内源CTK和IAA平衡对水稻分蘖芽休眠与萌发的影响.pdf

内源CTK 和IAA 平衡对水稻分蘖芽休眠与萌发的影响 罗宝杰** 许俊旭** 丁艳锋 李刚华 刘正辉 王绍华* 南京农业大学农学院 / 农业部南方作物生理生态重点开放实验室，江苏南京 210095 摘 要：研究水稻抽穗期分蘖休眠与萌发转换过程中CTK 和IAA 含量及CTK/IAA 值的变化，探讨内源激素平衡对水 稻分蘖的调控作用。采用外施6-BA 打破分蘖芽休眠和去穗后外施IAA 抑制分蘖芽萌发两种处理，创建分蘖芽休眠与 萌发转换的材料，测定伸长节和伸长节分蘖芽中CTK 和IAA 的含量。6-BA 处理打破了分蘖芽的休眠，显著提高了倒 二节和倒二芽中CTK 含量，降低了倒二节中IAA 含量，对倒二芽中IAA 含量影响不大，显著提高了节、芽中CTK/IAA 值。去穗后外施IAA 逆转了去穗对节、芽CTK 含量提高效果，CTK 含量维持在较低值，显著提高了倒二节中IAA 含 量，对倒二芽中IAA 含量无显著影响，显著降低了节、芽中CTK/IAA 值。CTK 和IAA 共同调控分蘖发生，较高的CTK/IAA 值利于分蘖芽萌发，较低的CTK/IAA 值使其休眠，节中CTK/IAA 值在2.6~2.8 ，芽中CTK/IAA 值在4.8~5.0，可作为 分蘖芽休眠与萌发转换的临界指标。 关键词：水稻；分蘖芽；休眠与萌发；激素平衡 Effects of Endogenous Hormone Balance on Dormancy and Germination of Tiller Bud ** ** * LUO Bao-Jie , XU Jun-Xu , DING Yan-Feng, LI Gang-Hua, LIU Zheng-Hui, and WANG Shao-Hua College of Agriculture, Nanjing Agricultural University / Key Laboratory of Crop Physiology Ecology in Southern China, Ministry of Agriculture, Nanjing 210095, China Abstract: The objection of this experiment was to study the changes of contents of CTK, IAA and the ratio of CTK/IAA during heading stage , and to investigate the regulation of endogenous hormones in rice tiller. Exogenous 6-BA and IAA were used to regulate the development of tiller buds, establish the transfer between dormancy and germination, and measure the contents of CTK and IAA in elongated nodes and tiller buds located at the elongated nodes. The exogenous 6-BA Increased the CTK contents in nodes and tiller buds, decreased the IAA content in nodes had little effect in the content of IAA in tiller buds, significantly increased ratios of CTK/IAA in both nodes and tiller buds, and promoted the transfer from dormancy to germination. External IAA after removing panicle decreased CTK contents in nodes and tiller buds, which were maintaine