Isolation of potential fluorescent pseudomonads from Kuini (Mangifera odorata) planted soil and their potential as biofertilizer

Pseudomonas sp. are known to be good Plant Growth Promoting Rhizobacteria (PGPR). In this study, Pseudomonas sp. were isolated from soil planted with kuini (Mangifera odorata) using soil dilution method and spread onto King’s B media. Five isolates of Pseudomonas sp. were observed to give promising results in the phytohormone and antimicrobial test conducted. These isolates are Pseudomonas sp. isolate K24pf, K29pf, K32pf, K33pf and K37pf. From the 5 potential isolates, Pseudomonas sp. isolate K29pf was chosen because it showed potential activity in producing marked amounts of Indole-3-Acetic Acid and gibberellic acid. Pseudomonas sp. isolate K29pf also produced antimicrobial activities towards Ralstonia solanacearum, Erwinia caratovora, Erwinia mallotivora and Colletotrichum gloeosporioides. Seed germination test showed that Pseudomonas sp. isolate K29pf was able to promote approximately 90% growth of Brassica chinensis seeds. Pot trial conducted showed that Treatment 3 (+OF+PGPR) was able to increase Brassica chinensis root by 36.5% and 28.4% of its biomass compared to treatment using Treatment 1 (+OF).