丛枝菌根真菌对低磷胁迫下核桃幼苗根系磷吸收的影响及机制  

Effects of Arbuscular Mycorrhizal Fungi on Phosphorus Uptake of Walnut Seedling Roots under Low Phosphorus Stress and the Potential Mechanisms

作　　者：曹明奡 张菲 黄光明 刘瑞成 刘利平[1] 吴强盛[1] 徐永杰[3] Cao Ming'ao;Zhang Fei;Huang Guangming;Liu Ruicheng;Liu Liping;Wu Qiangsheng;Xu Yongjie(College of Horticulture and Gardening/Tibet Plateau Walnut Industry Research Institute,Yangtze University,Jingzhou 434025;Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization Huanggang Normal University,Huanggang 438000;Hubei Academy of Forestry Science,Wuhan 430075)

机构地区：[1]长江大学园艺园林学院/西藏高原核桃产业研究所,荆州434025 [2]黄冈师范学院经济林木种质改良与资源综合利用湖北省重点实验室,黄冈438000 [3]湖北省林业科学研究院,武汉430075

出　　处：《林业科学》2023年第12期117-124,共8页Scientia Silvae Sinicae

基　　金：湖北省“十四五”科技援藏项目(SCXX-XZCG-22016);湖北省重点研发计划项目(2022BBA153)。

摘　　要：【目的】探索低磷(P)胁迫下丛枝菌根(AM)真菌对核桃幼苗根系P吸收的影响及机制,为核桃幼苗的栽培生产提供参考。【方法】基于前期筛选的1个高效AM真菌菌株——沾屑多孢囊霉,分析适P(100μmol·L−1)和低P(1μmol·L−1)条件下沾屑多孢囊霉对‘辽河一号’核桃幼苗植株生长、根系构型、根系P含量、根系和土壤磷酸酶活性以及根系酸性磷酸酶分泌基因(JrPAP10和JrPAP12)和磷转运基因(JrPT3;1和JrPT3;2)相对表达量的影响。【结果】沾屑多孢囊霉接种3个月后,核桃幼苗根系侵染率达45.6%~53.2%,且低P处理可提高根系菌根侵染。在低P和适P条件下,接种沾屑多孢囊霉显著提高植物生物量和土壤酸性、中性和碱性磷酸酶活性;低P条件下沾屑多孢囊霉还显著改善植物根系构型,提高根系P含量以及根系酸性磷酸酶活性。根系JrPAP10和JrPT3;1均被沾屑多孢囊霉诱导表达,JrPAP12仅在低P条件时被沾屑多孢囊霉诱导表达,且JrPT3;2的表达量被沾屑多孢囊霉抑制。【结论】AM真菌菌株沾屑多孢囊霉诱导低P条件下核桃幼苗JrPAP10、JrPAP12和JrPT3;1基因的表达,可促进土壤和根系磷酸酶活性,改善根系构型,从而提高核桃幼苗P吸收和生物量积累。【Objective】Walnut is a high-quality economic forest tree.Arbuscular mycorrhizal(AM)fungi can promote plant growth and phosphorus(P)uptake,however,the mechanisms by which AM fungi enhance nutrient utilization and plant growth in walnuts are not clear.This study aims to explore the effect of AM fungi on P uptake of walnuts under low P conditions and the associated mechanisms.【Method】In this study,an effective AM fungal strain,Diversispora spurca,screened earlier,was used to inoculate Juglans regia cv.Liaohe 1 seedlings,and the effects of D.spurca on plant growth,root system architecture,root P,root and soil phosphatase activities,and the relative expression of root acid phosphatase secretion genes(JrPAP10 and JrPAP12)and phosphate transporter protein genes(JrPT3;1 and JrPT3;2)of J.regia cv.Liaohe 1 seedlings under appropriate P(100μmol·L−1)and low P(1μmol·L−1)level conditions were studied.【Result】After three months of inoculation with D.spurca,the mycorrhizal colonization of walnut root system reached 45.6%–53.2%,and low P treatment significantly increased root mycorrhizal colonization,compared with appropriate P treatment.Inoculation of D.spurca significantly increased plant biomass and soil acid,neutral,and alkaline phosphatase activities under both low and appropriate P levels conditions.D.spurca also significantly improved root morphology as well as increased root P content and root acid phosphatase activity under low P condition.Root JrPAP10 expression was up-regulated by D.spurca under both low and appropriate P levels conditions,while JrPAP12 expression was induced by D.spurca only under low P level condition.In addition,D.spurca up-regulated the relative expression of JrPT3;1in roots under both low P and appropriate P level conditions,while the expression of JrPT3;2 was inhibited by D.spurca.【Conclusion】The AM fungus,D.spurca,can induce up-regulated expressions of JrPAP10,JrPAP12,and JrPT3;1 in roots of walnut seedlings under low P levels conditions,increase soil phosphatase,root a

关 键 词：核桃 菌根 磷 磷酸酶 磷转运基因 

分 类 号：S718.43[农业科学—林学] S664.1