Morpho-Physiological,Biochemical and Molecular Adaptation of Millets to Abiotic Stresses:A Review

Abiotic stresses such as drought,heat,cold,nutrient deficiency,excess salt and hazardous metals can hamper plantgrowth and development.Intensive agriculture of only a few major staple food crops that are sensitive and intolerant to environmental stresses has led to an agrarian crisis.On the other hand,nutritionally rich,gluten free and stress tolerant plants like millets are neglected and underutilized.Millets sustain about one-third of the world’s population and show exceptional tolerance to various abiotic and biotic stresses.Millets are C4 plants that are adapted to marginal and dry lands of arid and semi-arid regions,and survive low rainfall and poor soils.Abiotic stresses significantly affect plant growth which ultimately results in reduced crop yields.However,various adaptation mechanisms have evolved in millets to withstand different stresses.This review aims at exploring various of these morphophysiological,biochemical and molecular aspects of mechanisms in millets.Morphological adaptations include short life span,smallplant height and leaf area,dense root system,adjusted flowering time,increased root and decreased shoot lengths,high tillering,and leaf folding.A high accumulation of various osmoprotectants(proline,soluble sugars,proteins)improves hyperosmolarity and enhances the activity of antioxidant enzymes(e.g.,Ascorbate peroxidase,Superoxide dismutase,Catalase,Peroxidase)providing defense against oxidative damage.Physiologically,plants show low photosynthetic and stomatal conductance rates,and root respiration which help them to escape from water stress.Molecular adaptations include the upregulation of stress-related transcriptional factors,signalling genes,ion transporters,secondary metabolite pathways,receptor kinases,phytohormone biosynthesis and antioxidative enzymes.Lack of genetic resources hampers improvement of millets.However,several identified and characterized genes for stress tolerance can be exploited for further development of millet resilience.This will provide them with an extra characteristic plant resistance to withstand environmental pressures,besides their excellent nutritional value over the conventional staple crops like rice,wheat and maize.

Technological advancements in millet dehulling and polishing process: An insight into pretreatment methods, machineries and impact on nutritional quality

Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. This article primarily focuses on the advanced technologies and progressions in millet dehulling and polishing. These technologies operate based on the fundamental principles of compression-shearing, abrasion-friction, and centrifugal-impact forces. Processing of millets can be challenging because of the physical characteristics and tight attachment of hull and bran to the endosperm. However, several dehullers have been designed to solve this problem for different kinds of millets. In addition, the nutritional and anti-nutritional characteristics undergo alterations due to both dehulling and polishing processes. These alterations are thoroughly examined and discussed in this article. Specifically, anti-nutrients such as tannins and phytate are predominantly found in the outer pericarp of the grain and experience a reduction after undergoing dehulling and polishing. The nutritional properties are also subjected to a reduction;however, this reduction can be mitigated by subjecting the grains to certain pretreatments before dehulling and polishing. These treatments serve to enhance dehulling efficiency and nutrient digestibility while simultaneously reducing the presence of anti-nutrients. Novel thermal and non-thermal methodologies such as microwave, hydrothermal, high-pressure processing, and ohmic heating can be employed for processing millets, thereby diminishing the loss of nutrients. Additional research can be carried out to investigate their impact on the dehulling and polishing of millets.

Gene expression profiles in early leaf of rice(Oryza sativa)and foxtail millet(Setaria italica)

Plant anatomy is patterned early during leaf development which suggests studying the spatial–temporal transcriptomes of primordia will help identify critical regulative and functional genes.We successfully isolated the leaf primordia tissues from the C3grass rice and the C4grass foxtail millet by laser capture microdissection(LCM)and studied the gene expression throughout leaf developmental stages.Our data analysis uncovered the conserved expression patterns of certain gene clusters both in rice and foxtail millet during leaf development.We revealed genes and transcription factors involved in vein formation,stomatal development,and suberin accumulation.We identified 79 candidate genes associated with functional regulation of C4anatomy formation.Screening phenotype of the candidate genes revealed that knock-out of a putative polar auxin transport related gene NAL1 resulted significantly reduced veinal space in rice leaf.Our present work provides a foundation for future analyses of genes with novel functions in grasses and their role in leaf development,in particular the role in leaves with a contrasting C3vs.C4biosynthetic pathway.

