蘖穗氮肥比例对水稻叶片衰老相关化合物含量、酶活性和基因表达量的影响

摘要

This experiment,chose two different types of rice varieties to study the influence of the ratio of tiller and spike nitrogen fertilizer application on leaf senescence related compounds and enzyme activity and gene expression quantity in rice grouting maturation period,in order to provide a theoretical basis for elucidation of nitrogen nutrition on leaf senescence of the molecular regulation mechanism in rice and establish high quality and high yield cultivation techniques for rice.The results indicated that in the grouting process, leaf total nitrogen, chlorophyll a, chlorophyll b contents and SOD, POD activity in leaf and Rubisco gene transcript expression quantity gradual declined,while MDA content gradual rose. Reducing the nitrogen content of tiller fertilizer and increasing the nitrogen content of ear fertilizer could significantly increase leaf total nitrogen content and leaf chlorophyll a,chlorophyll b contents,rise SOD, POD activity in leaf and Rubisco gene transcript expression quantity, and could significantly inhibit the increase of MDA content in leaves,and attenuation rate of the nitrogen,chlorophyll content and enzyme activity, decrease Rubisco gene expression quantity decended range and prolong gene up-regulated expression time. Total nitrogen content of leaves and MDA content showed significant negative correlation, and chlorophyll a and chlorophyll b contents, SOD, POD activity and Rubisco gene trans-cript expression quantity showed significant positive correlation.%文章选用两种不同类型水稻品种研究蘖穗氮肥追施比例对水稻灌浆成熟期叶片衰老相关化合物、酶活性及基因表达量影响.结果表明,灌浆过程中叶片全氮含量和叶绿素a、b含量及叶片超氧化物歧化酶(SOD)和过氧化物酶(POD)活性、Rubisco家族基因表达量等逐渐下降,丙二醛(MDA)含量逐渐升高;减少分蘖肥施氮量和增加穗肥施氮量可显著提高灌浆各时期叶片全氮和叶绿素a、b含量及叶片SOD和POD活性、Rubisco家族基因表达量,显著抑制叶片丙二醛(MDA)含量升高和叶片氮浓度衰减速度及叶绿素和酶活性降解速度与幅度,减缓Rubisco家族基因表达量下降幅度,延长基因上调表达时间;叶片全氮含量与MDA含量间呈极显著负相关,与叶绿素a、b含量、SOD和POD活性及Rubisco家族基因转录表达量均呈极显著正相关.研究结果为水稻优质高产减肥栽培技术提供理论依据.