Effects Of Transplanting Patterns On Population Development And Grain Yield

The hybrid rice varieties of different genotypes, Chuan Xiang 9838,â…¡You 498, Gang You 188 and Gang You 906, were used to study the effects of the resuming, growth and the impact on yield after transplanting, under different transplanting methods (optimizing cast-transplanting rice, transplanting rice and machine-transplanting rice). The results showed as follows:1. When the stem-tillers number attained peak value, the difference was significant between different transplanting methods. The stem-tillers number both optimizing cast-transplanting rice and transplanting rice were more 36.65% and 35.17% than machine-transplanting rice respectively. But the difference of percentage of productive tillers also was significant, and both optimizing cast-transplanting rice and transplanting rice were more 3.74% and 3.9% than machine-transplanting rice respectively. Among the hybrid rice varieties Chuan Xiang 9838 was the highest one, and the percentage of productive tillers ofâ…¡You 498 was higher than Chuan Xiang 9838 and Gang You 188.2. Root vigor after transplanting showed descendent direction. The root vigor of optimizing cast-transplanting rice and transplanting rice decreased by 38.28% 42.67%, and of machine-transplanting rice decreased by 17.35%. Root number and dry matter accumulation of root after transplanting first slowly increase, then speeding increase. But the difference of percentage of Root number and dry matter accumulation of root also was significant, and both optimizing cast-transplanting rice and transplanting rice were more 113.29% and 99.60% than machine-transplanting rice respectively. The stem bleed showed descendent direction. after initial heading stage, but root vigor of optimizing cast-transplanting rice decrease lowest. This showed that the stem bleed of optimizing cast-transplanting rice was better, also it was able to keep better root vigor, and delay the root senescence3. Dry matter accumulation and nitrogen accumulation increase with exponent model and they were lowest with machine-transplanting rice, but the increasing speed was slower than optimizing cast-transplanting rice and transplanting rice. The difference of percentage of dry matter accumulation and nitrogen accumulation among different transplanting was very significant, and dry matter accumulation both optimizing cast-transplanting rice and transplanting rice were more 115.60% and 98.17% than machine-transplanting rice, nitrogen accumulation were more 149.19% and 127.12%. The difference of percentage of dry matter accumulation and nitrogen accumulation among different varieties was not significant, but the Gang You 188's was highest.4. The total leaf area index was highest in initial heading stage, then gradually decreased, and lowest in ripening stage. The total leaf area index of optimizing cast-transplanting rice, transplanting rice and machine-transplanting rice decreased by 45.38%,43.46% and 44.39% respectively and the efficient leaf area index leaves decreased by 60.83%,59.24% and 57.25%. The total leaf area index with machine-transplanting rice was lowest, transplanting rice's was highest, and the efficient leaf area index of top three leaves with optimizing cast-transplanting rice was lowest, transplanting rice's was highest. The percentage with the efficient leaf area index was highest with optimizing cast-transplanting rice, lowest with transplanting rice. This established stable foundation for higher yield with optimizing cast-transplanting rice.5. The optimizing cast-transplanting rice and transplanting rice in heading stage was able to accumulated higher photosynthetic product and anaphase enriching quantity of photosynthetic, so they can provided assimilation product for grain filling and pledged the "fountain" of high-yielding rice. But machine-transplanting rice in heading stage can accumulated lower photosynthetic product and anaphase enriching quantity of photosynthetic, so it cause grain was less and grain filled not fully, also it has some influence on its production.6. The difference of yield among different transplanting was very significant (F=11.98**). The yield of optimizing cast-transplanting rice was tiptop and transplanting rice's was second, and machine-transplanting rice was lowest. The yield both optimizing cast-transplanting rice and transplanting rice were more 7.89% and 6.56% than machine-transplanting rice. The filled spike lets per panicle, grain per panicle and 1000-grain weight of optimizing cast-transplanting rice and transplanting rice were and the differences were significant or very significant. That was the direct cause of the yield is low.