Gut microbiota remodeling drived by dietary millet protein prevents the metabolic syndrome

Metabolic syndrome(Met S)is a chronic disease associated with the disturbance of gut microbiota homeostasis.Metabolites derived from gut microbes play essential roles in Met S prevention and therapy.Here,we focused on the inhibitory effect of the extract of millet bran protein(EMBP)on a high-fat diet(HFD)-induced Met S,aiming to identify gut microbiota and their metabolites that involve in the anti-Met S activity of EMBP.The obesity,chronic inflammation,insulin resistance in Met S mouse models were abolished after EMBP treatment.The protective mechanism of EMBP against HFD-induced Met S may depend on improved gut barrier function.Using microbiome analysis,we found that EMBP supplementation improved gut microbiome dysbiosis in Met S mice,specifically upregulating Bacteroides acidifaciens.The fecal microbiota transplantation(FMT)also demonstrated this phenomenon.In addition,metabolomic analysis showed that EMBP mediates metabolic profiling reprogramming in Met S mice.Notably,a microbiota-derived metabolite,gamma-aminobutyric acid(GABA),is enriched by EMBP.In addition,exogenous GABA treatment produced a similar protective effect to EMBP by improving NRF2-dependent gut barrier function to protect HFDinduced Met S.The results suggest that EMBP suppress host Met S by remodeling of gut microbiota as an effective candidate for next-generation medicine food dual purpose dietary supplement to intervene in MetS.

SiRAP2-12,a Positive Regulatory Factor,Effectively Improves the Waterlogging Tolerance of Foxtail Millet(Setaria italica)

Foxtail millet(Setaria italica)growth was inhibited because of waterlogging stress,which has caused yield reduc-tion.ERF family plays an important role to plant adversity tolerance.In our study,we obtained 19,819 differential expressed genes(DEGs)between the two treatments based on the RNA-seq sequencing of foxtail millet of water-logging stress.Furthermore,a total of 28 ERF family members were obtained,which have a complete open read-ing frame.We studied the evolution and function of SiERF family and how they affected the waterlogging tolerance.It was found that SiERF1A/B/C(GenBank ID:OR775217,OR775219,OR775218)and SiRAP2-12(GenBank ID:OR775216)have similar functions to the known waterlogging tolerance genes of other plants.Among them,the SiRAP2-12 expression was obviously significantly up-regulated in foxtail millet after 5d water-logging stress.After SiRAP2-12 was silenced,the activity of defense enzymes in millet decreased significantly.In details,superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD),the osmotic regulator proline(Pro),and the activity of the anaerobic respiratory enzyme alcohol dehydrogenase(ADH)content were decreased by 78.61%,29.52%,79.95%,19.41%and 54.77%,respectively.In contrast,the relative electrical conductivity contents(REC),malondialdehyde(MDA),and hydrogen peroxide(H_(2)O_(2))of the foxtail millet subjected to virus-induced gene silencing clearly increased by 1.03-fold,36.09%,and 15.21%,respectively.The content of sodium(Na^(+))in the SiRAP2-12-silenced foxtail millet also increased,but that of potassium(K^(+))decreased.Interestingly,we found that ethylene content was significantly reduced.Further,the SiAOC1 expression,an essential gene for ethylene synthesis,was inhibited in SiRAP2-12-silenced foxtail millet after waterlogging stress.Taken together,we hypothesized that SiRAP2-12 might be a positive regulator of millet tolerance to waterlogging stress.

