杂交水稻始穗期氮钾营养对剑叶生理特性的影响

Effects of N,K Supply at Initial Stage of Panicle Emerging on Physiological Traits in Flag Leaf of Hybrid Rice Shanyou 63

采用盆栽试验研究了杂交水稻汕优63在施基肥的基础上，始穗期供给NK营养对剑叶生理特性的影响。施用NK，可促进剑叶叶绿素含量、光合速率、蔗糖磷酸合成酶（SPS）、过氧化物酶（POX）、超氧物歧化酶（SOD）、硝酸还原酶（NR）活性提高，呼吸速率下降，增加剑叶的可溶性糖和可溶性蛋白含量及根系活力，加速14C－同化物从剑叶的输出，提高14C－同化物在稻穗的分布积累及输入积（IAP）。讨论了始穗期共施NK营养提高结实率、谷粒充实度及稻谷产量的良好效果。

In pot experiment, the physiological traits in flag leaf of hybrid rice Shanyou 63 were studied under nitrogen, potassium, and nitrogen plus potassium supply at initial stage of panicle emerging. The nitrogen plus potassium supply at initial stage of panicle emerging, increased the chlorophyll content, photosynthetic rate and activities of sucrose phosphate synthetase (SPS), peroxidase (POX) , superoxide dismutase (SOD) and nitrate reductase (NR),but decreased the respiration in flag leaf at heading, milky and dough stage of hybrid rice Shanyou 63, enhanced the soluble sugar content and soluble protein content of the leaf as well as improved activity of the root system. The 14C-metabolites translocated more from flag leaf, distributed more in panicle and IAP [14C export from flag leaf(%)×14C in panicle(%)×100] when N plus K supplied to the soil in pots at initial heading stage than those of other treatments. It may be an innovative agricultural technology to increase the filled grain percent, 1000-grain weight and grain yield by N plus K supply at initial panicle emerging stage.