不同玉米品种氮素营养效率差异的生态生理机制

Eco-physiological mechanism on nitrogen use efficiency difference of corn varieties

采用大田与盆栽试验相结合的方法 ,对 7个氮素营养效率不同的玉米杂交种在不同氮肥水平下的子粒日产量、吸氮效率、根系形态、叶片硝酸还原酶活力 (NRA)及冠层光合生理生态特性等进行了研究。结果表明 ,DK743、DK656、豫玉 2 2、中单 2号、户单 1号等 5个品种N素营养效率较高 ;酒单 2号和石玉 90 5是低N素营养效率的品种。N素营养效率的高低与品种根重、根长、根表面积、叶片NRA、净光合速率、气孔导度等都有一定的相关性。适当供氮能提高净光合速率、气孔导度、叶片NRA含量、干物质积累量和子粒产量 ,提高幅度因品种而异。

By use of field experiments and pot culture experiments, seed yield per day, nitrogen absorption efficiency, root morphology, leaf nitrate reductase (NRA), canopy photosynthesis eco physiological characteristics etc. were studied with 7 different corn varieties The results showed that 5 varieties of DK743, DK656, YY22, ZD2 and HD1 had high nitrogen use efficiency (NUE), but another two varieties of JD2 and SY905 had low NUE NUE were correlated with root dry weight, root length, root surface area, leaf NRA, net photosynthetic rate (Pn), stoma resistance(Sr) etc Pn, Sr, leaf NRA, total dry matter, seed yield were increased by more N applying, and the range of increasing were different among 7 varieties