Hydrothermal treatment of pearl millet grains:Effects on nutritional composition,antinutrients and flour properties

Pearl millet(Pennisetum glaucum)is one of the major millets with high nutritional properties.This crop exhibits exceptional resilience to drought and high temperatures.However,the processing of pearl millet poses a significant challenge due to its high lipid content,enzyme activity,and presence of antinutrients.Consequently,it becomes imperative to enhance the quality and prolong the shelf life of pearl millet flour by employing suitable technologies.Hydrothermal treatment in the food industry has long been seen as promising due to its potential to reduce microbial load,inactivate enzymes,and improve nutrient retention.This study aims to investigate the effects of hydrothermal treatment on the quality characteristics of pearl millet.The independent variables of the study were soaking temperature(35,45,55℃),soaking time(2,3,4 h),and steaming time(5,10,15 min).Treatment conditions had a statistically significant effect on nutrient retention.Major antinutrients like tannins and phytates were reduced by 0.99% to 5.94% and 0.36% to 6.00%,respectively,after the treatment.Lipase activity decreased significantly up to 10% with the treatment conditions.The findings of this study could potentially encourage the use of pearl millet flour in the production of various food items and promote the application of hydrothermal treatment in the field of food processing.

Effects of Seeding Date and Density on Yield and Agronomic Traits of Millet : A Case Study of Wangu 098 Variety of Millet

[Objectives]To find out a suitable cultivation technique of Wangu 098 in Nanyang area,speed up the popularization,demonstration and application of Wangu 098,and provide a theoretical and practical basis for adjusting the planting structure and realizing the matching of improved varieties and methods.[Methods]The new self-bred millet variety Wangu 098 was used as the material,and the two-factor split zone experimental design was adopted.The effects of different sowing dates and densities on the yield,growth period and agronomic characters of millet were studied.[Results]The interaction of seeding date and density had a great effect on the yield and plant traits of millet.Millet yield was significantly and positively correlated with plant height,panicle length,single panicle weight,panicle grain weight and tiller number.[Conclusions]The reasonable combination of seeding date and density could give full play to the yield potential of millet.According to the experimental results and cultivation experience,the suitable seeding date of millet in Nanyang area is in the first and middle ten days of June,and the best density is about 750000 plants/ha.However,after June 30,the seeding millet did not tiller,so the density should be increased to more than 900000 plants/ha to obtain higher yield.In terms of cultivation and management,timely seeding,reasonable close planting,and coordination of vegetative growth and reproductive growth can make the plant tall and strong,panicle long and thick,and improve the yield of millet.

Millet Origin Identification Model Based on Near-infrared Spectroscopy

[Objectives]This study was conducted to clarify the difference of millet from different producing areas in near-infrared spectroscopy(NIRS)modeling.[Methods]Millet samples from six different regions were collected for NIRS analysis,and an origin identification model based on BP neural network was established.The competitive adaptive reweighted sampling(CARS)algorithm was used to extract characteristic wavelength variables,and a CARS-BP model was established on this basis.Finally,the CARS-BP model was compared with support vector machine(SVM),partial least squares discriminant analysis(PLS)and KNN models.[Results]The characteristic wavelengths were extracted by CARS,and the number of variables was reduced from 1845 to 130.The discrimination accuracy of the CARS-BP model for the samples from six producing areas reached 98.1%,which was better than SVM,PSL and KNN models.[Conclusions]NIRS can quickly and accurately identify the origin of millet,providing a new method and way for the origin identification and quality evaluation of millet.

Study of the Constraints of Millet Production (Pennisetum glaucum (L.) R. Br.) and the Peasant Perception of Biological Control in the Tahoua Region

Millet (Pennisetum glaucum (L.) R. Br.) is the Sahelian crop par excellence due to its adaptation to the particular production conditions in this region. Unfortunately, in recent years this crop has been threatened by very strong parasitic pressure and drought during the production period. The objective of this study is to analyze the main constraints of millet production and the solutions known to producers. A survey was carried out in November 2022 with a sample of 298 producers in five municipalities in the Tahoua region. The main constraints are drought and pressure from crop pests (locust, millet ear miner, floricultural insects) according to 57.9% of respondents. The millet ear miner is the most formidable pest according to 55% of respondents. Thus, the average yield obtained in a year of good production without the leafminer is 194 kg/ha and that obtained in a year of millet ear leafminer is around 27 kg to 43 kg/ha depending on the municipality. The yield obtained this last campaign after the attack of this leafminer varies from 64 to 77 kg/ha depending on the municipalities compared to a potential yield of over 1000 kg/ha. More than half of producers (58.1%) are unaware of the existence of biological control compared to only 12.5% who are aware of this alternative method. Work to popularize this technology is necessary in the five municipalities and the entire region in general.

