摘要
采用盆栽试验,研究了核桃(Juglans regia)凋落叶在土壤中分解对3种受体作物萝卜(Raphanus sativus)、芥菜(Brassica juncea)和白菜(Brasicca pekinensis)生长、光合及抗性生理特性的影响,并比较不同受体作物对核桃凋落叶化感作用的敏感性,筛选可能与核桃套作的作物。试验设置4.5(T1)、9.0(T2)和18.0 g·盆-1(T3)3个凋落叶添加水平,对照(CK)不添加凋落叶。结果表明:(1)核桃凋落叶在其分解过程中对3种受体作物各项生长指标均表现出抑制作用,随着凋落叶量的增加抑制效应逐渐增强,而随着分解时间的延长抑制效应呈减弱趋势;(2)凋落叶分解80 d时,各处理3种受体作物叶片中的叶绿素和类胡萝卜素含量明显低于CK。各植物叶片净光合速率、气孔导度和蒸腾速率均显著低于CK;(3)与CK相比,各凋落叶处理3种受体作物叶片丙二醛含量增加,过氧化物酶和过氧化氢酶活性表现为受抑制作用,而超氧化物歧化酶活性表现为促进作用,可溶性糖含量增加,可溶性蛋白含量降低;(4)3种受体作物对核桃凋落叶化感综合抑制作用的敏感程度由大到小依次为白菜、萝卜和芥菜。综合各项指标可见,核桃凋落叶在分解初期(约80 d时)对3种受体作物产生了强烈的化感作用,主要通过氧化损伤、抑制叶绿素合成和降低其光合能力来阻碍其生长,之后随着凋落叶的进一步分解,释放的化感物质越来越少,对3种受体作物生长的抑制作用减弱。
A pot experiment was conducted to study effects of decomposing walnut leaf litter on growth, photosynthesis and resistant physiology of three recipient crops, i.e. radish (Raphanus sativus), mustard (Brassica juncea) and Chinese cabbage (Brasicca pekinensis) , and to compare the three crops in sensibility to allelopathy of the litter, with a view to choosing a crop suitable for interplantation with walnut trees so that ideal income can be obtained. The experiment was designed to have four litter application rates, i. e. Treatment T1 (4. 5 g . pot-1 ), Treatment T2 (9. 0 g . pot-1 ), Treatment T3 (18.0 g .pot-1) and CK (0 g. pot-1). Results show that: (1) The litter during its decomposing process displayed inhibiting effect on all the growth-related indices of the three recipient plants, and the effect increased with rising litter application rate, but declined with the decomposition process going on; (2) On D80 (80 days after application of the litter), it was found that the contents of chlorophyll and carotenoid of the recipient crops in the treatments were significantly lower than their respective ones in CK, and so were the net photosynthetic rates (Pn), stomatal conductances (Gs) and transpiration rates (Rt ) of the recipient plants ; (3) The content of MDA in leaves of the recipient plants were higher in the treatments than in CK (P〈0.05). The activities of peroxidase (POD) and catalase (CAT) were inhibited in all the treatments, while the activity of superoxide dismutase (SOD) was promoted. The content of soluble sugar (SS) increased, but the content of soluble protein (SP) decreased; and (4) The three recipient plants displayed an order of cabbage 〉 radish 〉 mustard in terms of sensitivity to the allelopathic inhibition of decomposing walnut leaf litter. Comprehensive analysis of all the indices shows that during the initial period of decomposition (about 80 days), the litter displayed strong allelopathic effects on all the three recipient plants. Growth of the recipient crops was inhibited by the litter through oxidative damage, and hinderance of synthesis and photosynthesis of chlorophyll, but with the decomposition going on, the litter released less allelopathic substances and as a result, the inhibitive effect of the litter weakened.
出处
《生态与农村环境学报》
CAS
CSCD
北大核心
2016年第4期595-602,共8页
Journal of Ecology and Rural Environment
基金
"十二五"国家科技支撑计划(2011BAC09B05)
四川省教育厅重点项目(13ZA0246)
关键词
核桃
凋落叶
化感
受体作物
光合特性
抗性生理
walnut
leaf litter
allelopathy
recipient plant
photosynthetic characteristic
resistant physiology