The situation of occurrence and hazards by Tetranychus truncatus and T. urticae on corns in test garden of Agricultural College of Yanbian University were narrated in detail. The characteristics of distribution and da...The situation of occurrence and hazards by Tetranychus truncatus and T. urticae on corns in test garden of Agricultural College of Yanbian University were narrated in detail. The characteristics of distribution and damage by T. truncates and T. urticae, morphological characteristics, the rule of currencies and its relation- ship with environment were summarized, and the methods of comprehensive treat- ment were put out, which could effectively control the hazard degree of T. truncates and T. urticae on corns.展开更多
Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphat...Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; andC-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, andtheir application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zeamays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Underco-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for bothdent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were highin experiment 1, but were very low in experiment 2, because the environmental conditions were different in the twoexperiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrientconcentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease inexperiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between co-situs and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot androot weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially atthe fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situsapplication and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation wasreversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cmdepth).展开更多
In order to study mechanical behaviors of corn stalk powder during the compaction, the yield criterion for corn stalk powder is proposed with a plasticity theory. From the stress-strain curves of uni-axial compaction ...In order to study mechanical behaviors of corn stalk powder during the compaction, the yield criterion for corn stalk powder is proposed with a plasticity theory. From the stress-strain curves of uni-axial compaction test for corn stalk powder, the constitutive model, in which the equations are modified by experiments on corn stalk powder, is adopted to describe plastic behaviors of powder, and is discussed based on the incremental theory and deformation theory. The numerical results agree well with the experimental ones.展开更多
Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin f...Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.展开更多
Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(P...Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(Pi)in soil through their roots.Pi,which is usually sequestered in soils,is not easily absorbed by plants and represses plant growth.Plants have developed a series of mechanisms to cope with P deficiency.Moreover,P fertilizer applications are critical for maximizing crop yield.Maize is a major cereal crop cultivated worldwide.Increasing its P-use efficiency is important for optimizing maize production.Over the past two decades,considerable progresses have been achieved in studies aimed at adapting maize varieties to changes in environmental P supply.Here,we present an overview of the morphological,physiological,and molecular mechanisms involved in P acquisition,translocation,and redistribution in maize and combine the advances in Arabidopsis and rice,to better elucidate the progress of P nutrition.Additionally,we summarize the correlation between P and abiotic stress responses.Clarifying the mechanisms relevant to improving P absorption and use in maize can guide future research on sustainable agriculture.展开更多
A flower-like BiOBr photocatalyst(CS/BiOBr)was prepared by using the carbon material derived from corn straw(CS)as the carrier.The prepared composites were characterized by X-ray diffraction(XRD),Fourier transform inf...A flower-like BiOBr photocatalyst(CS/BiOBr)was prepared by using the carbon material derived from corn straw(CS)as the carrier.The prepared composites were characterized by X-ray diffraction(XRD),Fourier transform infrared(FIIR)spectra,scanning electron microscope(SEM),X-ray photoelectron spectra(XPS),and UV-Vis diffuse reflectance spectra(UV-Vis DRS).The SEM analyses indicate that the introduction of CS promotes the formation of a unique flower-like structure in BiOBr,which not only optimizes the efficiency of light capture but also increases the specific surface area of BiOBr.The bandgap of the composite was narrower compared with the pure BiOBr.The CS/BiOBr composites exhibited higher photocatalytic activity than pure CS and BiOBr under visible light irradiation,and a higher first-order reaction rate constant(k)of 0.0437 min-1 than BiOBr(0.0146 min^(-1)),and exhibited excellent stability and reusability during the cyclic run.The enhanced photocatalytic activity is attributed to the efficient separation of photoinduced electrons and holes.Superoxide radicals and holes were the major active species.展开更多
Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiv...Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiveness,and environ-mental friendliness.The pyrolysis method affects the microstructure of the material,and ultimately its so-dium storage performance.Our previous work has shown that pyrolysis in a sealed graphite vessel im-proved the sodium storage performance of the car-bon,however the changes in its microstructure and the way this influences the sodium storage are still unclear.A series of hard carbon materials derived from corncobs(CCG-T,where T is the pyrolysis temperature)were pyrolyzed in a sealed graphite vessel at different temperatures.As the pyrolysis temperature increased from 1000 to 1400℃ small carbon domains gradually transformed into long and curved domains.At the same time,a greater number of large open pores with uniform apertures,as well as more closed pores,were formed.With the further increase of pyrolysis temperature to 1600℃,the long and curved domains became longer and straighter,and some closed pores gradually became open.CCG-1400,with abundant closed pores,had a superior SIB performance,with an initial reversible ca-pacity of 320.73 mAh g^(-1) at a current density of 30 mA g^(-1),an initial Coulomb efficiency(ICE)of 84.34%,and a capacity re-tention of 96.70%after 100 cycles.This study provides a method for the precise regulation of the microcrystalline and pore structures of hard carbon materials.展开更多