Evaluation of Phytochemical Analysis and Total Phenol Content of Proso Millet and Barnyard Millet

Whole grains of proso and barnyard millets were sequentially extracted using different solvents(hexane,chloroform,ethyl acetate,and methanol).Phytochemical analysis was performed qualitatively,and the total phenolic content in the extracts of proso and barnyard millets was quantified.Alkaloids and cardiac glycosides were identified in all solvent extracts of both millets.Anthraquinone and glycosides yielded negative results in all solvent extracts of both millets.Among all the solvent extracts,methanol extracts of proso and barnyard millets showed the presence of major compounds such as flavonoids,terpenoids,amino acids,tannins,and phenolics compounds.The maximum amount of phenols was found in methanolic extracts of proso and barnyard millets(0.669±0.003 and 0.625±0.003),followed by the chloroform extract of proso and barnyard millets(0.284±0.002 and 0.257±0.003).The minimum amount of phenolics was found in the acetone extract of proso and barnyard millets.The methanol extract of both millets showed the presence of major compounds with high phenolic content.

Performance Evaluation of Novel Eco-Materials Composed of Millet Husks, Rice Husks, and Polystyrene

Managing agricultural waste and expanded polystyrene (EPS) poses significant environmental and economic challenges. This study aims to create composites from millet husks, rice husks, and recycled EPS, using a manufacturing method that involves dissolving the polystyrene in a solvent followed by cold pressing. Various particle sizes and two binder dosages were investigated to assess their influence on the physico-mechanical properties of the composites. The mechanical properties obtained range from 2.54 to 4.47 MPa for the Modulus of Rupture (MOR) and from 686 to 1400 MPa for the Modulus of Elasticity in Bending (MOE). The results indicate that these composites have potential for applications in the construction sector, particularly for wood structures and interior decoration. Moreover, surface treatments could enhance their durability and mechanical properties. This research contributes to the valorization of agricultural and plastic waste as eco-friendly and economical construction materials.

Physicochemical and structural properties of starches from non-traditional sources in China

In this study,we isolated starches from non-traditional sources,including quinoa,lentil,arrowhead,gorgon fruit,sorghum,chickpea,proso millet,and purple potato and investigated their morphology,physicochemical,and functional properties.Significant differences in starch particle morphology,swelling power,solubility,syneresis,crystalline pattern,and pasting viscosity were observed among the starches from these nontraditional sources.Further,all these isolated starches had unique properties because of their characteristic distinct granules when seen under scanning electron microscopy(SEM).The amylose content of the isolated starches shown significant difference(P<0.05),and the values ranged between 11.46%and 37.61%.Results demonstrated that the isolated starches contained between 79.82%to 86.56%starch,indicating that the isolated starches had high purity.X-ray diffraction(XRD)patterns of starches isolated from sorghum,proso millet,quinoa,purple potato,and gorgon fruit presented A-type diffraction pattern;while lentil seeds,arrowhead,and chickpea starches presented C-type diffraction pattern.Overall,these results will promote the development of products based on starch isolated from non-traditional starches.

Millet/peanut intercropping at a moderate N rate increases crop productivity and N use efficiency,as well as economic benefits,under rain-fed conditions

