施氮时期对“扬稻6号”水稻谷壳生长和谷粒充实度的影响

Effects of Nitrogen Application Date on Hull Growth and Grain Plumpness of Rice Variety "Yangdao 6

设计基肥、分蘖肥、促花肥、保花肥、粒肥等 7个施氮期处理 ,研究其对“扬稻 6号”谷壳生长、谷粒充实及粒重的影响。结果表明 :与不施肥相比 ,施用基肥有利于扬稻 6号谷壳增大 ;施用粒肥有利于谷粒充实 ;施用分蘖肥既可促进谷壳增大 ,又可促进谷粒充实 ,从而使粒重显著增加 ;施用促花肥、保花肥或在基肥的基础上过多施用穗粒肥 ,虽可增加籽粒的充实度 ,但使谷壳明显变短变窄 ,粒重比对照显著降低 ;粒重与谷壳的长度、宽度和投影面积均呈极显著正相关 ,相关系数依次为 0 9396 、0 94 86 和 0 9894 ;

The experiments were carried out with indica rice cultivar'Yangdao 6'.Influence of N application date on hull growth,grain plumpness and grain weight of Yangdao 6 are analyzed.Compared with CK(no N application),N applied as basal dressing was beneficial to hull enlargement,N applied as granulated fertilizer contributed to high grain plumpness,and N applied at tillering stage was conductive not only to hull enlargement,but also to grain filling,so that grain weight were increased.Although,N applied as spikelet promoting fertilizer or spikelet sustaining fertilizer could increase the grain plumpness,the hull got shorter and narrower,which resulted in the visible decrease of grain weight.Grain weight showed the most significantly positive correlation with hull length,hull width and hull area( r in turn were 0 939 6  ,0 948 6  and 0 989 4  ).Grain weight mainly depended on the hull size.