不同育期施氮对水稻群体物质生产及分配的影响

Influence of applied nitrogen during different periods on matter production and distribution of rice colony

通过 8个基、蘖、穗肥不同施N比例及数量研究毕粳 37号群体物质生产及分配与积累。结果表明 ,至抽穗期群体干物质生产积累量与基肥施N比例、施N量呈线性关系。在基肥施N比例较低时 ,增加施N比例抽穗前群体增加的光合产物主要用于茎鞘的生长 ,单茎茎鞘重、茎鞘重 /叶重之比值逐渐提高 ;当基肥施N比例增加到适宜施N量的 75 %时 ,增加施N比例 (施N量 )所增加的光合产物主要用于叶的生长 ,茎鞘重 /叶重之比值开始降低。贮存在叶、茎鞘内的光合产物迅速运输到籽粒 ,将促进灌浆期源的光合作用及籽粒灌浆。当基肥施N比例为适宜施N量的76 %～ 77%时 ,抽穗前群体光合产物在叶、茎鞘之间的分配将实现灌浆期群体库大、源足、流畅的协调关系 。

Studies were attempted to the matter production,distribution and accumulation of rice Bijing 37 colony with 8 different nitrogen rate and quantity of base manure,tiller manure,and ear manure.The result indicates that dry matter′s production and accumulation of colony has linear relation with the nitrogen rate and quantity of base manure in ear sprouting period.If the nitrogen rate of base manure is low,the increase of nitrogen rate can speed up photosynthesis of colony,which results in stem growth,increase of individual stem weight and gradual enlargement of the ration of leaves weight.If the nitrogen rate of base manure increases to 75 percent of appropriate rate,the photosynthesis resulted from the increase of nitrogen rate mainly only leads to growth of leaves,but the ration of stems/leaves weight begins to decrease.The photosynthetic products stored in the leaves and stems is transported rapidly of source during filling period and seeds filling.When nitrogen rate of base manure increases to 76%-77% of appropriate rate,photosynthesis distribution between leaves and stems of colony before ear sprouting brings about balanced smooth flow,thereby achieve high yield.