Cereal and legume intercropping has been widely adopted to increase crop productivity in sustainable farming systems worldwide.Among different intercropping combinations,millet and peanut intercropping can be adapted to most waterlimited areas.However,there are few studies on the differences in yield characteristics and nitrogen use efficiency between millet/peanut intercropping and monocultures under different nitrogen (N) application rates.The objective of this study was to determine the yield advantages and economic benefits,as well as the appropriate N application rate,of millet/peanut intercropping.A two-yearfield experiment was conducted with three cropping patterns (monoculture millet,monoculture peanut and millet/peanut intercropping) and four N rates (0,75,150 and 225 kg ha^(-1)).The results showed that the land equivalent ratio (LER) and net effect (NE) of the intercropping system reached their highest levels at the N input of 150 kg ha^(-1)in 2018 and 2019 (1.04 for LER,0.347 Mg ha^(-1)for NE,averaged across two years).Millet was the dominant crop in the intercropping system (aggressivity of millet and peanut (Amp)>0,competitive ratio of millet and peanut (CRmp)>1),and millet yields achieved their highest values at N inputs of 225 kg ha^(-1)for monoculture and 150 kg ha^(-1)for intercropping.NUE reached its highest levels with N inputs of 150 kg ha^(-1)for all planting patterns over the two years.Intercropping combined with an N input of 150 kg ha^(-1)achieved the highest net income of 2 791 USD ha^(-1),with a benefit-cost ratio of 1.56,averaged over the two years.From the perspective of economics and agricultural sustainable development,millet/peanut intercropping at 150 kg N ha^(-1)seems to be a promising alternative to millet or peanut monoculture.

Phosphorylation of SiRAV1 at Ser31 regulates the SiCAT expression to enhance salt tolerance in Setaria italica

Salinity severely affects plant growth and development.Thus,it is crucial to identify the genes functioning in salt stress response and unravel the mechanism by which plants against salt stress.This study used the phosphoproteomic assay and found that 123 of the 4000 quantitative analyzed phosphopeptides were induced by salt stress.The functional annotation of the non-redundant protein database(NR)showed 23 differentially expressed transcription factors,including a phosphopeptide covering the Serine 31 in the RAV(related to ABI3/VP1)transcription factor(named SiRAV1).SiRAV1 was located in the nucleus.Phenotypic and physiological analysis showed that overexpressing SiRAV1 in foxtail millet enhanced salt tolerance and alleviated the salt-induced increases of H_(2)O_(2) accumulation,malondialdehyde(MDA)content,and percent of electrolyte leakage.Further analysis showed that SiRAV1 positively regulated SiCAT expression to modulate the catalase(CAT)activity by directly binding to the SiCAT promoter in vivo and in vitro.Moreover,we found that phosphorylation of SiRAV1 at the Ser31 site positively regulated salt tolerance in foxtail millet via enhancing its binding ability to SiCAT promoter but did not affect its subcellular localization.Overall,our results define a mechanism for SiRAV1 function in salt response where salt-triggered phosphorylation of SiRAV1 at Ser31 enhances its binding ability to SiCAT promoter,and the increased SiCAT expression contributes to salt tolerance in foxtail millet.

Salt stress responses in foxtail millet:Physiological and molecular regulation

Foxtail millet(Setaria italica L.),a member of the Paniceae family,is a temperate and tropical grass species that is widely cultivated on the Eurasian continent.It is Chinese in origin and possesses a small genome,short growth cycle,and strong natural abiotic stress resistance.Elucidating the mechanism of millet tolerance to salt stress is becoming increasingly important with increasing soil salinization limiting crop productivity.The responses and mechanisms of tolerance to salt stress from other model plants such as Arabidopsis and rice,were compared with those from foxtail millet to summarize current research on responses to salt stress.Numerous processes are involved in these processes,including physiological reactions,sensing,signaling,and control at the transcriptional,post-transcriptional,and epigenetic levels.To increase crop productivity and agricultural sustainability,a variety of technologies can be used to investigate how salt tolerance is mediated by physiological and molecular processes in foxtail millet.

Integrated genomic and transcriptomic analysis reveals genes associated with plant height of foxtail millet

