Modern agribusiness plays a vital role in safeguarding and improving the production,quality,and quantity of food,feed,fiber,and fuel.Growing concerns over the impact of chemical pesticides on health and the environmen...Modern agribusiness plays a vital role in safeguarding and improving the production,quality,and quantity of food,feed,fiber,and fuel.Growing concerns over the impact of chemical pesticides on health and the environment have stimulated the industry to search for alternative and greener solutions.Over the last years,the RNA interference(RNAi)process has been identified as a very promising new approach to complement the arsenal of foliar spray,soil,or seed treatments applied as chemical and biological pest control agents,and of plant-incorporated protectants(PIPs).RNA-based active ingredients(AIs)possess a unique mode of action and can be implemented via both genetic modification(GM)and biocontrol approaches.RNA-based AIs promise to deliver the selectivity and sustainability desired in future crop protection agents.This is due to their utilization of a natural process to exert control and their high level of selectivity,which leads to reduced risk for non-target organisms(NTOs).This review discusses the advantages and limitations of RNA-based solutions in crop protection and recent research progress toward RNA-based biocontrols against the Colorado potato beetle(CPB),corn rootworm(CRW),and soy stink bug(SSB).Many challenges still exist on the road to the implementation of a broad range of RNA-based products and their widespread use and application.Despite these challenges,it can be expected that RNA-based AIs will become valuable new tools complementing the current arsenal of crop-protection solutions.展开更多
Bemisia tabaci is a polyphagous herbivore that feeds on a wide range of horticultural and ornamental crops cultivated under diverse ecological zones. In Sierra Leone, B. tabaci is found to infest a wide range of veget...Bemisia tabaci is a polyphagous herbivore that feeds on a wide range of horticultural and ornamental crops cultivated under diverse ecological zones. In Sierra Leone, B. tabaci is found to infest a wide range of vegetable crops by directly feeding on phloem sap thereby inducing physiological disorders, and also serve as a vector to gemini viruses. Invariably the destructive feeding of B. tabaci affects the productivity and aesthetic values of vegetables and other horticultural crops and hence is considered a serious economic pest. A bioassay experiment was carried out by rearing B. tabaci populations on four vegetable crops under controlled laboratory conditions to determine its life table and demographic parameters. Results showed that the intrinsic rate of growth which measures the population size and growth pattern was highest for populations reared on tomato crops with the following values: rm 0.145 female female−1 day−1, the gross reproduction rate (Ro), and finite growth rate λ were highest for population reared on tomato, correspondingly the development period from egg-adult emergence was shortest with a value of 26 d. Conversely, the computed demographical parameters rm, λ and Ro for the population reared on sweet pepper were 0.106 female female−1 day−1 respectively, with a corresponding development period egg-adult emergence as 36d. The computed biological parameters for okra and garden egg varied with intermediary values between tomato and pepper host materials. The survivorship rates were quite significant for the smaller instars (Instars 1-III) with over 80% surviving to pre-pupa and pupa stage for the populations reared for all the test materials. High mortality was noticed for the pre-pupa and pupa stages as their survival rates were significantly low compared to the high survival rates of the smaller instars. Less than 50% of pupae failed to emerge to adults except for populations reared on tomato test materials where 52% emerged to adults. The study indicated tomato as the most suitable host among the four vegetable crops. Although life table and demographic parameters are invaluable information for forecasting pest populations and help in designing pest management efforts, further investigations such as the economic threshold and economic injury levels of B. tabaci population are requisite decision tools for sound pest management decisions of B. tabaci on these vegetable crops. The information obtained from this investigation would be quite relevant for extension service and pest management practitioners where mixed vegetable farming is a common practice.展开更多
The Conservation Agriculture (CA) is a current concept drives to save natural resources for agricultural production based on the minimum soil disturbance or no-tillage, crop rotation and permanent maintenance of straw...The Conservation Agriculture (CA) is a current concept drives to save natural resources for agricultural production based on the minimum soil disturbance or no-tillage, crop rotation and permanent maintenance of straw on soil surface. The increasing in soil density is a problem to achieve great copping yield under CA, so occasional one-time tillage is considered as an alternative to continuous no-tillage. In this way, this experiment was carried out to compare occasional tillage and no-tillage interacting with cover crops in a field established under conservation agriculture. Thus, the experimental treatments were set up by two tillage methods, conventional tillage and no-tillage and two cover crops, white lupin and millet setting in a randomized blocks with split plot design with four replications. The traits evaluated in the research were soil fertility, soil resistance to penetration, soil moisture and tomato agronomic performance. No-tillage was more efficient to preserve soil moisture;however soil fertility, soil resistance to penetration and tomato yield were favored by conventional tillage. Regarding to cover crops white lupin increased the soil K concentration and enhanced the tomato growth. Although occasional tillage had better performance to the soil fertility and tomato yield, we highlighted that CA is the better way to increase soil health and soil and water conservation along the time leading to so desired regenerative agriculture.展开更多
Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we e...Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.展开更多
Peanut(Arachis hypogaea),which is widely cultivated across the world,provides high-quality vegetable oil,protein,dietary fiber,minerals,and vitamins for humans.However,in field conditions,the peanut is easily affected...Peanut(Arachis hypogaea),which is widely cultivated across the world,provides high-quality vegetable oil,protein,dietary fiber,minerals,and vitamins for humans.However,in field conditions,the peanut is easily affected by various biotic and abiotic stresses.Diplodia gossypina is the dominant pathogen causing severe collar rot on peanuts.To dissect the pathogenic mechanism of D.gossypina,genome sequencing analysis was performed by using the D.gossypina strain A20_4.The sequencing data showed that the genome assembly size of D.gossypina A20_4 is 43.03 Mb with a GC content of 54.91%.The de novo assembly identified a total of 10,745 genes,containing 41,526 coding sequences and 2.20%of repeat sequences,of which 6,461 genes(60.13%)were annotated using BlastP from GO annotation,3,245 genes(30.20%)and 3,093 genes(28.79%)were annotated from KOG and KEGG annotations,respectively.Meanwhile,the secreted proteins and effectors in 10,745 protein sequences encoded by the whole genome of D.gossypina A20_4 were analyzed,and the results showed that there are 790 secreted protein genes including 220 carbohydrate-active enzymes and 224 potential effector proteins.The functions of 222 potential effector proteins can be annotated by PHI-base.According to the annotation results,12 key pathogenic factors were identified in D.gossypina A20_4.Moreover,a serine/threonine protein kinase SNF1 gene required for autophagy process was identified and analyzed.Deciphering the whole genome of D.gossypina A20_4 provides us with novel insights into understanding evolution,pathogenic molecular mechanism,host-pathogen interaction,and many other complexities of the pathogen.展开更多