[Objectives]To address the weeding challenges within the corn and soybean strip intercropping field and identify appropriate herbicide types and application methods suitable for the corn and soybean strip intercroppin...[Objectives]To address the weeding challenges within the corn and soybean strip intercropping field and identify appropriate herbicide types and application methods suitable for the corn and soybean strip intercropping fields in Siyang County.[Methods]The trial comprised six herbicide treatments and one blank control,with investigations conducted to assess efficacy,safety,and yield.[Results]Each herbicide treatment effectively controlled weeds,demonstrated high safety,and enhanced the yields of both soybeans and corn.The combined application of soil sealing with stem and leaf spray exhibited superior overall weed control compared to soil sealing alone.At 28 d following stem and leaf spray,the plant control effect and fresh weight control effect against weeds in the combined treatment of soil sealing with stem and leaf spray all exceeded 89%.[Conclusions]This study offers technical support for advancing the practice of strip intercropping between corn and soybeans.展开更多
Fermented corn starch has emerged as a promising functional food due to its triad of gut biotics,prebiotic,probiotic,and postbiotic properties,which present significant potential for the management of type 2 diabetes ...Fermented corn starch has emerged as a promising functional food due to its triad of gut biotics,prebiotic,probiotic,and postbiotic properties,which present significant potential for the management of type 2 diabetes through gut microbiota modulation.During fermentation,microbial activity alters the starch matrix,enhancing the production of bioactive compounds such as resistant starch,isomalto-oligosaccharides,and resistant dextrin,which improve insulin sensitivity,reduce inflammation,and support glycemic control.Additionally,fermented corn starch harbors beneficial microbial strains including Lactiplantibacillus fermentum,Bifidobacterium breve,and Saccharomyces cerevisiae,which reinforce gut barrier integrity,stimulate incretin secretion,and suppress systemic inflammation.Postbiotic metabolites such as short-chain fatty acids,exopolysaccharides,and bacteriocins further contribute to glucose homeostasis through immune modulation and gut hormone regulation.Despite its promise,the clinical translation of fermented corn starch is limited by safety concerns(e.g.,contamination with pathogens or mycotoxins),lack of standardized fermentation protocols,and a scarcity of targeted studies.This review synthesizes current evidence on the antidiabetic potential of fermented corn starch,advocating for its integration into precision nutrition approaches and supporting further research to address safety and standardization challenges in functional food development.展开更多
A field experiment was conducted to investigate the effect of integrated nano-fertilizer spray and vermicompost in growth and quality of corn yield in calcareous soil at College ofAgricultural Engineering Sciences/Uni...A field experiment was conducted to investigate the effect of integrated nano-fertilizer spray and vermicompost in growth and quality of corn yield in calcareous soil at College ofAgricultural Engineering Sciences/University of Baghdad/Iraq during the autumn season of 2022 using Split Split Plot Design in a randomized complete block design with three replicates.Main plots were designated to two types of vermicompost(local and imported).The secondary plots were assigned to vermicompost added to the soil at three levels of 0,10 and 20 Mg ha-1.The third plots were assigned to nano-fertilizer containing N,P,K,Zn,Fe and Mn at 0,50,100 and 150 mg L-1 sprayed on plant at 20,40 and 60 days after planting.The results showed a significant effect of local vermicompost achieving available nitrogen and phosphorus in the soil as 43.31 mg N kg-1 soil and 19.25 mg P kg-1 soil.In the leaves,nitrogen was 3.86%,potassium 4.54%,iron 174.22 mg Fe kg-1 and Zinc was 73.53 mg Zn kg-1,grain yield was 165.48 Mg ha-1.Adding vermicompost to the soil at 20 Mg ha-1 achieving in available nitrogen in the soil of 43.74 mg N kg-1 soil,available phosphorus of 19.72 mg P kg-1 soil and available potassium of 196.93 mg K kg-1 soil.In the leaves,nitrogen was 4.37%,phosphorus was 0.44%,potassium 4.87%,iron was 182.63 mg Fe kg-1,zinc was 73.70 mg Zn kg-1 and grain yield was 168.43 Mg ha-1.Spraying nano-fertilizer on the plant at 150 mg L-1 achieved In the leaves,nitrogen 4.28%,phosphorus of 0.46%,potassium of 5.10%,iron of 204.83 mg Fe kg-1,zinc of 89.28 mg Zn kg-1 and manganese of 234.07 mg Mn kg-1 and grain yield was 172.88 Mg ha-1.展开更多
The soybean and corn strip compound planting technology is a crucial measure for improving land use efficiency and ensuring food security.This paper deeply analyzed the principles,advantages,and key technical aspects ...The soybean and corn strip compound planting technology is a crucial measure for improving land use efficiency and ensuring food security.This paper deeply analyzed the principles,advantages,and key technical aspects of this technology,including variety selection,planting pattern,sowing management,and field management.It also illustrated its application effectiveness through practical cases and proposed corresponding solutions to existing challenges in its promotion.This study provides theoretical support and practical reference for the widespread adoption and efficient application of this technology.展开更多
Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism ...Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin synthesis.However,we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val,Trp,and(or)Ile.Methods Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with 4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were formulated.Seven additional diets were formu-lated by fortifying the basal diet with 20%CFP with Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-phase feeding program was used,with d 1 to 14 being phase 1 and d 15 to 28 being phase 2.Fecal scores were recorded every other day.Blood samples were collected on d 14 and 28 from one pig per pen.On d 14,fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial protein.These pigs were also euthanized and ileal tissue was collected.Results There were no effects of dietary treatments on any of the parameters evaluated in phase 1.Inclusion of 10%or 20%CFP in diets reduced(P<0.05)final body weight on d 28,and average daily gain(ADG)and average daily feed intake(ADFI)in phase 2 and for the entire experimental period.However,pigs fed the CFP diet supplemented with Val,Ile,and Trp had final body weight,ADFI,ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control diet.Fecal scores in phase 2 were reduced(P<0.05)if CFP was used.Conclusions Corn fermented protein may be included by up to 20%in diets for weanling pigs without affecting growth performance,gut health,or hindgut fermentation,if diets are fortified with extra Val,Trp,and Ile.Inclusion of CFP also improved fecal consistency of pigs.展开更多
