氮肥运筹及密度对中优752源库关系和剑叶温度的影响

Effects of Nitrogen Application and Planting Density on Source-sink Relation and Temperature of Flag Leaf on Zhongyou 752

以三系籼型杂交中稻中优752为材料,研究了氮肥运筹及密度对其源库关系和剑叶温度的影响。研究表明:在适宜施氮量的情况下,适当增加中后期施氮比例和适度稀植都能提高粒叶比和库源增量比、降低生育后期根系活力的衰退值,有利于源库协调。粒叶比和库源增量比与产量均显著正相关,生育后期根系活力的衰退值与产量极显著负相关。增施氮肥、增加中后期的施氮比例及适度稀植能降低剑叶温度。抽穗期及抽穗后25 d剑叶温度与产量呈极显著负相关,而抽穗期剑叶温度与抽穗期的伤流强度极显著负相关。

The experiment of nitrogen application and planting density on source - sink relation and temperature of flag leaf was carried out with three -line indica hybrid middle season rice Zhongyou 752. The results were as follows： under suitable N application, increasing the N rate at middle - late stage and reducing planting density properly could increase the grain - leaf ratio and ratio of source to sink in increment, decrease the degradation ratio of root activity at later growth stage, and make source - sink coordination. There was significant positive correlation between grain yield and grain - leaf ratio as well as ratio of source to sink in increment, and significant negative correlation between grain yield and degradation ratio of root activity. High nitrogen application rate at middle - late stage and moderate planting density could reduce the temperature of flag leaf. There was a significant negative correlation between grain yield and the ten？.perature of flag leaf during heading and at day 25 after heading, and a significant negative correlation between the temperature of flag leaf and the bleeding strength during heading.