华南农区典型植物的他感作用研究

研究华南农业区典型植物的他感作用，结果表明，用萝卜作生测受体时地上部水浸出物表明有他感作用的植物有拧檬按、隆缘按、赤按、木麻黄、茶、蟛蜞菊、胜红蓟、三叶鬼针草、香芳、马唐、马占相思、马尾松、蕃茄等，但无明显他感作用的有白茅、铺地木兰、凤尾竹、大叶桉、糖蜜草。研究表明柠檬桉、蟛蜞菊、胜红蓟的地上部挥发物和地部分泌物都有他感作用。木麻黄、茶、蟛蜞菊地上部水浸出物有自毒作用，花生、大豆、绿豆发芽中分泌出的物质也有自毒作用。三叶鬼针革、胜红蓟、香芳、蟛蜞菊、柠蒙桉和木麻黄地上部水浸物他感作用强度一般随着浓度而加剧，但低浓度下常表现有促进作用。三叶鬼针草水提物及柠檬桉地上部挥发物的他感效应强度与采集前一个月降雨量呈显著负相关。木麻黄小枝他感作用物浓度与温度有交互效应。柠檬桉的水浸提物在土壤中易随水流失而挥发物却易被土壤吸附。在土壤中柠檬棕叶的他感作用效应随时间成负指数减少，蟛蜞菊在土壤分解后的残留率与残留物的他感效应指数绝对值显著正相关。他感成份的分离鉴定结果表明，茶叶他感作用的主要成份为茶多酚与咖啡因，木麻黄小枝他感物中分离出五种黄酮类化合物和一种阿魏酸，胜红蓟地上部分离出胜红蓟素和一种豆甾醇。

Allelopathy of Typical Plants in Agroecosystemof South China

Research showed that allelopathic effects exist in leaf leachates of Eucalyptus citriodora,E. camaldulensis,E.exserta,Casuarina equisetifolia Forst,Camellia sinesis,Wedelia chinensis,Ageratumconyzoides L.,Bodens Pilosa,Cymbopagon cilratus,Digitaric perlenuis,Pinus massoniana,Lycopersiconescutentum,but do not exist in leaf leachates of Imperata eylindrica,Indigotera endecaphylla,Bambnsamultiplex,E.robusta,Melinis minutifiora.Allelupathic effects also exist in volatiles and root exudateaof E.citriodera,W.chinensis,A.conyzoides.Autotoxicity exists in C.equisetifolia,C.sinesis,Araehishypogoea,Glycine max,and Phoseolus aureus.In seneral,inhibitive effect increases when concentra-tion of leachates increases. However,there are possitive effects when leachates of B.pilosa,A.conyzoides,C.sitratus,W.chinensis and E.citrodora are in low concentration.There are significant negative coirelation between rainfall and allelopathic effeasts of B.pi-bo and E. citratus.Thereare cross erfect between loxchates concentration of C.equiselifolia andtemperature for seed germinatiou.Lcachate of E.cilratus in soil is easier to be washed away bywater than essetial oil of E.cviraltis.The allelopthic effects decreased in type of negative exponentwhen leave of E.citratus deconiapeil in soil. Allelotvthic effect of deconiposed W.chinensis residueis significantly correlated with the reniained weisht of W.chinensis.Theine and tea polyhydric phe-nol are important components of allelopathie effect of C. sinesis.There are six chemicals indentifi-ed from C.equisetifolia and,two chemicals identified from A.conyzoides