Isolation Characterization and the Exploration Of Biological Activity of Endophytic Bacteria Isolated From Selected Halophytes in Coastal Region of Andhra Pradesh

Abstract

Endophytic bacteria play a crucial role in promoting plant growth and newlineadaptation to adverse environmental conditions. This study focuses on isolation and newlinecharacterization of endophytic bacteria from halophytic plant species, aiming to newlineexplore their potential applications in agriculture, particularly in saline and nutrientdeficient newlinesoils. The primary aim of this research is to assess the functional traits of newlineendophytic bacteria to produce Plant Growth Promoting Characters (PGP) including newlineamylase production, proteolytic activity, indole-3-acetic acid (IAA) production, and newlinephosphate solubilization. The specific objectives involve isolating endophytic bacteria newlinefrom halophytic plants, conducting preliminary identifications, and evaluating their newlineenzymatic activities and functional characteristics in a non-pathogenic and newlineecofriendly manner. The study, conducted during 2020-21 and 2021-22 at the newlineDepartment of Botany, Andhra University, focused on two halophytic zones: newlineKhaspanaupada in Srikakulum and Corangi Mangrove Wildlife Sanctuary in East newlineGodavari district. Aerial and root samples of Suaedafruiticosa and Suaedamaritima newlinewere collected from Coringa Mangrove Wildlife Sanctuary, while plant tissue newlinesamples of Suaedanigra, Heliotropiumcurassavicum, Trianthematriquetrum, and newlineAsparagus aethiopicus were collected from Khaspanaupada, Srikakulam. A total of newline66 symbiotic endophytic bacterial isolates were cultured, enumerated, identified, newlinepurified, and preserved for subsequent studies. newlinePreliminary identification revealed the presence of three distinct bacterial newlinefamilies, including Bacillaceae, Vibrionaceae, and Enterobacteriaceae, comprising newlineinto five genera namely Bacillus, Pseudomonas, Vibrio, Coccobacilli, and Coccus, newlineindicating a rich and varied endophytic community. Among the 66 isolates, six strains newlinewere identified as potential plant growth-promoting (PGP) endophytes. Notably, newlinestrain HCR3, isolated from Heliotropiumcurassavicum exhibited IAA production at newline20 and#956;g/ml, phosphate solubilization at 1.5 PPM, and extracellular enz