ISOLATION, SCREENING, AND CHARACTERIZATION OF RHIZOSPHERIC AND ENDOPHYTIC BACTERIA FOR DIFFERENT PLANT GROWTH PROMOTION (PGP) ACTIVITIES
Authors: Nurfadzilah M., Ishak Z., Fatien N.C.Y., & Norsalsabila M.R.
Journal Issue: Malaysian Cocoa Journal, Volume 13(2)/2021
Keywords: Isolation, Screening, Characterization, Rhizospheric and Endophytic Bacteria
Published On: 1/11/2021
Abstract
Plant growth-promoting rhizobacteria (PGPR) is a group of bacteria that colonize plant roots and enhance plant growth by a broad diversity of mechanisms while endophytic bacteria are defined as bacteria detected inside surface-sterilized plants or extracted from inside plants and having no visibly harmful effects on the plants. PGPR and endophytic bacteria comprise a heterogeneous genera of Pseudomonas, Burkholderia, Enterobacter, Rhizobium, Serratia, Arthrobacter, Flavobacterium, Azospirillum, Bacillus, Erwinia, and Acinetobacter and have been reported to enhance the plant nutrition. In the present study, five bacterial isolates were collected from cocoa environment. The objectives of the study were to determine the capabilities of PGPR isolated from cocoa environment and evaluate their efficiency to enhance the growth of cocoa seedlings under greenhouse conditions. Isolation and in vitro screening were done for different plant growth promotion activities i.e. nitrogen fixation, phosphate solubilization, ammonia production, ACC-deaminase activity and catalase activity. All five isolates showed several traits of nitrogen fixation, and phosphorus solubilization. All isolates were further screened for other PGP traits like catalase activity, ACC deaminase activity and ammonia production. In all PGP trait tests, all isolates showed the most prominent results for in vitro tests and suggested to further tested in vivo for growth promotion of cocoa seedlings under greenhouse conditions.