RNA interference(RNAi)has been used for agricultural insect pest control based on silencing of targeted insect genes.However,the effectiveness of RNAi and its applications in insect pest control remain challenging.Her...RNA interference(RNAi)has been used for agricultural insect pest control based on silencing of targeted insect genes.However,the effectiveness of RNAi and its applications in insect pest control remain challenging.Here we review factors that may affect the effectiveness of RNAi application,including the variability in RNAi efficacy among different insect species,a limited understanding of double-stranded RNA(dsRNA)uptake and systemic RNAi mechanisms,and the effective delivery of dsRNA in field conditions.Furthermore,we summarize recent progress in RNAi strategies for crop protection,discuss the advantages and disadvantages of RNAi-based insect control,and propose potential strategies to increase the effectiveness of RNAi in insect control.展开更多
Birds are a huge hazard to agriculture all around the world,causing harm to profitable field crops.Growers use a variety of techniques to keep them away,including visual,auditory,tactile,and olfactory deterrents. This...Birds are a huge hazard to agriculture all around the world,causing harm to profitable field crops.Growers use a variety of techniques to keep them away,including visual,auditory,tactile,and olfactory deterrents. This study presents a comprehensive overview of current bird repellant approaches used in agricultural contexts,as well as potential new ways. The bird repellent techniques include Internet of Things technology,Deep Learning,Convolutional Neural Network,Unmanned Aerial Vehicles,Wireless Sensor Networks and Laser biotechnology. This study’s goal is to find and review about previous approach towards repellent of birds in the crop fields using various technologies.展开更多
The safety of crop protection products and their safe use is of paramount importance and requires that crop protection products are consistently marketed and used worldwide in the required registered quality.To meet t...The safety of crop protection products and their safe use is of paramount importance and requires that crop protection products are consistently marketed and used worldwide in the required registered quality.To meet these high-quality requirements,the highest demands must be placed on the production and purification of technical-grade crop protection products.In this context,impurity profiles are of utmost importance,as unknown impurities at higher than registered concentrations may pose new unknown toxicological risks to users,consumers,and the environment.Particularly high demands are placed on the production and purification of technical grade semisynthetic derivatives of fermentatively derived natural products to meet the required regulatory specifications,to ensure that relevant impurities do not exceed maximum allowable concentrations,to ensure the safe use of such products,and to eliminate any unknown product safety risks.The challenges associated with the manufacture and purification of Afidopyropen and the product safety risks associated with various qualities of technical grade Emamectin benzoate are discussed in detail.展开更多
The increasing of highway engineering construction makes soil and water loss surrounding highway and also influences the growth of crops around, To control soil and water loss, new engineering measures are put forward...The increasing of highway engineering construction makes soil and water loss surrounding highway and also influences the growth of crops around, To control soil and water loss, new engineering measures are put forward to protect soil and water and prevent crops from being damaged.展开更多
Synthetic chemicals have been widely used in modern agriculture as fertilizer,plant growth regulators and pesticides.Although the chemical inputs improved the crop production,it is well known about their negative effe...Synthetic chemicals have been widely used in modern agriculture as fertilizer,plant growth regulators and pesticides.Although the chemical inputs improved the crop production,it is well known about their negative effects,such as environmental residues in water,soil and animals,pest resistance and resurgence and the residues in agricultural produces.The demands for safer food and more friendly environment are now more preferred by humankind in the world.Microbes have already become an alternate for chemical inputs in some aspects in agriculture.The microbes can produce very diverse volatile organic compounds(mVOCs)which play important roles in the interactions between plant and microbes,or among intraspecies or interspecies of microbes.Many mVOCs showed diverse agroactivities,such as insecticidal,bactericidal,fungicidal,herbicidal,plant growth promotion and abiotic stress-tolerance inducing activities.The agroactive mVOCs have diverse structure-types,such as alkane,alkenes,alcohols,aldehydes,ketones,carboxylic acid,esters and lactones,ethers,aromatic ring,terpenes,heterocycles,sulphur-containing VOCs.The promising agroactive properties make it possible to apply mVOCs and their producing microorganisms or synthetic mimics or agroactive mVOCs in crop protection,and so this review focuses on the chemical diversity,agroactivities,and potential application of mVOCs.展开更多
Melatonin(N-Acetyl-5-methoxytryptamine),an endogenously synthesized indoleamine,exerts pleiotropic effects in plant physiology by interacting with other phytohormones,thereby synergistically regulating plant growth,de...Melatonin(N-Acetyl-5-methoxytryptamine),an endogenously synthesized indoleamine,exerts pleiotropic effects in plant physiology by interacting with other phytohormones,thereby synergistically regulating plant growth,development,and stress responses.Recent research has also indicated that melatonin derivatives could be further developed as promising antifungal candidates.Given the significant roles of melatonin,considerable efforts have been devoted to studying its potent functions and underlying mechanisms.This review outlines recent advancements in understanding the roles of melatonin in regulating plant growth and its potential synergistic interactions with pathogens.Additionally,we present our perspectives aimed at elucidating the antifungal mechanisms of melatonin and its derivatives,which could facilitate the development of naturally sourced fungicides and offer innovative strategies for pesticide discovery.展开更多
