Isolation and characterization of Plant Growth Promoting Rhizobacteria and their effects on growth of tomato seedlings

LOBATO-URECHE, M; PICCOLI, P; ORTIZ, R; COHEN, A C; PÉREZ-RODRIGUEZ, M; BOTTINI, R 1

Foz do Iguaçu

Simposio; XVI Symposium on Biological Nitrogen Fixation with Non-Legumes, IV LatinAmerican Workshop of PGPR, XIX RELARE; 2018

Nowadays the use of Plant Growth Promoting Rhizobacteria (PGPR) is considered acomponent for sustainable agriculture. The efficiency of inoculation depends of factors such as plant species, soil type, inoculum density, and environment conditions. Native bacteria are better adapted to a local plant and its environment than exogenous microorganisms. On the other hand tomato (Solanum lycopersicum L.) is one of the most important horticultural crops worldwide and Mendoza is the major producer in Argentina. However, there is little information available regarding the use of rhizobacteria in this crop. The aim of this work was to isolate and characterize PGPR at different soil depths from roots and rhizosphere of tomato crops, and to study the effect of inoculation with selected PGPR isolates on growth of tomato seedlings in order to reduce the fertilizer?s rates. After isolation and characterization according to theirPGPR characteristics, 5 bacteria strains were selected. All of them were able tosolubilize phosphate, produce siderophores, fix nitrogen and tolerate high NaCl. Then, a seedbed experiment was conducted in growth chamber with 15-days-old tomato seedlings inoculated at the root level. The seedlings were inoculated with the strains 25X1, 64S1, 53F, 42P4, 60I1, inoculation buffer alone (control without bacteria) and NPK (18:18:18; control fertilized). Inoculation with all bacteria increased (p