沙芥不同部位水浸液自毒作用研究

Autotoxicity of Aquatic Extracts from Different Parts of Pugionium cornutum(L.)Gaertn

采用室内培养皿生物测定的方法,研究了不同浓度的沙芥叶、果皮、枝条水浸提液的自毒作用。结果表明：沙芥自毒效应的总体趋势为水浸提液浓度越高,抑制作用越强;高于0.15g/mL的浓度处理,均显著降低了沙芥种子发芽率、发芽指数、苗高、根长、幼苗鲜重及干重。在0-0.10g/mL的浓度范围内,水浸提液对沙芥种子萌发及幼苗生长抑制作用不明显。随着水浸提液浓度升高,SOD与POD酶活性降低,而CAT酶活性呈先升后降的趋势,丙二醛（MDA）含量则持续增加。不同部位水浸提液的自毒作用强弱表现为叶〉果皮〉枝条。沙芥不同部位自毒作用是沙芥连作障碍的重要因素。

The autotoxicity of different concentrations of aqueous extracts from stems,leaves and peels of Pugionium cornutum was studied by means of bioassay in laboratory.The results showed that the inhibition of plant growth enhanced as the aqueous extracts concentration increased.When the concentration of the extract was more than 0.15g/mL,it strongly decreased the germination rate,germination index,seedling height,root length,fresh weight and dry weight of Pugionium cornutum.However,when the concentration was 0-0.10g/mL,the aqueous extracts in different parts had no obvious effects on seed germination and seedling growth of Pugionium cornutum.With the concentration of aqueous extracts increasing,SOD and POD activity were significantly inhibited,CAT activity was firstly increased and then decreased,while the MAD content increased constantly.Autotoxicity of aqueous extracts in different parts was in the order of leaf〉peel〉branch.These indicated that autotoxicity of different parts of Pugionium cornutum was an important factor influencing continuous cropping obstacle.