical characterizations. This bacterium presented nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity and phosphate solubilizing ability;inhibited the growth of Sclerotinia sclerotiorum, Gibberel a zeae and Verticil ium dahliae;and produced smal quantities of indole acetic acid (IAA). In green house experiments, signiifcant increases in shoot height and weight, root length and weight, and stem diameter were observed on tomato plants in 30 d after inoculation with strain 7016. Result of 16S rDNA PCR-DGGE showed that 7016 survived in the rhizosphere of tomato seedlings. In the ifeld experiments, Burkholderia sp. 7016 enhanced the tomato yield and signiifcantly promoted activities of soil urease, phosphatase, sucrase, and catalase. Al these results demonstrated Burkholderia sp. 7016 as a valuable PGPR and a candidate of biofertilizer.展开更多
The advent of civilization has made humans dependent on plants for food and medicine,leading to the intensification of agricultural production.The intense cultivation of crops has resulted in the depletion of availabl...The advent of civilization has made humans dependent on plants for food and medicine,leading to the intensification of agricultural production.The intense cultivation of crops has resulted in the depletion of available nutrients from soil,thereby demanding the application of excess nutrients to soil to improve yield.Thus,mineral fertilizer discovery and application have,in many ways,contributed greatly to meeting global food demands.However,aside from the positive effects of mineral fertilizers,their excessive application to soil produces large amounts of pollutants that affect environmental sustainability.This necessitates the study of the major mineral fertilizer elements(nitrogen(N),phosphorus(P),and potassium(K)),the forms in which they are applied to soil,and their chemistry/reactions in soil.Here,we reviewed the forms of different N,P,and K mineral fertilizers to provide current knowledge on their constituents,the chemistry of N,P,and K in soil to understand the reactions they undertake in soil,the efficient methods of fertilizer application for environmental sustainability,the effects of mineral fertilizer loss to the environment,and improved fertilization technologies for environmental sustainability.Nanofertilizers are a promising technology for sustainable agricultural production and are discussed in detail in this review.展开更多
In this study, Aspergillus niger 1107 was isolated and identified as an efficient phosphate-solubilizing fungus （PSF）. This strain generated 689 mg soluble P L-1 NBRIP medium after 10 d of culture. To produce an aff...In this study, Aspergillus niger 1107 was isolated and identified as an efficient phosphate-solubilizing fungus （PSF）. This strain generated 689 mg soluble P L-1 NBRIP medium after 10 d of culture. To produce an affordable biofertilizer using A. niger 1107, the potential of widely available carrier materials for growth and maintenance of this strain were evaluated. The effects of sterilization procedures （autoclaving and gamma-ray irradiation） on the suitability of these carriers to maintain growth of the fungus were also investigated. The carrier materials were peat, corn cobs with 20% （w/w） perlite （CCP）, wheat husks with 20% （w/w） perlite （WHP）, and composted cattle manure with 20% （w/w） perlite （CCMP）. In the first 5-6 mon of storage, the carriers sterilized by gamma-ray irradiation maintained higher inoculum loads than those in carriers sterilized by autoclaving. However, this effect was not detectable after 7 mon of storage. For the P-biofertilizer on WHP, more than 2.0× 10^7 viable spores of A. niger g-1 inoculant survived after 7 mon of storage. When this biofertilizer was applied to Chinese cabbage in a pot experiment, there were 5.6×10^6 spores of A. niger g-1 soil before plant harvesting. In the pot experiment, Chinese cabbage plants grown in soil treated with peat- and WHP-based P-biofertilizers showed significantly greater growth （P〈0.05） than that of plants grown in soil treated with free-cell biofertilizer or the CCMP-based biofertilizer. Also, the peat- and WHP-based P-biofertilizers increased the available P content in soil.展开更多
A field experiment was carried out to evaluate the feasibility of inoculating rice seedlings with biofertilizers(Azospirillum and Trichoderma) in order to reduce the use of chemical inorganic nitrogen(N)fertilizer on ...A field experiment was carried out to evaluate the feasibility of inoculating rice seedlings with biofertilizers(Azospirillum and Trichoderma) in order to reduce the use of chemical inorganic nitrogen(N)fertilizer on rice variety BU Dhan 1. The plant performances were better when 25% less inorganic N was applied with Trichoderma and combined application of Trichoderma and Azospirillum. Plants contained the highest chlorophyll concentrations when they were treated with 75% N + Trichoderma. Considering the yield attributes, 75% N + Trichoderma and 75% N + Trichoderma + Azospirillum performed similar to the control. The grain yield of rice was similar to the recommended dose even with 25% less N application. Application of Trichoderma resulted higher yield, followed by combined application with Azospirillum. Results revealed the greater scope of applying biofertilizer(Trichoderma) to supplement chemical N fertilizer with optimum yield of rice.展开更多
Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have l...Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries.This results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus fertilizers.To compensate for these losses,massive use of K fertilizers in agriculture has been suggested.Potassium fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic fertilizers.Potassium-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable option.The possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by researchers.In this review,the existing forms of K in soils and their availability and dynamic equilibrium are discussed.In addition,different K fertilizers and their advantages and disadvantages for crops are described.Furthermore,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are reviewed.Screening and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and fungi.This review may serve as a proposal for the future research avenues identified here.展开更多
Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alte...Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios.展开更多
A field study was conducted at the Agricultural Research Farm of Razi University, Kermanshah, Iran to investigate the effects of phosphate biofertilizer, row spacing and plant density on corn yield and weed growth. Th...A field study was conducted at the Agricultural Research Farm of Razi University, Kermanshah, Iran to investigate the effects of phosphate biofertilizer, row spacing and plant density on corn yield and weed growth. The experiment was a factorial with three factors arranged in a randomized complete block design with three replications. The first factor was phosphate biofertilizer (inoculation and non-inoculation), the second was row spacing (conventional (75 cm) and reduced (50 cm)) and the third was plant density (66,666 plants·ha–1 (conventional plant density) 83,333 and 99,999 plants·ha–1 (1.25 and 1.5 times the conventional plant density, respectively)). Results indicated that corn yield and weed growth were significantly influenced by row spacing and plant density. So that, corn yield improved and weed biomass diminished in response to increasing plant density and decreasing row spacing. However, phosphate biofertilizer had no significant effect on corn yield, whereas, weed biomass was notably increased when phosphate biofertilizer was applied. Overall, this study revealed that both yield and weed control in corn field can be improved by alteration of the planting arrangement.展开更多
In this study,10 bacterial strains were isolated from the rhizosphere of coniferous trees on Mount Tla′loc in Mexico.The strains were characterized by their capacity to produce auxins,solubilize phosphates and stimul...In this study,10 bacterial strains were isolated from the rhizosphere of coniferous trees on Mount Tla′loc in Mexico.The strains were characterized by their capacity to produce auxins,solubilize phosphates and stimulate mycelial growth of the ectomycorrhizal fungus Suillus sp.All isolates were identified at the molecular level.Moreover,an experiment was established to evaluate the response of Pinus pseudostrobus seedlings to inoculation with the rhizobacteria strains.The isolated strains belonged to the species Cupriavidus basilensis,Rhodococcus qingshengii,R.erythropolis,Pseudomonas spp.,P.gessardii,Stenotrophomonas rhizophila and Cohnella sp.All of the strains produced auxins;the best producer was R.erythropolis CPT9(76.4 lg mL^-1).P.gessardii CPT6 solubilized phosphate at a significant level(443 lg mL^-1).The strain S.rhizophila CPT8 significantly increased the radial growth of the ectomycorrhizal fungus Suillus sp.by 18.8%.Five strains increased the dry mass of the shoots;R.qingshengii CPT4 and R.erythropolis CPT9 increased growth the most,by more than 20%.Inoculation with plant-growth-promoting rhizobacteria can be a very useful practice in a forest nursery to produce healthy,vigorous plants.展开更多
Silicon(Si)is the second most abundant element in the Earth’s crust and has numerous roles in both soils and plants,although it is inaccessible to plants in its native state(insoluble silicate minerals).This inaccess...Silicon(Si)is the second most abundant element in the Earth’s crust and has numerous roles in both soils and plants,although it is inaccessible to plants in its native state(insoluble silicate minerals).This inaccessibility can lead to insufficiency,which induces anomalies in plant growth and development.Specifically,Si alleviates various biotic and abiotic stresses in plants by enhancing tolerance mechanisms at different stages of uptake/deposition as a monosilicic acid.Exclusive utilization of conventional Si fertilizers to boost agricultural productivity in an attempt to meet the world’s ever-increasing food demand may result in surface and groundwater pollution,waterway eutrophication,soil fertility depletion,and accumulation of hazardous elements such as arsenic in soil.By addressing the drawbacks of chemical fertilizers,this review emphasizes an environmentally friendly alternative,namely,Si-solubilizing microorganisms(SSMs),as bioinoculants to liberate soluble Si and thus making it available to plants.A deep understanding of recent advances in the functional diversity,colonization patterns,modes of action,role in biogeochemical cycling,and plant stress tolerance of SSMs and their implementation in Si-based agrowaste management through the fabrication of nanoparticles,could help to establish a reliable tool for economically and environmentally sustainable agriculture.From this perspective,in this review,we comprehensively summarize the latest methodologies for the isolation,screening,and characterization of SSMs and Si solubilization mechanisms,including ligands(divalent cations),acids(inorganic and organic),alkali(nucleophilic attack),extracellular polysaccharides,and factors affecting them,as well as Si-mediated regulation of gene expression involved in Si uptake,transportation,and mineralization.We have critically revised the role of SSMs according to the current literature.The contributions of SSMs to biofertilization are still being explored;hence,we also discuss trajectories for future research in relation to SSM-mediated increases in bioavailable Si.This will create new strategies to reduce the use of agrochemicals,improve plant health,and help us to globally gravitate towards more sustainable agricultural practices,based on the concept of a circular economy.展开更多
