FUNGICIDES IN SEED TRATMENT OF BEANS TO CONTOL DAMPPING OFF CUSED BY RHIZOCTONIA SOLANI

Abstract

THE SEEDLING DAMPPING OFF, CAUSED BY RHIZOCTONIA SOLANI, IS CONSIDERED ONE OF THE MOST IMPORTANT DISEASES IN THE EARLY STAGE OF THE BEAN. THIS SOIL-DWELLING PATHOGEN SURVIVES ON ORGANIC MATTER OR PLANT DEBRIS AND CAN BE TRANSMITTED TO THE SEEDS. THE OBJECTIVE OF THIS WORK WAS TO VERIFY THE EFFICIENCY OF THE USE OF FUNGICIDES IN THE TREATMENT OF P�ROLA BEAN SEEDS, AIMING THE CONTROL OF SEEDLING DAMPPING OFF CAUSED BY RHIZOCTONIA SOLANI. THE TREATMENTS USED WERE: 1) CARBENDAZIM + THIRAM; 2) CARBENDAZIM + THIRAM + (FLUDIOXONIL + METALAXYL-M); 3) FLUDIOXONIL + METALAXYL-M; 4) PYRACLOSTROBIN + THIOPHANATE METHYL; 5) PYRACLOSTROBIN + METHYL THIOPHANATE + (FLUDIOXONIL + METALAXYL-M); 7) CARBENDAZIM + THIRAM; 8) CARBENDAZIM + THIRAM + (FLUDIOXONIL + METALAXYL-M); 8) TRICHODERMA ASPERELLUM. UNTREATED AND TREATED WITH FUNGICIDE SEEDS WERE SOWN IN SAND CONTAINED IN PLASTIC TRAYS. THE INOCULATION WITH R. SOLANI WAS DONE USING 80 G OF THE INOCULUM (SORGHUM SEEDS COLONIZED BY R. SOLANI) PER TRAY, DISTRIBUTED IN THE SEEDING GROOVES. THE EMERGENCE OF SEEDLINGS AT 07 AND 15 DAS AND THE EMERGENCY SPEED INDEX WAS EVALUATED. SEEDLING EMERGENCE WAS REDUCED IN INFESTED SOIL. AT SEVEN DAS, ALL PRESENTED A SIGNIFICANT DIFFERENCE WHEN COMPARED TO THE INFESTED CONTROL WITH THE EXCEPTION OF THE TRICHODERMA ASPERELLUM TREATMENT. THE TREATMENTS T1 (CARBENDAZIM + THIRAM), T3 (FLUDIOXONIL + METALAXYL - M) AND T4 (PYRACLOSTROBIN + THIOPHANATE METHYL) WERE EFFICIENT IN CONTROLLING R. SOLANI AT 15 DAS. FOR EMERGENCIES AT 7 AND 15 DAS AND IVE THE TREATMENTS WERE EQUIVALENT WHEN COMPARED TO EACH OTHER.