黄建 马占峰 王念磊 刘润生 张海伟

摘要 采用室内低温胁迫模拟试验，研究了不同生育期烟苗在低温条件下叶片生理生化变化。研究表明，不同生育期烟苗对低温胁迫均产生一定响应，低温处理下，所有处理的烟苗叶绿素含量均较对照降低，而可溶性糖含量、丙二醛含量、电解质渗透率均较对照增高，这是对低温胁迫的生理响应机制。综合来看，以6叶1心生育期的烟苗叶绿素含量降幅较小，且其他生理物质增幅较小，说明该生育期烟苗能够更好地抵抗低温胁迫。

关键词 低温;烤烟;生育期;生理特性;渗透调节物质

中图分类号 S572 文献标识码 A

文章编号 0517-6611（2021）17-0046-03

doi：10.3969/j.issn.0517-6611.2021.17.013

Abstract The physiological and biochemical changes of flue-cured tobacco leaves at different growth stages under low temperature stress were studied in laboratory. The results showed that the seedlings of different growth stages had a certain response to low temperature stress. Under low temperature treatment， the chlorophyll content of all seedling ages was lower than that of the control， the contents of soluble sugar， malondialdehyde and electrolyte permeability were higher than those of the control， which was the physiological response mechanism to low temperature stress. The chlorophyll content of 6-leaf-1-heart seedling decreased little， and the other physiological substances increased little， which showed that the seedling could resist the low temperature stress better.

Key words Low temperature;Flue-cured tobacco;Growth stages;Physiological characteristic;Osmotic adjustment substance

近年來，为了培育适时、整齐和健壮的无病毒烟苗的烤烟壮苗，国内很多烟区开展了播种期和苗龄方面的研究[1-3]。由于烟苗移栽后在大田期容易受到低温的影响，苗龄与低温胁迫的关系研究也需要引起重视。研究表明，低温胁迫下植物叶片活性氧大量产生，导致细胞膜的相变或氧化损伤[4]，极端低温还会破坏细胞内环境的平衡，破坏植物正常的新陈代谢[5]。烟苗移栽后受到低温寒潮侵袭时还会出现早花现象[6-7]，对烟叶生长及产质量造成较大的影响。骆启章等[8]研究指出，烟草6～12片真叶时为低温敏感阶段。段雯等等[9]认为，不同苗龄的烟苗对低温胁迫的敏感程度有较大差异。江西烟区早春气温偏低且多为寡照天气，烟苗移栽后容易受到“倒春寒”等恶劣天气影响[10]，对烟叶的品质影响较大。鉴于此，笔者以江西主栽烤烟品种云烟87为试验材料，在光照培养箱条件下，研究不同生育期的烟苗对持续低温的敏感程度，为优质烤烟大田生产中培育壮苗提供理论支撑。……