Ammonia（NH3） volatilization is one of the primary pathways of nitrogen（N） loss from soils after chemical fertilizer is applied, especially from the alkaline soils in Northern China, which results in lower efficien...Ammonia（NH3） volatilization is one of the primary pathways of nitrogen（N） loss from soils after chemical fertilizer is applied, especially from the alkaline soils in Northern China, which results in lower efficiency for chemical fertilizers. Therefore, we conducted an incubation experiment using an alkaline soil from Tianjin（p H 8.37–8.43） to evaluate the suppression effect of Trichoderma viride（T. viride） biofertilizer on NH3 volatilization, and compared the differences in microbial community structure among all samples. The results showed that viable T. viride biofertilizer（T） decreased NH3 volatilization by 42.21% compared with conventional fertilizer（（CK）, urea）, while nonviable T. viride biofertilizer（TS） decreased NH3 volatilization by 32.42%. NH3 volatilization was significantly higher in CK and sweet potato starch wastewater（SPSW） treatments during the peak period. T. viride biofertilizer also improved the transfer of ammonium from soil to sweet sorghum. Plant dry weights increased 91.23% and 61.08% for T and TS, respectively, compared to CK. Moreover, T. viride biofertilizer enhanced nitrification by increasing the abundance of ammonium-oxidizing archaea（AOA） and ammonium-oxidizing bacteria（AOB）. The results of high-throughput sequencing indicated that the microbial community structure and composition were significantly changed by the application of T. viride biofertilizer. This study demonstrated the immense potential of T. viride biofertilizer in reducing NH3 volatilization from alkaline soil and simultaneously improving the utilization of fertilizer N by sweet sorghum.展开更多
Myo-inositol phosphates (phytates) are important biological molecules produced largely by plants to store phosphorus. Phytate is very abundant in many different soils making up a large portion of all soil phosphorus. ...Myo-inositol phosphates (phytates) are important biological molecules produced largely by plants to store phosphorus. Phytate is very abundant in many different soils making up a large portion of all soil phosphorus. This review assesses current phytase science from the perspective of its substrate, phytate, by examining the intricate relationship between the phytate-hydrolyzing enzymes and phytate as their substrate. Specifically, we examine available data on phytate’s structural features, distribution in nature and functional roles. The role of phytases and their localization in soil and plant tissues are evaluated. We provide a summary of the current biotechnological advances in using industrial or recombinant phytases to improve plant growth and animal nutrition. The prospects of future discovery of novel phytases with improved biochemical properties and bioengineering of existing enzymes are also discussed. Two alternative but complementary directions to increase phosphorus bioavailability through the more efficient utilization of soil phytate are currently being developed. These approaches take advantage of microbial phytases secreted into rhizosphere either by phytase-producing microbes (biofertilizers) or by genetically engineered plants. More research on phytate metabolism in soils and plants is needed to promote environmentally friendly, more productive and sustainable agriculture.展开更多
基金supported by the grant from the EU Regional Development Fund through the Polish Innovation Economy Operational Program,contract No.UDA-POIG.01.03.01-10-109/08.
文摘Biofertilization of crops with plant growth promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. Biofertilizers are microbial preparations containing living cells of different microorganisms which have the ability to mobilize plant nutrients in soil from unusable to usable form. They are environmentally friendly, play a significant role in the crop production, help to build up the lost microflora and improve the soil health. Also, they increase crop yield by 20% - 30%, stimulate plant growth, are cost effective and provide optimal conditions for soil biological activity. They suppress pathogenic soil organisms, restore natural soil fertility and provide protection against drought and some soil borne diseases. Moreover, they degrade toxic organic chemicals, improve seed germination and aid in balancing soil pH in reducing soil erosion.
基金supported by funding from the National Natural Science Foundation of China(32060593 and 32060474)the Yunnan Provincial Science and Technology Department+4 种基金China(202101AT070021 and 202101AS070001)the Yunnan Provincial Department of Education Science Research Fund ProjectChina(2023J0006)the Graduate Innovation Project of Yunnan UniversityChina(KC-22223012 and ZC-22222760)。
文摘Oryza longistaminata is an African wild rice species with valuable agronomic traits and the donor parent of perennial rice.Endophytic bacteria play an important role in host health,adaptive evolution and stress tolerance.However,endophytic bacterial communities in O.longistaminata and their plant growth-promoting(PGP)effects on the perennial rice of O.longistaminata offspring are poorly understood.In this study,the endophytic bacterial diversity,composition and network structures in the root,stem,and leaf tissues of O.longistaminata were characterized using Illumina sequencing of the 16S rRNA gene.The results suggested that O.longistaminata contains a multitude of niches for different endophytic bacteria,among which the root endosphere is more complex and functionally diverse than the stem and leaf endospheres.Tissue-specific biomarkers were identified,including Paludibaculum,Pseudactinotalea and Roseimarinus and others,for roots,Blautia for stems and Lachnospiraceae NK4A136 for leaves.The endophytic bacterial network of O.longistaminata was reassembled for various functions,including degradation/utilization/assimilation,detoxification,generation of precursor metabolites and energy,glycan pathways,macromolecule modification and metabolism.A total of 163 endophytic bacterial strains with PGP traits of potassium release,phosphate solubilization,nitrogen fixation,siderophore activity,indole-3-acetic acid(IAA)production,and 1-aminocyclopropane-1-carboxylate(ACC)deaminase activity were isolated from O.longistaminata.Eleven strains identified as Enterobacter cloacae,Enterobacter ludwigii,Stenotrophomonas maltophilia,Serratia fonticola,and Bacillus velezensis showed stable colonization abilities and PGP effects on perennial rice seedlings.Inoculated plants generally exhibited an enhanced root system and greater photosynthesis,biomass accumulation and nutrient uptake.Interestingly,two strains of E.cloacae have host genotype-dependent effects on perennial rice growth.The results of this study provide insights into the endophytic bacterial ecosystems of O.longistaminata,which can potentially be used as biofertilizers for sustainable perennial rice productivity.
