大穗型杂交中籼稻灌浆特点及不同天气对其灌浆的影响

The Grain Filling Characteristics of Large Panicle Mid-Season Indica Hybrid Rice Influenced by Different Weather

以大穗型杂交中籼稻隆两优华占、峰两优938、皖稻187、Y两优900、湘两优2号、超优1000为材料,将这些材料的穗部分成"穗上部"、"穗中部"、"穗下部"3个部分,每个部分再把一次枝梗子粒和二次枝梗子粒分别分成"上部"、"中部"、"下部"3个粒位,合计18个子粒部位。2014和2015年采用灌浆结实期田间跟踪取样的方式,对不同年份不同播期的种植材料进行考察,对比研究不同子粒部位的灌浆特点。结果表明:在一次枝梗子粒中,是靠近二次枝梗的"下部"子粒优先灌浆,遵循"下部"子粒优先于"中部"子粒、"中部"子粒优先于"上部"子粒的灌浆规律,在灌浆过程中,其受精粒率增幅呈现前期大、后期小的特点;在二次枝梗子粒中,是靠近一次枝梗子粒的"上部"子粒优先灌浆,靠近穗轴的"下部"子粒最后灌浆,在灌浆过程中,其受精粒率增幅呈现前期和后期小、中期大的特点。子粒灌浆在灌浆前、中期以一次枝梗子粒为主,受精粒千粒重表现是:穗上部一次枝梗>穗中部一次枝梗>穗上部二次枝梗>穗下部一次枝梗>穗中部二次枝梗>穗下部二次枝梗;在灌浆中、后期以二次枝梗子粒为主,受精粒千粒重表现是:穗上部一次枝梗>穗中部一次枝梗>穗下部一次枝梗>穗上部二次枝梗>穗中部二次枝梗>穗下部二次枝梗。大穗型杂交中籼稻在长期阴雨、严重缺少光照或光照强度太弱情况下,出现子粒同化物减少而导致结实率和千粒重降低。

The medium indica hybrid Longliangyouhuazhan, Fengliangyou938,Wandao187,Y liangyou900, Xiangliangyou2,Chaoyoul000 was used as material, the panicle of these materials was divided into 3 parts： the upper part of the panicle, the middle part of the panicle and the lower part of the panicle, each part then was divided the primary branch grain and the secondary branch grain into the upper part, the middle part and the lower part 3 grain positions, and altogether 18 sub particle parts. In 2014 and 2015, the planting materials of different years and different sowing dates were examined by field sampling in the grain filling stage, and the grain filling characteristics of different grain parts were compared. The results showed： In the primary branch, the grains close to the secondary branch or the ＂lower＂ grains had the priority for filling, followed by the ＂central＂ grains, and then the ＂upper＂ grains. In the grouting process, the fertilization rate of grain was bigger at the earlier growing stage, but smaller at the later growing stages. In the secondary branch grain, the trend was opposite, the grains were filled from the top to lower. For large panicle hybrid indica rice, in case of the long rainy, serious lack of light or too weak light intensity, the assimilated materials could be reduced and the seed setting rate and grain weight could be decreased.