Tratamento químico e biológico em sementes de feijão inoculadas com Sclerotinia sclerotiorum e efeitos sobre qualidade sanitária e fisiológica

Abstract

Beans have great economic and social importance in Brazil, however, diseases such as white mold, reduce the production of this grain. The objective of this study was to evaluate the effect of chemical and biological treatment on the germination, vigor and health of bean seeds (cv. ‘IPR Tuiuiú) inoculated with Sclerotinia sclerotiorum by means of water restriction. The experiment was conducted in a completely randomized design with 4 replicates. The seeds were submitted to the following treatments: T1) fungicide; T2) Trichoderma asperellum (1.0 x 1010 conidia mL-1); T3) Trichoderma harzianum (1 x 109 CFUs); T4) Bacillus subtilis (1 x 109 CFUs); T5) Bacillus amyloliquefaciens (3 x 108 CFUs); T6) Positive Control (seeds exposed to the pathogen but not treated); T7) Negative Control + fungicide; T8) Negative Control + Trichoderma asperellum; T9) Negative Control + Trichoderma harzianum; T10) Negative Control + Bacillus subtilis; T11) Negative Control + Bacillus subtilis; T12) Negative Control (seeds not exposed to pathogen). After, the in vitro tests of germination speed index (GSI), germination, seedling length, cold test, accelerated aging and incidence of Sclerotinia sclerotiorum; and in vivo, green mass, dry mass and field emergence were evaluated. It can be verified that the inoculation of the seeds by means of the water restriction provides perfect infection. The inoculated seeds showed the best results and the fungicide is the best inoculated seed treatment, followed by treatments with Trichoderma asperellum, Trichoderma harzianum, Bacillus subtilis and Bacillus amyloliquefaciens.