基金financed by the Spanish Ministry of Science and Innovation and the European Regional Development Fund(ERDF)(No.PID20211234690BI00)the European Joint Program EJP_Soil(TRACE-Soils)(No.862695)+1 种基金the Spanish Ministry of Science and Innovation(RED2018-102624TMCIN/AEI/10.13039/501100011033)the Project PREPSOIL European Union(No.101070045,HORIZON CSA)。
文摘Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers has become pervasive in agriculture.Nonetheless,the escalating prices of chemical fertilizers,coupled with new European regulations prohibiting the use of P fertilizers containing cadmium,have highlighted the urgency to identify environmentally friendly products and practices for P fertilization in agricultural soils.This comprehensive review delves into the current landscape of P fertilization from agricultural,political,and economic standpoints.We recognize the potential of microbes in mobilizing P,but emphasize the necessity for more robust research to establish their effectiveness in promoting plant P uptake under real-world conditions.Additionally,we explore the role of agricultural conservation practices,such as optimal tillage,diversified cropping systems,and increased organic carbon input,in conserving P.Furthermore,this review contemplates forthcoming innovations in research.These innovations encompass the development of enhanced formulations for biofertilizers and the undertaking of more comprehensive studies within the realm of conservation agriculture.All these endeavors collectively hold the potential to augment P accessibility to plants in a sustainable manner,thereby advancing agricultural sustainability and productivity.
文摘Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multiple stages of development before yielding a final product. The final biofertilizer is used by legumes-protein-rich crops in symbiosis with rhizobia to enable biological nitrogen fixation increasing natural soil fertility. This study aims to determine the optimal formulation of a rhizobial biofertilizer to improve the performance of soybean (Glycine max L. cv. Docko). To this end, soybean seeds obtained from IRAD were coated with different formulations derived from locally sourced materials. Palm kernel oil was used as an adhesive in one group, while corn powder served as an adhesive in another. The coated seeds were then sown in the field. The results indicate that the combination of pigeon pea powder + sugarcane molasses, with palm kernel oil as an adhesive, produced the best nodulation (nitrogen fixation). This formulation also led to significant improvements in growth (+350%) and total nitrogen content (+1100%) compared to the bacterial broth inoculum control (B0) (P ≤ 0.01). These findings represent a significant advancement in improving nitrogen-fixing bacterial inoculants and enhancing soil fertility for the sustainable cultivation of soybeans in this tropical soil.
基金Mahidol University for the support of a “Scholarship for PhD Student”, Thailandthe the cooperation with the National Science and Technology Development Agency and Mahidol University of “the Scholarship for the Development of High Quality Research Graduates in Science and Technology Project”, Thailand。
文摘Global warming and climate change have made food production through conventional agriculture inefficient, and their effects on livestock and crop cultivation are leading to disruptions in the food supply. The troubles are severe in regions suffering from improper land management and unsustainable practices. The Bio-CircularGreen(BCG) economic model, designed to reduce and recycle resources by using environmentally friendly procedures, has been developed. The Azolla plant represents an interesting model for BCG and for enhancing community networks in Southeast Asia(SEA) because it provides multipurpose materials. Azolla can be used for various applications in agriculture such as biofertilizer and animal feed. However, our understanding and utilization of Azolla are limited. Moreover, collaboration among farmers is insufficient to maximize the benefits of Azolla. In this study, we provide a comprehensive review of the role of Azolla in agriculture. We review the main properties of Azolla as biofertilizers, especially regarding rice production and the interaction with cyanobacteria. For livestock, we discuss procedures to use Azolla in animal feed and evaluate the ingredients of the meal. In addition, we discuss product qualities from livestock treated with Azolla in the diet. This review also describes Azolla-based farming, which is designed for efficient land use and promotes nutrient cycling.Hence, we show that the Azolla plant is one of the key factors for farm-based agroecosystem services which can drive sustainable bioresource management in SEA. Moreover, we also propose the potential development of Azolla to improve its properties as a biofertilizer, a functional feed for animals and humans, and a feedstock for bio-oil production.
