Rhizoctonia aerial blight (RAB), caused by the fungus Thanatephorus cucumeris is one of the most damaging diseases of soybean at Roraima, Brazil. The objective of this study was to evaluate the reaction of 15 soybean cultivars to RAB in a cerrado (savannah) ecosystem in the state of Roraima. The percentage of foliar area infected (FAI) and the percentage of pods with disease symptoms (WP) were evaluated on soybean plants at R.5.5 and R.6 growth stages, respectively. There were significative differences among cultivars tested based on Fisher LSD test in both evaluations. The FAI ranged from 1.5% (cv. Padre) to 62% (cv. BR-36) and WP from 8% (cv. UFV-9 and cv. Juçara) to 55 % (cv. BR-36). Significative and positive correlation was observed between the evaluations.
Glycine max; Rhizoctonia solani; Amazon
