Studies On Suitable Maize Variety Screening And Density Regulation In The Semi-arid Area Of Western Jilin

Drought is one of the main environmental factors to limit maize growth and yield.This research screenied different maize varieties on drought resistance in view of the ecological characteristics of semi arid areas Taonan(annual rainfall about 400 mm)in western jilin province.In the research,28 main maize varieties in jilin province’s as experimental material,and determine the indicators of drought resistance in the seedling stage,seedling stage and whole growth period.The effect on maize morphological indexes,physiological and biochemical indexes and yield in the different period,different drought degree of drought stress under different density was studied.System research in the west of jilin semi arid zone under the condition of drought stress was studied,corn to obtain maximum yield and group properties under the best density,which will provide a scientific basis for the region to obtain high and stable yield of maize.Main conclusions are as follows:1、The effects on the physiological and biochemical indexes of 28 maize varieties under water stress were studied by using peg-6000 solution with different concentrations to simulate the water stress of different degrees.The results showed that when maize seed germination,germination rate,germination potential,long storage material transport rate,seeds,radicle length and germination indexes were influenced by the corresponding.As the degree of water stress intensifies,the damage rate is greater.In the preliminary screening,the varieties with strong drought resistance were zhengdan 958,Nonghua 101,Limin 33,Jinongda 935 and Shen yu 21.The varieties with weak drought resistance were Xinyu 9,Jidan 535,Jiandong28.2、The effects of water stress on the morphological characters,dry matter accumulation,root-shoot ratio and SPAD of 28 maize varieties under pot experiment were studied.The analysis of the subordinate value of integrated drought resistance at seedling stage showed that drought-resistant varieties were Zhengdan 958,Nonghua 101,Xianyu 335,Jinongda 935,drought resistance Longping 936,Jidan 535,Xinyu 9 and Jidan 68 were weaker.3、The research studied on the effects on maize yield,ear length,ear grain number,the hundred grain weight of drought stress in field conditions,and useing portable canopy precipitation,to control soil moisture content.The results showed that the growth and development of corn was inhibited and the yield decreased.Water stress had a direct impact on maize yield,with an average reduction of 10.1%in yield under non-irrigation conditions.Under the condition of water stress,the yields of Zhengdan 958,Nonghua101,Jinongda 935,Liangyu 8 exceeded 10000kg/hm~2,and those of Xinyu 9 and Jidan 535 were the lowest.The drought resistance index of 28 maize varieties was analyzed,and the drought index of Zhengdan958,Nonghua 101 and Jiagong 935 was higher,and the drought index of Jidan 535 was lower.This is consistent with the results of sprouting drought resistance index and seedling comprehensive drought resistance membership value analysis.4、Effects of maize varieties with different drought resistance on their growth and physiological characteristics under water stress at seedling stage were studied.The results showed that after the seedlings were treated with different degrees of drought stress,the plant height,leaf area index,dry matter accumulation and chlorophyll content of maize seedlings were all lower than those of the normal water supply.With the increase of PEG concentration,the effect of seedling gradually increased,and the drought-resistant maize varieties had a lower decline rate than those with weak drought resistance.The root-shoot ratio of maize seedlings increased more than that of normal water supply.Under drought stress,proline content,soluble protein and soluble sugar content of different varieties of maize plants responded to drought.With the prolongation of PEG treatment,proline content,soluble protein and soluble sugar content increased firstly and then decreased in the leaves and roots of seedlings,and drought stress had a significant effect on malondialdehyde content in leaves with the extension of drought stress treatment time,MDA content increased gradually.In the four varieties,MDA content of Zhengdan 958 was significantly lower than the increase of Jidan 535.Drought stress had a significant effect on SOD activity in roots,but had a significant effect on POD activity in leaves.5、The results showed that the effect of drought stress at jointing stage on the plant height,stem diameter and leaf area index of maize was more obvious than that under drought stress.Water stress large impact on corn production.The influence of water stress on maize yield varied with maize varieties,drought occurrence period,drought stress level and drought duration.In this study,the planting density of zhengdan958 under adequate water conditions was 70000~80000/hm~2,and the planting density under dry conditions was 60000~70000/hm~2.The planting density of Jidan 535 under adequate water conditions was 60000~70000/hm~2,and the planting density under dry conditions was 55000~65000/hm~2.