文摘The edible mushroom Agaricus bisporus L.plays a crucial ecological role in nutrient cycling and organic matter decomposition,alongside its increasing importance in the food and nutrition industry.This study explored ecological interventions to enhance the mushroom’s vitamin content by enriching its cultivation substrate with nanomaterials and biostimulatory agents.The experiment was conducted within the mushroom production project at Al-Qadisiyah Governorate,Iraq.The compost-based medium was amended with magnetic iron nanoparticles(N-FeO),carbon nanotube(CNT)suspensions,EM biofertilizer,and Atonik growth stimulant.Their ecological impact on the enrichment of fat-soluble(A,D,E)and water-soluble(B2,B3,B5,B6)vitamins in mushrooms was assessed.The study employed a Completely Randomized Design(CRD)with three replicates.Results revealed that the synergistic application of these eco-friendly treatments significantly enhanced the vitamin profiles of A.bisporus.The highest concentrations of vitamins B2 and B5(5.16 and 17.70 mg kg^(-1),respectively)and vitamin A(6.87 IU ml^(-1))were recorded under the combined quadruple treatment.Additionally,the triple treatment(N-FeO+EM+Atonik)notably increased levels of vitamins B2(4.47 mg kg^(-1)),B6(25.66 mg kg^(-1)),D(34.76 mg kg^(-1)),and vitamin A(6.87 IU ml^(-1)).Dual treatments(EM+Atonik)also significantly improved vitamin B2(4.54 mg kg^(-1))and vitamin E(3.30 mg kg^(-1))contents.These findings demonstrate that integrating nanomaterials and biostimulants can serve as an ecological strategy to improve the nutritional quality of mushrooms while promoting sustainable agricultural practices.
文摘This study was carried out with the aim of investigating the effect of indigenous microorganism (IMO), effective (EM) and mineral fertilizers (NPK) on the yield and nutritional value of groundnut (Arachis hypogaea) in Western Cameroon (Baboutcha-Fongam). The study was conducted during two consecutive years, using a completely randomized block design of 8 treatments repeated three times in each subblock. The sub-plots were enriched with 0, 10, 20 and 40 g corresponding to the treatment of EM and IMO respectively and 3.2 g of NPK in 2019. Subsequently, the best dose that resulted in excellent yields was repeated for the rest of the experiment in 2020. The yield parameters and nutritional value of the two varieties of Arachis hypogaea used in the two consecutive years increase with the contribution of the different doses compared to the control. Overall, a significant increase (p A. hypogaea plants fertilized with EM 20 g (2.15 ± 0.24 and 2.01 ± 0.23 t/ha) and plants fertilized with NPK 3.2 g (2.36 ± 0.65 and 2.04 ± 0.17 t/ha) was not significant. On the other hand, there was a significant difference (P ≤ 0.05) between plants fertilized with IMO 10 g (2.65 ± 0.17 and 2.24 ± 0.2 t/ha) and plants fertilized with EM 20 g and plants fertilized with NPK 3.2 g for both varieties during the two years combined. In addition to being local and therefore adapted to environmental conditions, IMOs could be a promising biological means for improving soil fertility in Cameroon.
基金the“Centre National de Specialisation sur le Mais(CNS-Mais),the National Fund for scientific research and Innovation Technology(FNRSIT)for theit financial supports.
文摘The objective of the study was to evaluate the effects of nine plant growth-promoting rhizobacteria (PGPR) alone or in combination on maize seed germination and seedling growth under laboratory and greenhouse conditions. The germination and growth tests were carried out in square petri dishes and pots. Maize seeds were inoculated with suspension of 108 CFU/ml of rhizobacteria. The experimental device was a random block of 16 treatments with four repetitions. Germination test results showed that seeds inoculated with PGPR including the control induced good germination in the range of 93.75% to 100%. The vigor index and root length of the seeds treated with Bacillus panthothenicus were significantly improved by 76.64% and 58.86%, respectively, while the maximal lengths of the seedlings were obtained with Pseudomonas cichorii with an increase of 118.95%. In greenhouse experience, data demonstrated that Serratia marcescens better improved the leaf area, height and underground biomass, respectively by 58.83%, 108.43%, and 59.16% as compared to the control. The highest fresh aerial biomass and air dry matter was obtained with plants treated only with Pseudomonas putida. These results show the potential to use such rhizobacteria as biofertilizers to improve maize productivity in Benin.
