两优培九稻米垩白率变异及其与气象因子的关系

Chalky Grain Rate Variation and Its Relationship with Meteorological Factors for a Two-line Hybrid Rice,Liangyoupeijiu

用2006年和2007年两优培九在南方稻区8个生态点33个种植试验的田间试验资料,分析了不同生态条件下两优培九垩白率的变异及其与气象要素之间的关系。结果表明,两优培九垩白率在扬州、武汉和江油等长江中下游稻区变异较大,在广州、南宁、海口等华南双季稻区变异次之,在云南涛源表现低而稳定。垩白率随播种期的推迟而变小。日平均温度对垩白率的影响最大,其次是日平均最低温度和日平均最高温度,降水量、日照和日较差的影响较小;齐穗后6-30 d日平均温度有显著影响,有利于两优培九垩白率达优质米标准的灌浆结实期温度为22-25℃。

Chalky grain rate can vary greatly with meteorological factors. In this study, an effort was made to correlate chalky grain rate with meteorological factors during grain filling stage for Liangyoupeijiu, a widely planted two-line hybrid rice in southern China, by using data from eight experimental plots in 2006 and 2007. The largest variation coefficient （CV） of chalky grain rate was presented in the rice areas of Middle and Lower Reaches of Yangtze River, including Yangzhou, Wuhan and Jiangyou, and the smallest one was produced in Taoyuan, an elite rice area in Yunnan plateau. Chalky grain rate of Liangyoupeijiu varied with the sowing time. In a certain extent, the later sowed, the smaller chalky grain rate produced. Correlation analysis showed that key meteorological factors affecting chalky grain rate were daily average temperature, then daily minimum temperature and daily maximum temperature, respectively. Sunshine hours, rainfall and daily temperature fluctuation （DTF） had less effect. Daily average temperature of 6 - 30 d after heading had a significant negative effect on the development of chalky grain rate. According to the response of chalky grain rate to daily average temperature, daily average temperature ranging from 22 ℃ to 25 ℃might be favorable for the decrease of chalky grain rate of Liangyoupeijiu.