Can stress response genes be used to improve the symbiotic performance of rhizobia?

AIMS Microbiology

José Rodrigo da-Silva¹  Clarisse Brígido¹  Ana Alexandre¹  Solange Oliveira¹ 

[1] Laboratório de Microbiologia do Solo, Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), Instituto de Investigação e Formação Avançada (IIFA), Universidade de Évora, Apartado 94, 7002-554 Évora, Portugal;

关键词: biological nitrogen fixation;    rhizobia;    legume;    stress response;    symbiotic effectiveness;    improvement;    chaperone;   

DOI  :  10.3934/microbiol.2017.3.365

来源: DOAJ

【 摘 要 】

Rhizobia are soil bacteria able to form symbioses with legumes and fix atmospheric nitrogen, converting it into a form that can be assimilated by the plant. The biological nitrogen fixation is a possible strategy to reduce the environmental pollution caused by the use of chemical N-fertilizers in agricultural fields. Successful colonization of the host root by free-living rhizobia requires that these bacteria are able to deal with adverse conditions in the soil, in addition to stresses that may occur in their endosymbiotic life inside the root nodules. Stress response genes, such as otsAB, groEL, clpB, rpoH play an important role in tolerance of free-living rhizobia to different environmental conditions and some of these genes have been shown to be involved in the symbiosis. This review will focus on stress response genes that have been reported to improve the symbiotic performance of rhizobia with their host plants. For example, chickpea plants inoculated with a Mesorhizobium strain modified with extra copies of the groEL gene showed a symbiotic effectiveness approximately 1.5 fold higher than plants inoculated with the wild-type strain. Despite these promising results, more studies are required to obtain highly efficient and tolerant rhizobia strains, suitable for different edaphoclimatic conditions, to be used as field inoculants.

【 授权许可】

Unknown