INDUCTION OF RESISTANCE TO Colletotrichum truncatum IN Phaseolus lunatus BY NON-PATHOGENIC ISOLATE OF Fusarium spp. and Rhizobium spp.
Endophytic microorganisms; Plant disease control; Anthracnose.
The resistance induction process is the previous activation of the plant's defense mechanisms by biotic or abiotic agents. Induced defense processes can be of two types: acquired systemic resistance (SAR) or induced systemic resistance (ISR). ISR is activated by a microorganism from the rhizosphere and isolates of Fusarium oxysporum and Rhizobium etli have already been characterized as resistance inducers in several cultures. This work aimed to verify the effect of Fusarium spp. and Rhizobium spp. obtained from Phaseolus lunatus in the activation of the defense response against the causal agent of anthracnose, Colletotrichum truncatum. The experiment began with obtaining isolates of Fusarium spp. non-pathogenic and Rhizobium spp., after that the morphological characterization was carried out, the evaluation of the direct antibiosis of Fusarium spp. and Rhizobium spp. in relation to Colletotrichum truncatum. The selection of material for analysis of resistance enzymes was made from production experiments (weight of fresh and dry matter of shoot and root and evaluation of resistance), then the analysis of peroxidase and phenylalanine ammonia-lyase enzymes was performed. The results were submitted to analysis of variance at 5% probability and the Scott-Knott test (p = 5%). Isolates of Fusarium spp. FF 11.1 and FF 3 and the isolate B. Nelita from Rhizobium spp. were able to reduce disease severity and induce resistance.