不同耕作方式对机插双季水稻产量的影响

摘要

明确不同机械土壤耕作方式对机插双季水稻产量的影响有助于提高我国水稻生产的机械化水平。通过两年的田间试验，对比研究了深翻耕与农户浅旋耕对机插双季水稻产量的影响。结果表明，与旋耕相比，连续翻耕对水稻的生物量、产量以及产量构成均无显著影响。翻耕降低了抽穗后剑叶的叶绿素含量（ SPAD值），特别是早稻，但对早晚稻剑叶的净光合速率并无显著影响。与旋耕相比，翻耕有降低早稻植株氮素含量的趋势，而晚稻趋势不明显。翻耕显著提高了下层（10～20 cm）水稻根系的质量及其比例。但这种对水稻根系生长的促进作用并未带来地上部生物量或产量的提升。因此，在本试验点翻耕和旋耕之间机插双季水稻产量并无显著差异。%It plays a critical role in promoting the mechanization of rice production to examine the effect of different tillage regimes on rice yield under mechanical transplanting.A two-year field experiment was conduc-ted to investigate the effect of deep moldboard plowing ( MP ) as compared to farmers’ shallow rotary tillage ( RT) on double rice yield under mechanical transplanting.The results showed that there were no significant differences in rice aboveground biomass,yield and yield components between MP and RT.Compared with to RT,MP reduced the SPAD ( Soil-Plant Analysis Development) value of flag leaves after heading,particularly in the early rice season,whereas no significant differences in the net photosynthesis of flag leaves were found between MP and RT.Compared with RT,MP tended to reduce the nitrogen content of rice plants in the early rice but not in the late season.MP significantly increased the biomass and proportion of rice roots in the subsur-face (10~20 cm).However,the promotion of root growth under MP did not translate into the increase in aboveground biomass or rice yield.Therefore,these results suggest that there is no significant difference in rice yield between MP and RT at this experimental site.