核桃根、茎、叶提取物对蚕豆的遗传毒性分析

Genetic toxicity of active ingredients extracted from roots,stems,and leaves of walnut on Vicia faba

【目的】研究核桃根、茎、叶不同提取物的化感作用机制,为开发新型无公害植物源除草剂提供科学依据。【方法】采用蚕豆根生长试验和蚕豆微核试验,测定核桃根、茎、叶不同提取物对蚕豆生长的影响和遗传毒性。【结果】经核桃根、叶正丁醇提取物培养24和48h的蚕豆根生长减慢,当核桃根、叶正丁醇提取物浓度大于0.050g/mL时,培养72h的蚕豆根生长停滞。微核试验结果,核桃根、叶正丁醇提取物能抑制蚕豆根尖细胞生长,损伤其遗传物质,导致其有丝分裂指数下降、微核率增高,与对照相比呈显著性差异(P<0.05),且在试验浓度范围内(0.025～0.100g/mL)表现出显著的浓度效应和时间效应。【结论】核桃根和叶中含有一定遗传毒性的化感物质,能够抑制植物细胞分裂,导致细胞遗传物质损伤,对周围植物产生不可逆的遗传损伤效应。

Objective In order to provide scientific evidences for the development of pollution-free botanical herbicides,this study explored the allelopathic mechanism of different extracts from the roots,stems,and leaves of walnut（Juglans regia L.）.Method The Vicia faba root growth test and micronucleus test were used to study the effects of the different ingredients derived from the roots,stems,and leaves of walnut on Vicia faba growth and their genetic toxicity.Result The research results showed that the Vicia faba root grew slowly after being cultured by the n-butanol extracts（0.025,0.050,0.100 g/mL） from walnut roots and leaves for 24 and 48 hrs,respectively.When the extracts concentration was greater than 0.050 g/mL,the Vicia faba root,which was cultured for 72 hrs,stopped growing.The micronuclear test indicated that the n-butanol extracts of roots and leaves could inhibit the growth of Vicia faba root tip cells and damage the genetic material,which resulted in the mitotic index of Vicia faba root tips to decrease and micronuclear rate to increase.The experimental group＇s research results had significant difference compared with the controlled group＇s research results（P0.05） and the concentration and time effects in the experimental concentration range（0.025-0.100 g/mL） was significant.Conclusion The walnut roots and leaves had allelochemicals genetic toxicity,which inhibited the division of plant cells and damaged the genetic materials of cells;this resulted in the irreversible genetic damage to the nearby plants.