青稞根边缘细胞的发育特性及其对密花香薷挥发油胁迫的响应  

Developmental characteristics of Hordeum vulgare L.root border cells and their responses to volatile oil of Elsholtzia densa Benth.

作　　者：周汐婕 肖云星 谢雨思 马丹炜[1] ZHOU Xi-jie;XIAO Yun-xing;XIE Yu-si;MA Dan-wei(College of Life Science,Sichuan Normal Universtiy,Chengdu 610101,China)

机构地区：[1]四川师范大学生命科学学院,成都610101

出　　处：《西南农业学报》2023年第7期1393-1399,共7页Southwest China Journal of Agricultural Sciences

基　　金：四川省科技厅应用基础重点项目(2020YJ0335);第四次全国中药资源普查(2019PC006)。

摘　　要：【目的】探讨农作物青稞(Hordeum vulgare L.)根边缘细胞(Root border cells,RBCs)对挥发油的防御响应机制,为青藏高原农田生态系统农作物的保产增产提供理论依据。【方法】采用纯琼脂悬空气培养法,在研究青稞RBCs发育特性基础上,探讨青稞RBCs从细胞活性、粘胶层厚度、胞内活性氧(Reactive oxygen species,ROS)水平变化以及细胞死亡类型等方面对不同浓度密花香薷(Elsholtzia densa Benth.)挥发油的响应。【结果】青稞RBCs围绕根尖形成保护层,细胞形态呈圆形、弧形以及杆形,细胞长30~150μm,宽10~30μm;在5~40 mm根长范围内,青稞RBCs数量与根长呈正相关,在根长40 mm时达到峰值(1263个),此时RBCs数量为根长5 mm时的2.37倍;不同根长的RBCs存活率均维持在90%以上。经过密花香薷挥发油处理的青稞RBCs出现浅橘红色荧光,细胞核呈现橘红色荧光亮斑,RBCs活性丧失。随着挥发油处理浓度增加,青稞RBCs粘胶层厚度与细胞活性呈浓度依赖性变化;与对照相比,在最高浓度0.1μL/μL作用下,青稞RBCs粘胶层厚度增加1.64倍,细胞活性下降59.83%;同时,细胞内ROS水平呈上升趋势,在T3(0.06μL/μL)浓度处理下ROS相对荧光值达到最高(2.23);当挥发油和泛Caspase抑制剂Z-VAD-FMK共同作用时,由挥发油引起的细胞活性降低现象得以缓解,与未使用Z-VAD-FMK相比,细胞活性升高17.3%。【结论】青稞RBCs受到密花香薷挥发油胁迫后,通过增厚粘胶层抵御外界胁迫侵害,并产生ROS诱导细胞凋亡,从而缓解化感毒性。【Objective】The present study aimed to elucidate the defense response mechanism of Hordeum vulgare L.root border cells(RBCs)to volatile oil and provide theoretical basis for crop yield preservation and increase in farmland ecosystem of Qinghai-Tibet Plateau.【Method】The pure agar suspension air culture method was adopted.Based on the research of development characteristics of H.vulgare RBCs,the changes of activity,the mucilage layer thickness,intracellular reactive oxygen species(ROS)levels and cell death types of H.vulgare RBCs treated with different concentrations of Elsholtzia densa Benth.volatile oil(0,0.02,0.04,0.06,0.08 and 0.1μL/μL)were investigated.【Result】The RBCs of H.vulgare which were round,arc and rod-shaped formed a protective layer around the root tip.The cells were 30-150μm long and 10-30μm wide.In the range of 5-40 mm root length,the number of RBCs of H.vulgare was positively correlated with the root length,and reached the peak(1263)when the root length was 40 mm.In this case,the number of RBCs was 2.37 times that when the root length was 5 mm.The survival rate of RBCs with different lengths was above 90%.After treatment with volatile oil of E.densa,the RBCs of H.vulgare showed light orange red fluorescence,and the nucleus showed bright orange red fluorescence spots,which indicated the loss of RBCs activity.With the increase of the concentration of volatile oil,the mucilage layer and cell activity of the RBCs of H.vulgare changed in a concentration dependent manner.Compared with the control,at the highest concentration of 0.1μL/μL,the mucilage layer of the RBCs increased by 1.64 times,and the cell activity decreased by 59.83%.At the same time,intracellular ROS levels showed an upward trend,and the ROS relative fluorescence value reached the highest(2.12)at T3 concentration(0.06μL/μL).When the volatile oil and pan-caspase inhibitor Z-VAD-FMK were combined together,the decrease in cell activity caused by volatile oil was alleviated,and the cell activity was increased by 17.3%compa

关 键 词：青稞 根边缘细胞发育 挥发油 化感胁迫响应 

分 类 号：S512.3[农业科学—作物学]