外源物质对连作豇豆生长发育及其根际r土壤理化性质的影响

摘要

以豇豆为材料,通过盆栽试验探究茉莉酮酸甲酯、水杨酸和油菜素内酯3种外源物质对连作逆境条件下豇豆生长发育各项指标的影响.结果表明:不同外源物喷施处理均影响豇豆生长发育以及根际土壤环境.其中油菜素内酯处理效果最好,与对照相比,豇豆的茎粗、鲜质量、干质量和壮苗指数分别显著增加了10.57%、36.61%、32.02%和40.00%.同时,油菜素内酯处理显著降低豇豆叶片中丙二醛和脯氨酸的含量,降幅分别为58.57%和48.91%.喷施水杨酸和油菜素内酯显著影响豇豆叶片的叶绿素含量,而茉莉酮酸甲酯处理无显著性影响.3种处理均能改善豇豆根际土壤理化结构、提高土壤酶活性和增加土壤微生物数量.可见,豇豆叶片喷施外源物质在一定程度上可以缓解连作逆境胁迫对豇豆生长发育的危害,研究有助于为今后提高豇豆抗逆能力提供理论依据和实践指导.%In this experiment, cowpea was used as the material, the effect of different extraneous sub-stances including methyl jasmonate,salicylate acid and brassinosteroids on the growth of cowpea plants as well as the rhizosphere soil environment were studied under the condition of continuous cropping.The results showed that the three exogenous substances influenced cowpea growth and rhizosphere soil environment.The indexes in-cluding cowpea,stem diameter,fresh weight,dry weight and seedling index were the highest after brassinoste-roids treatment compared with other treatments, which were increased by 10. 57%、36. 61%、32. 02% and 40.00% respectively compared with the control. At the same time,brassinosteroids treatment significantly re-duced MDA and proline content by 58.57% and 48.91% in cowpea leaves.In addition,brassinosteroids and salicylic acid treatment could significantly improve the chlorophyll content of cowpea leaves, but methyl jas-monate did not showed such effect.Those three treatments improved the cowpea rhizosphere soil environment, including soil enzyme activity and soil microorganism.Comprehensive analysis concluded that different extrane-ous substances especially brassinosteroids can alleviate the damage of continuous cropping obstacles to cowpea growth and soil microorganism, which provides a theoretical and practical guidance for improving yield and quality of cowpea.