Endophytic Microbes from Diverse Wheat Genotypes and Their Potential Biotechnological Applications in Plant Growth Promotion and Nutrient Uptake

Abstract

Endophytic microbes residing inside the tissues of plants play a significant role to enhance the growth and health of plants by different plant growth-promoting mechanisms. In the present investigation, N2-fixing endophytic bacteria were isolated and characterized by plant growth. A total of one hundred fifty-nine endophytic bacteria were isolated from surface-sterilized roots and stem of different genotypes of wheat growing in the Divine Valley of Baru Sahib, Himachal Pradesh. The isolated bacterial endophytes were screened in vitro for plant growth-promoting attributes. Out of one hundred fifty-nine, thirteen endophytic bacteria were selected based on multifarious plant growth-promoting attributes. Among plant growth-promoting activities, hydrogen cyanide producers (19%) were higher when compared to siderophores producers (16%) and P-solubilizers (16%), ammonia producers (14%), K-solubilizers (14%), IAA producers (12%), Zn-solubilizers (5%), N2-fixers (2%) and biocontrol (2%). One of the isolates EU-B2RT.R1 demonstrated that a significant level of nitrogenase activity, P-solubilization and IAA production was identified as Acinetobacter guillouiae EU-B2RT.R1 based on 16S rRNA gene sequencing and BLAST analysis. Acinetobacter guillouiae EU-B2RT.R1, exhibiting multifarious beneficial traits, is further evaluated for plant growth promotion of wheat cultivar PBW 343+Lr24+GPC in pot experiment under greenhouse conditions. The Acinetobacter guillouiae EU-B2RT.R1 with multifarious plant growth-promoting activity has emerged as one of the efficient biofertilizers that need to be explored for sustainable agriculture.