不同耐渍基因型芝麻在厌氧胁迫下根系的生理与结构变化  

Physiological and Structural Adaptation in Roots of Genotypes with Different Tolerance to Waterlogging in Sesame(Sesamum indicum L.)Under Anoxia Stress

作　　者：王文泉[1,2] 郑永战[3] 梅鸿献[3] 张福锁[1] 

机构地区：[1]中国农业大学植物营养系 [2]热带作物生物技术国家重点实验室,海口571101 [3]河南省农业科学院棉花油料作物研究所

出　　处：《植物遗传资源学报》2003年第3期214-219,共6页Journal of Plant Genetic Resources

基　　金：国家重点基础研究发展规划项目 (G19990 1170 7)资助

摘　　要：利用 4种耐渍性不同的芝麻基因型 ,在厌氧胁迫条件下检测了根部无氧呼吸酶活性、内源乙烯含量并调查了根形态和解剖结构 ,以比较研究旱生植物耐渍性的主要机制。同时设计了田间分期多次淹水试验 ,观察早期淹水训练对芝麻生长和产量的影响。结果表明 :耐渍种质的乙烯释放量在根中增加了 6 0 6倍 ,茎中 1 76倍 ,不定根数量增加了 4 0～ 5 0倍 ,在初生根和不定根皮层形成典型的通气组织。非耐渍种质中未检测到乙烯变化 ,不定根数量增加了 0 79～ 1 8倍 ,根中无明显的通气组织发生 ,但是乙醇脱氢酶 (ADH)活性可增加 4 2～ 9 3倍 ,高于耐渍种质。分期淹水试验以四对真叶期和初花期处理产量较高 ,与对照无显著差异 ,而终花期一次性淹水产量损失最大。综合分析认为 ,不定根增生和根皮层通气组织的形成是芝麻耐渍性的重要机制 ,根中内源乙烯的增加与结构适应变异有关。淹水训练能够有效地改善芝麻品种耐渍能力为结构适应提供了进一步的证据。For understanding the main mechanism of waterlogging tolerance in terrestrial species, the activity of anoxia respiration enzyme, endogenous ethylene content in roots, morphological change and anatomical structure of roots were investigated under anaerobic condition utilizing four sesame genotypes with different flooding resistance. And a field multi-time flooding test was designed for analyzing the effects of early flooding on growth and yield of these sesame lines. To waterlogging tolerante germplasm, ethylene content increased 6.06 folds in roots and 1.76 folds in stem, number of adventitious roots developed to 4.4～5.0 times and there was impressive aerenchyma formed in primary and adventitious root cortex. To intolerant varieties, there was none ethylene content change observed, number of adventitious roots only increased 0.79～1.8 times and the formation of aerenchyma in root cortex could not found, but the activity of alcohol dehydrogenase (ADH) could rise 4.2～9.3 folds that were much higher to increase of ADH in tolerant lines. In the multi-time flooding test, four-leaf stage treatment and flowering stage treatment had higher seed yields but with no significant difference from the check, and the end-flowering stage treatment had the lowest yield. It is concluded that the development of adventitious root and the formation of aerenchyma in root cortex can be an important mechanism of adaptation to flooding in sesame and probably this occurs due to increase of endogenous ethylene content. The fact that pre-flooding acclimation could effectively improve waterlogging tolerance of sesame provides clues to the structure adaptation.

关 键 词：耐渍基因型 芝麻 厌氧胁迫 根系 生理 结构 

分 类 号：S565.3[农业科学—作物学]