Foxtail millet(Setaria italica)is an important C4 model crop;however,due to its high-density planting and high stature,lodging at the filling stage resulted in a serious reduction in yield and quality.Therefore,it is imperative to identify and deploy the genes controlling foxtail millet plant height.In this study,we used a semi-dwarf line 263A and an elite high-stalk breeding variety,Chuang 29 to construct an F2 population to identify dwarf genes.We performed transcriptome analysis(RNA-seq)using internode tissues sampled at three jointing stages of 263A and Chuang 29,as well as bulk segregant analysis(BSA)on their F2 population.A total of 8918 differentially expressed genes(DEGs)were obtained from RNA-seq analysis,and GO analysis showed that DEGs were enriched in functions such as‘‘gibberellin metabolic process”and‘‘oxidoreductase activity”,which have previously been shown to be associated with plant height.A total 593 mutated genes were screened by BSA-seq method.One hundred and seventy-six out of the 593 mutated genes showed differential expression levels between the two parental lines,and seven genes not only showed differential expression in two or three internode tissues but also showed high genomic variation in coding regions,which indicated they play a crucial role in plant height determination.Among them,we found a gibberellin biosynthesis related GA20 oxidase gene(Seita.5G404900),which had a single-base at the third exon,leading to the frameshift mutation at 263A.Cleaved amplified polymorphic sequence assay and association analysis proved the single-base in Seita.5G404900 co-segregated with dwarf phenotype in two independent F2 populations planted in entirely different environments.Taken together,the candidate genes identified in this study will help to elucidate the genetic basis of foxtail millet plant height,and the molecular marker will be useful for marker-assisted dwarf breeding.

Considerations for gluten free foods-pearl and finger millet processing and market demand

The market demand for gluten free foods is increasing due to frequent incidences of celiac disease and increasing awareness on consumption of gluten free foods.Millets have become the major constituent of diet as they are gluten-free and also excellent sources of micro and macro nutrients such as vitamins,minerals,dietary fibers and phenolic compounds.Among various millets,the finger millet and the pearl millet are the two most important and common millet varieties grown extensively.Since,they are regarded as the staple foods of the poor and vulnerable populations,development of new products and improvements in their nutritional quality will aid in the general health of these population.Processing of millets and production of variable gluten-free ready-to-eat and nutritional supplements has increased their market value in the recent years.Furthermore,processing can also help in shelf-life extension of the millets with nutritional enrichment,expanding its markets to non-traditional millet consumers.In this context,the present review is aimed to focus on the current processing methods to develop products from the two millet varieties that are gluten free and outline their nutritional benefits.

Nutritional Composition and Anti-Nutrient Levels in Raw and Processed Varieties of Finger Millet Promoted for Nutritional Security

Finger millet (FM) is rich in nutrients such as minerals, vitamins, and amino acids. However, the levels of nutrients and their bioaccessibility depend on the variety, the levels of ant nutrients, the chemical form of nutrients, and the type of processing methods used. The study determined the levels of selected nutrients, anti-nutrients, and bioaccessibility in raw and processed varieties of finger millet being developed by the Kenya Agricultural and Livestock Research Organization (KALRO) in Kenya. Raw finger millet seeds from KALRO Centers in Kenya were processed by malting for 60 hours and roasting at 110°C for 5 minutes as the optimal conditions. Levels of minerals were determined by AAS and AES, anti-nutrients by UV-visible spectrophotometer, proteins by the Pierce kit method, and vitamins by HPLC. The IE4115 and IE3779 showed the highest levels of nutrients and lowest levels of antinutrients hence preferred for processing and bioaccessibility studies. The level (mg/100 g) of selected minerals;K, Cr3+, Mg, Ca, P, Fe, and Zn were found to be highest in the following varieties of the FM;IE3779 (688.519 ± 1.57), IE 4115 (1.29 ± 0.07), IE4115 (294.38 ± 1.93), IE3779 (466.67 ± 4.17), IE4115 (250.92 ± 0.33), KERICHO P (16.98 ± 0.05) and IE4115 (64.10 ± 2.35) respectively. For β-carotene, vitamin B, B2, B3, B6 and B9 the levels were highest in the following varieties of FM;KAKW3 (0.023 ± 0.02), IE4115 (14.85 ± 0.16), IE4115 (12.998 ± 0.04), IE4115 (5.843 ± 0.07), IE3779 (0.06 ± 0.04) and KAKW4 (9.832 ± 0.08). Phytates, tannins, phenols, and oxalates were found to be lowest in the following varieties: IE3779 (14.20 ± 2.90, IE4115 (27.83 ± 0.73), NKFM1 (9.69 ± 0.07) and IE4115 (0.25 ± 0.01). The highest bioaccessibility values reported for K, Mg, Ca, P, Cr3+, Fe, and Zn were 89.53% (malting, IE3779), 49.28% (malting, IE4115), 60.41% (Malting, IE4115), 69.40% (malting, IE4115), 12.9% (malting, IE4115), 59.84% (malting, KAKW3) and 66.89% (roasting, IE3779) respectively (Table 8). For beta carotene, vitamin B1, B2, B3, B6 and B9 the values were 73.33% (malting, p224), 78.84% (malting, IE4115), 78.34 (malting, IE3779), 97.63% (malting, IE4115), 91.64% (malting, IE4115), and 77.52% (roasting, IE4115) (table The result on levels and bioaccessibility showed that IE4115 and IE3779 varieties were more nutritious and therefore should be promoted for nutritional security.