Tephritid fruit flies are considered one of the world’s most notorious pests of horticultural crops, including mango (Mangefera indica L.) in Sierra Leone, causing extensive direct and indirect damage. A survey was c...Tephritid fruit flies are considered one of the world’s most notorious pests of horticultural crops, including mango (Mangefera indica L.) in Sierra Leone, causing extensive direct and indirect damage. A survey was conducted among 60 mango farmers in 7 districts in Sierra Leone between June and August, 2022, to assess their perceptions regarding fruit fly pest status and the current management options adopted for the control of this pest. Semi-structured questions designed in an open and closed-ended fashion were used for the study. The majority (83%) of the farmers were already aware of the fruit fly problem in the country with 62% perceiving it to be very severe. The majority (60%) of farmers, however, demonstrated poor knowledge of identifying fruit fly species, especially Bactrocera dorsalis, Ceratitis capitata, and Ceratitis cosyra. Farmers were more conversant about the direct damage symptoms to host fruits and the economic impact of fruit flies. A total of 32% of growers took no action to control fruit flies on their farms. Sixty-nine percent (69%) of the farmers adopted cultural control measures, like practicing prompt harvesting, collection and disposal of infested fruits, and weeding to maintain better sanitary conditions on their farms. Recommended fruit fly management strategies such as the use of botanicals and resistant varieties were either unknown or inaccessible to growers. A total of 52% applied chemicals that were not recommended for the control of fruit flies without considering their environmental and health risks. It is important to train fruit growers to improve their capabilities for fruit fly management through extension agents that are appropriate for helping them acquire basic knowledge of fruit fly pests and their management.展开更多
[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications....[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications.Each treatment was administered at the recommended dosages.[Results]The application of Metalaxyl-M·Fludioxonil+amino acids demonstrated a control efficacy of 93.65%against root rot in tobacco floating seedlings.In comparison,the application of Metalaxyl-M·Fludioxonil alone exhibited a control efficacy of 88.42%.The most effective treatment for promoting root growth in tobacco seedlings was Metalaxyl-M·Fludioxonil+amino acids,which resulted in a 54.65%increase in root growth compared to the blank control.This was followed by the application of Metalaxyl-M·Fludioxonil alone,which yielded a 39.53%increase in root growth relative to the blank control.[Conclusions]The application of Metalaxyl-M·Fludioxonil+amino acids is recommended for use in the seedling pools of tobacco seedling cultivation.Specifically,it is advised to incorporate 1 mL of Metalaxyl-M·Fludioxonil and 2 mL of amino acids into each seedling tray prior to their introduction into the seedling pool.This treatment has demonstrated significant efficacy in preventing and controlling root rot in tobacco floating seedlings,while also promoting the health of the root system and ensuring the quality of transplanted tobacco seedlings.展开更多
The use of plant extracts as insecticides against vector insects serves as a perfect alternative to conventional methods.This study was carried out to assess the chemical composition and efficacy of Chromolaena odorat...The use of plant extracts as insecticides against vector insects serves as a perfect alternative to conventional methods.This study was carried out to assess the chemical composition and efficacy of Chromolaena odorata L.and Ocimum gratissimum L.in the control of adult houseflies.C.odorata and O.gratissimum were extracted with cold water and applied at four concentrations(5,10,40 and 100%v/v)in different bioassays(contact,fumigant and feeding-deterrent).A synthetic insecticide(Lambdacyhalothrin)and an untreated control were included in the treatments.The treatments were arranged in a completely randomized design with three replicates.The phytochemical compositions of the tested plant extracts were determined via gas chromatography‒mass spectrometry(GC‒MS).Mortality data were recorded at the stipulated times(1,2,4,6,8 and 24 h),and the means were separated via Duncan’s multiple range test at a 5%probability.GC‒MS revealed different chemical compounds,and eugenol,n-hexadecanoic acid,caryophyllene,phytol,humulene,9,12,15-octadecatrienoic acid,(Z,Z,Z)-,squalene,and stigmasterol compounds,among others,were identified as active insecticidal compounds.The tested plant extracts were effective against the studied insects,which suggested synergistic action of the observed natural chemicals in the plant extracts used.Moreover,the two plant extracts did not kill the studied insects faster than the synthetic insecticide did,but 100%mortality was observed after 12 h of exposure to the plant extracts.The mode of application and concentration played a significant role in the toxicity of the plant extracts,with the feeding mode of application resulting in greater toxicity effects than the fumigant and contact bioassays at the highest concentration.However,O.gratissimum exhibited better insecticidal control than C.odorata extracts did.Therefore,the use of crude plant extracts as insecticides could serve as substitutes for lambdachyalothrin in the control of houseflies,especially in animal rearing facilities and in the human population.展开更多
Use of synthetic pesticides to manage crop pests has had a toll on human health, environmental safety and farmer’s income creating a need for alternative crop protection strategies. Botanical pesticides have been rep...Use of synthetic pesticides to manage crop pests has had a toll on human health, environmental safety and farmer’s income creating a need for alternative crop protection strategies. Botanical pesticides have been reported to be effective in managing crop pests, and a number of them have been formulated and commercialized. This study was conducted in North-Eastern Tanzania to establish the pesticidal and medicinal value of turmeric (Curcuma longa) and ginger (Zingiber officinale). Purposive sampling was adopted to select and interview 167 respondents drawn from farmers, traders, pharmaceutical shops, agro-shop operators and consumers of turmeric and ginger. Ginger and turmeric rhizomes were also collected for extraction, antifungal assay and biochemical analysis. Results showed that majority of the respondents were aware of the medicinal value of ginger and turmeric, with 59.5% having used the plants to treat respiratory related infections and healing skin surface and internal wounds. About 14% of farmers were aware of and had used aqueous botanical preparations from neem, moringa and Tephrosia to manage insect pests. Only 2.7% of farmers had used ginger powder as a protective insecticide on stored grains. Ginger and turmeric rhizome extracts showed high antifungal activity against Pythium (83% - 95%), Fusarium oxysporum f. sp. lycopersici (34% - 52%) and Alternaria solani (38% - 53%). A GC-MS analysis of ginger and turmeric extracts showed presence of α-zingiberene, β-sesquiphellandrene, α-farnesene, ar-curcumene, α-copaene, ar-tumerone and curlone. This study recommends that ginger and turmeric extracts be considered for development of a botanical pesticide and especially for management of damping off diseases.展开更多