The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National ...The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence.展开更多
Enzymatic modification is an important approach to changing the structure and expanding industrial application of natural starch. In the process of starch modification, thermostable enzymes are favored owing to their ...Enzymatic modification is an important approach to changing the structure and expanding industrial application of natural starch. In the process of starch modification, thermostable enzymes are favored owing to their compatibility with higher reaction temperatures and lower required dosage. In this study, thermostable glucoamylase from Thermothelomyces thermophilus(TtGA) was heterologously expressed in Pichia pastoris, and its effects on the structure and physicochemical properties of raw corn starch were determined. The purified TtGA had a molecular weight of approximately 66 kDa, and its optimum reaction temperature and pH were 50 ℃ and 5.0, respectively. TtGA retained > 60% of its activity following treatment at 60 ℃ for 2 h and remained stable within a pH range of 4.0–7.0 for 6 h. The enzymatic modification of raw corn starch with TtGA led to 3% hydrolysis at 50 ℃ for 24 h. In comparison with natural raw corn starch, TtGA-modified starch had a smaller particle size with an unchanged crystalline structure, increased relative crystallinity, and amylose content.Scanning electronic observation showed that larger pores were formed on the surface of starch particles, and Fourier-transform infrared spectroscopy indicated that TtGA increased the degree of order in the raw corn starch.TtGA modification caused enhanced viscosity of the raw corn starch and altered the rheological properties with decreases in storage and loss moduli, as well as shear viscosity. Moreover, TtGA treatment enhanced the thermal characteristics of the raw corn starch, and decreased gelatinization enthalpy. This study provides detailed evidence for TtGA modification of raw corn starch, which would be helpful for its practical utilization in starch modification.展开更多
Southern corn rust(SCR)is an airborne fungal disease caused by Puccinia polysora Underw.(P.polysora)that adversely impacts maize quality and yields worldwide.Screening for new elite SCR-resistant maize loci or genes h...Southern corn rust(SCR)is an airborne fungal disease caused by Puccinia polysora Underw.(P.polysora)that adversely impacts maize quality and yields worldwide.Screening for new elite SCR-resistant maize loci or genes has the potential to enhance overall resistance to this pathogen.Using phenotypic SCR resistance-related data collected over two years and three geographical environments,a genome-wide association study was carried out in this work,which eventually identified 91 loci that were substantially correlated with SCR susceptibility.These included 13 loci that were significant in at least three environments and overlapped with 74 candidate genes(B73_RefGen_v4).Comparative transcriptomic analyses were then performed to identify the genes related to SCR infection,with 2,586 and 797 differentially expressed genes(DEGs)ultimately being identified in the resistant Qi319and susceptible 8112 inbred lines following P.polysora infection,respectively,including 306 genes common to both lines.Subsequent integrative multi-omics investigations identified four potential candidate SCR response-related genes.One of these genes is ZmHCT9,which encodes the protein hydroxycinnamoyl transferase 9.This gene was up-regulated in susceptible inbred lines and linked to greater P.polysora resistance as confirmed through cucumber mosaic virus(CMV)-based virus induced-gene silencing(VIGS)system-mediated gene silencing.These data provide important insights into the genetic basis of the maize SCR response.They will be useful for for future research on potential genes related to SCR resistance in maize.展开更多
The objective of this study was to characterize the rumination time in lactating dairy cows fed with corn silage.Rumination time was recorded 24 h/day using direct visual observation.Six trials were conducted during 2...The objective of this study was to characterize the rumination time in lactating dairy cows fed with corn silage.Rumination time was recorded 24 h/day using direct visual observation.Six trials were conducted during 2018,2019 and 2020,and rumination time was recorded in 480-2-hour periods from 40 Holstein Friesian cows.In each trial,6 or 8 cows were selected and balanced for days in milk(DIM),milk production and number of lactations.Each cow was recorded continuously for periods of 2 h at a time to complete a full 24-h period per week(12 values per day).Data from all cows were associated with 4 reproductive statuses of cows:Inseminated(1-45 days after insemination),Open(45-150 days after calving),not-pregnant and pregnant.The longest rumination time(RT)was found in pregnant cows(average 536.9±29.87 min/day),and the shortest RT was in open cows(average 420.3±63.2 min/day).Inseminated and non-pregnant cows were found with intermediate values(527.3±82.4 min/day and 467.1±30.7 respectively).Significantly different RT means were found between pregnant and open cows(p<0.0001),pregnant vs.inseminated cows(p<0.0001),and between inseminated and open cows(p=0.0005).We concluded that some gynecological conditions of lactating cows affect the RT.Measurement of RT by visual observations proved to be acceptable for the conditions of this study when cows were housed indoors and were fed with partial mixed ration(PMR)based on corn silage.展开更多
