Studies on full heading time and optimized sowing dates of hybrid rice Liangyoupeijiu

The full heading time and opportune sowing date of Liangyoupeijiu as a late-season rice were studied as compared with Xieyou 9308 and Shanyou 63 in southern Zhejiang Province.The results of two-year experiments showed that opportune sowing date of Liangyoupeijiu was before 21 June.Spikelets per panicle and seed setting rate decreased when it was sowed after 21 June.Seed setting rate remarkably declined when it was sowed after 27 June.Liangyoupeijiu was sensitive to temperature and weak response to photoperiod.There was two day difference of duration from sowing to initial heading when Liangyoupeijiu was sowed from 12 June to 27 June.Duration from sowing to initial heading of Liangyoupeijiu was longer due to low temperature in spikelets differentiation when it sowed after 27 June.Low temperature during heading prolonged the duration of initial heading to full heading stage.In this study,Liangyoupeijiu wasn't much sensitive to low temperature in heading stage as compared with Xieyou 9308 and Shanyou 63.This research showed that it was safe to plant Liangyoupeijiu as late-season rice under the conditions of light and temperature in southern Zhejiang.