低温胁迫对火龙果植株抗氧化系统及脂肪酸组分的影响
Effects of Low Temperature Stress on Antioxidant System and Fatty Acid Composition in Pitaya Plants
王晓莉 1罗弦 1王楚侨 1徐嘉宁1
作者信息
- 1. 四川农业大学园艺学院,成都 611130
- 折叠
摘要
[目的]探究低温胁迫下2种火龙果植株的耐寒性差异及机理.[方法]以'白水晶'和'台湾6号'火龙果植株为材料,设置适温(30℃/24℃)、冷害(15℃/8℃)、冻害(4℃/-2℃)3个温度梯度,分析火龙果植株的冷害指数、抗氧化系统及脂肪酸组分等的变化情况.[结果]低温胁迫使2种火龙果植株的冷害指数均升高,且在冻害下升高幅度更大;冷害和冻害下,'白水晶'的冷害指数均低于'台湾6号'.低温诱导2种火龙果植株的抗氧化酶活性显著升高,而'白水晶'抗氧化酶活性升高幅度始终高于'台湾6号';同时,'白水晶'植株ROS积累量、MDA含量和REC增幅更低.2种火龙果植株的不饱和脂肪酸相对含量及UFA/SFA随温度降低而降低;其中'白水晶'植株的降幅较小.[结论]低温胁迫使2种火龙果植株均受冻,其中'白水晶'的耐寒性强于'台湾6号'.在冷害和冻害下,'白水晶'植株保持较高的抗氧化酶活性和ROS清除能力,减轻膜脂过氧化伤害,提高脂肪酸不饱和度是其耐寒性较强的主要原因.结果可为亚热带地区火龙果植株的抗寒栽培提供一定的理论依据.
Abstract
[Objective]The objective of this study was to explore the mechanisms of cold tolerance in two varieties of pitaya under low-temperature stress.[Method]′Baishuijing′ and ′Taiwan No.6′ pitayas were used as materials to analyze changes in the chilling injury index(CI),antioxidant systems,and fatty acid composition across three temperature gradients:optimal(30°C/24°C),chilling(15°C/8°C),and freezing(4°C/-2°C).[Result]The CI of both pitaya varieties increased under low-temperature stress,with higher levels observed under freezing conditions.Under chilling and freezing conditions,the CI of ′Baishuijing′ was consistently lower than that of ′Taiwan No.6′.The activity of anti-oxidant enzymes in both pitaya plants significantly increased in response to low temperatures,with ′Bai-shuijing′ consistently showing higher activity than ′Taiwan No.6′.Additionally,′Baishuijing′ exhibited lower accumulation of reactive oxygen species(ROS),lower increases in malondialdehyde(MDA)con-tent,and reduced electrolyte leakage(REC).The relative content of unsaturated fatty acids and the ratio of unsaturated to saturated fatty acids(UFA/SFA)in both pitaya plants decreased with temperature re-duction,but this decline was less pronounced in ′Baishuijing′.[Conclusion]Both pitaya varieties were susceptible to freezing under low-temperature stress,but'Baishuijing'demonstrated stronger cold toler-ance than ′Taiwan No.6′.′Baishuijing′ maintained higher antioxidant enzyme activity and ROS scaveng-ing capacity,reduced membrane lipid peroxidation damage,and enhanced fatty acid unsaturation under chilling and freezing conditions,which are the main reasons for its enhanced cold tolerance.These find-ings provide a theoretical basis for the cold-resistant cultivation of pitaya in subtropical regions.
关键词
低温胁迫/火龙果/耐寒性/抗氧化系统/脂肪酸Key words
low temperature stress/pitaya plants/cold resistance/antioxidant system/fatty acid引用本文复制引用
基金项目
四川省衔接推进乡村振兴科技项目(2022ZHXC0097)
四川农业大学专业建设支持计划(2221998084)
出版年
2024
NETL
NSTL
维普
万方数据