The effective swath width(ESW)and the droplet penetration rate(DPR)directly affect the spraying quality,the spraying efficiency and the control effect of pests and diseases during the crop protection unmanned aircraft...The effective swath width(ESW)and the droplet penetration rate(DPR)directly affect the spraying quality,the spraying efficiency and the control effect of pests and diseases during the crop protection unmanned aircraft system(CPUAS)application.However,the ESW and DPR are not constant with the changes of the flight speed(FS)and the flight height(FH).In order to investigate the ESW and DPR of the CPUAS P20,four levels of FS(3 m/s,4 m/s,5 m/s and 6 m/s)and three levels of FH(1.5 m,2.0 m and 2.5 m)experiments were carried out according to the first industry standard of China for the CPUAS in the wheat field.The results demonstrated that the ESWs were negatively correlated with the FS and the FH.Most of the ESWs were over 2 m in the 12 treatments,in which the maximum one was 3.25 m(3 m/s,1.5 m).The DPRs were negatively correlated with the FH under the same FS,the average value of the DPRs was 48.37%,in which the maximum one was 78.34%(4 m/s,1.5 m)and the minimum one was 25.5%(6.0 m/s,2.5 m).The statistical analyses showed that the FS had significant impacts on the ESWs(0.01<p-value<0.05)while there were no significant differences among different FH treatments(p-value>0.05).The impacts of both FS and FH on the DPRs were extremely significant(p-value<0.01),and the interactive impacts were significant(0.01<p-value<0.05).Therefore,it is concluded that reducing the FS could increase the ESWs,and reducing the FH could increase the DRPs at the same FS.In conclusion,the maximum spraying efficiency of P20 was 4.342 hm2/h with 6 m/s FS and 1.5 m FH in case of satisfying the requirement of DPRs.This study provided scientific references for guiding the CPUAS spraying.展开更多
In recent years,the crop protection unmanned aerial vehicle(UAV)has been raised great attention around the world due to the advantages of more efficient operation and lower requirement of special landing airport.Howev...In recent years,the crop protection unmanned aerial vehicle(UAV)has been raised great attention around the world due to the advantages of more efficient operation and lower requirement of special landing airport.However,there are few researches on obstacle-avoiding path planning for crop protection UAV.In this study,an improved Dubins curve algorithm was proposed for path planning with multiple obstacle constraints.First,according to the flight parameters of UAV and the types of obstacles in the field,the obstacle circle model and the small obstacle model were established.Second,after selecting the appropriate Dubins curve to generate the obstacle-avoiding path for multiple obstacles,the genetic algorithm(GA)was used to search the optimal obstacle-avoiding path.Third,for turning in the path planning,a strategy considering the size of the spray width and the UAV’s minimum turning radius was presented,which could decrease the speed change times.The results showed that the proposed algorithm can decrease the area of overlap and skip to 205.1%,while the path length increased by only 1.6%in comparison with the traditional Dubins obstacle-avoiding algorithm under the same conditions.With the increase of obstacle radius,the area of overlap and skip reduced effectively with no significant increase in path length.Therefore,the algorithm can efficiently improve the validity of path planning with multiple obstacle constraints and ensure the safety of flight.展开更多
Proper nozzles arrangement is significant to improve spray deposition of crop protection unmanned aerial system(UAS).Besides fuselage structure,the control strategy is another nozzle location changing method when ther...Proper nozzles arrangement is significant to improve spray deposition of crop protection unmanned aerial system(UAS).Besides fuselage structure,the control strategy is another nozzle location changing method when there are multiple sets of nozzles.A four-rotor crop protection UAS equipped with four centrifugal nozzles was used to conduct a field experiment in the rupturing stage of rice.Two sets of nozzles in the front and rear of the fuselage were enabled independently to investigate spray deposition,including spray coverage and droplet density on the sampling cards.Various nozzle rotating speeds and flight speeds were employed in the experiment to study the influence of nozzle location on the deposition.With different nozzle rotating speeds,the droplet spectrum could be controlled.The results show that the average coverage and average cumulative droplet density are negatively correlated with flight speed.Average droplet density is also negatively correlated with the droplet size.Spray deposition of front nozzles is significantly reduced compared with that of the rear nozzles under the same spray parameters,especially when the droplet size is too large or the flight speed is too fast.The reduction is mainly concentrated in the center area of the spray swath.As a result,the average cumulative droplet density of the front nozzles decreases by 25.96%in total.The average droplet density decreases by 18.54%when the droplet size is smaller than 100μm,decreases by 25.02%when between 100μm and 200μm,and decreases by more than half when larger than 200μm.This research can provide guidance for the installation of UAS nozzles and spray control strategy design.展开更多
