银木凋落叶分解对三种农作物生长及生理特性的影响-应用与环境生物.doc

3种农作物银木凋落叶的* 杨珊珊1 王 茜2 胡庭兴1 胡红玲1** 廖玉华1 陈玉凤1 谭 飞1 叶 1 1四川农业大学林学院 成都 611130 2西南大学生命科学院 重庆400715 摘 要 采用盆栽试验，探讨了银木（Cinnamomum septentrionale）凋落叶在土壤中分解初期对受体植物玉米（Zea mays）、黄瓜（Cucumis?sativus）豇豆（Vigna?unguiculata）生长及生理特性的影响试验设置3个凋落叶添加水平，即T1（25 g∕盆）、T2（50 g∕盆）T3（75 g∕盆），对照CK不添加凋落叶。结果表明：（1）银木凋落叶分解对三种农作物的叶面积和生物量积累产生显著抑制，同时显著抑制了黄瓜、豇豆的高生长。（2）T2、T3处理显著抑制了三种作物的叶绿素[Chl (a+b)]及类胡萝卜素（Car）含量，且在一定量凋落叶处理下，叶片光合色素比例有所变化，整体呈现出Chla/Chlb值上升和Chl/Car值下降的趋势。（3）玉米和豇豆的净光合速率（Pn）、气孔导度（Gs）和蒸腾速率（Tr）随着凋落叶量的加大而显著降低（P＜0.05），而胞间二氧化碳浓度（Ci）却有所上升。此外，黄瓜的光合速率及气体交换参数在银木凋落叶处理下呈下降趋势。（4）经凋落叶处理的三种作物的过氧化氢酶（CAT）、过氧化物酶（POD）和超氧化物酶（SOD）活性总体上低于CK。黄瓜、豇豆的丙二醛（MDA）含量分别在T3、T1处理下显著降低，而其余各凋落叶处理间并无显著差异。综上所述，银木凋落叶在土壤中分解释放的化感物质可能通过降低受体作物的光合作用速率及活性氧代谢能力，进而图2表3参42关键词 凋落叶；化感作用；生长；玉米；黄瓜；豇豆 S718.5 Physiological responses to allelopathy of decomposing Cinnamomum septentrionale leaf litter in seedling of three crops* YANG Shan-shan1, WANG Qian2, HU Hongling*1, HU Tingxing1, LIAO Yu-hua1, CHEN Yufeng1, TAN Fei1 YE Mao1 1Faculty of Forestry, Sichuan Agricultural University, Chengdu 611130, China 2Faculty of Life Science, Southwest University, Chongqing 400715, China Abstract Objectives: To study the effects of Cinnamomum septentrionale leaf litter decomposition on the growth of Zea mays, Cucumis?sativus and Vigna?unguiculata. Methods: A pot experiment was carried out and leaf litter was applied at rate of 0, 25, 50 and 75 gram per pot, resulting into four treatments, i. E., CK, T1, T2 and T3, respectively. Results: (1) The decomposing C. septentrionale leaf litter inhibited the height of C. sativus and V. unguiculata apparently, and showed a significant inhibitory effect on the leaf area and fresh biomass of three recipient crops. (2) The Chl (chlorophyll) and Car (carotenoid) contents of the recipient crops were dramatically decreased at T2 and T3 treatments, furthermore, when the amount of leaf litter reached a certain level, the ratios of Chla/b increased while the ratios of Chl/Car decreased significantly on the who