CARACTERIZAÇÃO MORFOLÓGICA DE Fusarium spp. DO FEIJÃO FAVA E CONTROLE BIOLÓGICO VIA SEMENTES-PLÂNTULAS

Abstract

The management of plant diseases should take into account the etiology of the causal agent for the selection of appropriate practices. Currently, the main form of pathogen control in plants is through chemical control, causing concern, offering human health risks and the environment. Therefore, the objective of the work is to identify the biological interactions between antagonist and pathogen, as well as to develop effective strategies for control of rot and fusarium wilt in bean culture. Two isolates of Trichoderma spp. derived from the Mycological Collection of LAFIT, and ten isolates of Fusarium spp. seeds of bean. Bean bean seeds obtained from cultivated areas in the municipalities of Remígio, Alagoa Grande and Campina Grande, in the state of Paraíba. In vitro tests of direct comparison and volatile compounds between the antagonist and the pathogen were carried out. All isolates showed antagonism in vitro against the pathogen. Considering the growth promoter characteristics of Trichoderma, for the evaluation of the physiological quality, in the concentrations of 1,5; 2.0; 2.5 and 3.0 x 10 8 conidia / ml -1 of the antagonist when analyzing the interference in the germination and vigor of fava bean seeds. The Trichodel® isolate presented the highest normal seedling lengths. After inoculation, it was possible to observe symptoms of necrosis in the primary root and vascular dimming at 21 days. For the characterization, a total of 10 isolates were described morphologically in the BDA and SNA media, presenting a wide morphological variability.