Effects of exogenous application of abscisic acid on membrane stability, osmotic adjustment, photosynthesis and hormonal status of two lucerne (Medicago sativa L.) genotypes under high temperature stress and drought stress
Effects of exogenous application of abscisic acid on membrane stability, osmotic adjustment, photosynthesis and hormonal status of two lucerne (Medicago sativa L.) genotypes under high temperature stress and drought stress
复制标题
外源脱落酸对高温和干旱胁迫下两种苜蓿基因型膜稳定性、渗透调节、光合作用和激素状态的影响
DOI：
10.1071/cp13162
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发表时间：
2014-01-01
影响因子：
1.9
通讯作者：
Liang, Jinfeng
中科院分区：
文献类型：
--
作者：
An, Yuan;Zhou, Peng;Liang, Jinfeng
抽象的。研究了高温、干旱和外源脱落酸(ABA)对两种紫花苜蓿(紫花苜蓿、紫花苜蓿)质膜稳定性、渗透调节、光合作用和激素状态的影响。耐热性比较：美国801S(耐热性)和敖汉(热敏性)，结果表明，在水分充足的条件下，在72 h的热胁迫条件下，AS801的电解质渗漏率低于敖汉，而叶绿素含量、净光合速率、气孔导度、脯氨酸含量、脱落酸含量和玉米素核苷(ZR)含量均高于敖汉。但在干旱条件下，两个品种间只有根中的Pro和ZR含量、叶和根的电解质渗漏率、净光合速率和ABA含量存在显著差异。在两种水分条件下，叶面喷施ABA显著降低了两种类型植物的电解质渗漏和气孔导度，促进了叶片水势和生长的恢复。测得的其他生理反应在干旱或水分充足的情况下有所不同，似乎是特定于基因型的。这些结果表明，不同土壤水分条件下，热敏和耐热紫花苜蓿对高温胁迫的生理反应是不同的。在不同土壤水分条件下，根中的脯氨酸积累、叶片和根中的电解质渗漏以及光合作用速率的变化可作为评价不同紫花苜蓿品种耐热胁迫能力的早期瞬时胁迫指标。
Abstract. This study was designed to examine effects of high temperature, drought and exogenous abscisic acid (ABA) on membrane stability, osmotic adjustment, photosynthesis and the hormone status of two lucerne (alfalfa, Medicago sativa L.) genotypes contrasting in heat tolerance: Ameristand 801S (AS801) (heat-tolerant), and Aohan (heat-sensitive), The results showed that AS801 had lower electrolyte leakage, but higher chlorophyll content, net photosynthetic rate, stomatal conductance, proline content, ABA content and zeatin riboside (ZR) content than Aohan during 72 h of heat stress under well-watered conditions. Under drought conditions, however, only proline content and ZR content in roots, electrolyte leakage in leaves and roots, net photosynthetic rate, and ABA content were significantly different between the two genotypes. A foliar application of ABA to heat-stressed plants significantly decreased electrolyte leakage and stomatal conductance, and increased recovery in growth and leaf water potential in the two genotypes under both watering conditions. The other physiological responses measured differed under drought or well-watered conditions, and appeared to be genotype-specific. These results suggest that the physiological responses of heat-sensitive and heat-tolerant lucerne to heat stress under different soil-water conditions varied. The heat-induced changes in proline accumulation in roots, electrolyte leakage in leaves and roots, and photosynthetic rate could serve as early instant stress indicators for evaluating the tolerance of lucerne genotypes to heat stress under different soil water conditions.