Agricultural production(especially intensive rice production)is a primary income source for over 2.0×10^(7) people in the Vietnamese Mekong River Delta.However,adverse climate change impacts,socio-economic change...Agricultural production(especially intensive rice production)is a primary income source for over 2.0×10^(7) people in the Vietnamese Mekong River Delta.However,adverse climate change impacts,socio-economic change,and high dependence on farm inputs for intensive production constrain the longer-term sustainability of rice systems.Government and agribusiness actors are encouraging more farmers to grow non-rice crops and supporting the upscaling of alternative crops to paddy rice.We used a qualitative approach to investigate the value chain characteristics,as well as constraints and opportunities of alternative crops via two case studies(baby corn and honeydew melon)in An Giang and Hau Giang provinces,Vietnam.Data collection involved focus group discussions with local farmers and interviews with farmers and industry experts.Thematic analysis was used to compile the findings,and the results were validated with local government staff.The baby corn value chain featured on-going and stable market demand(including value-addition)and better vertical coordination(e.g.,written contracts and financial support).The honeydew melon value chain featured positive relationships between farmers and traders despite less-developed vertical coordination.There are opportunities for value chain engagement through product quality certification,value-addition,and accessing high-value domestic and export markets.However,farmers require crop-specific and generic support from private and public sectors.Increased labour requirements and limited access to finance and credit limit value chain participation.Upscaling and marketing alternative crops can enhance farmer profitability and support non-farming agricultural business establishment,economic growth,and community development.Efficient value chains will be critical to ensure the adoption of alternative crops and development of crop-specific agribusiness models.These findings can inform policy-makers and change facilitators in designing targeted interventions to support the adoption of alternative crops in the study area as well as in Vietnam and globally.展开更多
The widely consumed high-fructose corn syrup(HFCS) has been linked to neurological disorders. In a recent article published in Nature, Wang et al. extend the harms of excessive fructose intake on neurodevelopment to t...The widely consumed high-fructose corn syrup(HFCS) has been linked to neurological disorders. In a recent article published in Nature, Wang et al. extend the harms of excessive fructose intake on neurodevelopment to the prenatal and lactation stages. They reveal that fructose uptake via GLUT5 reprograms microglial metabolism towards a low-ATP production state, suppressing microglial phagocytosis and impairing neurodevelopment.展开更多
This study examines the development of loose-fill thermal insulation materials derived from annual plant residues,such as wheat straw,water reeds,and corn stalks,processed using the chemimechanical pulping(CMP)techniq...This study examines the development of loose-fill thermal insulation materials derived from annual plant residues,such as wheat straw,water reeds,and corn stalks,processed using the chemimechanical pulping(CMP)technique.The chopped plants were soda-cooked for 30 min,varying NaOH concentration(2%–8%on a dry basis of biomass),and mechanically refined using different disc types.The CMPprocess enhances the homogeneity and stability of defibratedmaterial,yielding improved insulation properties compared to untreated chopped rawmaterials.Chemical analysis revealed that CMP increases cellulose content and reduces lignin levels,enhancing water retention and vapor diffusion properties.Settlement tests confirmed that CMP materials are more resistant to compaction under vibration,maintaining long-term performance.Additionally,the CMP enables the production of lightweight materials that require less resource consumption while achieving comparable thermal insulation performance.The investigated biobased materials offer a sustainable alternative to conventional insulation,with competing thermal conductivity values(0.041-0.046 W/mK)at the settlement-resistant bulk density level of 60 kg/m^(3).The thermal conductivity of CMP materials remains minimally affected.However,the resulting fibers demonstrate significant advantages in stability and material efficiency.This highlights its suitability for loose-fill applications to improve the sustainability of the construction.Using renewable plant residues,CMP-based insulation materials align with circular economy principles and contribute to environmental sustainability.This research underscores the potential of CMP materials to reduce greenhouse gas emissions,optimize resource use,and promote eco-friendly building practices.展开更多
Currently,unmanned aerial vehicles(UAVs)were widely applied to spray for pest and disease control.However,spray effect can be further improved by setting operation parameters more reasonably and scientifically.Therefo...Currently,unmanned aerial vehicles(UAVs)were widely applied to spray for pest and disease control.However,spray effect can be further improved by setting operation parameters more reasonably and scientifically.Therefore,this study attempts to derive the relationship between operation parameters and spray effect.Different growth stages were distinguished by various corn heights.A six-rotor UAV was operated at different heights and velocities to test pesticides spray effects for corns at different growth stages.Different plant canopy coverage rate and penetrating coefficients were obtained,according to which,the effects on droplet deposition rate caused by different UAVs’operation parameters were analyzed.Droplet penetrating coefficients were applied as indexes to evaluate and select UAVs operation parameters for corns at different growth stages respectively.Mathematical models of droplet penetrating coefficients with UAVs operation parameters were established for corns at all growth stages.The determination coefficients(R2)of all models were greater than 0.90 and average relative errors were within 20%,which asserted high forecasting accuracy of droplet penetrating rate.With the help of the models,parameters like operating height away from the bottom of corns and UAVs velocities were further analyzed,which guided the optimization of parameter settings and selection of spray methods for corns at different growth stages.展开更多
文摘The situation of occurrence and hazards by Tetranychus truncatus and T. urticae on corns in test garden of Agricultural College of Yanbian University were narrated in detail. The characteristics of distribution and damage by T. truncates and T. urticae, morphological characteristics, the rule of currencies and its relation- ship with environment were summarized, and the methods of comprehensive treat- ment were put out, which could effectively control the hazard degree of T. truncates and T. urticae on corns.
