Differential Responses of Polyamines and Antioxidants to Drought in a Centipedegrass Mutant in Comparison to Its Wild Type Plants.
Differential Responses of Polyamines and Antioxidants to Drought in a Centipedegrass Mutant in Comparison to Its Wild Type Plants.
复制标题
与野生型植物相比，蜈蚣突变体中多胺和抗氧化剂对干旱的差异反应
DOI：
10.3389/fpls.2017.00792
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发表时间：
2017
影响因子：
5.6
通讯作者：
Lu S
中科院分区：
文献类型：
--
作者：
Liu M;Chen J;Guo Z;Lu S
假俭草是一种重要的暖季型草坪草，草坪养护要求低。然而，我们对假俭草对干旱胁迫的生理适应的认识有限。以假俭草22-1为材料，研究了其对干旱胁迫的生理响应，并与野生型进行了比较。与野生型相比，该突变体表现出较高的相对含水量、净光合速率（A）和气孔导度（gs），较低的离子渗漏率和丙二醛（MDA）含量。A与gs、MDA呈显著正相关。在22-1中保持了比WT植物更高水平的抗氧化酶活性、非酶抗氧化剂和多胺，包括腐胺（Put）、亚精胺（Spd）和精胺（Spm）。在干旱胁迫下，超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、谷胱甘肽还原酶（GR）活性和抗坏血酸（阿萨）含量与Put和Spd水平呈显著相关，还原型谷胱甘肽水平与Put呈显著相关。外源Put、Spd和Spm处理提高了WT植株的耐旱性和SOD、CAT、APX和GR活性。结果表明，22-1的耐旱性与其体内多胺含量和抗氧化防御系统有关，这可能有助于提高其对干旱氧化损伤的防御能力。
Centipedegrass (Eremochloa ophiuroides [Munro] Hack.) is an important warm-season turfgrass species with low turf maintenance requirements. However, our knowledge on physiological adaptation of centipedegrass to drought stress is limited. Physiological responses to drought in a gamma-ray-induced mutant 22-1 as compared with two wild type (WT) lines were analyzed for understanding of drought tolerance mechanism of centipedegrass. The mutant showed an elevated drought tolerance with higher levels of relative water content, net photosynthetic rate (A) and stomatal conductance (gs) and lower levels of ion leakage and malondialdehyde (MDA) under drought stress as compared with WT plants. A showed significant correlation with gs and MDA. Higher levels of antioxidant enzymes activities, non-enzyme antioxidants, and polyamines including putrescine (Put), spermidine (Spd), and spermine (Spm) were maintained in 22-1 than in WT plants. Superoxide dismutase (SOD), catalase (CAT), ascorbate-peroxidase (APX), and glutathione reductase (GR) activities and ascorbic acid (AsA) content were significantly correlated with both Put and Spd levels, and reduced glutathione level was correlated with Put during drought stress. Exogenous application of Put, Spd, and Spm increased drought tolerance and activities of SOD, CAT, APX, and GR in WT plants. The results suggest that higher levels of polyamines and antioxidant defense system are associated with the elevated drought tolerance in 22-1, which may improve protection on photosynthesis against drought induced oxidative damage.