Effects of Light Planting with Small Seedlings on Yield Formation in Single - cropping SeasonSuper Rice

摘要

The effects of light planting with small seedling on the yield formation in single cropping super rice Ganya 1 and Zhongyou 752 were studied in this paper, the results indicated that transplanting small seedling had significant advantages at early growth stage including rapid increase of leaf area at early stage, high net assimilation rate, much production of dry matter, quick emergence of tillers, especially many tillers on low node, plenty of valid panicles, which were benefit to high yield, but it had also some disadvantages such as low percentage of earbearing tiller, being prone to premature decay at late stage, low harvest index etc; light planting was favorable for overcoming above- mentioned shortages, the suitable transplanting seedlings for Ganya 1 and Zhongyou 752 were 1.0 ～ 1.1 million /hm~2 and 0. 75 ～ 0. 85 million /hm~2 main stem seedlings respectively ; the high - yielding cultural techniques of super rice were put forward as follows: on the basis of reasonable sparse transplanting with small seedlings, increasing the proportion of fertilization in middle and late period, drying the field in the sun in good time with a view to controlling invalid tillers and avoiding premature decay at late stage.