基金partly supported by the National Natural Science Foundation of China(NFSC)(30230230 and 30070429)
文摘Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; andC-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, andtheir application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zeamays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Underco-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for bothdent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were highin experiment 1, but were very low in experiment 2, because the environmental conditions were different in the twoexperiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrientconcentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease inexperiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between co-situs and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot androot weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially atthe fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situsapplication and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation wasreversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cmdepth).
基金Supported by the Fork Ying Tong Education Foundation (Grant No. 81029)
文摘In order to study mechanical behaviors of corn stalk powder during the compaction, the yield criterion for corn stalk powder is proposed with a plasticity theory. From the stress-strain curves of uni-axial compaction test for corn stalk powder, the constitutive model, in which the equations are modified by experiments on corn stalk powder, is adopted to describe plastic behaviors of powder, and is discussed based on the incremental theory and deformation theory. The numerical results agree well with the experimental ones.
基金supported by the Fundamental Research Funds for the Central Universities(QNTD202302)National Natural Science Foundation of China(22378024)the Foreign expert program(G2022109001L).
文摘Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.
基金supported by grants from the National Key Research and Development Program of China(2021YFF1000500)the National Natural Science Foundation of China(32370272,31970273,and 31921001).
文摘Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(Pi)in soil through their roots.Pi,which is usually sequestered in soils,is not easily absorbed by plants and represses plant growth.Plants have developed a series of mechanisms to cope with P deficiency.Moreover,P fertilizer applications are critical for maximizing crop yield.Maize is a major cereal crop cultivated worldwide.Increasing its P-use efficiency is important for optimizing maize production.Over the past two decades,considerable progresses have been achieved in studies aimed at adapting maize varieties to changes in environmental P supply.Here,we present an overview of the morphological,physiological,and molecular mechanisms involved in P acquisition,translocation,and redistribution in maize and combine the advances in Arabidopsis and rice,to better elucidate the progress of P nutrition.Additionally,we summarize the correlation between P and abiotic stress responses.Clarifying the mechanisms relevant to improving P absorption and use in maize can guide future research on sustainable agriculture.
文摘A flower-like BiOBr photocatalyst(CS/BiOBr)was prepared by using the carbon material derived from corn straw(CS)as the carrier.The prepared composites were characterized by X-ray diffraction(XRD),Fourier transform infrared(FIIR)spectra,scanning electron microscope(SEM),X-ray photoelectron spectra(XPS),and UV-Vis diffuse reflectance spectra(UV-Vis DRS).The SEM analyses indicate that the introduction of CS promotes the formation of a unique flower-like structure in BiOBr,which not only optimizes the efficiency of light capture but also increases the specific surface area of BiOBr.The bandgap of the composite was narrower compared with the pure BiOBr.The CS/BiOBr composites exhibited higher photocatalytic activity than pure CS and BiOBr under visible light irradiation,and a higher first-order reaction rate constant(k)of 0.0437 min-1 than BiOBr(0.0146 min^(-1)),and exhibited excellent stability and reusability during the cyclic run.The enhanced photocatalytic activity is attributed to the efficient separation of photoinduced electrons and holes.Superoxide radicals and holes were the major active species.
文摘Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiveness,and environ-mental friendliness.The pyrolysis method affects the microstructure of the material,and ultimately its so-dium storage performance.Our previous work has shown that pyrolysis in a sealed graphite vessel im-proved the sodium storage performance of the car-bon,however the changes in its microstructure and the way this influences the sodium storage are still unclear.A series of hard carbon materials derived from corncobs(CCG-T,where T is the pyrolysis temperature)were pyrolyzed in a sealed graphite vessel at different temperatures.As the pyrolysis temperature increased from 1000 to 1400℃ small carbon domains gradually transformed into long and curved domains.At the same time,a greater number of large open pores with uniform apertures,as well as more closed pores,were formed.With the further increase of pyrolysis temperature to 1600℃,the long and curved domains became longer and straighter,and some closed pores gradually became open.CCG-1400,with abundant closed pores,had a superior SIB performance,with an initial reversible ca-pacity of 320.73 mAh g^(-1) at a current density of 30 mA g^(-1),an initial Coulomb efficiency(ICE)of 84.34%,and a capacity re-tention of 96.70%after 100 cycles.This study provides a method for the precise regulation of the microcrystalline and pore structures of hard carbon materials.
文摘[Objectives]To address the weeding challenges within the corn and soybean strip intercropping field and identify appropriate herbicide types and application methods suitable for the corn and soybean strip intercropping fields in Siyang County.[Methods]The trial comprised six herbicide treatments and one blank control,with investigations conducted to assess efficacy,safety,and yield.[Results]Each herbicide treatment effectively controlled weeds,demonstrated high safety,and enhanced the yields of both soybeans and corn.The combined application of soil sealing with stem and leaf spray exhibited superior overall weed control compared to soil sealing alone.At 28 d following stem and leaf spray,the plant control effect and fresh weight control effect against weeds in the combined treatment of soil sealing with stem and leaf spray all exceeded 89%.[Conclusions]This study offers technical support for advancing the practice of strip intercropping between corn and soybeans.
