不同生态稻区覆膜旱作稻氮营养生理及抗逆生理特性探讨

不同生态稻区生态环境和栽培管理方式不同,覆膜旱作稻氮营养生理和抗逆生理与常规水作稻有些异同,尤其是体内NO₃^--N和NH₄⁺-N含量及分布差异很大.杭嘉湖平原区覆膜旱作稻生长前期受干热天气影响,其分蘖期、拔节期、孕穗期体内NO₃^--N含量较水作稻有不同程度的降低,而NH₄⁺-N含量则极显著提高;金衢盆地覆膜旱作稻孕穗期体内NO₃^--N含量比常规水作稻高,根部NH₄⁺-N含量则显著降低,茎基部和叶片NH₄⁺-N含量有一定增加.正常气候条件下两生态稻区覆膜旱作稻孕穗期叶片硝酸还原酶(NR)活性和谷氨酰胺合成酶(GS)活性较水作稻均有不同程度的提高;丙二醛(MDA)、可溶性糖及脯氨酸(Pro)含量与水作稻相差不大,表明不同生态稻区的覆膜旱作稻可以通过不同的栽培管理模式,促进生长发育,达到高产目的.

Physiological characteristics of nitrogen nutrition and stress-resistance of film-mulched rice in various ecological regions of Zhejiang Province

The study showed that different ecological environment and cultivation system in various ecological regions of Zhejiang Province resulted in some different physiological characteristics of nitrogen nutrition and stress-resistance,especially in the aspect of NO_3--N and NH_4 -N concentrations,between film-mulched and conventional flooded rice.Owing to the heat stress in Hangjiahu plain,the NO_3--N concentration of film-mulched rice decreased to some extent,but NH_4 -N concentration increased markedly at tillering,jointing and booting stages,compared to conventional flooded rice.In Jinqu basin,the NO_3--N concentration of film-mulched rice at booting stage was higher,while the NH_4 -N concentration in its roots was notably lower than those of conventional flooded rice,with NH_4 -N concentration in its basal stems and leaves somewhat increased.Generally,the glutamine synthetase(GS) and nitrate reductase (NR) activities in film-mulched rice leaves were enhanced at booting stage,while malondiadehyde (MDA),soluble sugar (SS) and proline(Pro) concentrations had little changes.In conclusion,film-mulched cultivation was beneficial to the rice growth and its high yielding.