As a new type of crop protection machine,the crop protection unmanned aerial system(CPUAS)is developing rapidly in China.The wind field generated by the rotor has a great influence on the deposition and penetration of...As a new type of crop protection machine,the crop protection unmanned aerial system(CPUAS)is developing rapidly in China.The wind field generated by the rotor has a great influence on the deposition and penetration of spraying droplets.The purpose of this study was to develop a reliable and stable test platform that could be used for wind field test of CPUAS,and to carry out the downwash experiments on the platform to obtain the downwash distribution law of a CPUAS Z-3N(100 kg level,Nanjing Research Institute on Simulation Technique,Nanjing,China).The tests showed that the performances of the developed platform could meet the expected design requirements.The platform operated stably and reliably during the downwash experiments of Z-3N,which indicated it could be applied for CPUASs of 100 kg level and below.The vibration characteristics of the platform with different heights(2.0 m,3.0 m,5.0 m,7.0 m,10.0 m)were obtained through modal analysis,which could effectively guide avoiding the resonance for stable and reliable operation during the experiments with the tested CPUAS Z-3N.A ring-radial method was designed combined with the platform for the downwash measurement.The experimental results showed that the downwash distribution of Z-3N was not symmetrical;the downwash wind speed decreased with the increase of the radial distance while the changing trend was not consistent as the height increased.Moreover,the area with high wind speed was mainly within 3.0 m of the radial distance,and the maximum value was 11.37 m/s.The study provided a new way for wind field test of CPUASs and would provide some references for better utilization of wind field during the CPUAS spraying.展开更多
The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strateg...The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strategies, which are hampered by the weight and size of inspection equipment, as well as the taxonomic extensiveness of interrupted species. Moreover, some insect pests that impede farmer productivity and profitability are difficult for researchers to address on time due to a lack of appropriate plant protection measures. Farmers’ reliance on synthetic pesticides and biocontrol agents has resulted in major economic and environmental ramifications. DNA barcoding is a novel technology that has the potential to improve Integrated Pest Management decision-making, which is dependent on the ability to correctly identify pest and beneficial organisms. This is due to some natural traits such as phenology or pesticide susceptibility browbeaten by IPM strategies to avert pest establishment. Specifically, Deoxyribonucleic acid (DNA) sequence information was applied effectively for the identification of some micro-organisms. This technology, DNA barcoding, allows for the identification of insect species by using short, standardized gene sequences. DNA barcoding is basically based on repeatable and accessible technique that allows for the mechanisation or automation of species discrimination. This technique bridges the taxonomic bio-security gap and meets the International Plant Protection Convention diagnostic standards for insect identification. This review therefore discusses DNA barcoding as a technique for insect pests’ identification and its potential application for crop protection.展开更多
World crop production requires highly-productive varieties of agricultural crops,which are resistant to pest organisms.Such varieties are also of great importance for the Uzbekistan.Their
Ozone(O_(3))pollution has elevated in China,threatening plants and crop production.Ethylenediurea(EDU)is a chemical alleviating O_(3)-induced phytotoxicities.This study aimed at revealing fluctuating O_(3) exposures e...Ozone(O_(3))pollution has elevated in China,threatening plants and crop production.Ethylenediurea(EDU)is a chemical alleviating O_(3)-induced phytotoxicities.This study aimed at revealing fluctuating O_(3) exposures effects on Youxian No 3(Phaseolus vulgaris)and Sukui No 4(Vigna angularis),two widely grown Chinese bean cultivars,and EDU role in mediating these effects.Plants were periodically treated with EDU(400 mg/L)or water and subjected to charcoal-filtered air(CF)or non-filtered ambient air enriched with an additional targeted O_(3) concentration of 40 ppb(NF40).with subsequent ambient or NF40 exposures.A 10-day exposure to NF40 increased photosynthetic rate(A)while decreasing the leaf intercellular CO_(2) concentration(Ci),but this effect was absent after moving plants to ambient air for two weeks.Moving previously CF-exposed plants to ambient air for two weeks also increased A,which was not linked with Ci but more related to stomatal conductance(gs).Following two one-week and two-week sequential exposures of all plants to NF40,with an intermediate exposure to ambient air,elevated O_(3) reduced chlorophylls(SPAD),A,gs,Ci,and transpiration and decoupled A-gs response.More O_(3) effectswere observed in plants treatedwithNF40 during each O_(3)-treatment cycle,compared to those exposed to CF during the first cycle.The former plants exhibited significantly decreased biomass and water content of leaves and stems but increased flowers biomass and water content.Some of the effects were cultivardependent,with Youxian showing more apparent trade-offs between vegetative growth and reproduction.EDU alleviated various negative O_(3) effects.展开更多
RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied ...RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied in the treatment of human diseases and crop protection against insect pests[2-4].With the availability of the full genome sequences of major mosquito vectors,RNAi has become increasingly used as a novel means of mosquito control[5].展开更多
