Selection Of Atrazine Tolerant Germplasm Resources And Identification Of Growth,Development And Agronomic Traits Of Millet

The chemical structure of atrazine is relatively stable,and it is not easy to degrade in the environment.The residual period of atrazine in soil is relatively long.In order to study the effect of atrazine residue in soil on the drug damage of subsequent crops in maize field,the optimal concentration for drug resistance screening of millet was determined by studying the effects of different concentrations of atrazine solution on the germination potential,germination rate and death days of three millet varieties.A total of 100 different varieties of millet materials were used for screening of drug resistance during germination,and 20 materials were screened out according to the six indexes of germination potential,germination rate,germination index,vigor index,root length and bud length for further identification and analysis of drug resistance in field experiments.The aim of this study was to select germplasm resources with high yield,strong stress resistance and excellent comprehensive traits suitable for planting in areas with high atrazine residue,and to provide necessary basic guarantee for breeding new varieties.The main research results are as follows:1.Under the treatment of 0(CK),0.5 ml/L,1 ml/L,2 ml/L,3 ml/L atrazine solution,the germination potential and germination rate of Nenxuan 15,Longgu 25 and Gongai 5 were different,the germinating power and germinating rate of millet were significantly different with the increase of the concentration of atrazine,but the germinating rate of millet was not completely dead after 15 days of cultivation,when the concentration of atrazine was 2 ml/L,the millet died in 15 days,and when the concentration of atrazine was 3 ml/L,the survival rate of millet was very low,the whole millet died within 12 days of cultivation,and the screening effect might not be achieved Therefore,2ml/L atrazine is suitable as the optimum concentration for screening resistance of foxtail millet.2.The resistance of 100 millet varieties at germination stage was evaluated by 2 ml/L atrazi e solution.According to 6 indexes of germination potential,germination rate,germination index,vigor index,root length and bud length,the tested materials were divided into 4 grades of high t olerance,medium tolerance,medium sensitivity and high sensitivity,including 24 high toleranc e varieties,28 medium tolerance varieties,31 medium sensitivity varieties and 17 high sensitivi ty varieties.Six varieties were selected from high tolerance materials,four varieties were select ed from medium tolerance materials,five varieties were selected from high and medium suscept ible materials,a total of 20 millet varieties were used for field experiments.3.Under atrazine stress,the plant height,leaf area and dry matter quality of 20 foxtail millet varieties were obviously inhibited,and the degree of inhibition in early stage was higher than that in late stage The contents of Chlorophyll A,chlorophyll B,chlorophyll content,net photosynthetic rate,transpiration rate and stomatal conductance of millet leaves decreased in different degrees compared with the control The activities of SOD,POD and CAT,the contents of MDA and soluble protein in leaves of foxtail millet increased in different degree compared with the control.4.Gongai 2 and Caoguzi are the materials with strong comprehensive drug resistance,which can be further studied as high quality resources.