5-Aminolevulinic acid enhances photosynthetic gas exchange, chlorophyll fluorescence and antioxidant system in oilseed rape under drought stress
5-Aminolevulinic acid enhances photosynthetic gas exchange, chlorophyll fluorescence and antioxidant system in oilseed rape under drought stress
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5-氨基乙酰丙酸增强干旱胁迫下油菜光合气体交换、叶绿素荧光和抗氧化系统
DOI：
10.1007/s11738-013-1307-9
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发表时间：
2013-09-01
影响因子：
2.6
通讯作者：
Zhou, Weijun
中科院分区：
文献类型：
--
作者：
Liu, Dan;Wu, Lingtong;Zhou, Weijun
研究了在干旱胁迫和恢复条件下，叶面喷施5-氨基乙酰丙酸(ALA)对油菜叶片水分关系、气体交换、叶绿素荧光以及抗氧化酶活性和基因表达谱的影响。将四叶期幼苗置于水分充足(保水的80%)或干旱胁迫(保水的40%)条件下，然后叶面喷水或ALA(L−1)30 mg。干旱抑制了植物生物量的积累，降低了叶绿素含量和叶片水分状况(相对含水量和水势)。光系统II的实际量子效率和电子传递速率与净光合速率平行地受到阻碍。干旱胁迫诱导了丙二醛(MDA)和过氧化氢的积累，提高了过氧化氢酶(CAT)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)和超氧化物歧化酶(GR)的活性，上调了APX和GR的表达。复水4d后，干旱处理幼苗的大部分生理参数恢复到正常水平。叶面喷施ALA维持了相对较高的叶片水分状况，提高了叶片的叶绿素含量、净光合速率、光系统II的实际量子效率、光化学猝灭、非光化学猝灭和电子传递速率。外源ALA还缓解了干旱处理植株体内丙二醛和过氧化氢的积累，提高了抗氧化酶活性，增强了CAT和POD的表达。这些结果表明，ALA可以有效地保护油菜幼苗免受干旱胁迫的伤害。
This study evaluates the role of exogenous foliar application of 5-aminolevulinic acid (ALA) on water relations, gas exchange, chlorophyll fluorescence, and the activities and gene expression patterns of antioxidant enzymes in leaves of oilseed rape under drought stress and recovery conditions. Seedlings at four-leaf stage were imposed to well-watered condition (80 % of water-holding capacity) or drought stress (40 % of water-holding capacity) and subsequently foliar sprayed with water or ALA (30 mg l−1). Drought suppressed the accumulation of plant biomass and decreased chlorophyll content and leaf water status (relative water content and water potential). The actual quantum yield of photosystem II and electron transport rates were hampered in parallel to net photosynthetic rate. However, drought stress induced the accumulation of malondialdehyde (MDA) and hydrogen peroxide, enhanced the activities of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR) and superoxide dismutase and up-regulated the expression ofAPXandGR. After rehydration for 4 days, the growth of drought-treated seedlings was restored to normal level for most of the physiological parameters. Foliar application of ALA maintained relatively higher leaf water status and enhanced chlorophyll content, net photosynthetic rate, actual quantum yield of photosystem II, photochemical quenching, non-photochemical quenching and electron transport rates in stressed leaves. Exogenous ALA also alleviated the accumulation of MDA and hydrogen peroxide, increased the activities of antioxidant enzymes and enhanced the expression ofCATandPODin drought-treated plants. These results indicate that ALA may effectively protect rapeseed seedlings from damage induced by drought stress.