外源钙对NaHCO_(3)胁迫下油菜幼苗叶片离子平衡及光合特性的影响  

Effects of exogenous calcium on ion balance and photosynthetic characteristics in leaves of rapeseed seedlings under NaHCO_(3)stress

作　　者：曹小强 王卫超[1] 阴法庭 张凤华[1] CAO Xiaoqiang;WANG Weichao;YIN Fating;ZHANG Fenghua(College of Agronomy/Xinjiang Production and Construction Group Key Laboratory of Oasis Eco-Agriculture,Shihezi University,Shihezi 832003,China)

机构地区：[1]石河子大学农学院/新疆生产建设兵团绿洲生态农业重点实验室,石河子832003

出　　处：《华中农业大学学报》2023年第5期149-157,共9页Journal of Huazhong Agricultural University

基　　金：国家重点研发项目子课题(2021YFD1900802-3);新疆生产建设兵团科技合作计划项目(2020BC001)。

摘　　要：为探究碱胁迫下油菜幼苗叶片离子平衡与光合特性对外源Ca^(2+)的响应,深入理解添加外源Ca^(2+)缓解油菜幼苗碱胁迫的作用机制,以5叶期油菜华油杂62(耐盐品种)与湘油15(盐敏感品种)为材料,在NaHCO_(3)(100 mmol/L)胁迫下,设置6个CaCl_(2)水平:CK、0%、0.25%、0.5%、1%、2%(记为CK、T1、T2、T3、T4、T5),研究CaCl_(2)对油菜幼苗叶片离子平衡及光合特性的影响。结果显示:NaHCO_(3)胁迫下,油菜幼苗将更多的Na+储存于叶片,将较多Ca^(2+)积累于根系,其中,湘油15体内离子的失衡较华油杂62更为显著;NaHCO_(3)胁迫下,叶面喷施0.5%CaCl_(2)对幼苗质膜损伤的修复最为显著,降低了幼苗叶片Na^(+)含量,提高了叶片K+与Ca^(2+)含量,其中对华油杂62叶片K+/Na+的提高及Ca^(2+)的增加更为显著。除潜在光化学效率(Fv/Fo)与最大光化学效率(Fv/Fm)外,NaHCO_(3)胁迫对湘油15光合特性的抑制均大于华油杂62,外源喷施0.5%CaCl_(2)提高了幼苗叶绿素a、叶绿素b、叶绿素总量、Fv/Fo、Fv/Fm、净光合速率、气孔导度及蒸腾速率,其中华油杂62对应各指标的增加量较湘油15更为显著。结果表明,叶面喷施CaCl_(2)能调控碱胁迫下油菜幼苗叶片离子平衡与光合特性并且对耐盐品种的改善更为显著。The five-leaf stage rapeseed Huayouza 62(salt-tolerant variety)and Xiangyou 15(saltsensitive variety)were used to study the response of ion balance and photosynthetic characteristics in leaves of rapeseed seedlings to exogenous Ca^(2+)under alkali stress and to deeply understand the mechanism of add⁃ing exogenous Ca^(2+)to alleviate alkaline stress in rapeseed seedlings.Under NaHCO_(3)(100 mmol/L)stress,six CaCl_(2)levels including CK,0%,0.25%,0.5%,1%,and 2%(denoted as CK,T 1,T 2,T3,T4,and T5)were set to obtain appropriate concentrations of spraying CaCl_(2)and to study their effects on ion balance and photosynthetic characteristics in leaves of rapeseed seedling.The results showed that rapeseed seedlings stored more Na+in their leaves and accumulated more Ca^(2+)in their roots under NaH⁃CO_(3)stress.The imbalance of ions in Xiangyou 15 was more significant than that in Huayouza 62.When the concentration of CaCl_(2)was 0.5%,the repair of plasma membrane damage under NaHCO_(3)stress was most significant,which reduced the content of Na+and increased the content of K+and Ca^(2+)in the leaves of rapeseed seedlings.Except for the potential photochemical efficiency(Fv/Fo)and the maximum photo⁃chemical efficiency(Fv/Fm),the inhibition of NaHCO_(3)stress on the photosynthetic characteristics of Xiangyou 15 was greater than that of Huayuza 62.Spraying 0.5%exogenous CaCl_(2)promoted the expres⁃sion of chlorophyll a,chlorophyll b,total chlorophyll,Fv/Fo,Fv/Fm,net photosynthetic rate,stomatal conductance,and transpiration rate in seedlings.It is indicated that foliar spraying of CaCl_(2)can regulate ion balance and photosynthetic characteristics of rapeseed seedlings under alkaline stress,and its improvement is more significant for the salt-tolerant variety.

关 键 词：油菜幼苗 碱胁迫 CaCl_(2)叶面喷施 离子积累量 光合特性 

分 类 号：S565.4[农业科学—作物学]