基金Supported by the Research Office,University of KwaZulu-Natal,Durbanan Incentive Grant from the National Research Foundation,Pretoria,South Africa,No.145943.
文摘Fermented corn starch has emerged as a promising functional food due to its triad of gut biotics,prebiotic,probiotic,and postbiotic properties,which present significant potential for the management of type 2 diabetes through gut microbiota modulation.During fermentation,microbial activity alters the starch matrix,enhancing the production of bioactive compounds such as resistant starch,isomalto-oligosaccharides,and resistant dextrin,which improve insulin sensitivity,reduce inflammation,and support glycemic control.Additionally,fermented corn starch harbors beneficial microbial strains including Lactiplantibacillus fermentum,Bifidobacterium breve,and Saccharomyces cerevisiae,which reinforce gut barrier integrity,stimulate incretin secretion,and suppress systemic inflammation.Postbiotic metabolites such as short-chain fatty acids,exopolysaccharides,and bacteriocins further contribute to glucose homeostasis through immune modulation and gut hormone regulation.Despite its promise,the clinical translation of fermented corn starch is limited by safety concerns(e.g.,contamination with pathogens or mycotoxins),lack of standardized fermentation protocols,and a scarcity of targeted studies.This review synthesizes current evidence on the antidiabetic potential of fermented corn starch,advocating for its integration into precision nutrition approaches and supporting further research to address safety and standardization challenges in functional food development.
文摘A field experiment was conducted to investigate the effect of integrated nano-fertilizer spray and vermicompost in growth and quality of corn yield in calcareous soil at College ofAgricultural Engineering Sciences/University of Baghdad/Iraq during the autumn season of 2022 using Split Split Plot Design in a randomized complete block design with three replicates.Main plots were designated to two types of vermicompost(local and imported).The secondary plots were assigned to vermicompost added to the soil at three levels of 0,10 and 20 Mg ha-1.The third plots were assigned to nano-fertilizer containing N,P,K,Zn,Fe and Mn at 0,50,100 and 150 mg L-1 sprayed on plant at 20,40 and 60 days after planting.The results showed a significant effect of local vermicompost achieving available nitrogen and phosphorus in the soil as 43.31 mg N kg-1 soil and 19.25 mg P kg-1 soil.In the leaves,nitrogen was 3.86%,potassium 4.54%,iron 174.22 mg Fe kg-1 and Zinc was 73.53 mg Zn kg-1,grain yield was 165.48 Mg ha-1.Adding vermicompost to the soil at 20 Mg ha-1 achieving in available nitrogen in the soil of 43.74 mg N kg-1 soil,available phosphorus of 19.72 mg P kg-1 soil and available potassium of 196.93 mg K kg-1 soil.In the leaves,nitrogen was 4.37%,phosphorus was 0.44%,potassium 4.87%,iron was 182.63 mg Fe kg-1,zinc was 73.70 mg Zn kg-1 and grain yield was 168.43 Mg ha-1.Spraying nano-fertilizer on the plant at 150 mg L-1 achieved In the leaves,nitrogen 4.28%,phosphorus of 0.46%,potassium of 5.10%,iron of 204.83 mg Fe kg-1,zinc of 89.28 mg Zn kg-1 and manganese of 234.07 mg Mn kg-1 and grain yield was 172.88 Mg ha-1.
基金Supported by Special Project for the Construction of the National Modern Agricultural Industry Technology System(CARS-04-CES16).
文摘The soybean and corn strip compound planting technology is a crucial measure for improving land use efficiency and ensuring food security.This paper deeply analyzed the principles,advantages,and key technical aspects of this technology,including variety selection,planting pattern,sowing management,and field management.It also illustrated its application effectiveness through practical cases and proposed corresponding solutions to existing challenges in its promotion.This study provides theoretical support and practical reference for the widespread adoption and efficient application of this technology.
基金Financial support for this research from Minnesota Corn Growers Association(Burnsville,MN,USA)Green Plains Energy(Omaha,NE,USA)is greatly appreciated.
文摘Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin synthesis.However,we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val,Trp,and(or)Ile.Methods Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with 4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were formulated.Seven additional diets were formu-lated by fortifying the basal diet with 20%CFP with Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-phase feeding program was used,with d 1 to 14 being phase 1 and d 15 to 28 being phase 2.Fecal scores were recorded every other day.Blood samples were collected on d 14 and 28 from one pig per pen.On d 14,fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial protein.These pigs were also euthanized and ileal tissue was collected.Results There were no effects of dietary treatments on any of the parameters evaluated in phase 1.Inclusion of 10%or 20%CFP in diets reduced(P<0.05)final body weight on d 28,and average daily gain(ADG)and average daily feed intake(ADFI)in phase 2 and for the entire experimental period.However,pigs fed the CFP diet supplemented with Val,Ile,and Trp had final body weight,ADFI,ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control diet.Fecal scores in phase 2 were reduced(P<0.05)if CFP was used.Conclusions Corn fermented protein may be included by up to 20%in diets for weanling pigs without affecting growth performance,gut health,or hindgut fermentation,if diets are fortified with extra Val,Trp,and Ile.Inclusion of CFP also improved fecal consistency of pigs.