Crop pests are a permanent threat to horticultural production. Several control methods are recommended for their control, including biological control. This method based on the use of natural enemies is not well estab...Crop pests are a permanent threat to horticultural production. Several control methods are recommended for their control, including biological control. This method based on the use of natural enemies is not well established. The objective of this study was to assess the diversity and abundance of natural enemies of crop pests. A survey of crops associated with pests was carried out on 144 fields in southern Senegal to measure the diversity and abundance of natural enemies of various crop pests, determine the native parasitoid complex and assess parasitism rates. Ecological indices were calculated to assess the diversity of natural enemies. A total of 25 natural enemy species were identified, including 15 parasitoids and 10 predators. Predatory Hemiptera and Parasitoid Hymenoptera were high biodiversity. The parasitism rates vary between 0 and 50% depending on the abundance of pests and parasitoid species. Knowledge of the diversity of natural enemies and the understanding of trophic interactions with pests are important in the development of biological crop protection in order to preserve resilience in agroecosystems.展开更多
Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we ...Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we fine-mapped and characterized a stripe rust resistance gene,YRAYH,on chromosome arm 5BL in the Chinese wheat landrace Anyuehong(AYH).Evaluations of stripe rust response to prevalent Chinese Pst races in near-isogenic lines derived from a cross of Anyuehong and Taichung 29 showed that YrAYH conferred a high level of resistance at all growth stages.Fine mapping using a large segregating population of 9748 plants,narrowed the YRAYH locus to a 3.7 Mb interval on chromosome arm 5BL that included 61 annotated genes.Transcriptome analysis of two NIL pairs identified 64 upregulated differentially expressed genes(DEGs)in the resistant NILs(NILs-R).Annotations indicated that many of these genes have roles in plant disease resistance pathways.Through a combined approach of fine-mapping and transcriptome sequencing,we identified a serine/threonine-protein kinase SRPK as a candidate gene underlying YrAYH.A unique 25 bp insertion was identified in the NILs-R compared to the NILs-S and previously published wheat genomes.An InDel marker was developed and co-segregated with YrAYH.Agronomic trait evaluation of the NILs suggested that YrAYH not only reduces the impact of stripe rust but was also associated with a gene that increases plant height and spike length.展开更多
This review provides a summary of botanicals and plant strengtheners that have potential uses for disease and pest management in potato and tomato cultivation in African.We discuss their possible use to prevent major ...This review provides a summary of botanicals and plant strengtheners that have potential uses for disease and pest management in potato and tomato cultivation in African.We discuss their possible use to prevent major diseases and pests which infest potato and tomato,such as early and late blight,bacterial wilt,potato tuber moth,and tomato leafminer.There are several examples of the successful uses of botanicals for pathogen and pest control relevant for different African climatic conditions;however,most of these studies have been conducted in vitro and often lack field verification.Plant strengtheners(substances that induce and improve crop resistance,yield,and quality)are little studied and used in Africa in comparison to North America and Europe.The possible benefits of using botanicals and plant strengtheners instead of conventional pesticides are discussed here in relation to human health and the environment as well as their modes of action and accessibility to farmers.Lack of knowledge of the composition and active ingredients of extracts,environmental concerns,uncertainties regarding stability and formulation,lack of legislation and limited support from governments,hamper the development of botanicals and plant strengtheners for use in sustainable African agriculture.展开更多
Despite its economic importance of tomato(Solamum lycopersicum L.),many growers are unable to achieve maximum yield of high quality due to insect pest infestation.This study was aimed at determining the effec-tiveness...Despite its economic importance of tomato(Solamum lycopersicum L.),many growers are unable to achieve maximum yield of high quality due to insect pest infestation.This study was aimed at determining the effec-tiveness of parasitoid Eretmocerus eremicus and crude plant extracts of garlic and chilli as an integrated alternative control method of greenhouse whitefly(GHW)on yield of tomato variety“Anna F1”The study was.conducted at Egerton University using a split plot arrangement in ran-domized complete block design,replicated three times.Parasitoid was the main plot factor at two levels(with and without E.eremicus)while sprays of distilled water(negative control),Abamectin(positive control),chilli and garlic extracts formed the sub-plot factors.Data on GHW incidence,population density,parasitisation rate,and yield was collected.Data collected was subjected to analysis of variance and means of significant treatments separated using Tukey's test at p=0.05.Botanical extracts and E.eremicus helped to control whitefly population,infestation,and in en-hancing growth and yield of greenhouse tomato plants compared to where they were not applied.Botanical plant extracts and/or E.eremicus can be used in the management of GHW and to improve tomato yields.展开更多
基金funded by the National Natural Science Foundation of China(32188102 to Lanqin Xia)Natural Science Foundation for Distinguished Young Scholars of Jiangxi province(20212ACB215001 to Xiudao Yu)+1 种基金supported by the China Scholarship Council(202303250062)the GSCAAS-ULg Joint PhD Program。
文摘RNA interference(RNAi)has been used for agricultural insect pest control based on silencing of targeted insect genes.However,the effectiveness of RNAi and its applications in insect pest control remain challenging.Here we review factors that may affect the effectiveness of RNAi application,including the variability in RNAi efficacy among different insect species,a limited understanding of double-stranded RNA(dsRNA)uptake and systemic RNAi mechanisms,and the effective delivery of dsRNA in field conditions.Furthermore,we summarize recent progress in RNAi strategies for crop protection,discuss the advantages and disadvantages of RNAi-based insect control,and propose potential strategies to increase the effectiveness of RNAi in insect control.
