光周期和有效积温对水稻分蘖角度动态变化的影响

通过田间播期试验、植物培养箱人工光周期和温度试验研究了水稻DI508分蘖角度动态变化特性与光周期和温度的关系.结果表明：不同播期(4月4日、5月5日、6月4日)条件下，大田DI508分蘖角度从半散生到渐趋直立的变化均发生在自然光周期变短(6月21日，夏至)后的10～15 d;在光周期条件下，DI508的分蘖角度同样具有动态变化特性，10 h光照处理可使分蘖角度提前从半散生向直立转变，14 h光照处理则延缓转变.温度处理对水稻分蘖角度的变化特性没有显著影响.

Dynamic changes of rice (Oryza Sativa L.) tiller angle under effects of photoperiod and effective accumulated temperature.

Using rice variety DI508 as test material, a field experiment of different seeding dates and a test with plant growth chamber were conducted to study the dynamic changes of rice tiller angle under effects of different photoperiod and effective accumulated temperature. Under field condition, the tiller angle of DI508 plants changed gradually into erect after 10〖KG-*2〗-〖KG-*7〗15 days of photoperiod becoming shorter (since the Summer Solstice on 21st June), irrespective of seeding dates (4th April, 5th May, and 4th June). Under controlled photoperiod, the tiller angle changed in the same way as in the field. Shorter lighting treatment (10 hours) advanced the tiller angle change, while longer lighting treatment (14 hours) delayed the change. Effective accumulated temperature had no effects on the tiller angle change of DI508.