Comprehensive Evaluation Of Drought Resistance Based On Three Water Control Conditions In Maize Varieties

Drought is the first limiting factor restricting the development of Chinese maize industry.It is very important to cultivate and screen new maize varieties with strong drought resistance.In order to identify the drought resistance ability of different maize varieties and select the varieties with strong drought resistance accurately.This study selected eight approved maize varieties.In 2019 and 2020,based on three water control conditions including field planting,artificial water control in drought shed and hydroponics test,were comprehensively evaluated the drought resistance by the agronomic characters,physiological indexes and yield characters,and then using them to establish an efficient evaluation system for drought resistance of maize varieties.The results as follows:1.Under field planting,based on 2 years 5 pilot yield,DRI and GGE biplot analysis,LC825,SD650,JSH2468 and MC703 yield under drought and irrigation,better stability,big DRI,is a drought resistant variety,the results show that the ASI is short,the accumulation is more,the SPAD is higher,the stem strength and root activity are stronger.2.Under the drought shed cultivation,through the analysis of yield,DRI and GGE biplot of 2 kinds of water treatment conditions,MC703,SD650,JSH2468 and LC825 higher yield and higher DRI under drought and irrigation conditions,belong to drought resistant varieties.Show that the ASI is shorter,the SPAD and green leaves is higher,the root system activity is stronger,and the variation amplitude is smaller under drought conditions and the character value is stable.3.Under the condition of hydroponics,the drought-resistant varieties MC703、JSH2468,SD650 and XY335 showed more developed roots,more dry matter,better protective enzyme activity,higher and stable Phi₂and SPAD,higher leaf thickness and higher NPQ under the two water conditions.4.Through 2 years 5 point field experiment and 2 years dry shed experiment to screen the varieties with strong drought resistance,MC703,SD650,JSH2468 and LC825.Hydroponic test and field,drought shed screening drought-resistant varieties are MC703,SD650,JSH2468.In order to improve the efficiency of drought resistance evaluation of maize varieties,the drought resistance test of adult stage can be replaced by drought shed test.Hydroponic culture is mainly used to identify drought resistance in seedling stage,the test results are different from that in adult stage.5.Based on the identification results of drought resistance in field,dry shed and hydroponics,the stable drought resistant varieties MC703,JSH2468 and SD650 were selected.It is suitable for demonstration and popularization of maize varieties with high drought resistance and high yield and stable yield.To sum up,to comprehensively evaluate the drought resistance of maize varieties,Based on the indicators of first trait（yield,DRI）,second trait（root system,ASI,SPAD,green leaves and dry matter accumulation）and so on,the results of three water control conditions of field,drought shed and hydroponics were evaluated.