Toualy Serge Thibaut OUINA^1,, Rosin Don Rodrigue VOKO Bi¹, Kouamé Claude YA¹, Pascaline Emira Wilfried KOUAMɹ, Marina KOUSSEMON-CAMARA², Ibrahim KONATE¹

Salinisation due to intensive agriculture and geological alteration reduces soil microbial activity, creating unfavorable conditions for plant growth. This study aimed at screening degraded banana plantation soils from Digbapia and Zokoguhé (Daloa, Côte d’Ivoire) for fluorescent Pseudomonas spp. able to tolerate saline stress. Isolates were recovered, assayed for extracellular enzymatic activities, and tested for growth across a NaCl and KNO₃ gradient up to 10%. Soil samples were collected from six degraded banana plantation sites. Fluorescent Pseudomonas spp. were isolated using culture techniques on media King’s A and B. Isolates were subsequently assayed for amylase, cellulase, protease and lipase activities and evaluated by monitoring growth in media supplemented with NaCl and KNO₃ at concentrations ranging from 0 to 10%. Eight Pseudomonas species coded C226, C211, C127, C213, C212, C112R, C2211 and C129 were isolated from these soils. Among these isolates, C112R and C226 showed amylolytic activity, while C212, C213 and C127 showed cellulolytic activity. For high concentrations (8 to 10%), in KNO₃ between 791.27 and 989 mM then in NaCl between 1368.9 and 1711.1 mM, the isolates able to grow were C129, C213, C127, C2211 and C112R. These species are the best candidates for resistance to salt stress. They could serve as plant biostimulants under saline conditions, contributing to soil restoration.

salinity, Pseudomonas, enzymes, degraded soil, agriculture