BIOFERTILIZATION WITH RHIZOBACTERIA AND A CONSORTIUM OF ARBUSCULAR MYCORRHIZAL FUNGI IN CITRUS ROOTSTOCKS

Abstract

The effect of individual and combined biofertilization with the plant growth promoting rhizobacteria (PGPR) strains FCA-8, FCA-56 and FCA-60 of Pseudomonasputida and arbuscular mycorrhizal fungi (AMF) on the growth of Citrus volkameriana and Rangpur lime rootstocks grafted with Tahiti lime was evaluated under nursery conditions. Plants were inoculated individually and combined with the three rhizobacterial strains and with AMF, and received 50% fertilization. These plants were compared with a control group that received nursery management with 100% fertilization. A 2 x 10 factorial split-plot experimental design with five replications per treatment was established. Variables measured included plant height, stem-base diameter, root length and volume, fresh and dry plant biomass, and bacterial and mycorrhizal colonization. Individual and combined biofertilization with PGPR and AMF promoted the growth of C. volkameriana and Rangpur lime grafted with Tahiti lime in the nursery, similar to the control with 100% fertilization. The three strains of P. putida and AMF applied individually or combined provided similar results to the control in the nutrient content of Tahiti lime leaves. The P. putida strains showed good capacity for colonization of the rhizosphere of C. volkameriana and Rangpur lime individually or combined with AMF.