文摘Birds are a huge hazard to agriculture all around the world,causing harm to profitable field crops.Growers use a variety of techniques to keep them away,including visual,auditory,tactile,and olfactory deterrents. This study presents a comprehensive overview of current bird repellant approaches used in agricultural contexts,as well as potential new ways. The bird repellent techniques include Internet of Things technology,Deep Learning,Convolutional Neural Network,Unmanned Aerial Vehicles,Wireless Sensor Networks and Laser biotechnology. This study’s goal is to find and review about previous approach towards repellent of birds in the crop fields using various technologies.
文摘The safety of crop protection products and their safe use is of paramount importance and requires that crop protection products are consistently marketed and used worldwide in the required registered quality.To meet these high-quality requirements,the highest demands must be placed on the production and purification of technical-grade crop protection products.In this context,impurity profiles are of utmost importance,as unknown impurities at higher than registered concentrations may pose new unknown toxicological risks to users,consumers,and the environment.Particularly high demands are placed on the production and purification of technical grade semisynthetic derivatives of fermentatively derived natural products to meet the required regulatory specifications,to ensure that relevant impurities do not exceed maximum allowable concentrations,to ensure the safe use of such products,and to eliminate any unknown product safety risks.The challenges associated with the manufacture and purification of Afidopyropen and the product safety risks associated with various qualities of technical grade Emamectin benzoate are discussed in detail.
基金Supported by the Foundation for the Excellent Academic Pacemakers in Harbin City,Heilongjiang Province(2013RFXXJ033)Natural Science Foundation of Heilongjiang Province,China(E201249)
文摘The increasing of highway engineering construction makes soil and water loss surrounding highway and also influences the growth of crops around, To control soil and water loss, new engineering measures are put forward to protect soil and water and prevent crops from being damaged.
基金the Foundation of Hubei Hongshan Labororaty(No.2021hskf016)Hubei Agricultural Science and Technology Innovation Center(2021-620-000-001-027)for financial support for this research.
文摘Synthetic chemicals have been widely used in modern agriculture as fertilizer,plant growth regulators and pesticides.Although the chemical inputs improved the crop production,it is well known about their negative effects,such as environmental residues in water,soil and animals,pest resistance and resurgence and the residues in agricultural produces.The demands for safer food and more friendly environment are now more preferred by humankind in the world.Microbes have already become an alternate for chemical inputs in some aspects in agriculture.The microbes can produce very diverse volatile organic compounds(mVOCs)which play important roles in the interactions between plant and microbes,or among intraspecies or interspecies of microbes.Many mVOCs showed diverse agroactivities,such as insecticidal,bactericidal,fungicidal,herbicidal,plant growth promotion and abiotic stress-tolerance inducing activities.The agroactive mVOCs have diverse structure-types,such as alkane,alkenes,alcohols,aldehydes,ketones,carboxylic acid,esters and lactones,ethers,aromatic ring,terpenes,heterocycles,sulphur-containing VOCs.The promising agroactive properties make it possible to apply mVOCs and their producing microorganisms or synthetic mimics or agroactive mVOCs in crop protection,and so this review focuses on the chemical diversity,agroactivities,and potential application of mVOCs.
基金supported by the National Natural Science Foundation of China(22071072,21801086)the Fundamental Research Funds for the Central Universities of China(2662022LXYJ001)。
文摘Melatonin(N-Acetyl-5-methoxytryptamine),an endogenously synthesized indoleamine,exerts pleiotropic effects in plant physiology by interacting with other phytohormones,thereby synergistically regulating plant growth,development,and stress responses.Recent research has also indicated that melatonin derivatives could be further developed as promising antifungal candidates.Given the significant roles of melatonin,considerable efforts have been devoted to studying its potent functions and underlying mechanisms.This review outlines recent advancements in understanding the roles of melatonin in regulating plant growth and its potential synergistic interactions with pathogens.Additionally,we present our perspectives aimed at elucidating the antifungal mechanisms of melatonin and its derivatives,which could facilitate the development of naturally sourced fungicides and offer innovative strategies for pesticide discovery.
基金This research was supported by the National Key Research and Development Program of China(Grant No.2017YFD0701000)the National Natural Science Foundation of China(No.31701327)+1 种基金Jiangsu Agriculture Science and Technology Innovation Fund(CX(17)1002)Collaborative Innovation Plan of Scientific and Technological Innovation Project(Grant No.CAAS-XTCX2016006).