Background The pink bollworm(Pectinophora gossypiella,PBW)is a major cotton pest,causing economic losses by damaging seeds and fiber.Cotton growers typically use systemic and broad-spectrum insecticides for its manage...Background The pink bollworm(Pectinophora gossypiella,PBW)is a major cotton pest,causing economic losses by damaging seeds and fiber.Cotton growers typically use systemic and broad-spectrum insecticides for its manage-ment,which pose risks to human health and the environment.Consequently,there is a need for eco-friendly alterna-tives.This study evaluates the bio-efficacy of the entomopathogenic fungus Metarhizium anisopliae strain TMBMA1 against pink bollworm and assesses its compatibility with major insecticides.Additionally,to comprehend the dynam-ics of colonization and the infection processes of entomopathogenic fungi(EPF),scanning electron microscopy(SEM)of infected larvae was carried out.Result We challenged the second instar PBW larvae to eight different concentrations(1×10^(3) to 1×10^(10) conidia mL^(-1))of an M.anisopliae strain TMBMA1.The highest mortality(100%)occurred at the higher concentrations i.e.,1×109 and 1×10^(10) spores mL^(-1),while the lowest mortality rate(46.6%)was observed at 1×10^(3) spores mL^(-1) con-centration compared to control(3.33%).TMBMA1’s biocontrol efficacy was validated by Probit analysis,exhibiting an exceptionally low median lethal concentration(LC50)value of 7.1×10^(5).The comparative evaluation revealed that the M.anisopliae strain TMBMA1 performed excellently with insecticide[Cypermethrin 10%(volume fraction)emulsifiable concentrate(EC)at 1 mL·L^(-1) water]giving 100%mortality,both being superior to a commercial prod-uct of M.anisopliae(60%).According to SEM analysis,the EPF strain was profusely colonized on both the internal and external surfaces of PBW larvae.Compatibility studies with insecticides revealed>98%and>96%reduction in the sporulation of M.anisopliae due to the treatment of Emamectin Benzoate 1.5%(mass fraction)+Profenofos 35%(mass fraction)water dispersible granules(WDG)and Profenofos 50%EC,respectively.In contrast,Cypermethrin 10%EC,Emamectin Benzoate 5%(mass fraction)Soluble Granules and Neem Seed Kernel Extract(NSKE)0.15%(volume fraction)treatments reported lower reduction(11.45%,13.79%and 21.21%respectively)in spore production.Conclusion According to the current investigations,the M.anisopliae strain TMBMA1 exhibits high virulence against PBW and offers a promising eco-friendly solution for managing this pest.It shows significant potential to pro-liferate on both external and internal surfaces of PBW.This strain can be integrated into PBW management programs with chemical insecticides,improving pest control and lessening environmental impact.展开更多
Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,...Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice.展开更多
A substantial body of research has been conducted with the objective of enhancing the understanding of Non-Timber Forest Products (NTFP) in Central Africa. A significant proportion of the studies focus on medicinal pl...A substantial body of research has been conducted with the objective of enhancing the understanding of Non-Timber Forest Products (NTFP) in Central Africa. A significant proportion of the studies focus on medicinal plants, in contrast to those that examine food products. Nevertheless, studies on edible wild mushrooms as NTFPs and cultivated mushrooms, on their economic potential and value chains in the Great Lakes Region, remain scarce and largely absent for some NTFPs. In light of the aforementioned considerations, the present study aims to examine the economic potential and value chain of the production sector of wild edible mushrooms (WEM) and cultivated mushrooms (CM) within the Virunga National Park (PNVi) and its surrounding areas in North Kivu, Democratic Republic of the Congo (DRC). To this end, a sample of 432 respondents was selected, distributed equitably among the actors of the Goma-Kitshanga-Mweso value chain, the Goma-Rutshuru chain, the Beni-Mutwanga chain, and the Beni-Mangina chain. A digital questionnaire consisting of open and closed questions was administered, and observations were carried out concurrently. The quantities of mushrooms sold were weighed and photographed. The results demonstrated that, when the eight-month fruiting period of wild and cultivated mushrooms was considered as a single year for all actors within the value chain, a picker could sell 6.1 kg at $2 and earn $12. A seller could sell 16 kg at $4 and earn $64, while a grower could sell 502 kg at $3 and earn $1506. Consequently, the CM grower generates a significantly higher profit than other participants in the value chain, despite the expenses he incurs. Ultimately, the domestication of WEM, highly prized by the local population of the Virunga National Park, has the potential to enhance their household incomes, as evidenced by the findings of this study.展开更多
Wheat streak mosaic virus（WSMV）has become a re-emerging pathogen in cereal crops in the Czech Republic.WSMV was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was docu...Wheat streak mosaic virus（WSMV）has become a re-emerging pathogen in cereal crops in the Czech Republic.WSMV was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was documented until 2009.The incidence of the virus was recorded in recent years in several winter wheat fields and many grass species.Here,we surveyed the incidence of WSMV in cereal crops.The results demonstrated the existence of the virus in winter wheat and volunteer wheat during each year of the monitoring period,which spanned from 2013–2016.Although the range of infected samples was low（6.4%of the total tested samples）,a high incidence of well-distributed virus was recorded.In at least six fields,the virus reached severe and potentially epidemic levels.In accordance with our previous report detailing WSMV infection of native grasses,we tested several grass species commonly grown in the Czech Republic.We found that some grass species acted as experimental hosts and possible reservoirs of the virus;these included Anthoxanthum odoratum（sweet vernal grass）,Arrhenatherum elatius（false oat-grass）,Lolium multiflorum（Italian rye-grass）,Bromus japonicus（Japanese chess）,Echinochloa crus-galli（barnyard grass）,Holcus lanatus（meadow soft grass）and Holcus mollis（creeping soft grass）.Some of these grass species are also important weeds of cereals,which may be the potential source of WSMV infection in cereal crops.Several widely used winter wheat cultivars were tested in the field after artificial inoculation with WSMV to evaluate virus titre by RT-qPCR.Overall,the tested cultivars had a low virus titre,which is associated with mild disease symptoms and may provide a good level of crop resistance to WSMV.展开更多