基金supported by the National Natural Science Foundation of China (No. 41371305)the National Key Research and Development Program of China (No. 2017YFD0202000)
文摘Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments （e.g., cattle dung, vermicompost, biofertilizer） and earthworm inoculations （Eisenia fetida） on saline soils and cotton growth were investigated during i year of cotton cultivation. Compared to the control （applied with inorganic NPK fertilizer）, applying organic amendments improved soil physicochemical properties. Biofertilizer application improved available nutrient content, reduced short-term soil electrical conductivity, and produced the highest cotton yield, whereas cattle dung and vermicompost applications resulted in higher soil organic matter content. Application of organic amendments significantly increased soil microbial biomass carbon during the flowering period, which sharply declined at harvest. This was especially true for the biofertilizer treatment, which also exhibited lower nematode abundance compared with the other organic materials. Earthworm inoculation following cattle dung application failed to significantly change soil physicochemical properties when compared to the treatments without earthworm inoculation. Results suggest that biofertilizer application to saline soil would improve soil nutrient status in the short-term, whereas cattle dung application would improve soil organic matter content and increase soil organism abundance to a greater extent. However, different strategies might be required for long-term saline soil remediation.
基金supported by the National Natural Science Foundation of China (31100364)the National Nonprofit Institute Research Grant of Chinese Academy of Agricultural Sciences (CAAS, IARRP-2014-20)
文摘Aiming at searching for plant growth promoting rhizobacteria (PGPR), a bacterium strain coded as 7016 was isolated from soybean rhizosphere and was characterized in the present study. It was identiifed as Burkholderia sp. based on 16S rDNA sequence analysis, as wel as phenotypic and biochemical characterizations. This bacterium presented nitrogenase activity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity and phosphate solubilizing ability;inhibited the growth of Sclerotinia sclerotiorum, Gibberel a zeae and Verticil ium dahliae;and produced smal quantities of indole acetic acid (IAA). In green house experiments, signiifcant increases in shoot height and weight, root length and weight, and stem diameter were observed on tomato plants in 30 d after inoculation with strain 7016. Result of 16S rDNA PCR-DGGE showed that 7016 survived in the rhizosphere of tomato seedlings. In the ifeld experiments, Burkholderia sp. 7016 enhanced the tomato yield and signiifcantly promoted activities of soil urease, phosphatase, sucrase, and catalase. Al these results demonstrated Burkholderia sp. 7016 as a valuable PGPR and a candidate of biofertilizer.
文摘The advent of civilization has made humans dependent on plants for food and medicine,leading to the intensification of agricultural production.The intense cultivation of crops has resulted in the depletion of available nutrients from soil,thereby demanding the application of excess nutrients to soil to improve yield.Thus,mineral fertilizer discovery and application have,in many ways,contributed greatly to meeting global food demands.However,aside from the positive effects of mineral fertilizers,their excessive application to soil produces large amounts of pollutants that affect environmental sustainability.This necessitates the study of the major mineral fertilizer elements(nitrogen(N),phosphorus(P),and potassium(K)),the forms in which they are applied to soil,and their chemistry/reactions in soil.Here,we reviewed the forms of different N,P,and K mineral fertilizers to provide current knowledge on their constituents,the chemistry of N,P,and K in soil to understand the reactions they undertake in soil,the efficient methods of fertilizer application for environmental sustainability,the effects of mineral fertilizer loss to the environment,and improved fertilization technologies for environmental sustainability.Nanofertilizers are a promising technology for sustainable agricultural production and are discussed in detail in this review.
基金financially supported by the Special Fund for Agro-Scientific Research in the Public Interest, China (201003014)the Central Public-Interest ScientificInstitution Basal Research Fund, China (202-27)
文摘In this study, Aspergillus niger 1107 was isolated and identified as an efficient phosphate-solubilizing fungus （PSF）. This strain generated 689 mg soluble P L-1 NBRIP medium after 10 d of culture. To produce an affordable biofertilizer using A. niger 1107, the potential of widely available carrier materials for growth and maintenance of this strain were evaluated. The effects of sterilization procedures （autoclaving and gamma-ray irradiation） on the suitability of these carriers to maintain growth of the fungus were also investigated. The carrier materials were peat, corn cobs with 20% （w/w） perlite （CCP）, wheat husks with 20% （w/w） perlite （WHP）, and composted cattle manure with 20% （w/w） perlite （CCMP）. In the first 5-6 mon of storage, the carriers sterilized by gamma-ray irradiation maintained higher inoculum loads than those in carriers sterilized by autoclaving. However, this effect was not detectable after 7 mon of storage. For the P-biofertilizer on WHP, more than 2.0× 10^7 viable spores of A. niger g-1 inoculant survived after 7 mon of storage. When this biofertilizer was applied to Chinese cabbage in a pot experiment, there were 5.6×10^6 spores of A. niger g-1 soil before plant harvesting. In the pot experiment, Chinese cabbage plants grown in soil treated with peat- and WHP-based P-biofertilizers showed significantly greater growth （P〈0.05） than that of plants grown in soil treated with free-cell biofertilizer or the CCMP-based biofertilizer. Also, the peat- and WHP-based P-biofertilizers increased the available P content in soil.
