MOLECULAR IDENTIFICATION OF MICROORGANISMS ASSOCIATED TO THE RHIZOSPHERE OF VANILLA AND THEIR POTENTIAL USE AS BIOFERTILIZERS

Abstract

Abstract The cultivation of vanilla (Vanilla planifolia) is highly promissory in Colombia, where advances in crop management techniques is needed. This study describes vanilla rhizosphere microorganisms in functional groups, their molecular identification, and explores their potential use as biofertilizers. Under in vitro conditions, the most effective phosphate solubilizer was a bacterium with phylogenetic proximity to Serratia sp. followed species related to Pseudomonas saponiphila and P. koreensis. Pseudomonas sp. are among nitrogen fixing bacterium that are more abundant and fast growing. The most effective cellulolytic was a fungus phylogenetically related to Penicillium gliseofulvum followed by another isolate related to Aspergillus fumigatus. Among the five most effective proteolytic were three bacteria phylogenetically related to Bacillus mycoides and B. cereus, a bacterium related to Serratia sp. and another associated to B. thuringiensis. The most relevant phytate degrader were two isolates related to Acremonium sp. and Plectosphaerella sp. The results of this study show the high diversity of rhizosphere microorganisms in vanilla plants, some of them exhibit capacity for enhancing plant nutrients availability and, consequently, they have the potential to be used as biofertilizers.