作物学报2008，Vol.34Issue(9)：1615-1622,8.
水稻及其敏感突变体苯达松抗性的生理生化差异研究
Physiological Research on the Difference of Bentazon Tolerance in Wild Type Rice and Sensitive Lethal Mutants
摘要
Abstract
Bentazon sensitive lethal (bsl) mutants can be applied in hybrid rice (Oryza sativa L.) breeding for improving seed production and quality. This study was to elucidate the physiological mechanism of bentazon tolerance in rice. Tolerant rice varie-ties (W6154s and Norin 8) as well as their corresponding mutants, sensitive to bentazon, were employed in this study. Plant net photosynthetic rate (Pn), chlorophyll fluorescence, and the level of superoxide radical ( O2- ) as well as the contents of chlorophyll (Chl) and malondialdehyde (MDA), were analyzed for both tolerant and sensitive rice plants treated with bentazon. After treat-ment, the two sensitive mutants showed a significant reduction in Pn at 0.5 h. A continuous decrease of Chl contents was found over the first 3 d whereas a significant increase of MDA contents was noticed on the 3rd day and thereafter. Analysis of chloro-phyll fluorescence revealed a bentazon-induced increase in the proportion of the reduced state of QA. In the early stage after bentazon treatment, wild types and their mutants showed no significant difference in the alteration of Pn and chlorophyll fluorescence. While these two parameters then increased progressively in both wild types and remained low in the mutants. A significant gen-eration of O2- was found over the 5 d period in the mutants. Both wild types and mutants contained the same level of bentazon after 2 h of treatment. Bentazon content dropped to barely detectable amount in the wild type varieties at 1 d. However, the mu-tants retained a substantial amount of the herbicide after 5 d. It is proposed that the herbicide might inhibit rice photophythesis and accumulation of oxidative stress with the treatment of bentazon in both lethal mutants. The damaging effect on PS Ⅱ system can be significantly alleviated in the wild type varieties due to a higher rate of catabolism of the herbicide.关键词
水稻/苯达松/敏感致死突变体/抗性/生理Key words
Oryza sativa/Bentazon/Sensitive lethal mutant/Tolerance, Physiological research分类
农业科技引用本文复制引用
王云生,陆徐忠,孙明娜,宋丰顺,李莉,高同春,杨剑波..水稻及其敏感突变体苯达松抗性的生理生化差异研究[J].作物学报,2008,34(9):1615-1622,8.基金项目
The Anhui Provincial Key Science and Technology Project of China 06003010B) （）
the Nature Science Foundation of Anhui Provincial Education Department, China (2005KJI69) （2005KJI69）