文摘The effective swath width(ESW)and the droplet penetration rate(DPR)directly affect the spraying quality,the spraying efficiency and the control effect of pests and diseases during the crop protection unmanned aircraft system(CPUAS)application.However,the ESW and DPR are not constant with the changes of the flight speed(FS)and the flight height(FH).In order to investigate the ESW and DPR of the CPUAS P20,four levels of FS(3 m/s,4 m/s,5 m/s and 6 m/s)and three levels of FH(1.5 m,2.0 m and 2.5 m)experiments were carried out according to the first industry standard of China for the CPUAS in the wheat field.The results demonstrated that the ESWs were negatively correlated with the FS and the FH.Most of the ESWs were over 2 m in the 12 treatments,in which the maximum one was 3.25 m(3 m/s,1.5 m).The DPRs were negatively correlated with the FH under the same FS,the average value of the DPRs was 48.37%,in which the maximum one was 78.34%(4 m/s,1.5 m)and the minimum one was 25.5%(6.0 m/s,2.5 m).The statistical analyses showed that the FS had significant impacts on the ESWs(0.01<p-value<0.05)while there were no significant differences among different FH treatments(p-value>0.05).The impacts of both FS and FH on the DPRs were extremely significant(p-value<0.01),and the interactive impacts were significant(0.01<p-value<0.05).Therefore,it is concluded that reducing the FS could increase the ESWs,and reducing the FH could increase the DRPs at the same FS.In conclusion,the maximum spraying efficiency of P20 was 4.342 hm2/h with 6 m/s FS and 1.5 m FH in case of satisfying the requirement of DPRs.This study provided scientific references for guiding the CPUAS spraying.
基金This research was supported by Natural Science Foundation of Heilongjiang Province of China(No.C2018023)China Postdoctoral Science Foundation(No.2015M580254,No.2017T100221)+1 种基金Heilongjiang Postdoctoral Science Foundation(No.LBH-Z15011)The authors would like to thank the anonymous reviewers for their helpful suggestions,which greatly improved the paper.
文摘In recent years,the crop protection unmanned aerial vehicle(UAV)has been raised great attention around the world due to the advantages of more efficient operation and lower requirement of special landing airport.However,there are few researches on obstacle-avoiding path planning for crop protection UAV.In this study,an improved Dubins curve algorithm was proposed for path planning with multiple obstacle constraints.First,according to the flight parameters of UAV and the types of obstacles in the field,the obstacle circle model and the small obstacle model were established.Second,after selecting the appropriate Dubins curve to generate the obstacle-avoiding path for multiple obstacles,the genetic algorithm(GA)was used to search the optimal obstacle-avoiding path.Third,for turning in the path planning,a strategy considering the size of the spray width and the UAV’s minimum turning radius was presented,which could decrease the speed change times.The results showed that the proposed algorithm can decrease the area of overlap and skip to 205.1%,while the path length increased by only 1.6%in comparison with the traditional Dubins obstacle-avoiding algorithm under the same conditions.With the increase of obstacle radius,the area of overlap and skip reduced effectively with no significant increase in path length.Therefore,the algorithm can efficiently improve the validity of path planning with multiple obstacle constraints and ensure the safety of flight.
基金This research was supported by the National Key Research and Development Program of China(Grant No.2017YFD0701000)the Science and Technology Development Plan of Suzhou(Grant No.SNG2020042)+1 种基金China Agriculture Research System of MOF and MARA(Grant No.CARS-12)and the Special Expenses for Basic Scientific Research of Chinese Academy of Agricultural Sciences(Grant No.SR201903).
文摘Proper nozzles arrangement is significant to improve spray deposition of crop protection unmanned aerial system(UAS).Besides fuselage structure,the control strategy is another nozzle location changing method when there are multiple sets of nozzles.A four-rotor crop protection UAS equipped with four centrifugal nozzles was used to conduct a field experiment in the rupturing stage of rice.Two sets of nozzles in the front and rear of the fuselage were enabled independently to investigate spray deposition,including spray coverage and droplet density on the sampling cards.Various nozzle rotating speeds and flight speeds were employed in the experiment to study the influence of nozzle location on the deposition.With different nozzle rotating speeds,the droplet spectrum could be controlled.The results show that the average coverage and average cumulative droplet density are negatively correlated with flight speed.Average droplet density is also negatively correlated with the droplet size.Spray deposition of front nozzles is significantly reduced compared with that of the rear nozzles under the same spray parameters,especially when the droplet size is too large or the flight speed is too fast.The reduction is mainly concentrated in the center area of the spray swath.As a result,the average cumulative droplet density of the front nozzles decreases by 25.96%in total.The average droplet density decreases by 18.54%when the droplet size is smaller than 100μm,decreases by 25.02%when between 100μm and 200μm,and decreases by more than half when larger than 200μm.This research can provide guidance for the installation of UAS nozzles and spray control strategy design.