文摘The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence.
基金supported by the National Key Research and Development Plan of China(grant number 2023YFC2604903)National Natural Science Foundation of China(grant number 22338013)+2 种基金Natural Science Foundation of Henan Province(grant number 242300421106)Henan Province Science and Technology Research and Development Plan Joint Fund Project(grant number 222103810063)Key Scientific and Technological Project of Education Department of Henan Province(grant number 23A210007).
文摘Enzymatic modification is an important approach to changing the structure and expanding industrial application of natural starch. In the process of starch modification, thermostable enzymes are favored owing to their compatibility with higher reaction temperatures and lower required dosage. In this study, thermostable glucoamylase from Thermothelomyces thermophilus(TtGA) was heterologously expressed in Pichia pastoris, and its effects on the structure and physicochemical properties of raw corn starch were determined. The purified TtGA had a molecular weight of approximately 66 kDa, and its optimum reaction temperature and pH were 50 ℃ and 5.0, respectively. TtGA retained > 60% of its activity following treatment at 60 ℃ for 2 h and remained stable within a pH range of 4.0–7.0 for 6 h. The enzymatic modification of raw corn starch with TtGA led to 3% hydrolysis at 50 ℃ for 24 h. In comparison with natural raw corn starch, TtGA-modified starch had a smaller particle size with an unchanged crystalline structure, increased relative crystallinity, and amylose content.Scanning electronic observation showed that larger pores were formed on the surface of starch particles, and Fourier-transform infrared spectroscopy indicated that TtGA increased the degree of order in the raw corn starch.TtGA modification caused enhanced viscosity of the raw corn starch and altered the rheological properties with decreases in storage and loss moduli, as well as shear viscosity. Moreover, TtGA treatment enhanced the thermal characteristics of the raw corn starch, and decreased gelatinization enthalpy. This study provides detailed evidence for TtGA modification of raw corn starch, which would be helpful for its practical utilization in starch modification.
基金supported by the National Key R&D Program of China(2022YFD1201802)the Shandong Key R&D Program,China(2022CXGC010607)+2 种基金the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ZDRW202109)the Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP2017-ICS)the Subproject of the Major Project of Science and Technology in Shanxi Province,China(202201140601025-1-02)。
文摘Southern corn rust(SCR)is an airborne fungal disease caused by Puccinia polysora Underw.(P.polysora)that adversely impacts maize quality and yields worldwide.Screening for new elite SCR-resistant maize loci or genes has the potential to enhance overall resistance to this pathogen.Using phenotypic SCR resistance-related data collected over two years and three geographical environments,a genome-wide association study was carried out in this work,which eventually identified 91 loci that were substantially correlated with SCR susceptibility.These included 13 loci that were significant in at least three environments and overlapped with 74 candidate genes(B73_RefGen_v4).Comparative transcriptomic analyses were then performed to identify the genes related to SCR infection,with 2,586 and 797 differentially expressed genes(DEGs)ultimately being identified in the resistant Qi319and susceptible 8112 inbred lines following P.polysora infection,respectively,including 306 genes common to both lines.Subsequent integrative multi-omics investigations identified four potential candidate SCR response-related genes.One of these genes is ZmHCT9,which encodes the protein hydroxycinnamoyl transferase 9.This gene was up-regulated in susceptible inbred lines and linked to greater P.polysora resistance as confirmed through cucumber mosaic virus(CMV)-based virus induced-gene silencing(VIGS)system-mediated gene silencing.These data provide important insights into the genetic basis of the maize SCR response.They will be useful for for future research on potential genes related to SCR resistance in maize.
文摘The objective of this study was to characterize the rumination time in lactating dairy cows fed with corn silage.Rumination time was recorded 24 h/day using direct visual observation.Six trials were conducted during 2018,2019 and 2020,and rumination time was recorded in 480-2-hour periods from 40 Holstein Friesian cows.In each trial,6 or 8 cows were selected and balanced for days in milk(DIM),milk production and number of lactations.Each cow was recorded continuously for periods of 2 h at a time to complete a full 24-h period per week(12 values per day).Data from all cows were associated with 4 reproductive statuses of cows:Inseminated(1-45 days after insemination),Open(45-150 days after calving),not-pregnant and pregnant.The longest rumination time(RT)was found in pregnant cows(average 536.9±29.87 min/day),and the shortest RT was in open cows(average 420.3±63.2 min/day).Inseminated and non-pregnant cows were found with intermediate values(527.3±82.4 min/day and 467.1±30.7 respectively).Significantly different RT means were found between pregnant and open cows(p<0.0001),pregnant vs.inseminated cows(p<0.0001),and between inseminated and open cows(p=0.0005).We concluded that some gynecological conditions of lactating cows affect the RT.Measurement of RT by visual observations proved to be acceptable for the conditions of this study when cows were housed indoors and were fed with partial mixed ration(PMR)based on corn silage.
