| Drought is an important limiting factor affecting the production of maize in China,it is the basis to determine the suitable drought-resistant index and to define the drought resistance characteristics of different inbred lines in different years and to select the drought-resistant inbred lines.In this study,31 maize inbred lines including 27 lines bred from Shaan A and Shaan B groups under many locations,low fertilization and low irrigation as materials and 4elite inbred lines(zheng 58,chang 7-2,PH6 WC and PH4CV)as controls,were planted under different irrigation conditions at 2 locations in 3 years.The drought resistance of 31 inbred lines was evaluated from the aspect of yield,the drought resistance grade of different inbred lines was analyzed,and the high yield and stable stability of the multiple environments were analyzed,and the materials which could be used as the parents were screened out.During the period of stress,the trumpet period was selected to flowering the grain yield under normal water supply and drought stress was measured at harvest time,and the Drought Resistance index was calculated based on the data of yield BLUP value,and the yield BLUP value and related drought-resistant index were analyzed by principal component analysis,and the drought-resistant index suitable for maize inbred lines was screened,The drought resistance of 31 inbred lines was evaluated by cluster analysis.Using GenStat to analyze the interaction between genotype and genotype and environment in different environments,to identify the drought resistance of 31 inbred lines at different places in different years,and to combine with the analysis of high yield and stable yield,to select excellent inbred lines with strong drought resistance,stable yield and good yield,which can be used as hybrids with parents,the characteristics of drought resistance evaluation in different places were clarified through the analysis of the yield GGE biplot in different locations.The analysis of the test results shows the following conclusions:1.Under drought stress,the yield BLUP value decreased by 24.33% to the Blup value of normal irrigation,reached moderate stress level,the yield blup value and related drought resistance index were closely related to 2 kinds of treatments,and the results of principal component analysis showed: Geometrical Mean Production(GMP),Stress Tolerance Index(STI),Drought Resistance Index(DRI)can be used as the evaluation index of maize inbred lines drought resistance;2.A cluster analysis of 31 maize inbred lines was conducted with the selected drought-resistance index,and the results showed that: 31 inbred lines were divided into 3groups.5 of inbred lines with strong drought resistance(KA105,2013KB-37,KB081,KB215,2012KA-58),and drought-resistant general inbred lines is 25,1 inbred line with poor drought resistance(HN008);3.Compared with the control materials,the results of cluster analysis showed that the drought resistance of the inbred lines selected by the Shanxi A and B groups was generally better than that of the control self inbred lines,which showed that under the guidance of the two direction grouping strategy,the maize inbred line selected by "high density,multi point,low nitrogen and drought" has generally better drought resistance;4.There are very significant differences between genotype,environment and G×E,the Environmental and G×E effects on yield are greater than genotype,and the results of GGE analysis based on yield shows that KA105,KA215,2012KA-58,KB081 and 2013KB-37 have better drought resistance,consistent with the results of cluster analysis,high and stable yield also are good,those lines can be used as hybrid’s parents;5.The results of GGE biplot analysis at different sites show that the results of the evaluation of inbred lines in yangling test sites vary widely,possibly due to the large rainfall in yangling test sites and controlling water in the field is difficult.The evaluation results of inbred lines in different years of Yulin test point were more stable,Yulin test Site is more suitable as a pilot for the evaluation of the drought resistance of inbred lines. |
PDF Full Text Request