Relationship of yield components and temperature and light factors for super double-cropping late rice

NING Jin-hua;LU Kui-dong;SONG Zhong-hua;ZHANG Yan-gui;ZHOU Yu;Agro-meteorological Station of Hunan Province;Meteorological Disaster Prevention and Mitigation Key Laboratory of Hunan Province;Institute of Meteorological Sciences of Hunan Province;

Yueyou 6135;;sowing date;;yield components;;accumulated temperature;;sunshine

Using the data of super rice Yueyou 6135 with different sowing dates in 2011-2013,the differences of yield components between different years and sowing dates were analyzed,and the relationship models between yield components and temperature,light and their combination were established based on daily temperature and sunshine data during yield formation. The results showed that the yield component of rice with later sowing date in the same year was relatively poor,and fluctuated between different years. As the sowing date delayed,the differences in yield component of rice at the same sowing date became greater among different years. The best sowing dates were from mid-June to early July. Accumulated temperature showed a down parabola relationship with grain number per spike,and when the accumulated temperature reached 873 ℃,the grain number per spike was the highest. The accumulated temperature and sunshine had convex down relationships with empty grain rate,and had convex up relationships with seed setting rate. When 700-920 ℃ accumulated temperature and ≥ 180 h sunshine were simultaneously met,super rice had higher seed setting rate and lower empty grain rate. The results of this study had important guiding significance to arrange sowing date and utilize climate resources rationally in regions of the middle and lower reaches of the Yangtze River.