氮肥运筹及密度对中优752源库关系和剑叶温度的影响

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。

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

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 temperature 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.