摘要
采用盆栽试验方式,以低温敏感型番茄品种东农708(DN 708)和耐低温型番茄品种东农722(DN 722)为试验材料,研究24-表油菜素内酯(EBR)对亚低温胁迫下番茄幼苗生长和钾积累的影响。结果表明:与适宜温度相比,亚低温胁迫抑制了2个番茄品种幼苗的生长,显著降低了光系统Ⅱ最大光化学效率(F_v/F_m)以及茎与叶中K~+浓度,显著增加了丙二醛(MDA)含量和电解质渗透率,且亚低温胁迫对DN 708的影响大于DN 722;而外源施用EBR可有效缓解亚低温胁迫对番茄幼苗生长的抑制作用,显著提高了2个番茄品种的F_v/F_m,根、茎与叶中K~+浓度以及根和叶中LKT1、SIHAK5和SIHAK9基因的相对表达量,显著降低了MDA含量和电解质渗透率,且DN 708的变化幅度大于DN 722。综上所述,外源EBR可能通过促进转运相关基因的表达和K~+吸收,使番茄幼苗各器官中K~+浓度增加,降低细胞膜脂过氧化程度,增强番茄幼苗对亚低温的适应性,外源EBR对低温敏感型番茄品种DN 708的亚低温胁迫缓解效应大于耐低温型番茄品种DN 722。
Taking 2 tomato varieties‘Dongnong 708’(‘DN 708’)sensitive to low temperature and‘Dongnong 722’(‘DN 722’)tolerant to low temperature as test materials,this paper studied the effects of 24-epibrassinolide(EBR)on tomato growth and potassium accumulation under sub-low temperature condition.The results showed that comparing with the suitable temperature,low temperature stress could inhibit the seedling growth of these 2 tomato varieties,and remarkably reduce the maximum photochemical efficiency of PSII(Fv/Fm),and K+concentrations in stems and leaves,and significantly increase the malondialdehyde(MDA)content and electrolyte permeability.Moreover,the effects of sub-low temperature stress on‘DN 708’was greater than that on‘DN 722’.While,exogenous EBR effectively alleviated the inhibition of sub-low temperature stress on tomato seedling growth,significantly improved Fv/Fm,K+concentrations in roots,stems and leaves of these 2 tomato varieties,and increased relative expression levels of LKT1,SIHAK5 and SIHAK9 genes in roots and leaves,and significantly reduced MDA content and electrolyte permeability in seedlings of these 2 tomato varieties.And the variation range in‘DN 708’was greater than that in‘DN 722’.To sum up,exogenous EBR may increase the K+concentration in various organs of tomato seedlings by promoting the expression of transport related genes and K+absorption,reduce the degree of cell membrane peroxidation,and enhance the adaptability of tomato seedlings to sub-low temperatures condition.Thus,exogenous EBR has a greater mitigation effect on low temperature sensitive tomato variety‘DN 708’under sub-low temperature stress than low temperature tolerant tomato variety‘DN 722’.
作者
杨莲
高欢
吴凤芝
YANG Lian;GAO Huan;WU Fengzhi(College of Horticulture and Landscape Architecture,Northeast Agricultural University,Harbin 150030,Heilongjiang,China)
出处
《中国蔬菜》
北大核心
2021年第1期48-55,共8页
China Vegetables
关键词
24-表油菜素内酯
亚低温
番茄
钾
钾吸收转运相关基因
24-epibrassinolide
sub-low temperature
tomato
potassium
K+absorption and transport related gene