基金funded by the 2022-2023 Australian Centre for International Agricultural Research(ACIAR)Alumni Research Support Facility(ARSF)programme:“Farmers’adaptive capacity and agricultural transformation in the Vietnamese Mekong Delta:understanding and supporting value chain engagement”the ACIAR-funded project“Farmer options for crops under saline conditions(FOCUS)in the Mekong River Delta,Vietnam”(SLaM/2018/144)to this study.
文摘Agricultural production(especially intensive rice production)is a primary income source for over 2.0×10^(7) people in the Vietnamese Mekong River Delta.However,adverse climate change impacts,socio-economic change,and high dependence on farm inputs for intensive production constrain the longer-term sustainability of rice systems.Government and agribusiness actors are encouraging more farmers to grow non-rice crops and supporting the upscaling of alternative crops to paddy rice.We used a qualitative approach to investigate the value chain characteristics,as well as constraints and opportunities of alternative crops via two case studies(baby corn and honeydew melon)in An Giang and Hau Giang provinces,Vietnam.Data collection involved focus group discussions with local farmers and interviews with farmers and industry experts.Thematic analysis was used to compile the findings,and the results were validated with local government staff.The baby corn value chain featured on-going and stable market demand(including value-addition)and better vertical coordination(e.g.,written contracts and financial support).The honeydew melon value chain featured positive relationships between farmers and traders despite less-developed vertical coordination.There are opportunities for value chain engagement through product quality certification,value-addition,and accessing high-value domestic and export markets.However,farmers require crop-specific and generic support from private and public sectors.Increased labour requirements and limited access to finance and credit limit value chain participation.Upscaling and marketing alternative crops can enhance farmer profitability and support non-farming agricultural business establishment,economic growth,and community development.Efficient value chains will be critical to ensure the adoption of alternative crops and development of crop-specific agribusiness models.These findings can inform policy-makers and change facilitators in designing targeted interventions to support the adoption of alternative crops in the study area as well as in Vietnam and globally.
文摘The widely consumed high-fructose corn syrup(HFCS) has been linked to neurological disorders. In a recent article published in Nature, Wang et al. extend the harms of excessive fructose intake on neurodevelopment to the prenatal and lactation stages. They reveal that fructose uptake via GLUT5 reprograms microglial metabolism towards a low-ATP production state, suppressing microglial phagocytosis and impairing neurodevelopment.
基金funded by the LatvianCouncil of Science,the project“Investigation of Eco-Friendly Thermal Insulation Materials from Sustainable and Renewable Industrial Crops Residuals,”number lzp-2021/1-0599.
文摘This study examines the development of loose-fill thermal insulation materials derived from annual plant residues,such as wheat straw,water reeds,and corn stalks,processed using the chemimechanical pulping(CMP)technique.The chopped plants were soda-cooked for 30 min,varying NaOH concentration(2%–8%on a dry basis of biomass),and mechanically refined using different disc types.The CMPprocess enhances the homogeneity and stability of defibratedmaterial,yielding improved insulation properties compared to untreated chopped rawmaterials.Chemical analysis revealed that CMP increases cellulose content and reduces lignin levels,enhancing water retention and vapor diffusion properties.Settlement tests confirmed that CMP materials are more resistant to compaction under vibration,maintaining long-term performance.Additionally,the CMP enables the production of lightweight materials that require less resource consumption while achieving comparable thermal insulation performance.The investigated biobased materials offer a sustainable alternative to conventional insulation,with competing thermal conductivity values(0.041-0.046 W/mK)at the settlement-resistant bulk density level of 60 kg/m^(3).The thermal conductivity of CMP materials remains minimally affected.However,the resulting fibers demonstrate significant advantages in stability and material efficiency.This highlights its suitability for loose-fill applications to improve the sustainability of the construction.Using renewable plant residues,CMP-based insulation materials align with circular economy principles and contribute to environmental sustainability.This research underscores the potential of CMP materials to reduce greenhouse gas emissions,optimize resource use,and promote eco-friendly building practices.
基金The National Key Research and Development Program of China(No.2016YFD0200700)from Ministry of Science and Technology,and the Chinese Universities Scientific Fund under Grand No.2017QC139&No.2017GX001,and helped by VIGA UAV Company(Beijing).
文摘Currently,unmanned aerial vehicles(UAVs)were widely applied to spray for pest and disease control.However,spray effect can be further improved by setting operation parameters more reasonably and scientifically.Therefore,this study attempts to derive the relationship between operation parameters and spray effect.Different growth stages were distinguished by various corn heights.A six-rotor UAV was operated at different heights and velocities to test pesticides spray effects for corns at different growth stages.Different plant canopy coverage rate and penetrating coefficients were obtained,according to which,the effects on droplet deposition rate caused by different UAVs’operation parameters were analyzed.Droplet penetrating coefficients were applied as indexes to evaluate and select UAVs operation parameters for corns at different growth stages respectively.Mathematical models of droplet penetrating coefficients with UAVs operation parameters were established for corns at all growth stages.The determination coefficients(R2)of all models were greater than 0.90 and average relative errors were within 20%,which asserted high forecasting accuracy of droplet penetrating rate.With the help of the models,parameters like operating height away from the bottom of corns and UAVs velocities were further analyzed,which guided the optimization of parameter settings and selection of spray methods for corns at different growth stages.
