摘要
以萝卜和生菜为受体材料,采用培养皿生物测定法,探讨空心莲子草植株水浸提液的化感效应,同时测定相关保护酶活性变化,研究其作用机理。结果显示,空心莲子草植株水浸提液对萝卜和生菜种子发芽率表现出明显的化感抑制作用,随处理浓度增加抑制作用逐步增强。水浸提液对萝卜和生菜幼苗生长总体上表现为抑制,对胚根生长的抑制作用要明显大于胚轴。低浓度(0.01g/mL)浸提液对胚轴的生长表现出促进作用,随浓度升高这种促进作用逐步减弱,当浓度达到0.04g/mL时,胚轴生长均被明显抑制。浸提液对胚根长度和植株鲜重的抑制程度随着处理浓度升高而增强,高浓度下胚根生长几乎停滞。浸提液对保护酶活性的影响较为复杂,在低浓度条件下SOD、POD和CAT活性均不同程度的上升,随处理浓度的进一步增加SOD活性逐步下降,POD和CAT活性均表现为下降后再上升。萝卜和生菜幼苗的MDA含量随植株水浸提液处理浓度增加而持续增加,萝卜的增幅略大于生菜。
Alternanthera philoxeroides is a worldwide weed.After invasion of A.philoxeroides,the local ecosystem can be irreversibly damaged and agricultural production seriously affected.Allelopathy is an effective chemical weapon in the invasion process of exotic weeds.With radish（Raphanus sativas） and lettuce（Lactuca sativa） as receptor materials,the allelopathic effect of plant aqueous extract of A.philoxeroides was studied using a Petri dish bioassay.In this process,plant protective enzyme activity was also measured to clarify the allelopathic mechanism.Seed germination rates of lettuce and radish showed significant allelopathic inhibition which gradually increased with an increase of the A.philoxeroides plant aqueous extract concentration.This inhibition in lettuce was significantly greater than in radish.A.philoxeroides plant aqueous extracts caused a general inhibition of the radish and lettuce seedlings growth.Inhibition on radicle growth was significantly greater than on the hypocotyl.At low concentrations（0.01 g/mL）,A.philoxeroides plant aqueous extracts promoted growth of hypocotyls but as the concentration increased,this promotion gradually diminished.Radish and lettuce hypocotyl growth were significantly inhibited at a concentration of 0.04 g/mL.The degree of inhibition of radicle length and fresh weight gradually increased with increasing concentrations.The radicle growth of radish and lettuce seedlings was almost inhibited at a concentration of 0.04 g/mL.The degree of inhibition of plant fresh weight in lettuce was more serious than in radish.Changes in protective enzyme activity were more complex.Superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT） activities increased at low concentrations but as the concentration increased,SOD activity gradually decreased,while POD and CAT activities initially decreased and then increased.Malondialdehyde（MDA） content of radish and lettuce seedlings increased with increased concentrations of A.philoxeroides plant aqueous extracts and the increase rate was slightly higher in radish than in lettuce.However,the MDA content increases at low concentrations were not significant.With a concentration of 0.04 g/mL of A.philoxeroides plants aqueous extract,MDA contents in both radish and lettuce seedlings increased rapidly.Compared with the control,the increased rate of MDA content in radish and lettuce seedlings were 116.67% and 98%,respectively.
出处
《草业学报》
CSCD
北大核心
2013年第1期288-293,共6页
Acta Prataculturae Sinica
基金
国家科技支撑计划项目子课题(2007BAD07B03)
福建农林大学园艺学院青年学术骨干培养基金(FAFU2012YYPY08)
福建省自然科学基金(2011J01083)资助
关键词
空心莲子草
水浸提液
化感效应
Alternanthera philoxeroides
plant aqueous extract
allelopathy