Sharka caused by Plum pox virus（PPV）is the most harmful disease of stone fruits in Europe and elsewhere in the world.There is no highly PPV resistant cultivar of plum.Biotech approach has led to the development of r...Sharka caused by Plum pox virus（PPV）is the most harmful disease of stone fruits in Europe and elsewhere in the world.There is no highly PPV resistant cultivar of plum.Biotech approach has led to the development of resistance through genetic engineering.In this study,we evaluated a transgenic plum Prunus domestica L.,clone C5（cv.Honey Sweet）,where the PPV resistance is based on RNA interference（RNAi）.Resistance in C5 plums has been evaluated for PPV,Prune dwarf virus（PDV）,and Apple chlorotic leaf spot virus（ACLSV）in a regulated field trial in the Czech Republic for 12 years（2002–2013）.Even under high and permanent infection pressure introduced through graft inoculation of the viruses,PPV has been detected in C5 trees only in several leaves situated close to the point of inoculum grafting in the first nine years.Mild symptoms of PPV disappeared year by year.No PPV symptoms were observed in the last three years and results of ELISA detection were negative.Similar results were obtained,when RT-PCR was used for PPV detection.No natural infection of PPV by aphids was recorded in C5 plums,even if PPV infected plants were growing in the same experimental field in close vicinity.Co-infections of PPV with PDV and/or ACLSV had practically no influence on stability of resistance in C5 trees.Twelve years of field testing in the Czech Republic clearly demonstrated the high level of resistance of C5 either to PPV infection by graft inoculation or natural infection through aphid vectors.展开更多
Fields experiments were conducted at the Department of Crop Protection, Faculty of Agriculture, University of Maiduguri Teaching and Research Farm, Maiduguri during 2010 and 2011 cropping seasons to investigate the ef...Fields experiments were conducted at the Department of Crop Protection, Faculty of Agriculture, University of Maiduguri Teaching and Research Farm, Maiduguri during 2010 and 2011 cropping seasons to investigate the effects of intercropping pattern on stem borer pest infestation in pearl millet (Pennisetum glaucum L.) intercropped with ground nut (Arachis hypogea L.). A split-plot design was used to test the intercrop pattern of 1:0 ratio (sole millet), 1:1 ratio (1 millet row to 1 ground nut row), 2:1 ratio (2 millet rows to 1 ground nut row) and 1:2 ratio (1 millet row to 2 ground nut rows). The results obtained showed that the intercrop pattern of 1:2 ratio and 1:1 ratio yielded less stem borer infestation and abundance in pearl millet, and as well supported high panicle weight and grain yield. In addition to recommending either of these two intercropping patterns to pearl millet farmers for more effective stem borer pest management, results further show the need for identification of effective intercropping patterns in other cropping systems.展开更多
The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of inter...The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of interest and costly techniques may be used to measure them. It is therefore important to know which soil parameters need to be determined. It can be stated that those which affect significantly the output variable deserve an accurate determination while those which slightly affect the model output variable do not. This paper demonstrates how a global sensitivity analysis method based on variance decomposition can be applied on soil parameters in order to divide them in the two categories. The Extended FAST method applied to the crop model STICS and a set of 13 soil parameters first allows to calculate the part of variance explained by each soil parameter (giving global sensitivity indices of the soil parameters) and the coefficient of variation of the output variables (measuring the effect of the parameter uncertainty on each variable). These metrics are therefore used for deciding on the importance of the parameter value measurement. Different output variables (Leaf Area Index and chlorophyll content) are evaluated at different stages of interest while others (crop yield, grain protein content, soil mineral nitrogen) are evaluated at harvest. The analysis is applied on two different annual crops (wheat and sugar beet), two contrasted weather and two types of soil depth. When the uncertainty of the output generated by the soil parameters is large (coefficient of variation > 1/3), only the parameters having a significant global sensitivity indices (higher than 10%) are retained. The results show that the number of soil parameters which deserve an accurate determination can be significantly reduced by the use of this relevant method for appropriate management decision support.展开更多
In a long term study photosynthetically active radiation was monitored for three rainy seasons to measure the effects of hedgerow intercropping in rotation with maize and cowpea in a senna/siamea and panicum/grass str...In a long term study photosynthetically active radiation was monitored for three rainy seasons to measure the effects of hedgerow intercropping in rotation with maize and cowpea in a senna/siamea and panicum/grass strip on biomass yield and light use efficiency. Maize/cowpea intercropped with senna siamea or grass stripped were compared with sole maize and cowpea. A ceptometer was applied to measure PAR interception by sole maize or cowpea or crop/tree and grass/crop interfaces and separation of PAR used by each plant or tree/grass component. Hedgerow intercropping increased PAR interception and biomass formation. C4 plants had higher LUE than C3 plants while combining C4 and C3 in the agroforestry system lowered LUE. The tree/crop interfaces increased PAR interception than at 1 m and 2 m away from the hedgerow. The row of maize or cowpea at lm intercepted more PAR than the row at 2 m from hedgerow while the cowpea row next to the hedgerow was depressed compared to the rows in the middle rows which had higher yields. The maize or cowpea row next to the grass strip was more stressed than the rows in the middle of the alley.展开更多
There is an urgent necessity to shift our diets toward those rich in fruits and vegetables and at reduce postharvest losses of perishables.Approximately 20%-50%of fruits and vegetables are lost due to poor postharvest...There is an urgent necessity to shift our diets toward those rich in fruits and vegetables and at reduce postharvest losses of perishables.Approximately 20%-50%of fruits and vegetables are lost due to poor postharvest handling and pathogen infections in developing countries while it was estimated as 5%-35%in developed countries. Fresh fruits have evolved with a plethora of microorganisms having important roles in maintaining fruit health. However, little information is available on the dynamics, structure, and functional capacities of underpinning fruit microbiomes. The present review discussed environmental conditions favoring fruit-harbored antagonists and their different modes of action for suppressing postharvest pathogens in fruits. It also provides information on omics technologies such as next-generation sequencing (NGS),metaproteomics, metatranscriptomic, and metabolomics studies to characterize fruit microbiomes. With the advent of NGS and meta-omics technologies, microbiome research could bring remarkable development and understanding in succeeding biological treatments. In addition, they may provide us with a fundamental understanding of microclimate requirements for fruit microbiome establishment and microbiome shifts during post-harvest storage, which would be advantageous in developing composite biocontrol treatments for post-harvest decay management.展开更多
The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome edit...The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.展开更多
The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, c...The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, cost-effectiveness, and a prolonged shelf life. Controlling the drying process is crucial for ensuring the stability and durability of the product. The traditional approach, which involved mechanical and natural drying, led to decreased productivity and quality. The objective of this research endeavour was to achieve a dry process enhancement while preserving the microbial quality of Trichoderma asperellum (M103). The temperature and relative humidity during the drying period were monitored under two conditions: with and without a dehumidifier. The results demonstrate that the dehumidifier increases drying period efficiency by up to 63%.展开更多
