Exploring the Phytobeneficial and Biocontrol Capacities of Endophytic Bacteria Isolated from Hybrid Vanilla Pods

In this study, 58 endophytic bacterial strains were isolated from pods of two hybrid vanilla plants Madagascar, Manitra ampotony and Tsy taitra. They genetically characterized divided into four distinct phylotypes. Three associated to genus Bacillus species, the fourth Curtobacterium. A selection twelve corresponding identified genetic diversity tested in vitro for phytobeneficial capacities: phosphate solubilisation, free nitrogen fixation, phytohormone siderophore production. also evaluated their ability biocontrol growth pathogenic fungi, Fusarium oxysporum f. sp. radicis vanillae Cholletotrichum orchidophilum. bacteria phylotype 4, m62a, m64 m65, showed a high fixation capacity vitro, similar Pseudomonas florescens F113 bacterium used as control (phospate solubilizing efficiency respectively 0.50 ± 0.07, 0.43 0.07 0.40 0.06 against 0.48 0.03). Strain t2 related B. subtilis higher production than (respectively 1.40 0.1 AU 1.2 AU). The strain m72, with 2, highest rate Indole-3-acetic acid (IAA) vitro. Bacteria belonging pylotype 4 best inhibit fungal growth, especially m62b t24, which induced significant zone inhibition, suggesting that they may be good candidates controlling diseases vanilla. This competence was highlighted spectral imaging showing lipopeptides (Iturin A2 A3, C16 C15-Fengycin C14 C15-Surfactin) by m65 confronted fungi