基金This research was financially supported by the National Key Research and Development Program of China(Grant No.2017YFD0701000)the National Natural Science Foundation of China(Grant No.31701327)+3 种基金the China Agriculture Research System of MOF and MARA(Grant No.CARS-12)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences,Crop Protection Machinery Team(Grant No.CAAS-ASTIP-CPMT)the Jiangsu Science and Technology Development Plan(Grant No.BE2019305)the Science and Technology Development Plan of Suzhou,Jiangsu Province(Grant No.SNG2020042).
文摘As a new type of crop protection machine,the crop protection unmanned aerial system(CPUAS)is developing rapidly in China.The wind field generated by the rotor has a great influence on the deposition and penetration of spraying droplets.The purpose of this study was to develop a reliable and stable test platform that could be used for wind field test of CPUAS,and to carry out the downwash experiments on the platform to obtain the downwash distribution law of a CPUAS Z-3N(100 kg level,Nanjing Research Institute on Simulation Technique,Nanjing,China).The tests showed that the performances of the developed platform could meet the expected design requirements.The platform operated stably and reliably during the downwash experiments of Z-3N,which indicated it could be applied for CPUASs of 100 kg level and below.The vibration characteristics of the platform with different heights(2.0 m,3.0 m,5.0 m,7.0 m,10.0 m)were obtained through modal analysis,which could effectively guide avoiding the resonance for stable and reliable operation during the experiments with the tested CPUAS Z-3N.A ring-radial method was designed combined with the platform for the downwash measurement.The experimental results showed that the downwash distribution of Z-3N was not symmetrical;the downwash wind speed decreased with the increase of the radial distance while the changing trend was not consistent as the height increased.Moreover,the area with high wind speed was mainly within 3.0 m of the radial distance,and the maximum value was 11.37 m/s.The study provided a new way for wind field test of CPUASs and would provide some references for better utilization of wind field during the CPUAS spraying.
文摘The introduction of invasive insect pests across national borders has become a major concern in crop production. Accordingly, national plant protection organizations are challenge to reinforce their monitoring strategies, which are hampered by the weight and size of inspection equipment, as well as the taxonomic extensiveness of interrupted species. Moreover, some insect pests that impede farmer productivity and profitability are difficult for researchers to address on time due to a lack of appropriate plant protection measures. Farmers’ reliance on synthetic pesticides and biocontrol agents has resulted in major economic and environmental ramifications. DNA barcoding is a novel technology that has the potential to improve Integrated Pest Management decision-making, which is dependent on the ability to correctly identify pest and beneficial organisms. This is due to some natural traits such as phenology or pesticide susceptibility browbeaten by IPM strategies to avert pest establishment. Specifically, Deoxyribonucleic acid (DNA) sequence information was applied effectively for the identification of some micro-organisms. This technology, DNA barcoding, allows for the identification of insect species by using short, standardized gene sequences. DNA barcoding is basically based on repeatable and accessible technique that allows for the mechanisation or automation of species discrimination. This technique bridges the taxonomic bio-security gap and meets the International Plant Protection Convention diagnostic standards for insect identification. This review therefore discusses DNA barcoding as a technique for insect pests’ identification and its potential application for crop protection.
文摘World crop production requires highly-productive varieties of agricultural crops,which are resistant to pest organisms.Such varieties are also of great importance for the Uzbekistan.Their
基金supported by the National Natural Science Foundation of China(No.31950410547 and 42107270).
文摘Ozone(O_(3))pollution has elevated in China,threatening plants and crop production.Ethylenediurea(EDU)is a chemical alleviating O_(3)-induced phytotoxicities.This study aimed at revealing fluctuating O_(3) exposures effects on Youxian No 3(Phaseolus vulgaris)and Sukui No 4(Vigna angularis),two widely grown Chinese bean cultivars,and EDU role in mediating these effects.Plants were periodically treated with EDU(400 mg/L)or water and subjected to charcoal-filtered air(CF)or non-filtered ambient air enriched with an additional targeted O_(3) concentration of 40 ppb(NF40).with subsequent ambient or NF40 exposures.A 10-day exposure to NF40 increased photosynthetic rate(A)while decreasing the leaf intercellular CO_(2) concentration(Ci),but this effect was absent after moving plants to ambient air for two weeks.Moving previously CF-exposed plants to ambient air for two weeks also increased A,which was not linked with Ci but more related to stomatal conductance(gs).Following two one-week and two-week sequential exposures of all plants to NF40,with an intermediate exposure to ambient air,elevated O_(3) reduced chlorophylls(SPAD),A,gs,Ci,and transpiration and decoupled A-gs response.More O_(3) effectswere observed in plants treatedwithNF40 during each O_(3)-treatment cycle,compared to those exposed to CF during the first cycle.The former plants exhibited significantly decreased biomass and water content of leaves and stems but increased flowers biomass and water content.Some of the effects were cultivardependent,with Youxian showing more apparent trade-offs between vegetative growth and reproduction.EDU alleviated various negative O_(3) effects.
