Carbon dioxide enrichment alleviates heat stress by improving cellular redox homeostasis through an ABA-independent process in tomato plants
Carbon dioxide enrichment alleviates heat stress by improving cellular redox homeostasis through an ABA-independent process in tomato plants
复制标题
二氧化碳富集通过番茄植株中不依赖 ABA 的过程改善细胞氧化还原稳态来缓解热应激。
DOI：
10.1111/plb.12211
复制
发表时间：
2015-01-01
期刊：
影响因子：
3.9
通讯作者：
Shi, K.
中科院分区：
文献类型：
--
作者：
Li, X.;Ahammed, G. J.;Shi, K.
植物对CO2浓度升高和高温的反应是通过一个复杂的植物激素和氧化还原平衡网络来调节的。然而，脱落酸（阿坝）参与植物适应高温胁迫下的CO2浓度升高的条件还没有得到彻底的研究。研究了CO_2浓度升高（800 μ mol·cm ~（-1））和热胁迫（42 ℃，24 h）对两种不同基因型番茄内源阿坝水平和细胞氧化还原状态的影响。热胁迫显著降低了两种基因型的PSII最大光化学效率（Fv/Fm）和叶水势，但也增加了丙二醛（MDA）和电解质渗漏（EL）的水平。热诱导的损害是更严重的ABA-缺陷突变notabilis（不）比在其亲本品种艾尔莎克雷格（艾尔莎），这表明，需要一定水平的内源阿坝，以尽量减少热诱导的氧化损伤的光合机构。无论基因型如何，CO2浓度升高都能显著提高热胁迫下植株的Fv/Fm、MDA和EL值，使其耐受性增强。此外，CO2浓度升高显着加强了热应激番茄幼苗的抗氧化能力，在较长的一段时间内减少细胞的氧化还原状态，从而减轻氧化应激。然而，CO2浓度升高和热胁迫并没有改变内源阿坝水平或其生物合成基因NCED 2在任一基因型中的表达，表明阿坝不参与CO2浓度升高诱导的热胁迫缓解。这项研究的结果表明，CO2浓度升高缓解热胁迫，通过有效地调节细胞的氧化还原平衡在ABA-独立的方式在番茄植物。
Plant responses to elevated CO2 and high temperature are critically regulated through a complex network of phytohormones and redox homeostasis. However, the involvement of abscisic acid (ABA) in plant adaptation to heat stress under elevated CO2 conditions has not been thoroughly studied. This study investigated the interactive effects of elevated CO2 (800 mu mol center dot mol(-1)) and heat stress (42 degrees C for 24h) on the endogenous level of ABA and the cellular redox state of two genotypes of tomato with different ABA biosynthesis capacities. Heat stress significantly decreased maximum photochemical efficiency of PSII (Fv/Fm) and leaf water potential, but also increased levels of malondialdehyde (MDA) and electrolyte leakage (EL) in both genotypes. Heat-induced damage was more severe in the ABA-deficient mutant notabilis (not) than in its parental cultivar Ailsa Craig (Ailsa), suggesting that a certain level of endogenous ABA is required to minimise the heat-induced oxidative damage to the photosynthetic apparatus. Irrespective of genotype, the enrichment of CO2 remarkably stimulated Fv/Fm, MDA and EL in heat-stressed plants towards enhanced tolerance. In addition, elevated CO2 significantly strengthened the antioxidant capacity of heat-stressed tomato seedlings towards a reduced cellular redox state for a prolonged period, thereby mitigating oxidative stress. However, elevated CO2 and heat stress did not alter the endogenous level of ABA or the expression of its biosynthetic gene NCED2 in either genotype, indicating that ABA is not involved in elevated CO2-induced heat stress alleviation. The results of this study suggest that elevated CO2 alleviated heat stress through efficient regulation of the cellular redox poise in an ABA-independent manner in tomato plants.