Xia Qing-ping, Gao Hong-bo, Li Jing-rui
College of Horticulture, Agricultural University of Hebei, Baoding 071000, Hebei, China.
Ying Yong Sheng Tai Xue Bao. 2011 Apr;22(4):999-1006.
By the method of hydroponic culture, this paper studied the effects of exogenous gamma-aminobutyric acid (GABA) on the photosynthetic pigment contents, photosynthesis, and chlorophyll fluorescence parameters of muskmelon seedlings under hypoxia stress. Hypoxia stress induced a significant decrease of photosynthetic pigment contents, resulting in the decrease of photosynthesis. Applying GABA could significantly increase the photosynthetic pigment contents, net photosynthetic rate (P(n)), stomatal conductance (G(s)), intercellular CO2 concentration (C(i)), carboxylation efficiency (CE), maximal photochemical efficiency of PS II (F(v)/F(m)), photochemical quenching (q(P)), apparent photosynthetic electron transfer rate (ETR), and quantum yield of PS II electron transport (phi(PS II)), and decrease the stomatal limitation value (L(s)), minimal fluorescence (F(o)), and non-photochemical quenching (NPQ) under both hypoxic and normal conditions. The alleviation effect of GABA on photosynthetic characteristics was more obvious under hypoxia stress. However, simultaneously applying GABA and VGB could significantly decrease the alleviation effect of GABA under hypoxia stress.
采用水培法,研究了外源γ-氨基丁酸(GABA)对低氧胁迫下甜瓜幼苗光合色素含量、光合作用及叶绿素荧光参数的影响。低氧胁迫导致光合色素含量显著降低,进而引起光合作用下降。施加GABA可显著提高低氧和正常条件下的光合色素含量、净光合速率(P(n))、气孔导度(G(s))、胞间CO2浓度(C(i))、羧化效率(CE)、PS II最大光化学效率(F(v)/F(m))、光化学猝灭(q(P))、表观光合电子传递速率(ETR)以及PS II电子传递量子产额(phi(PS II)),并降低气孔限制值(L(s))、最小荧光(F(o))和非光化学猝灭(NPQ)。在低氧胁迫下,GABA对光合特性的缓解作用更为明显。然而,同时施加GABA和VGB可显著降低低氧胁迫下GABA的缓解效果。