基金supported by grants from the National Key Research and Development Program(2023YFE0113600).
文摘RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied in the treatment of human diseases and crop protection against insect pests[2-4].With the availability of the full genome sequences of major mosquito vectors,RNAi has become increasingly used as a novel means of mosquito control[5].
文摘Crop pests are a permanent threat to horticultural production. Several control methods are recommended for their control, including biological control. This method based on the use of natural enemies is not well established. The objective of this study was to assess the diversity and abundance of natural enemies of crop pests. A survey of crops associated with pests was carried out on 144 fields in southern Senegal to measure the diversity and abundance of natural enemies of various crop pests, determine the native parasitoid complex and assess parasitism rates. Ecological indices were calculated to assess the diversity of natural enemies. A total of 25 natural enemy species were identified, including 15 parasitoids and 10 predators. Predatory Hemiptera and Parasitoid Hymenoptera were high biodiversity. The parasitism rates vary between 0 and 50% depending on the abundance of pests and parasitoid species. Knowledge of the diversity of natural enemies and the understanding of trophic interactions with pests are important in the development of biological crop protection in order to preserve resilience in agroecosystems.
基金supported by grants from the Major Program of National Agricultural Science and Technology of China(NK20220607)the National Natural Science Foundation of China(32272059 and 31971883)the Science and Technology Department of Sichuan Province(2021YFYZ0002,2022ZDZX0014,and 2023NSFSC1995)。
文摘Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we fine-mapped and characterized a stripe rust resistance gene,YRAYH,on chromosome arm 5BL in the Chinese wheat landrace Anyuehong(AYH).Evaluations of stripe rust response to prevalent Chinese Pst races in near-isogenic lines derived from a cross of Anyuehong and Taichung 29 showed that YrAYH conferred a high level of resistance at all growth stages.Fine mapping using a large segregating population of 9748 plants,narrowed the YRAYH locus to a 3.7 Mb interval on chromosome arm 5BL that included 61 annotated genes.Transcriptome analysis of two NIL pairs identified 64 upregulated differentially expressed genes(DEGs)in the resistant NILs(NILs-R).Annotations indicated that many of these genes have roles in plant disease resistance pathways.Through a combined approach of fine-mapping and transcriptome sequencing,we identified a serine/threonine-protein kinase SRPK as a candidate gene underlying YrAYH.A unique 25 bp insertion was identified in the NILs-R compared to the NILs-S and previously published wheat genomes.An InDel marker was developed and co-segregated with YrAYH.Agronomic trait evaluation of the NILs suggested that YrAYH not only reduces the impact of stripe rust but was also associated with a gene that increases plant height and spike length.
基金the AgriFose2030 programmethe swedish International Development Cooperation Agency (SIDA)the Swedish Foundation for International Cooperation in Research and Higher Education (STINT) for financial support
文摘This review provides a summary of botanicals and plant strengtheners that have potential uses for disease and pest management in potato and tomato cultivation in African.We discuss their possible use to prevent major diseases and pests which infest potato and tomato,such as early and late blight,bacterial wilt,potato tuber moth,and tomato leafminer.There are several examples of the successful uses of botanicals for pathogen and pest control relevant for different African climatic conditions;however,most of these studies have been conducted in vitro and often lack field verification.Plant strengtheners(substances that induce and improve crop resistance,yield,and quality)are little studied and used in Africa in comparison to North America and Europe.The possible benefits of using botanicals and plant strengtheners instead of conventional pesticides are discussed here in relation to human health and the environment as well as their modes of action and accessibility to farmers.Lack of knowledge of the composition and active ingredients of extracts,environmental concerns,uncertainties regarding stability and formulation,lack of legislation and limited support from governments,hamper the development of botanicals and plant strengtheners for use in sustainable African agriculture.
文摘Despite its economic importance of tomato(Solamum lycopersicum L.),many growers are unable to achieve maximum yield of high quality due to insect pest infestation.This study was aimed at determining the effec-tiveness of parasitoid Eretmocerus eremicus and crude plant extracts of garlic and chilli as an integrated alternative control method of greenhouse whitefly(GHW)on yield of tomato variety“Anna F1”The study was.conducted at Egerton University using a split plot arrangement in ran-domized complete block design,replicated three times.Parasitoid was the main plot factor at two levels(with and without E.eremicus)while sprays of distilled water(negative control),Abamectin(positive control),chilli and garlic extracts formed the sub-plot factors.Data on GHW incidence,population density,parasitisation rate,and yield was collected.Data collected was subjected to analysis of variance and means of significant treatments separated using Tukey's test at p=0.05.Botanical extracts and E.eremicus helped to control whitefly population,infestation,and in en-hancing growth and yield of greenhouse tomato plants compared to where they were not applied.Botanical plant extracts and/or E.eremicus can be used in the management of GHW and to improve tomato yields.
