DNA甲基化影响不同倍性西瓜抗旱锻炼相关生理指标的分析  

Effects of DNA Methylation on Physiological Indexes Related to Drought Hardening in Watermelon with Different Ploidy

作　　者：王潇晴 高宇 江雪飞 乔飞[2] WANG Xiaoqing;GAO Yu;JIANG Xuefei;QIAO Fei(School of Tropical Agriculture and Forestry,Hainan University/Key Laboratory for Quality Regulation of Tropical Horticultural Crops of Hainan Province,Danzhou,Hainan 571737,China;Tropical Crops Genetic Resources Institute,Chinese Academy of Tropical Agricultural Sciences,Haikou,Hainan 571101,China;Sanya Institute of Breeding and Multiplication,Hainan University,Sanya,Hainan 572025,China)

机构地区：[1]海南大学热带农林学院/海南省热带园艺作物品质调控重点实验室,海南儋州571737 [2]中国热带农业科学院热带作物品种资源研究所,海南海口571101 [3]海南大学三亚南繁研究院,海南三亚572025

出　　处：《热带作物学报》2025年第4期968-977,共10页Chinese Journal of Tropical Crops

基　　金：国家自然科学基金项目(No.32260801);海南省自然科学基金高层次人才项目(No.321RC473)。

摘　　要：为了探索DNA甲基化对不同倍性西瓜抗旱锻炼的影响,本研究以不同倍性西瓜悬浮培养细胞为材料,使用甘露醇(Mannitol)模拟干旱胁迫,经过胁迫、恢复、再胁迫的方法测定细胞生长情况和抗性相关生理指标。同时,利用DNA甲基转移酶抑制剂5-氮杂胞苷(5-AzaC)处理,探索甲基化对这些生理指标的影响。结果表明,在干旱条件下,抗逆锻炼对细胞的生长有显著的保护作用。但是,5-AzaC抑制了细胞的质外体碱化,提升了丙二醛(MDA)含量,使脯氨酸(Pro)含量和超氧化物歧化酶(SOD)等保护酶活性降低,加剧了渗透胁迫的损伤,部分逆转了细胞抗旱锻炼的效果,且在西瓜二倍体和三倍体细胞中尤其明显。通过主成分分析发现,MDA、Pro含量和苯丙氨酸解氨酶(PAL)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性指标可以作为西瓜细胞干旱胁迫抗逆锻炼效果的主要评定指标。本研究可为DNA甲基化参与西瓜抗性锻炼效果的评价指标筛选和形成机制提供参考。In order to explore the effect of DNA methylation on drought hardening of different ploidy watermelon,mannitol was used to mimic drought stress in suspension cultured cells of different ploidy watermelon.The cell growth and resistance related physiological indexes were measured after stress,recovery and re-stress treatments.Meanwhile,the DNA methyltransferase inhibitor 5-azacytidine(5-AzaC)was used to explore whether methylation is involved in resistance regulation.The results showed that 5-AzaC could retard the growth,inhibit the extracellular alkalization,increase the content of malondialdehyde,bring down the content proline and the activity of protective enzymes such as SOD in all types of cells.Moreover,it caused the membrane permeability raising in diploid and triploid cells.Above results suggest that 5-AzaC can aggravate the osmotic stress injury and reverse the effects of drought hardening partially.Principal component analysis revealed that malondialdehyde content,proline content,PAL,CAT and APX activity could be used as the main evaluation indexes for evaluation the effect of drought hardening.This study would provide clues for mining the physiological indexes for evaluate the effects of stress hardening and the mechanism of DNA methylation involved in watermelon resistance regulation.

关 键 词：西瓜 倍性 DNA甲基化 干旱胁迫 生理指标 抗旱锻炼 

分 类 号：S651[农业科学—果树学]