毛白杨根系化感作用

Preliminary Study of Allelopathy of Root Aqueous Extracts from Populus tomentosa

以杨—农复合经营中的3种主要间作物(紫花苜蓿、萝卜、小麦)及杨树种子为受体,研究8年生、45年生毛白杨根系水浸提液(0.001、0.020、0.050、0.100 g·mL-1)对4种受体种子萌发和幼苗生长的影响。结果表明,8年生和45年生毛白杨根系水浸提液在0.050、0.100 g·mL-1时,显著抑制4种受体种子的萌发(小麦发芽率除外)和幼苗的生长(杨树苗高生长除外),且随浓度的降低,抑制作用逐渐减小,低浓度时有时抑制作用不显著,甚至有促进作用。紫花苜蓿和萝卜种子的发芽率和发芽指数对毛白杨化感作用更敏感;小麦幼苗的高生长、杨树幼苗根生长对毛白杨化感作用更敏感。另外,8年生毛白杨根系水浸提液对4种受体种子萌发和幼苗生长的抑制作用强于45年生毛白杨,且差异显著。

We adopted root aqueous extracts from Populus tomentosa of different age （8 years and 45years） at different concentrations （0.001,0.020,0.050 and 0.100 g· mL^-1 ） to deal with the seed germination and seedling growth of three common agronomic crops （Wheat,Alfalfa,Radish ） and Poplar.The results showed that the root aqueous extracts of P.tomentosa of both 8 years and 45 years had negative effects on seeds germination ,seedlings and roots growth of Wheat ,Alfalfa,Radish and poplar at higher concentration （0.050 and 0.100 g· mL^-1）,and the inhibited effects decreased gradually with decreasing concentration of root aqueous ex -tract.Occasionally their effects were not significant at lower concentration and even the root aqueous extracts increased seed germina -tion and seedling growth.However ,the root aqueous extract of 45 years had positive effects on the seedling growth of poplar ,and had no effects on the seed germination of Wheat.Variables related to seed germination were more susceptible for Alfalfa ,Radish than for Wheat and Poplar ,while seeding height-related variables more susceptible for Wheat than others , and root height-related variables more susceptible for Poplar.In general ,the inhibited effects of root aqueous extracts of 8 years on both seeds germination and seed-lings growth of plants tested were more intensive than root aqueous extracts of 45 years.The effects of different age root aqueous ex-tracts on seeds germination and seedlings growth of Wheat and Poplar were significantly different ,as well as on seeds germination of Alfalfa.