通过盆栽试验,探讨核桃(Juglans regia)凋落叶在土壤中分解对受体植物菠菜(Spinacia oleracea)生长、光合生理及抗性生理的影响.试验设置A1(30 g?盆)、A2(60 g?盆)、A3(90 g?盆)3个凋落叶施用水平,对照(CK)不添加凋落叶.结果表明:(1)凋落叶分解到75 d时,菠菜株高、主根长、地上、地下生物量均随凋落叶添加量的增大而呈显著的下降趋势,分解到95-115 d时,各形态指标受到的抑制作用减弱,135 d时凋落叶的进一步分解对菠菜生长产生了促进作用;(2)在分解的前115 d,各凋落叶处理的叶绿素和类胡萝卜素含量均低于CK,且以75 d时表现得最为明显,而分解到135 d时各凋落叶处理的光合色素含量均显著高于CK;(3)经凋落叶处理的菠菜叶片净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)均显著低于CK,胞间CO2浓度(Ci)仅在A1处理下低于CK,在A2和A3处理下均高于CK;(4)菠菜叶片中超氧化物歧化酶(SOD)活性、过氧化物酶(POD)和过氧化氢酶(CAT)活性在凋落叶处理下先被诱导上升(75 d),之后又受到明显的抑制作用(95-115 d),到135 d时再次明显地高于CK;而丙二醛(MDA)含量在75 d时与CK差异不显著,95 d时随着凋落叶量的增加呈显著上升趋势,115 d时这种趋势有所减弱,到135 d时几乎回复到正常状态.综合各项指标可见,核桃凋落叶在分解初期(75 d)对菠菜产生了强烈的化感作用,主要通过氧化损伤、抑制叶绿素合成、降低其光合能力而妨碍其生长,之后随着凋落叶的进一步分解,释放的化感物质越来越少而营养物质逐渐增多,对菠菜生长的抑制作用减弱以至转变为促进作用.图1表3参33 Pot experiments were conducted to investigate the effects of litter decomposition of Juglans regia in the soil on the growth, photosynthetic physiology and physiological resistance of Spinachia oleracea, a pot experiment with A1 (30 g 盆 pot), A2 (60 g The results showed that: (1) When the litter leaves were decomposed to 75 d, the plant height, main root length, above-ground, dry weight of spinach, The underground biomass decreased with the increasing of the amount of litter decayed. When decomposed to 95-115 d, the inhibition of each morphological index was weakened. Further decomposition of litter on 135 d promoted the growth of spinach (2) The contents of chlorophyll and carotenoid in leaves of litter below litter before 115 days of decomposition were all lower than that of CK, and the contents of chlorophyll and carotenoid were the most obvious at 75 days, (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of spinach leaves treated with litter were significantly lower than those of CK and intercellular CO2 (Ci) Only lower than CK under A1 treatment and higher than CK under A2 and A3 treatments. (4) Superoxide dismutase (SOD) activity in spinach leaves, The activities of peroxidase (POD) and catalase (CAT) were induced to rise first (75 days) after litter leaf treatment and then significantly inhibited (95-115 days), and again to 135 days While the content of malondialdehyde (MDA) was not significantly different from that of CK at 75 d, and increased significantly with the increase of litter size at 95 d. The trend was weaker at 115 d d, it almost returned to normal state.According to all the indicators, the walnut litter leaf had a strong allelopathic effect on spinach in the early stage of decomposition (75 d), which hindered the growth of spinach mainly through its oxidative damage, inhibition of chlorophyll synthesis and decrease of its photosynthetic capacity Growth, and then with the further decomposition of litter leaves, the release of allelochemical less and less nutrients gradually increased, the inhibitory effect of spinach growth weakened and even changed to promote the role of Figure 1 Table 3 Reference 33