低温胁迫对2个石榴品种幼苗光合参数和生理特性的影响  

Effects of low temperature stress on photosynthetic parameters and physiological characteristics for seedlings of two pomegranate varieties

作　　者：关思慧 柴亚倩 崔洪鑫 宋晋泰 朱光裕 刘慧英[1] 郝庆 刁明[1] GUAN Sihui;CHAI Yaqian;CUI Hongxin;SONG Jintai;ZHU Guangyu;LIU Huiying;HAOQing;DIAO Ming(School of Agriculture,Shihezi University/Key Laboratory of Physiology and Germplasm Resources Utilization Corps of Special Fruit and Vegetable Cultivation,Shihezi 832003,Xinjiang,China;Institute of Horticultural Crops,Xinjiang Academy of Agricultural Sciences,Urumqi 830000,Xinjiang,China)

机构地区：[1]石河子大学农学院·特色果蔬栽培生理与种质资源利用兵团重点实验室,新疆石河子832003 [2]新疆农业科学院园艺作物研究所,乌鲁木齐830000

出　　处：《果树学报》2023年第5期946-958,共13页Journal of Fruit Science

基　　金：新疆生产建设兵团科技攻关重点项目(2021AB015)。

摘　　要：【目的】研究不同低温胁迫下2个石榴品种光合、叶绿素荧光及生理特性的响应差异。【方法】采用盆栽方式,以1年生喀什酸石榴和突尼斯软籽石榴2个品种幼苗为试验材料,在人工气候室中模拟低温,设置5个温度水平的处理,探究低温处理期间2个石榴品种幼苗光合特性、叶绿素荧光参数、光合色素和渗透调节物质含量的变化,分析石榴的低温生理响应特性。【结果】随着胁迫温度的下降,叶绿素a含量、类胡萝卜素含量、总叶绿素含量、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、水分利用效率(wateruseefficiency,WUE)和最大光化学效率(Fv/Fm)、光化学猝灭系数(qP)、实际光化学效率[Y(Ⅱ)]均呈现下降趋势,脯氨酸含量、可溶性糖含量、可溶性蛋白含量、相对电导率、丙二醛(malondialdehyde,MDA)含量、非光化学淬灭系数(non-photochemicalquenching,NPQ)呈上升趋势,胞间CO_(2)浓度(Ci)呈先升后降趋势;随胁迫时间的延长,2个石榴品种净光合速率、气孔导度、水分利用效率、Fv/Fm和[Y(Ⅱ)]呈下降趋势,其余指标的变化趋势均有所不同。【结论】喀什酸石榴植株抗寒性显著强于突尼斯软籽石榴。喀什酸石榴叶片较厚重,在低温胁迫下抗脱水能力强,光合机构受损伤程度低,有较强维持叶绿素含量的能力,光合效率较高,同时维持细胞渗透调节能力和膜脂过氧化能力强。突尼斯软籽石榴在重度低温胁迫持续6d或极重度低温胁迫持续4d后其光合系统被严重破坏,叶片生长被抑制,出现低温冻害。该研究结果为寒冷地区引进软籽石榴的适栽区划分和防寒栽培管理技术的选择等提供理论依据。【Objective】The aim of this study was to investigate the effects of the low temperature stress on photosynthetic and physiological characteristics of Kashi acid pomegranate and Tunisia soft seed pomegranate in Xinjiang.Meanwhile,the cold resistance and suitable growth conditions of the two vari-eties were evaluated,so as to provide scientific basis for the introduction,breeding,and cultivation man-agement.【Methods】One year cuttings of the two varieties with different cold tolerance types(Kashi ac-id pomegranate:high cold resistance and Tunisia soft seed:cold resistance)were used as experimental materials and placed in an artificial climate chamber with gradient cooling.Five temperatures(CK:25℃,T1:6℃mild stress,T2:3℃moderate stress,T3:0℃severe stress,T4:-3℃very severe stress)and three durations(2,4 and 6 d)were set.During this period,the photosynthetic parameters,chlorophyll content,chlorophyll fluorescence characteristics,relative electrical conductivity,malondial-dehyde and osmotic regulatory substance(proline,soluble sugar and soluble protein)contents of pome-granates of the two varieties were measured.【Results】With the decrease of stress temperature,the contents of the chlorophyll a,carotenoids,total chlorophyll,net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductance(Gs),water use efficiency(WUE)and fluorescence parameters[Fv/Fm,qP,Y(Ⅱ)]showed a downward trend.Besides,the photosynthesis was inhibited by the decrease of tem-perature and the extending of stress time.The proline content of these two pomegranate varieties showed an increasing trend with the extension of stress time and the intensification of stress degree.The Kashi acid pomegranate had no significant change under mild stress,while the Tunisia soft seed pome-granate was sensitive to temperature and showed significant change.The increase of proline content was positively correlated with the degree of stress.The soluble sugar content of the Kashi acid pome-granate increased significantly after 2 d and 4 d of str

关 键 词：石榴幼苗 低温胁迫 光合 渗透调节 

分 类 号：S665.4[农业科学—果树学]