文摘Modern agribusiness plays a vital role in safeguarding and improving the production,quality,and quantity of food,feed,fiber,and fuel.Growing concerns over the impact of chemical pesticides on health and the environment have stimulated the industry to search for alternative and greener solutions.Over the last years,the RNA interference(RNAi)process has been identified as a very promising new approach to complement the arsenal of foliar spray,soil,or seed treatments applied as chemical and biological pest control agents,and of plant-incorporated protectants(PIPs).RNA-based active ingredients(AIs)possess a unique mode of action and can be implemented via both genetic modification(GM)and biocontrol approaches.RNA-based AIs promise to deliver the selectivity and sustainability desired in future crop protection agents.This is due to their utilization of a natural process to exert control and their high level of selectivity,which leads to reduced risk for non-target organisms(NTOs).This review discusses the advantages and limitations of RNA-based solutions in crop protection and recent research progress toward RNA-based biocontrols against the Colorado potato beetle(CPB),corn rootworm(CRW),and soy stink bug(SSB).Many challenges still exist on the road to the implementation of a broad range of RNA-based products and their widespread use and application.Despite these challenges,it can be expected that RNA-based AIs will become valuable new tools complementing the current arsenal of crop-protection solutions.
文摘Bemisia tabaci is a polyphagous herbivore that feeds on a wide range of horticultural and ornamental crops cultivated under diverse ecological zones. In Sierra Leone, B. tabaci is found to infest a wide range of vegetable crops by directly feeding on phloem sap thereby inducing physiological disorders, and also serve as a vector to gemini viruses. Invariably the destructive feeding of B. tabaci affects the productivity and aesthetic values of vegetables and other horticultural crops and hence is considered a serious economic pest. A bioassay experiment was carried out by rearing B. tabaci populations on four vegetable crops under controlled laboratory conditions to determine its life table and demographic parameters. Results showed that the intrinsic rate of growth which measures the population size and growth pattern was highest for populations reared on tomato crops with the following values: rm 0.145 female female−1 day−1, the gross reproduction rate (Ro), and finite growth rate λ were highest for population reared on tomato, correspondingly the development period from egg-adult emergence was shortest with a value of 26 d. Conversely, the computed demographical parameters rm, λ and Ro for the population reared on sweet pepper were 0.106 female female−1 day−1 respectively, with a corresponding development period egg-adult emergence as 36d. The computed biological parameters for okra and garden egg varied with intermediary values between tomato and pepper host materials. The survivorship rates were quite significant for the smaller instars (Instars 1-III) with over 80% surviving to pre-pupa and pupa stage for the populations reared for all the test materials. High mortality was noticed for the pre-pupa and pupa stages as their survival rates were significantly low compared to the high survival rates of the smaller instars. Less than 50% of pupae failed to emerge to adults except for populations reared on tomato test materials where 52% emerged to adults. The study indicated tomato as the most suitable host among the four vegetable crops. Although life table and demographic parameters are invaluable information for forecasting pest populations and help in designing pest management efforts, further investigations such as the economic threshold and economic injury levels of B. tabaci population are requisite decision tools for sound pest management decisions of B. tabaci on these vegetable crops. The information obtained from this investigation would be quite relevant for extension service and pest management practitioners where mixed vegetable farming is a common practice.
文摘The Conservation Agriculture (CA) is a current concept drives to save natural resources for agricultural production based on the minimum soil disturbance or no-tillage, crop rotation and permanent maintenance of straw on soil surface. The increasing in soil density is a problem to achieve great copping yield under CA, so occasional one-time tillage is considered as an alternative to continuous no-tillage. In this way, this experiment was carried out to compare occasional tillage and no-tillage interacting with cover crops in a field established under conservation agriculture. Thus, the experimental treatments were set up by two tillage methods, conventional tillage and no-tillage and two cover crops, white lupin and millet setting in a randomized blocks with split plot design with four replications. The traits evaluated in the research were soil fertility, soil resistance to penetration, soil moisture and tomato agronomic performance. No-tillage was more efficient to preserve soil moisture;however soil fertility, soil resistance to penetration and tomato yield were favored by conventional tillage. Regarding to cover crops white lupin increased the soil K concentration and enhanced the tomato growth. Although occasional tillage had better performance to the soil fertility and tomato yield, we highlighted that CA is the better way to increase soil health and soil and water conservation along the time leading to so desired regenerative agriculture.
基金financially funded by the National Natural Science Foundation of China(U2004205)the China Agricultural University-Syngenta Project.
文摘Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.
基金The Major Science and Technology Project of Henan Province(Grant No.201300111000)The Basic scientific Research Project of Henan Academy of Agricultural Sciences(Grant No.2022ZC37,2023ZC46)。
文摘Peanut(Arachis hypogaea),which is widely cultivated across the world,provides high-quality vegetable oil,protein,dietary fiber,minerals,and vitamins for humans.However,in field conditions,the peanut is easily affected by various biotic and abiotic stresses.Diplodia gossypina is the dominant pathogen causing severe collar rot on peanuts.To dissect the pathogenic mechanism of D.gossypina,genome sequencing analysis was performed by using the D.gossypina strain A20_4.The sequencing data showed that the genome assembly size of D.gossypina A20_4 is 43.03 Mb with a GC content of 54.91%.The de novo assembly identified a total of 10,745 genes,containing 41,526 coding sequences and 2.20%of repeat sequences,of which 6,461 genes(60.13%)were annotated using BlastP from GO annotation,3,245 genes(30.20%)and 3,093 genes(28.79%)were annotated from KOG and KEGG annotations,respectively.Meanwhile,the secreted proteins and effectors in 10,745 protein sequences encoded by the whole genome of D.gossypina A20_4 were analyzed,and the results showed that there are 790 secreted protein genes including 220 carbohydrate-active enzymes and 224 potential effector proteins.The functions of 222 potential effector proteins can be annotated by PHI-base.According to the annotation results,12 key pathogenic factors were identified in D.gossypina A20_4.Moreover,a serine/threonine protein kinase SNF1 gene required for autophagy process was identified and analyzed.Deciphering the whole genome of D.gossypina A20_4 provides us with novel insights into understanding evolution,pathogenic molecular mechanism,host-pathogen interaction,and many other complexities of the pathogen.
