叶面喷施烯效唑对盐胁迫下大豆幼苗生理及解剖结构的影响

Effect of Foliar Uniconazole Spraying under Salt Stress on Physiological and Anatomical Characteristics in Glycine max

以大豆栽培品种‘中黄13’为试验材料,在筛选合适的盐胁迫及烯效唑(S3307)浓度基础上,采用大豆幼苗期盐胁迫以及叶面喷施S3307的方法,分析比较相关生理指标及营养器官(根、茎和叶)解剖结构的差异,从组织结构形态和生理两方面探讨叶面喷施S3307对大豆苗期盐胁迫的缓解效应及其作用机制。结果显示:(1)与正常生长的对照相比,盐胁迫下大豆根和叶中硫代巴比妥酸反应物的含量均显著增加,叶绿素含量显著降低;而且叶片较薄,海绵组织和栅栏组织细胞排列混乱;根部中柱所占比例较对照明显变小,但皮层所占比例变大,外表皮细胞向内凹陷,次生导管平均孔径较小且含有侵填体;茎部解剖结构的变化与根部相类似。(2)叶面喷施80mg/L S3307后,盐胁迫大豆植株根和叶中硫代巴比妥酸反应物和叶绿素含量均恢复到接近对照的水平,且根、茎和叶解剖结构变化介于正常对照与盐胁迫处理之间。研究表明,叶面喷施80mg/L S3307能够有效缓解盐胁迫对大豆的伤害,且这种缓解作用与叶片细胞膜伤害、光合色素含量以及根、茎和叶内部组织结构改变有关,叶面喷施S3307可能是生产上提高大豆耐盐性的一种有效措施。

In this study,Glycine max‘Zhonghuang13’cultivar was used as the experimental material.On the basis of screening suitable concentrations of NaCl and uniconazole(S3307),the relative physiological indexes and anatomical structures of roots,stems and leaves were compared by foliar uniconazole spraying in order to understand whether spraying fronds with S3307can advance soybeans ability to cope with salt stress.The results indicated that:(1)TBARS contents in root and leaf were increased,and total chlorophyll and carotenoid contents were decreased significantly under salt stress.The anatomical structure of leaves showed that the leaf thickness was thinner with spongy and palisade tissue cells arranging in disorder under salt stress than control plants.For roots,salt stress caused that the proportion of cortex/root ratio became larger,but stele/root was smaller than controls.Additionally,the outer epidermis cells sagged inwards,and xylem vessel diameter decreased as compared to control plants,in partly containing the tylosis.The changes in stems were similar to those in roots.(2)Under salt stress plus leaf spraying of80mg/L S3307,TBARS contents,total chlorophyll and carotenoid contents were restored,and anatomical structures of roots,stems and leaves were between the control group and the salt treatment group.All these data indicated that spraying fronds with S3307can advance salt tolerance of soybean,suggesting that it may be a usable approach to enhance salt tolerance of cultivated soybean in practice.