Screening Drought Resistances For Corn Varieties And Its Analysis On Difference Of Maize Genotypes

Through in combats drought in against canopy plot experiment,the establishment normal water supply and moderate forces two moisture content processing arid,two treats of normal water supple and moderate water stress have been established through special plot experiment design against raining.With the contrast of Zhengdan 958,17 physiological and biochemical parameters,including plant height,the number of dead leaves of the plant floor,no ear plant rate,the area of ear leaves,ear length,100 kernel weight,grain yield and so on,have been determinated,comparied and evaluated for the 5 corn varieties including Danyu 39,Xianyu 335,Liangyu 88,Liaodan 565,Shenshi 21.It shows that the the drought resistancees among the other four corn varities are very similar with Zhengdan 958 except for Danyu 39.However,it indicates that there are some difference between corn varieties drought stress. And the most excellent one is Xianyu 335,the next Liangyu 88 and Liaodan 565,the last one Danyu 39.With the experimental materials of hybrids and its parental inbred lines,it has been studied for the drought resistances of different corn genotypes and their genetic law.Some parameters and indicators including plant height,leaf areas per plant,ratio between dried matter weight of cap and root,ratio between fresh matter weight of hybrids and its parents inbred lines,chlorophyll,leaf filtrate relative water content and so on,have been measured during the flower period.The results indicate that maize genotypes under drought stress,various morphological traits and physiological traits disproportionately have been affected and the output has also been influenced ultimately. (1)There are close relationship between drought resistance and these indicators including plant height,leaf area per plant,ratio between dried matter weight of cap and root,leaf filtrate relative water content,MDA.By using these targets the degree of adult plant against drought can be reflected and and the drought resistances among different genotypes also be compared. (2)Flowering water stress results in ear shorter,finer,reduced grain weight and it has become affective way by using drought resistance index to identify the different genotypes.(3)There are some corresponding relationship between drought resistances of hybrid and its parents inbred lines,but no obvious and significant law.