外源NO缓解紫茎泽兰提取物对黄瓜根边缘细胞的化感胁迫  

Exogenous NO application effectively alleviates the allelochemical stress on cucumber root border cells caused by Eupatorium adenophorum extracts

作　　者：杨小环[1] 杨文秀 孙亮亮[1] 赵倩 曹永恒 马金虎[3] 

机构地区：[1]山西农业大学农学院,山西太谷030801 [2]云南农业大学热带作物学院,云南普洱665000 [3]山西农业大学园艺学院,山西太谷030801

出　　处：《应用生态学报》2018年第1期223-230,共8页Chinese Journal of Applied Ecology

基　　金：山西省科技攻关项目(20150311016-5)资助~~

摘　　要：以津优35号黄瓜为材料,采用根尖悬空气培养的方法,研究了紫茎泽兰提取物对黄瓜根边缘细胞的化感胁迫,以及外源NO缓解化感胁迫的效应.结果表明:1000 mg·L^(-1)紫茎泽兰提取物对黄瓜根尖有明显的伤害作用,根尖组织结构被破坏,根尖表层细胞脱落,细胞排列混乱且疏松;这些伤害能够被外源NO有效缓解.与对照相比,紫茎泽兰提取物处理黄瓜幼苗根尖根边缘细胞(RBC)的数量和细胞活率被显著抑制,分别降低54.5%和97.2%,细胞凋亡率升高12.3倍,RBC的黏胶层厚度增加31.4%,根边缘细胞根冠果胶甲基酯酶(PME)活性显著增加.与紫茎泽兰提取物处理相比,提取物胁迫下添加外源NO处理的RBC数量和细胞活率分别增加72.4%和146.0%,细胞凋亡率和RBC黏胶层厚度分别降低30.7%和15.0%,PME活性在处理72 h时降低了14.3%.紫茎泽兰提取物对黄瓜RBC产生细胞毒性,诱导细胞发生凋亡和死亡,破坏RBC对根尖的保护,提取物进一步对根尖产生胁迫伤害,破坏根尖的组织结构.外源NO可以在一定程度上缓解提取物对黄瓜根尖及RBC的化感胁迫伤害.Using suspension cultures of cucumber （Cucumis sativus） cultivar Jinyou 35, we investigated the effects of allelochemical stresses induced by Eupatorium adenophorum extracts on root border cells （RBC）, and the role of exogenous NO application in alleviation of the damage of root tips exposed to E. adenophorum extracts. The results showed that, 1000 mg·L-1 E. adenophorum extracts had significant damage to the cucumber root tip, resulting in severe tissue damage, exfoliated surface cells and irregular arrangement of inner cells, while those damages could be effectively alleviated by spraying exogenous NO. Compared with the control, E. adenophorum extracts （ZL） markedly reduced RBC numbers and survival rates by 54.5% and 97.2%, respectively, the RBC apoptosis rates were 12.3 times higher, the thicknesses of RBC adhesive layers were increased by 31.4%, and the root cap PME activities were markedly increased. Compared with the ZL treatment, exogenous NO application （ZN） significantly increased RBC numbers and survival rates by 72.4% and 146.0%, respectively, reduced the corresponding RBC apoptosis rates and the thicknesses of RBC adhesive layers by 30.7% and 15.0%, respectively, and inhibited the PME activities by 14.3% upon treatment for 72 hours. Our findings revealed that E. adenophorum extracts showed toxic effects on the cucumber RBC, resulting in cell apoptosis, abolishment of the RBC protection on root tips, and the destruction of root tip structure. Exogenous NO application, to some extent, could prevent the root tip and RBC from cell damage caused by E. adenophorum extracts.

关 键 词：一氧化氮 黄瓜 紫茎泽兰提取物 根边缘细胞 化感胁迫 

分 类 号：S451[农业科学—植物保护] S642.2