基金Financial support was delivered by Research Management Cell of Bangabandhu Sheikh Mujibur Rahman Agricultural University(BSMRAU)
文摘A field experiment was carried out to evaluate the feasibility of inoculating rice seedlings with biofertilizers(Azospirillum and Trichoderma) in order to reduce the use of chemical inorganic nitrogen(N)fertilizer on rice variety BU Dhan 1. The plant performances were better when 25% less inorganic N was applied with Trichoderma and combined application of Trichoderma and Azospirillum. Plants contained the highest chlorophyll concentrations when they were treated with 75% N + Trichoderma. Considering the yield attributes, 75% N + Trichoderma and 75% N + Trichoderma + Azospirillum performed similar to the control. The grain yield of rice was similar to the recommended dose even with 25% less N application. Application of Trichoderma resulted higher yield, followed by combined application with Azospirillum. Results revealed the greater scope of applying biofertilizer(Trichoderma) to supplement chemical N fertilizer with optimum yield of rice.
文摘Until recently,potassium(K)has not received considerable attention because of the general belief that soils contain ample amounts of this element.In addition,low rates of K fertilizer application in agriculture have led to rapid depletion of K in the rhizosphere soil in many underdeveloped countries.This results in various negative impacts,including preventing optimum utilization of applied nitrogen and phosphorus fertilizers.To compensate for these losses,massive use of K fertilizers in agriculture has been suggested.Potassium fertilizers are manufactured from rock minerals,particularly sylvite(KCl)and carnallite(KCl·MgCl2·6H2O).Unfortunately,to date,there is no cost-effective technology available for converting rock minerals into potassic fertilizers.Potassium-solubilizing microorganisms(KSMs)can release K from soil/minerals into plant-available forms,which could be a sustainable option.The possibility of using KSMs as efficient biofertilizers to improve crop production has been increasingly highlighted by researchers.In this review,the existing forms of K in soils and their availability and dynamic equilibrium are discussed.In addition,different K fertilizers and their advantages and disadvantages for crops are described.Furthermore,the microorganisms usually reported as K solubilizers,the research progress on KSMs,and future insights on the use of these KSMs in agriculture are reviewed.Screening and analyses of the published literature show that organic acid production is the common mechanism of K solubilization by bacteria and fungi.This review may serve as a proposal for the future research avenues identified here.
基金financially supported by Project PTDC/BIA-MIC/29736/2017funded by the European Regional Development Fund(FEDER)through COMPETE2020-Programa Operacional Competitividade e Internacionalizacao(POCI)and the Portuguese Foundation for Science and Technology(FCT/MCTES)by the Centre for Environmental and Marine Studies(CESAM,Portugal)(UID/AMB/50017-POCI-01-0145-FEDER-007638)
文摘Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios.
文摘A field study was conducted at the Agricultural Research Farm of Razi University, Kermanshah, Iran to investigate the effects of phosphate biofertilizer, row spacing and plant density on corn yield and weed growth. The experiment was a factorial with three factors arranged in a randomized complete block design with three replications. The first factor was phosphate biofertilizer (inoculation and non-inoculation), the second was row spacing (conventional (75 cm) and reduced (50 cm)) and the third was plant density (66,666 plants·ha–1 (conventional plant density) 83,333 and 99,999 plants·ha–1 (1.25 and 1.5 times the conventional plant density, respectively)). Results indicated that corn yield and weed growth were significantly influenced by row spacing and plant density. So that, corn yield improved and weed biomass diminished in response to increasing plant density and decreasing row spacing. However, phosphate biofertilizer had no significant effect on corn yield, whereas, weed biomass was notably increased when phosphate biofertilizer was applied. Overall, this study revealed that both yield and weed control in corn field can be improved by alteration of the planting arrangement.
基金supported by the project ‘‘Impact of Climatic Change and Agricultural Activity on the Emission of Greenhouse Gases and on the Microbial Resources of the Sierra Nevada,Mexico’’[‘‘Impacto del Cambio Climáticos y actividad agrícola en la emisión de gases de efecto invernadero y en los recursos microbianos de la Sierra Nevada,México’’] No.213059funded by the National Council of Science and Technology [Consejo Nacional de Ciencia y Tecnología(CONACy T)]
文摘In this study,10 bacterial strains were isolated from the rhizosphere of coniferous trees on Mount Tla′loc in Mexico.The strains were characterized by their capacity to produce auxins,solubilize phosphates and stimulate mycelial growth of the ectomycorrhizal fungus Suillus sp.All isolates were identified at the molecular level.Moreover,an experiment was established to evaluate the response of Pinus pseudostrobus seedlings to inoculation with the rhizobacteria strains.The isolated strains belonged to the species Cupriavidus basilensis,Rhodococcus qingshengii,R.erythropolis,Pseudomonas spp.,P.gessardii,Stenotrophomonas rhizophila and Cohnella sp.All of the strains produced auxins;the best producer was R.erythropolis CPT9(76.4 lg mL^-1).P.gessardii CPT6 solubilized phosphate at a significant level(443 lg mL^-1).The strain S.rhizophila CPT8 significantly increased the radial growth of the ectomycorrhizal fungus Suillus sp.by 18.8%.Five strains increased the dry mass of the shoots;R.qingshengii CPT4 and R.erythropolis CPT9 increased growth the most,by more than 20%.Inoculation with plant-growth-promoting rhizobacteria can be a very useful practice in a forest nursery to produce healthy,vigorous plants.