Study on Safe Dosage of Imazethapyr for an Imazethapyr Resistant Millet Variety and Its Effect on Weed Control

[Objective] This study aimed to investigate the safe dosage of imazethapyr for an imazethapyr resistant millet variety and its effect on weed control. [Method] The Imazethapyr resistant millet ＂M1508＂ was used as the experimental material and the experiment was arranged in a split plot design with two factors： herbicide application time and herbicide dosage. Application time was taken as the main plot with six treatments： A1 （preemergence treatment）, A2 （postemergence treatment on the 3rd d）, A3 （postemergence treatment on the 6th d）, A4 （postemergence treatment on the 9th d）, A5 （postemergence treatment on the 12th d）, A6 （postemergence treatment on the 15th d）; spraying dosage（B） with nine treatments： B1 （0 ml/hm2 , taking water as control）, B2 （750 ml/hm2 ）, B3 （1 125 ml/hm2 ）, B4 （1 500 ml/hm2 ）, B5 （2 250 ml/hm2 ）, B6 （3 000 ml/hm2 ）, B7 （4 500 ml/hm2 ）, B8 （6 000 ml/hm2）, B9 （7 500 ml/hm2 ）; water was added at 675 kg/hm2 . [Result] Imazethapyr showed a good herbicidal effect, and the imazethapyr resistant new variety M1508 also had a high drug resistance; the dosage range of 750 -7 500 ml/hm2 was safe for millet; considering the weed control efficacy, the yield and weeding cost comprehensively, postemergence treatment on the 6th day at 1 500 -2 250 ml/hm2 was the best for herbicide application. [Conclusion] Matched chemical weeding techniques to imazethapyr resistant millet varieties were preliminarily identified, and the efficacy of imazethapyr on weed control and its security on millet were investigated, providing references for the application and promotion of imazethapyr resistant millet varieties.

Chemical Control of Herbicide Monosulfuron Plus Propazine 44% WP against Weeds in Millet Fields and Study on Factors Influencing Yield of Millet

[Objective] The paper was to resolve the poor efficacy or phytotoxicity problems in promotion of herbicide monosulfuron plus propazine 44% WP. [Method] Using orthogonal test and Duncan＇s new multiple range statistical analysis with four factors four levels and three factors two levels, the effects of factors such as herbi- cide dose, irrigation water volume, quality of soil preparation and soil moisture content on chemical control of monosulfuron plus propazine 44% WP against weeds and millet yield were compared in the test. [Result] Seven factors all had great impact on control effect of monosulfuron plus propazine 44% WP against weeds, of which her- bicide dose, irrigation water volume, quality of soil preparation and soil moisture content were the most important factors affecting millet yield. According to millet yield and economic benefit, the optimal scheme to ensure safe, efficient and economic control of monosulfuron plus propazine 44% WP against weeds was as follows： the dose of monosulfuron plus propazine 44% WP was 1 800 g/hm2, the soil was treat- ed after sowing and before seedling emergence; the soil should be smooth and sol- id; the soil moisture should reach 15%; the fields should not be irrigated after herbi- cide application, and the damage of weeds in millet fields could be effectively con- trolled within 45 d during high efficacy duration, especially the damage of dicotyledonous weeds. [Conclusion] The study provided useful information for comprehensive technology of weeds control and ensuring high yield and good harvest of millet.