烟草科技2019，Vol.52Issue(9)：1-9,9.
外源亚精胺对渗透胁迫下烤烟幼苗生长及生理特性的影响
Effects of exogenous spermidine on growth and physiological characteristics of flue-cured tobacco seedlings under osmotic stress
摘要
Abstract
To explore the alleviation mechanism of exogenous spermidine (Spd) on the growth of plant under osmotic stress, hydroponic experiments were conducted on flue-cured tobacco of cv. Yuyan 6 in laboratories to study the effects of exogenous Spd at different concentrations(0, 0.2, 0.4 and 0.6 mmol·L-1). Plant growth, active oxygen metabolism, antioxidant enzymes, relative chlorophyll content(Soil and Plant Analyzer Development, SPAD)and photosynthetic fluorescence characteristics of flue-cured tobacco seedlings under osmotic stress were simulated by polyethylene glycol (PEG-6000). The results showed that osmotic stress inhibited the growth of tobacco seedlings, while spraying exogenous Spd on leaves significantly increased the biomass, root length, root surface area, root average diameter and root tip number of tobacco seedlings. In addition, the treatment enhanced the activities of superoxide dismutase(SOD), peroxidase(POD)and catalase(CAT), reduced O2.- producing rate and malondialdehyde(MDA)content, and raised the relative chlorophyll content, net photosynthetic rate(Pn), transpiration rate (Tr), stomatal conductance (Gs), maximal photochemical efficiency of PSⅡ(Fv/Fm), actual photochemical efficiency of PSⅡ( Φ PS Ⅱ) and photochemical quenching coefficient (qP), and decreased intercellular carbon dioxide concentration(C)i and non-photochemical quenching coefficient(NPQ)of tobacco seedlings under osmotic stress; especially Spd at the concentration of 0.4 mmol·L-1. Therefore, exogenous Spd could effectively improve the antioxidant capacities of flue-cured tobacco seedlings under osmotic stress, reduce the accumulation of reactive oxygen radicals to maintain the stability of cell membrane, promote root development, photochemical electron transport efficiency and photosynthesis; thereby the damage of flue-cured tobacco seedlings caused by osmotic stress alleviates.关键词
烤烟/亚精胺/渗透胁迫/生理特性/活性氧代谢/光合荧光特性Key words
Flue-cured tobacco/Spermidine/Osmotic stress/Physiological characteristic/Active oxygen metabolism/Photosynthetic fluorescence分类
农业科技引用本文复制引用
李冬,王艳芳,申洪涛,王丽君,李丽华,赵世民,刘领,段卫东..外源亚精胺对渗透胁迫下烤烟幼苗生长及生理特性的影响[J].烟草科技,2019,52(9):1-9,9.基金项目
国家自然科学基金项目"生物炭输入对旱作玉米氧化亚氮(N2O)排放的影响及菌根调节机制"(31700367) （N2O）
河南省高等学校青年骨干教师培养计划项目"生物炭输入对玉米/花生间作种间调控效应及根际微生态机制"(2016GGJS-062) （2016GGJS-062）
洛阳市烟草公司资助项目"洛阳烟叶焦甜正甜品质彰显暨在‘黄金叶’产品中的应用提升"(LYKJ201803). （LYKJ201803）
