Study on Yield Formation Characteristics,Rice Quality and Growth Duration Variation of Fast-growing Japonica Late Rice

In order to investigate the ecological adaptability of late rice varieties for disaster relief after flood disaster,a sowing date experiment was carried out in Hunan with 8 Japonica rice varieties with different growth duration introduced from Northeast China. The results showed that:( 1) compared with the duration in origin,the growth duration of Japonica rice varieties which could normally mature Hunan became shorter by 15 ~ 45 d,their yield was 1. 43 ~ 9. 61 t / hm2,in which varieties sown in early July showed an average yield of 7. 51 t / hm2,shorter growth period,higher dry matter accumulation at maturity.( 2) In varieties could become mature normally,the overall performance of late maturing varieties was best, their showed higher yield and quality,and the next was special early ones,early maturing ones and mid-early maturing ones. Seen from disaster relief and improvement of rice quality in Hunan,late maturing Japonica rice varieties from Northeast China could be cultivated as late rice in Hunan,and their optimal sowing date was early July.