文摘Silicon(Si)is the second most abundant element in the Earth’s crust and has numerous roles in both soils and plants,although it is inaccessible to plants in its native state(insoluble silicate minerals).This inaccessibility can lead to insufficiency,which induces anomalies in plant growth and development.Specifically,Si alleviates various biotic and abiotic stresses in plants by enhancing tolerance mechanisms at different stages of uptake/deposition as a monosilicic acid.Exclusive utilization of conventional Si fertilizers to boost agricultural productivity in an attempt to meet the world’s ever-increasing food demand may result in surface and groundwater pollution,waterway eutrophication,soil fertility depletion,and accumulation of hazardous elements such as arsenic in soil.By addressing the drawbacks of chemical fertilizers,this review emphasizes an environmentally friendly alternative,namely,Si-solubilizing microorganisms(SSMs),as bioinoculants to liberate soluble Si and thus making it available to plants.A deep understanding of recent advances in the functional diversity,colonization patterns,modes of action,role in biogeochemical cycling,and plant stress tolerance of SSMs and their implementation in Si-based agrowaste management through the fabrication of nanoparticles,could help to establish a reliable tool for economically and environmentally sustainable agriculture.From this perspective,in this review,we comprehensively summarize the latest methodologies for the isolation,screening,and characterization of SSMs and Si solubilization mechanisms,including ligands(divalent cations),acids(inorganic and organic),alkali(nucleophilic attack),extracellular polysaccharides,and factors affecting them,as well as Si-mediated regulation of gene expression involved in Si uptake,transportation,and mineralization.We have critically revised the role of SSMs according to the current literature.The contributions of SSMs to biofertilization are still being explored;hence,we also discuss trajectories for future research in relation to SSM-mediated increases in bioavailable Si.This will create new strategies to reduce the use of agrochemicals,improve plant health,and help us to globally gravitate towards more sustainable agricultural practices,based on the concept of a circular economy.
基金supported by the National Science Fund Projects (Nos. 41371266 and 31670507)Innovation in Cross-functional Team Program of the Chinese Academy of Sciences (No. 2015)+1 种基金the Key Research Program of Chinese Academy of Sciences (No. ZDRW-ZS-2016-5)the Key State Science and Technology Program of China (No. 2015ZX07206-006)
文摘Ammonia（NH3） volatilization is one of the primary pathways of nitrogen（N） loss from soils after chemical fertilizer is applied, especially from the alkaline soils in Northern China, which results in lower efficiency for chemical fertilizers. Therefore, we conducted an incubation experiment using an alkaline soil from Tianjin（p H 8.37–8.43） to evaluate the suppression effect of Trichoderma viride（T. viride） biofertilizer on NH3 volatilization, and compared the differences in microbial community structure among all samples. The results showed that viable T. viride biofertilizer（T） decreased NH3 volatilization by 42.21% compared with conventional fertilizer（（CK）, urea）, while nonviable T. viride biofertilizer（TS） decreased NH3 volatilization by 32.42%. NH3 volatilization was significantly higher in CK and sweet potato starch wastewater（SPSW） treatments during the peak period. T. viride biofertilizer also improved the transfer of ammonium from soil to sweet sorghum. Plant dry weights increased 91.23% and 61.08% for T and TS, respectively, compared to CK. Moreover, T. viride biofertilizer enhanced nitrification by increasing the abundance of ammonium-oxidizing archaea（AOA） and ammonium-oxidizing bacteria（AOB）. The results of high-throughput sequencing indicated that the microbial community structure and composition were significantly changed by the application of T. viride biofertilizer. This study demonstrated the immense potential of T. viride biofertilizer in reducing NH3 volatilization from alkaline soil and simultaneously improving the utilization of fertilizer N by sweet sorghum.
文摘Myo-inositol phosphates (phytates) are important biological molecules produced largely by plants to store phosphorus. Phytate is very abundant in many different soils making up a large portion of all soil phosphorus. This review assesses current phytase science from the perspective of its substrate, phytate, by examining the intricate relationship between the phytate-hydrolyzing enzymes and phytate as their substrate. Specifically, we examine available data on phytate’s structural features, distribution in nature and functional roles. The role of phytases and their localization in soil and plant tissues are evaluated. We provide a summary of the current biotechnological advances in using industrial or recombinant phytases to improve plant growth and animal nutrition. The prospects of future discovery of novel phytases with improved biochemical properties and bioengineering of existing enzymes are also discussed. Two alternative but complementary directions to increase phosphorus bioavailability through the more efficient utilization of soil phytate are currently being developed. These approaches take advantage of microbial phytases secreted into rhizosphere either by phytase-producing microbes (biofertilizers) or by genetically engineered plants. More research on phytate metabolism in soils and plants is needed to promote environmentally friendly, more productive and sustainable agriculture.
