Comparisons Of Grain Filing And Dehydration Rates In 4 Representative Varieties Of Maize In Northeast Provinces

Demeiyal, Xianyu335, Zhengdan958 and Danyu39 are different type hybrids which were the most dominant in the northeast provinces, were also the controlled hybrids of Liaoning Jilin and Heilongjiang province regional test. Xianyu335 was the most representative middle late hybrid which were launched by Pioneer Seed Company of American, and its market share is bigger; Zhengdan958 was Domestic dense planting resistant hybrid which had the largest national planting area; Demayal was an early maturity hybrid which were launched by France company has the largest planting area in the second accumulative temperature belt of Heilongjiang province, and dominant in Heilongjiang province; Danyu39 was the most representative and largest planted late-maturing maize hybrid of Liaoning province and was also breeding by Liaoning province itself, and in terms of yield, resistance and adaptability, etc were very outstanding.4 hybrids were used as material to make analysis and comparison for their grain filling rate, dehydration rate and the dry down rate of ears as well as the relative morphological indexes and physiological indicators. The results showed that:1. Xianyu335 among the 4 hybrids no matter in fresh weight or dry weight performed the highest grain weight and its grain filling rate was highest, and the grain moisture was lowest and the ear dry down speed was fast, while it’s average dehydration rate were in the medium level.Zhangdan958’s grain filling rate and dehydration rate were all in average level among the 4 hybrids, rapid filling duration lasting long and it’s grain weight was high;Demeiyal’s grain filling peak was high but its average grain filling rate was low and filling stage was shorter, it also had the minimum fresh and dry grain weight. Its grain dehydration rate was high and moisture at harvest had no advantage, but the ear dry down speed is fast;The moisture at harvest of Danyu39 was high and the grain weight was lower among the 4 hybrids. And the filling rate, grain dehydration rate or the speed of the ear dry down rate were all significantly lower than other varieties, comprehensive performance is the worst、2.The grain filling peak dry weight growth of each hybrids From big to small in the order Danyu39,Demayal,Xianyu335,Zhengdan958, they were 18.9g^ 18.6g-.16.9g and 15.5g respectively. The analysis results show that the grain dry weight growth of grain filling peak period can’t decide grain dry weight level.3. A hybrid that has high average moisture of husk and corncob, and its grain moisture content is also high; Husk and corncob dehydration rate fast hybrid its grain dehydration rate faster.4. The hybrid with a longer grain its moisture content is low, grain width and thickness have no relevant relationship with grain dehydration rate; During the whole grain filling period, the average filling rate is high, and its hundred grain weight and grain size are also high, but did not reach significant level; Ear length, ear rows showed no significant relationship with grain filling and dehydration rate.5. Leaf area index has no direct relation with grain filling and the dehydration rate; Chlorophyll content changes in the same direction with the grain filling rate, and high chlorophyll content result in high grain filling rate.6. Correlation analysis showed that the grain moisture content was positively related with bracts water content (r= 0.98, P< 0.01), positively correlated with cob moisture content (r= 0.93, P< 0.05); Grain dehydration rate negatively correlated with bracts dehydration rate (r= 0.42, P< 0.05),but positively correlated with cob dehydration rate(r= 0.60, P< 0.01); The grain moisture content negatively correlated with grain length (r= 0.93, P< 0.05), and were no correlation of grain width and grain thickness; Dehydration rate and grain length showed a negative correlation (r= 0.88, P< 0.05), has no correlation with the width and thickness of the grain; Hundred grain weight showed significant correlation with leaf area index, the correlation coefficient is 0.932 (P< 0.05); The grain dehydration rate and hundred grain weight showed significantly negative relationship, coefficient was 0.964 (P< 0.01); the grain volume also showed significant negative correlation with grain dehydration rate, the correlation coefficient is higher,0.974 (P< 0.01), seen from the grain hundred weight and volume, grain weight and grain volume is larger, the seed dehydration rate is smaller, the slower dehydration. Leaf area index was significantly negative correlation with the seed dehydration rate, the coefficient was 0.96 (P< 0.01); Chlorophyll content was positively correlated with the grain filling rate, reached significant level, correlation coefficient was 0.903 (P< 0.01). In this study, the leaf area index correlated with grain filling rate was not yet reached significant level.