遮荫处理对葛根光合及抗氧化特性的影响  

Effect of shading on photosynthetic and antioxidant characteristics of Pueraria lobata

作　　者：吴潇 何秀娟[1] 吴超[1] 董玉锋 张燕[1] 徐宇[1] 秦卫东 吕俊[1] 王三根[1] 宗学凤[1] WU Xiao;HE Xiu-juan;WU Chao;DONG Yu-feng;ZHANG Yan;XU Yu;QIN Wei-dong;LU Jun;WANG San-gen;ZONG Xue-feng(College of Agronomy and Biotechnology,Southwest University,Chongqing 400715,China;Kudzu Research Center,Fourgen Kudzu Industrial Limited,Chongqing 402385,China)

机构地区：[1]西南大学农学与生物科技学院,重庆400715 [2]富葛实业葛根研究中心,重庆402385

出　　处：《草业学报》2019年第5期68-78,共11页Acta Prataculturae Sinica

基　　金：中国111计划作物种质资源利用创新基地建设项目(104510-205001);重庆市大足区科委项目(DZKJ 2018AAA1011)资助

摘　　要：设置3个光照强度,研究葛根在引种栽培中对光环境变化的响应和适应性。结果显示,叶绿素a、叶绿素b、类胡萝卜素含量和光合色素总量随遮荫程度的增加呈上升趋势,但叶绿素a/b变化则相反;葛根净光合速率(P_n)、气孔导度(G_s)和蒸腾速率(T_r)随遮荫程度的增加呈下降趋势,而胞间CO_2浓度(C_i)则随之上升;葛根叶绿素荧光参数初始荧光(F_0)、最大荧光(F_m)、可变荧光(F_v)、光合效率潜能(F_v/F_0)、最大光化学效率(F_v/F_m)和PSⅡ实际光化学效率(Φ_(PSⅡ))均随遮荫程度的增加而升高。随遮荫程度的增加,葛根叶片可溶性糖、可溶性蛋白和游离氨基酸含量降低,而丙二醛含量和电导率上升;超氧化物歧化酶(SOD)、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)等抗氧化酶活性随遮荫程度的增加呈下降趋势。综合可见,严重遮荫在一定程度上对葛根生长造成胁迫,引种栽培中要防止光照强度过低对葛根的不利影响。Light is the main environmental factor for plants to capture energy. Severely low light conditions can reduce the photosynthetic efficiency of plants leading to limited plant growth, and excess light can also hinder plant growth and development. An experiment was undertaken to investigate changes in photosynthesis parameters and antioxidant characteristics in Pueraria lobata under different shading treatments: control (100% natural light, T 1), mild shade (75% natural light, T 2) and moderate shade (50% natural light, T 3). Seedlings of P. lobata were collected and grown in a nursery, and then healthy seedlings of uniform-size seedlings were transferred to the shade shed when seedlings had 8 or 9 leaves. Each treatment was replicated 6 times. It was found that chlorophyll a, chlorophyll b, carotenoid content and total photosynthetic pigment content were increased with the increase of shading degree, while the change of chlorophyll a/b was opposite;The net photosynthetic rate ( P n), stomatal conductance ( G s) and transpiration rate ( T r) of P. lobata decreased with increased shading, while the intercellular CO 2 concentration ( C i) was increased. The chlorophyll fluorescence parameters of minimal fluorescence ( F 0), maximal fluorescence ( F m), variable fluorescence ( F v), F v/ F 0, F v/ F m and PSII actual photochemical efficiency (Φ PSⅡ) of P. lobata were increased with increased shading. Meanwhile, soluble sugar, soluble protein, and free amino acid levels in P. lobata leaves decreased with increased shading degree, while malondialdehyde levels and electrical conductivity increased. The antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX) and glutathione reductase (GR) decreased with increased shading. The results indicate that low light levels cause stress to P. lobata and it is necessary to avoid low light stress when P. lobata seedlings are establishing. The mechanisms of shading effects on photosynthetic and antioxidant systems of

关 键 词：葛根 遮荫 弱光 叶绿素荧光特性 光合速率 生理指标 

分 类 号：S567[农业科学—中草药栽培]