紫茎泽兰气态挥发物对云南松种子萌发及幼苗生长的化感作用

为了解紫茎泽兰气态挥发物的化感作用,在透明密闭保鲜盒内用其不同质量新鲜茎叶对云南松种子进行处理,质量浓度分别为高质量浓度(0.069 4 g/cm3)、中等质量浓度(0.023 1 g/cm3)和较低质量浓度(0.007 7 g/cm3)。结果表明:气态挥发物对云南松种子发芽过程有明显影响,随着处理质量浓度的提高,开始发芽的天数、达到发芽高峰的天数推迟,达到发芽高峰当天发芽数下降,发芽数开始明显下降的天数延迟,过程曲线图由急升急降逐渐变缓,到高质量浓度时几乎成一条直线。气态挥发物对云南松种子萌发(发芽率、发芽势、发芽速率)和幼苗生长(鲜质量、干质量、胚根长、胚轴长)的效应趋势基本相同,呈现出高质量浓度抑制作用强烈,随质量浓度降低,抑制作用减弱的规律。林下紫茎泽兰的广泛分布,可能通过化感作用影响云南松的天然更新和生长。

Allelopathic Effect of Volatiles of Eupatorium adenophorum on Seed Germination and Seedling Growth of Pinus Yunanensis

In order to know the allelopathy of stem and leave volatiles of Eupatorium adenophorum,Pinus yunnanensis seeds were treated by fresh stem and leave of E.adenophorum of different quality in transparent airtight boxes,the concentrations are high concentration(0.069 4 g/cm3),middle concentration(0.023 1 g/cm3)and lower concentration(0.007 7 g/cm3) respectively.The results showed that the volatiles had a significant influence on seed germination process of P.yunnanensis,the day on which seeds started to germinate,the day on which germination pinnacle came,the day on which germination number descended significantly,all delayed with the increase of concentrations,seed germination numbers of the day at the germination pinnacle also delayed with the increase of concentrations,so the germination process curves became gentle with the increase of concentrations,and nearly became a beeline at high concentration.The tendency of the effects of the volatiles on seed germination(seed germination rate,seed germination potential,seed germination speed) and seedling growth(fresh weight,dry weight,radicle length,hypocotyl length)of P.yunnanensis was similar,showing a rule that high concentration had a negative effect on seed germination and seedling growth,the negative effect became weaker and weaker with the descent of concentrations.E.adenophorum was widely distributed on the ground under P.yunnanensis forest,and might influence natural regeneration and growth of P.yunnanensis by allelopathy.