韩国假单胞菌YBZ2缓解核桃盐胁迫作用效果研究  

Study on the Alleviating Effect of Pseudomonas koreenis YBZ2 on Salt Stress in Walnut Seedlings

作　　者：芦朋飞 蓝明明 徐亚茹 吴迪[1,2] 王卫雄[1,2] 董凯 牛犇 裴东 LU Peng-fei;LAN Ming-ming;XU Ya-ru;WU Di;WANG Wei-xiong;DONG Kai;NIU Ben;PEI Dong(State Key Laboratory of Tree Genetics and Breeding,Northeast Forestry University,Harbin 150040,Heilongjiang,China;College of Life Sciences,Northeast Forestry University,Harbin 150040,Heilongjiang,China;State Key Laboratory of Tree Genetics and Breeding,Key Laboratory of Silviculture of National Forestry and Grassland Administration,Research Institute of Forestry,Chinese Academy of Forestry,Beijing 100091,China)

机构地区：[1]东北林业大学林木遗传育种全国重点实验室,黑龙江哈尔滨150040 [2]东北林业大学生命科学学院,黑龙江哈尔滨150040 [3]林木遗传育种全国重点实验室,国家林业和草原局林木培育重点实验室,中国林业科学研究院林业研究所,北京100091

出　　处：《林业科学研究》2025年第1期39-49,共11页Forest Research

基　　金：2023年度新疆维吾尔自治区“揭榜挂帅”项目;“天池英才”引进计划;国家重点研发计划项目(2023YFD2200303)。

摘　　要：[目的]筛选核桃耐盐促生菌株,探究其提高核桃耐受高盐胁迫的作用效果。[方法]采用含盐选择培养基从核桃根系、根际与外围土壤分离筛选耐盐促生细菌,利用温室盆栽试验评估高盐胁迫下耐盐促生菌株对核桃生长及生理特性的影响。[结果]本研究从核桃根系、根际与外围土壤分离获得的397株细菌菌株中,筛选获得1株能够有效缓解核桃幼苗高盐胁迫的根际耐盐促生细菌YBZ2,鉴定为韩国假单胞菌(Pseudomonas koreenis)。研究发现,在125 mmol·L^(-1)NaCl处理的核桃幼苗根部接种菌株YBZ2能够有效提升植株的耐盐能力,显著增加核桃主根的鲜质量与根系活力。菌株YBZ2亦能够显著提高核桃叶片中抗氧化酶(超氧化物歧化酶、过氧化物酶和过氧化氢酶)的活性,降低叶片中丙二醛的含量。转录组测序分析的结果表明,接种YBZ2的核桃植株显著上调的差异表达基因主要富集于光合作用、卡尔文循环碳固定、淀粉和蔗糖代谢、植物激素信号转导、谷胱甘肽代谢、苯丙烷生物合成等途径,推测菌株YBZ2可能通过调控上述通路增强核桃抵御盐胁迫的能力。[结论]本研究筛选获得的核桃根际耐盐促生韩国假单胞菌YBZ2能够显著改善高盐胁迫下核桃根系的生长,提高植株的抗氧化酶活性,有效缓解高盐胁迫对核桃幼苗的损伤,诱导核桃耐盐相关代谢通路基因的上调表达,提升其抵御高盐胁迫的能力。本研究为核桃耐盐促生微生物制剂的研发与高效应用积累了菌种资源,同时为阐明耐盐促生细菌增强核桃耐盐性的分子机制奠定理论基础。[Objective]To screen out saline-tolerant plus growth-promoting bacteria and explore their effects on enhancing salt tolerance of the walnut seedlings.[Method]Saline-tolerant and growth-promoting bacteria were isolated from roots,rhizosphere soil and bulk soil of walnut trees.They were screened by using selective culture medium supplemented with 3%NaCl.The effect of these strains on the growth and physiological characteristics of walnut seedlings were evaluated under saline stress using pot experiments.[Result]In this study,three hundred and ninety-seven bacterial strains were isolated from walnut roots and soil.A saline-tolerant and growth-promoting bacterium YBZ2,which can effectively enhance the growth of walnut seedlings under saline stress,was obtained and identified as Pseudomonas koreenis.In the treatment with 125 mmol·L^(-1) NaCl,the inoculation of strain YBZ2 can effectively improve the saline tolerance of walnut seedlings,significantly increase the fresh weight of walnut main roots and root vitality.The inoculation of strain YBZ2 can also significantly increase the activity of antioxidant enzymes(SOD,POD,and CAT)and reduce the content of MDA in the leaves of walnut seedlings.Transcriptomic analysis showed that the differentially expressed genes significantly upregulated in the walnut seedlings inoculated with YBZ2 were mainly enriched in the pathways involved in photosynthesis,carbon fixation by Calvin cycle,starch and sucrose metabolism,plant hormone signal transduction,glutathione metabolism,phenylpropanoid biosynthesis,etc.It is speculated that strain YBZ2 may enhance the salt tolerance of walnut seedlings by regulating these pathways.[Conclusion]The saline-tolerant and growth-promoting bacterium P.koreenis YBZ2 is able to improve the growth of walnut roots,enhance antioxidant enzyme activity,improve the salt tolerance of walnut seedlings,induce the upregulation of genes related to saline tolerance pathways and alleviate the damages of walnut seedlings caused by salt stress.By carrying out this study

关 键 词：核桃 盐胁迫 韩国假单胞菌YBZ2 生理特性 转录组 

分 类 号：S664.1[农业科学—果树学] S792.13[农业科学—园艺学]