文摘Tephritid fruit flies are considered one of the world’s most notorious pests of horticultural crops, including mango (Mangefera indica L.) in Sierra Leone, causing extensive direct and indirect damage. A survey was conducted among 60 mango farmers in 7 districts in Sierra Leone between June and August, 2022, to assess their perceptions regarding fruit fly pest status and the current management options adopted for the control of this pest. Semi-structured questions designed in an open and closed-ended fashion were used for the study. The majority (83%) of the farmers were already aware of the fruit fly problem in the country with 62% perceiving it to be very severe. The majority (60%) of farmers, however, demonstrated poor knowledge of identifying fruit fly species, especially Bactrocera dorsalis, Ceratitis capitata, and Ceratitis cosyra. Farmers were more conversant about the direct damage symptoms to host fruits and the economic impact of fruit flies. A total of 32% of growers took no action to control fruit flies on their farms. Sixty-nine percent (69%) of the farmers adopted cultural control measures, like practicing prompt harvesting, collection and disposal of infested fruits, and weeding to maintain better sanitary conditions on their farms. Recommended fruit fly management strategies such as the use of botanicals and resistant varieties were either unknown or inaccessible to growers. A total of 52% applied chemicals that were not recommended for the control of fruit flies without considering their environmental and health risks. It is important to train fruit growers to improve their capabilities for fruit fly management through extension agents that are appropriate for helping them acquire basic knowledge of fruit fly pests and their management.
文摘[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications.Each treatment was administered at the recommended dosages.[Results]The application of Metalaxyl-M·Fludioxonil+amino acids demonstrated a control efficacy of 93.65%against root rot in tobacco floating seedlings.In comparison,the application of Metalaxyl-M·Fludioxonil alone exhibited a control efficacy of 88.42%.The most effective treatment for promoting root growth in tobacco seedlings was Metalaxyl-M·Fludioxonil+amino acids,which resulted in a 54.65%increase in root growth compared to the blank control.This was followed by the application of Metalaxyl-M·Fludioxonil alone,which yielded a 39.53%increase in root growth relative to the blank control.[Conclusions]The application of Metalaxyl-M·Fludioxonil+amino acids is recommended for use in the seedling pools of tobacco seedling cultivation.Specifically,it is advised to incorporate 1 mL of Metalaxyl-M·Fludioxonil and 2 mL of amino acids into each seedling tray prior to their introduction into the seedling pool.This treatment has demonstrated significant efficacy in preventing and controlling root rot in tobacco floating seedlings,while also promoting the health of the root system and ensuring the quality of transplanted tobacco seedlings.
文摘The use of plant extracts as insecticides against vector insects serves as a perfect alternative to conventional methods.This study was carried out to assess the chemical composition and efficacy of Chromolaena odorata L.and Ocimum gratissimum L.in the control of adult houseflies.C.odorata and O.gratissimum were extracted with cold water and applied at four concentrations(5,10,40 and 100%v/v)in different bioassays(contact,fumigant and feeding-deterrent).A synthetic insecticide(Lambdacyhalothrin)and an untreated control were included in the treatments.The treatments were arranged in a completely randomized design with three replicates.The phytochemical compositions of the tested plant extracts were determined via gas chromatography‒mass spectrometry(GC‒MS).Mortality data were recorded at the stipulated times(1,2,4,6,8 and 24 h),and the means were separated via Duncan’s multiple range test at a 5%probability.GC‒MS revealed different chemical compounds,and eugenol,n-hexadecanoic acid,caryophyllene,phytol,humulene,9,12,15-octadecatrienoic acid,(Z,Z,Z)-,squalene,and stigmasterol compounds,among others,were identified as active insecticidal compounds.The tested plant extracts were effective against the studied insects,which suggested synergistic action of the observed natural chemicals in the plant extracts used.Moreover,the two plant extracts did not kill the studied insects faster than the synthetic insecticide did,but 100%mortality was observed after 12 h of exposure to the plant extracts.The mode of application and concentration played a significant role in the toxicity of the plant extracts,with the feeding mode of application resulting in greater toxicity effects than the fumigant and contact bioassays at the highest concentration.However,O.gratissimum exhibited better insecticidal control than C.odorata extracts did.Therefore,the use of crude plant extracts as insecticides could serve as substitutes for lambdachyalothrin in the control of houseflies,especially in animal rearing facilities and in the human population.
文摘Use of synthetic pesticides to manage crop pests has had a toll on human health, environmental safety and farmer’s income creating a need for alternative crop protection strategies. Botanical pesticides have been reported to be effective in managing crop pests, and a number of them have been formulated and commercialized. This study was conducted in North-Eastern Tanzania to establish the pesticidal and medicinal value of turmeric (Curcuma longa) and ginger (Zingiber officinale). Purposive sampling was adopted to select and interview 167 respondents drawn from farmers, traders, pharmaceutical shops, agro-shop operators and consumers of turmeric and ginger. Ginger and turmeric rhizomes were also collected for extraction, antifungal assay and biochemical analysis. Results showed that majority of the respondents were aware of the medicinal value of ginger and turmeric, with 59.5% having used the plants to treat respiratory related infections and healing skin surface and internal wounds. About 14% of farmers were aware of and had used aqueous botanical preparations from neem, moringa and Tephrosia to manage insect pests. Only 2.7% of farmers had used ginger powder as a protective insecticide on stored grains. Ginger and turmeric rhizome extracts showed high antifungal activity against Pythium (83% - 95%), Fusarium oxysporum f. sp. lycopersici (34% - 52%) and Alternaria solani (38% - 53%). A GC-MS analysis of ginger and turmeric extracts showed presence of α-zingiberene, β-sesquiphellandrene, α-farnesene, ar-curcumene, α-copaene, ar-tumerone and curlone. This study recommends that ginger and turmeric extracts be considered for development of a botanical pesticide and especially for management of damping off diseases.
