Study On Chilling Tolerance And Regulation Effect Of Maize

Chilling stress is the main factor affecting spring maize yield and quality traits in northeast China. Seed germination under chilling stress affects the subsequent growth, development and yield. Therefore, the research for identification of cold tolerance of maize and low temperature regulation of seed is very necessary. Low temperature identification of maize germplasm and low temperature regulation were used in this study. The results were as follows:1.Under chilling stress, the research screened 106 inbred lines, 40 recombinant inbred lines and 31 hybrid combinations which the germination rates were higher than 80%. High cold tolerant inbred lines were likely to be found among Reid group.2.Under chilling stress, maize inbred lines’ germination potential, germination rate, root length and shoot length were extremely significantly correlated. The germination potential and germination rate were high positive correlated, the correlation coefficient was 0.751. Other traits were positive moderate correlated, the correlation coefficients were between 0.300 and 0.700.3.Under chilling stress, Nongda 108 recombinant inbred lines’ germination potential and germination rate, root length and shoot length were significantly correlated, the correlation coefficients were 0.639 and 0.758. Other traits were not significantly correlated.4. Under chilling stress, Zheng 58 hybrid combinations’ agronomic traits were significantly correlated, the correlation coefficient were between 0.500 and 0.800. Chang 7-2 hybrid combinations’ agronomic traits also showed significant correlation, the correlation coefficients were between 0.500 and 0.900.5. Under normal temperature, coated seeds for the research had inhibitory effect on seed germination. Compared with CK, complex coated seeds’ root length decreased by 47%, shoot length decreased by 18%. Single coated seeds’ root length decreased by 22%. While coated seeds didn’t affect obviously under chilling stress. The coated seeds can improve seedling rate under chilling stress. 60% soil moisture content for 15 days under chilling stress, single coated seeds’ seedling rate was 2.4 times as much as the control’s, complex coated seeds’ seedling rate was 13.3 times as much as the control’s. Complex coating had significant promotion on seedling rate.6. Under normal temperature or chilling stress, seeds soaked in 0.01% Br had no obvious influence on seed growth and physiological and biochemical indexes.