再生稻需氮特性和分次施氮的研究

本文着重探讨了不同施氮水平下促芽肥与长苗肥对再生稻氮素营养、生长发育和产量形成的影响。

Study on Nitrogen Requirement and Split Application of Nitrogen Fertilizer in Ratooning Rice

The effect of split application of nitrogen fertilizer, namely, the ratio of BF (bud fertilizer applied 15 days after full heading of the main crop) and TF(tiller fertilizer applied 1 day after harvest of the main crop) under different nitrogen rate on the njtrogen nutrition, growth and grain yield of ratooning rice was studied. The results were summarized as follows: The nitrogen absorption, translocation and distribution of ratoon plant were strongly influenced by the fertilizer application method, especially the TF rate. BF promoted the carbohydrate- and nitrogen-matabolism of the plant at the late growth period of main crop, thus enhanced the elon-gation and sprouting of the dormant bud, as a result, increased tillers and effective panicles of ra-toon crop. TF promoted the growth of ratoon plant, thus increased the percentage of filled spikelets and numbers of filled grains per panicle of ratoon crop. The proper ratio of BF and TF depended on nitrogen rate. Sufficient BF should be applied to insure more effective panicles, and adequate TF should be practised to obtain more filled grains per panicle. The ratio of TF to total nitrogen rate should be increased with increasing the total nitrogen rate.