文摘Background The pink bollworm(Pectinophora gossypiella,PBW)is a major cotton pest,causing economic losses by damaging seeds and fiber.Cotton growers typically use systemic and broad-spectrum insecticides for its manage-ment,which pose risks to human health and the environment.Consequently,there is a need for eco-friendly alterna-tives.This study evaluates the bio-efficacy of the entomopathogenic fungus Metarhizium anisopliae strain TMBMA1 against pink bollworm and assesses its compatibility with major insecticides.Additionally,to comprehend the dynam-ics of colonization and the infection processes of entomopathogenic fungi(EPF),scanning electron microscopy(SEM)of infected larvae was carried out.Result We challenged the second instar PBW larvae to eight different concentrations(1×10^(3) to 1×10^(10) conidia mL^(-1))of an M.anisopliae strain TMBMA1.The highest mortality(100%)occurred at the higher concentrations i.e.,1×109 and 1×10^(10) spores mL^(-1),while the lowest mortality rate(46.6%)was observed at 1×10^(3) spores mL^(-1) con-centration compared to control(3.33%).TMBMA1’s biocontrol efficacy was validated by Probit analysis,exhibiting an exceptionally low median lethal concentration(LC50)value of 7.1×10^(5).The comparative evaluation revealed that the M.anisopliae strain TMBMA1 performed excellently with insecticide[Cypermethrin 10%(volume fraction)emulsifiable concentrate(EC)at 1 mL·L^(-1) water]giving 100%mortality,both being superior to a commercial prod-uct of M.anisopliae(60%).According to SEM analysis,the EPF strain was profusely colonized on both the internal and external surfaces of PBW larvae.Compatibility studies with insecticides revealed>98%and>96%reduction in the sporulation of M.anisopliae due to the treatment of Emamectin Benzoate 1.5%(mass fraction)+Profenofos 35%(mass fraction)water dispersible granules(WDG)and Profenofos 50%EC,respectively.In contrast,Cypermethrin 10%EC,Emamectin Benzoate 5%(mass fraction)Soluble Granules and Neem Seed Kernel Extract(NSKE)0.15%(volume fraction)treatments reported lower reduction(11.45%,13.79%and 21.21%respectively)in spore production.Conclusion According to the current investigations,the M.anisopliae strain TMBMA1 exhibits high virulence against PBW and offers a promising eco-friendly solution for managing this pest.It shows significant potential to pro-liferate on both external and internal surfaces of PBW.This strain can be integrated into PBW management programs with chemical insecticides,improving pest control and lessening environmental impact.
基金supported by the Director General,Indian Council of Agricultural Research(ICAR),New Delhithe Director,ICAR-National Rice Research Institute,Cuttack.
文摘Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice.
文摘A substantial body of research has been conducted with the objective of enhancing the understanding of Non-Timber Forest Products (NTFP) in Central Africa. A significant proportion of the studies focus on medicinal plants, in contrast to those that examine food products. Nevertheless, studies on edible wild mushrooms as NTFPs and cultivated mushrooms, on their economic potential and value chains in the Great Lakes Region, remain scarce and largely absent for some NTFPs. In light of the aforementioned considerations, the present study aims to examine the economic potential and value chain of the production sector of wild edible mushrooms (WEM) and cultivated mushrooms (CM) within the Virunga National Park (PNVi) and its surrounding areas in North Kivu, Democratic Republic of the Congo (DRC). To this end, a sample of 432 respondents was selected, distributed equitably among the actors of the Goma-Kitshanga-Mweso value chain, the Goma-Rutshuru chain, the Beni-Mutwanga chain, and the Beni-Mangina chain. A digital questionnaire consisting of open and closed questions was administered, and observations were carried out concurrently. The quantities of mushrooms sold were weighed and photographed. The results demonstrated that, when the eight-month fruiting period of wild and cultivated mushrooms was considered as a single year for all actors within the value chain, a picker could sell 6.1 kg at $2 and earn $12. A seller could sell 16 kg at $4 and earn $64, while a grower could sell 502 kg at $3 and earn $1506. Consequently, the CM grower generates a significantly higher profit than other participants in the value chain, despite the expenses he incurs. Ultimately, the domestication of WEM, highly prized by the local population of the Virunga National Park, has the potential to enhance their household incomes, as evidenced by the findings of this study.
基金supported by the grants from the Ministry of Agriculture, Czech Republic from projects QJ1230159 (50%) and RO0415 (50%)
文摘Wheat streak mosaic virus（WSMV）has become a re-emerging pathogen in cereal crops in the Czech Republic.WSMV was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was documented until 2009.The incidence of the virus was recorded in recent years in several winter wheat fields and many grass species.Here,we surveyed the incidence of WSMV in cereal crops.The results demonstrated the existence of the virus in winter wheat and volunteer wheat during each year of the monitoring period,which spanned from 2013–2016.Although the range of infected samples was low（6.4%of the total tested samples）,a high incidence of well-distributed virus was recorded.In at least six fields,the virus reached severe and potentially epidemic levels.In accordance with our previous report detailing WSMV infection of native grasses,we tested several grass species commonly grown in the Czech Republic.We found that some grass species acted as experimental hosts and possible reservoirs of the virus;these included Anthoxanthum odoratum（sweet vernal grass）,Arrhenatherum elatius（false oat-grass）,Lolium multiflorum（Italian rye-grass）,Bromus japonicus（Japanese chess）,Echinochloa crus-galli（barnyard grass）,Holcus lanatus（meadow soft grass）and Holcus mollis（creeping soft grass）.Some of these grass species are also important weeds of cereals,which may be the potential source of WSMV infection in cereal crops.Several widely used winter wheat cultivars were tested in the field after artificial inoculation with WSMV to evaluate virus titre by RT-qPCR.Overall,the tested cultivars had a low virus titre,which is associated with mild disease symptoms and may provide a good level of crop resistance to WSMV.
