四种化感物质对苜蓿和菟丝子种子萌发及幼苗生长的影响

选用四种化感物质:阿魏酸、对羟基苯甲酸、肉桂酸和香豆素,分别设置浓度为50、100、200和400 mg/L的处理液.结果表明:四种化感物质不同浓度处理液对苜蓿和菟丝子种子萌发及幼苗生长均有明显的影响.在高浓度时(200、400 mg/L),四种化感物质对苜蓿和菟丝子种子的发芽指数的抑制作用强度为:香豆素>肉桂酸>阿魏酸>对羟基苯甲酸.在低浓度时肉桂酸和对羟基苯甲酸对苜蓿种子有一定的促进作用,肉桂酸和阿魏酸对菟丝子种子有一定的促进作用.四种化感物质对苜蓿和菟丝子幼苗长度的抑制作用强度为:香豆素＞肉桂酸＞对羟基苯甲酸＞阿魏酸,随着处理液浓度的增加抑制作用逐渐增强.香豆素50 mg/L处理液促进了苜蓿幼苗胚根横向生长,使幼苗鲜重显著增加.

Effects of Allelochemicals on Seed Germination and Seedling Growth of Alfalfa and Dodder

The main purpose of the experiment was conducted to study the effects of four kinds of allelochemicals(ferulic acid,p-Hydroxybenzoic acid,cinnamic acid and coumarin)on seed germination and seedling growth of alfalfa and dodder.The concentration of four allelochemicals were used in four degrees: 50,100,200 and 400 mg/L.The results showed that the four allelochemicals had significant allelopathic effects on seed germination and seedling growth,and the effects were significantly related to the allelochemicals and their concentrations.In high concentrations(200,400mg/L),the inhibition effects on seed germination index showed as follows:coumarin>cinnamic acid>ferulic acid>p-Hydroxybenzoic acid.In low concentrations,cinnamic acid,ferulic acid and p-Hydroxybenzoic acid had a certainly stimulating effect.The inhibition effects on seedling growth showed as follows:coumarin>cinnamic acid>p-Hydroxybenzoic acid>ferulic acid,the inhibition strengthened with the concentration increased.Coumarin 50 mg/L had a significant stimulating effect on fresh weight of the alfalfa for promoting the lateral growth of the radicel.