摘要
化感作用是外来植物成功入侵和快速扩散的机制之一,为了探讨入侵植物三叶鬼针草(Bidens pilosa L.)的化感作用机制,运用蚕豆根尖微核技术和植物切片技术,研究了不同质量浓度的三叶鬼针草水浸提液对蚕豆(Vicia faba L.)根尖细胞的遗传损伤和对根生长的影响。结果表明,三叶鬼针草水浸提液对蚕豆根尖细胞有丝分裂及生长产生不同程度的抑制和损伤,具有明显的遗传毒性。水浸提液对蚕豆根尖的影响存在显著的时间效应和质量浓度效应。经切片测量统计,水浸提液促进了成熟区细胞平周分裂,使根尖细胞层数增加;同时显著地抑制了细胞伸长,使根尖缩短,整体表现为使根尖加粗变短。三叶鬼针草水浸提液抑制了细胞有丝分裂的正常进行,并随着水浸提液质量分数的升高,分裂期细胞数目下降,微核率逐渐升高。本研究结果表明三叶鬼针草水溶性化感物质对植物的遗传稳定性及细胞形态结构具有一定的影响,三叶鬼针草的化感作用可能是其成功入侵的机制之一。
Allelopathy is one of the mechanisms which invasive alien species invade successfully and spread rapidly. In order to explore the allelopathic mechanism of an invasive plant, Bidens pilosa L., genetic toxicity induced by the aqueous extracts of different quality concentration orB. pilosa was studied using micronucleus test technique of Viciafaba root tip cells and the paraffin section technique. The results showed that the aqueous extracts of B. pilosa produced genetic toxicity and could inhibit mitosis and cell growth of V. fara root tip cells. The mitotic indexes decreased and the micronucleus frequency increased with the increase of quality concentration and prolonging of action time. There were aberrant chromosomes of Vicia faba root tip cells such as micronucleus, chromosome bridge, chromosome break, chromosome lag, chromosome conglutination and three pole divide. Root tip generally became shorter and thicker because the aqueous extracts orB. pilosa could accelerate periclinal divisions and increased cell layers of the maturation zone and inhibit cell elongation. The present research showed water-solubility allelopathic substance in B. pilosa L. had the effect on genetic stability and cell shape of plant and allelopathy of B. pilosa L. was one of the invasive mechanisms.
出处
《生态环境》
CSCD
北大核心
2007年第3期944-949,共6页
Ecology and Environmnet
基金
成都市科技局攻关计划项目(200638)
四川师范大学校级重点项目(061k008)