基金supported by the Ministry of Agriculture of the Czech Republic (QI101A123, QJ1610186 and RO 0415)
文摘Sharka caused by Plum pox virus（PPV）is the most harmful disease of stone fruits in Europe and elsewhere in the world.There is no highly PPV resistant cultivar of plum.Biotech approach has led to the development of resistance through genetic engineering.In this study,we evaluated a transgenic plum Prunus domestica L.,clone C5（cv.Honey Sweet）,where the PPV resistance is based on RNA interference（RNAi）.Resistance in C5 plums has been evaluated for PPV,Prune dwarf virus（PDV）,and Apple chlorotic leaf spot virus（ACLSV）in a regulated field trial in the Czech Republic for 12 years（2002–2013）.Even under high and permanent infection pressure introduced through graft inoculation of the viruses,PPV has been detected in C5 trees only in several leaves situated close to the point of inoculum grafting in the first nine years.Mild symptoms of PPV disappeared year by year.No PPV symptoms were observed in the last three years and results of ELISA detection were negative.Similar results were obtained,when RT-PCR was used for PPV detection.No natural infection of PPV by aphids was recorded in C5 plums,even if PPV infected plants were growing in the same experimental field in close vicinity.Co-infections of PPV with PDV and/or ACLSV had practically no influence on stability of resistance in C5 trees.Twelve years of field testing in the Czech Republic clearly demonstrated the high level of resistance of C5 either to PPV infection by graft inoculation or natural infection through aphid vectors.
文摘Fields experiments were conducted at the Department of Crop Protection, Faculty of Agriculture, University of Maiduguri Teaching and Research Farm, Maiduguri during 2010 and 2011 cropping seasons to investigate the effects of intercropping pattern on stem borer pest infestation in pearl millet (Pennisetum glaucum L.) intercropped with ground nut (Arachis hypogea L.). A split-plot design was used to test the intercrop pattern of 1:0 ratio (sole millet), 1:1 ratio (1 millet row to 1 ground nut row), 2:1 ratio (2 millet rows to 1 ground nut row) and 1:2 ratio (1 millet row to 2 ground nut rows). The results obtained showed that the intercrop pattern of 1:2 ratio and 1:1 ratio yielded less stem borer infestation and abundance in pearl millet, and as well supported high panicle weight and grain yield. In addition to recommending either of these two intercropping patterns to pearl millet farmers for more effective stem borer pest management, results further show the need for identification of effective intercropping patterns in other cropping systems.
文摘The use of a crop model like STICS for appropriate management decision support requires a good knowledge of all the parameters of the model. Among them, the soil parameters are difficult to know at each point of interest and costly techniques may be used to measure them. It is therefore important to know which soil parameters need to be determined. It can be stated that those which affect significantly the output variable deserve an accurate determination while those which slightly affect the model output variable do not. This paper demonstrates how a global sensitivity analysis method based on variance decomposition can be applied on soil parameters in order to divide them in the two categories. The Extended FAST method applied to the crop model STICS and a set of 13 soil parameters first allows to calculate the part of variance explained by each soil parameter (giving global sensitivity indices of the soil parameters) and the coefficient of variation of the output variables (measuring the effect of the parameter uncertainty on each variable). These metrics are therefore used for deciding on the importance of the parameter value measurement. Different output variables (Leaf Area Index and chlorophyll content) are evaluated at different stages of interest while others (crop yield, grain protein content, soil mineral nitrogen) are evaluated at harvest. The analysis is applied on two different annual crops (wheat and sugar beet), two contrasted weather and two types of soil depth. When the uncertainty of the output generated by the soil parameters is large (coefficient of variation > 1/3), only the parameters having a significant global sensitivity indices (higher than 10%) are retained. The results show that the number of soil parameters which deserve an accurate determination can be significantly reduced by the use of this relevant method for appropriate management decision support.
文摘In a long term study photosynthetically active radiation was monitored for three rainy seasons to measure the effects of hedgerow intercropping in rotation with maize and cowpea in a senna/siamea and panicum/grass strip on biomass yield and light use efficiency. Maize/cowpea intercropped with senna siamea or grass stripped were compared with sole maize and cowpea. A ceptometer was applied to measure PAR interception by sole maize or cowpea or crop/tree and grass/crop interfaces and separation of PAR used by each plant or tree/grass component. Hedgerow intercropping increased PAR interception and biomass formation. C4 plants had higher LUE than C3 plants while combining C4 and C3 in the agroforestry system lowered LUE. The tree/crop interfaces increased PAR interception than at 1 m and 2 m away from the hedgerow. The row of maize or cowpea at lm intercepted more PAR than the row at 2 m from hedgerow while the cowpea row next to the hedgerow was depressed compared to the rows in the middle rows which had higher yields. The maize or cowpea row next to the grass strip was more stressed than the rows in the middle of the alley.
基金the Deanship of Scientific Research,King Faisal University,Saudi Arabia(Grant No.5067).
文摘There is an urgent necessity to shift our diets toward those rich in fruits and vegetables and at reduce postharvest losses of perishables.Approximately 20%-50%of fruits and vegetables are lost due to poor postharvest handling and pathogen infections in developing countries while it was estimated as 5%-35%in developed countries. Fresh fruits have evolved with a plethora of microorganisms having important roles in maintaining fruit health. However, little information is available on the dynamics, structure, and functional capacities of underpinning fruit microbiomes. The present review discussed environmental conditions favoring fruit-harbored antagonists and their different modes of action for suppressing postharvest pathogens in fruits. It also provides information on omics technologies such as next-generation sequencing (NGS),metaproteomics, metatranscriptomic, and metabolomics studies to characterize fruit microbiomes. With the advent of NGS and meta-omics technologies, microbiome research could bring remarkable development and understanding in succeeding biological treatments. In addition, they may provide us with a fundamental understanding of microclimate requirements for fruit microbiome establishment and microbiome shifts during post-harvest storage, which would be advantageous in developing composite biocontrol treatments for post-harvest decay management.
文摘The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.
文摘The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, cost-effectiveness, and a prolonged shelf life. Controlling the drying process is crucial for ensuring the stability and durability of the product. The traditional approach, which involved mechanical and natural drying, led to decreased productivity and quality. The objective of this research endeavour was to achieve a dry process enhancement while preserving the microbial quality of Trichoderma asperellum (M103). The temperature and relative humidity during the drying period were monitored under two conditions: with and without a dehumidifier. The results demonstrate that the dehumidifier increases drying period efficiency by up to 63%.
