EFFICIENCY OF SYSTEMIC FUNGICIDE WITH MULTISITES TO CONTROL ASIAN SOYBEAN RUST

Abstract

SOYBEAN CULTIVATION HAS BEEN MAINTAINING THE GROWING TREND IN THE CULTIVATED AREA AND, IN THIS 2018-2019 CROP, THE ESTIMATE POINTS TO GROWTH OF 2.3% OVER THE PAST CYCLE, PRODUCING 120.9 MILLION TONS. ASIAN RUST IS A DISEASE CAUSED BY THE BASIDIOMYCETE FUNGUS PHAKOPSORA PACHYRHIZI, ORIGINATING FROM AUSTRALIA, THIS DISEASE CAME TO BRAZIL IN 2001. BECAUSE IT HAS A HIGH DESTRUCTIVE POTENTIAL FOR SOYBEAN CULTIVATION IN ALL COUNTRIES WHERE IT WAS DETECTED. CURRENTLY CONSIDERED THE MAIN PROBLEM. TO BE FOUGHT BY BRAZILIAN SOYBEAN FARMERS, ASIAN RUST HAS BEEN THE TARGET OF EXHAUSTIVE CONTROL ATTEMPTS, ENVIRONMENTAL CONDITIONS FAVOR THE OCCURRENCE OF THE DISEASE. P. PACHYRHIZI INCIDENCE ASSESSMENTS WERE PERFORMED AT: STAGE V4; V6; R1 / R2; R1 / R2 + 14 DAYS; R1 / R2 + 28 DAYS; R1 / R2 + 42 DAYS AND R1 / R2 + 49 DAYS FOR YIELD OF THE AREA UNDER THE P. PACHYRHIZI SEVERITY DATA PROGRESS CURVE (AACPD) IN SOYBEAN. AT HARVEST (R9) THE AVERAGE PLANT HEIGHT WAS EVALUATED, USING FOUR PLANTS PER PLOT, THE HARVESTED AREA WAS 4M2. AFTER HARVESTING THE PLANTS WERE MANUALLY TRACKED AND ESTIMATED YIELD IN KG.HA-1 WITH 13% MOISTURE IN THE GRAIN, AND THEN ESTIMATING THE WEIGHT OF 1,000 GRAINS. THE SEVERITY PERCENTAGE EVALUATIONS WERE PERFORMED BY THE DIAGRAMMATIC SCALE FOR ASIAN RUST. IT WAS CONCLUDED THAT THE TREATMENTS SPM + DIFFER, SPM + PREVINIL 720, SPM + MANFIL 800 WD, SPM + FEZAN GOLD, SPM + ELEVE, SPM + NILLUS, SPM + BRAVONIL 720 SC REFLECTED SIMILARLY ON CROP YIELD. REGARDING THE WEIGHT OF ONE THOUSAND GRAINS, ALL TREATMENTS WERE STATISTICALLY SIMILAR, BEING SUPERIOR ONLY TO THE CONTROL WITHOUT CONTROL. THE APPLICATIONS OF SPM + BRAVONIL 500 SC, SPM + UNIZEB GOLD, AND SPM + PREVINIL 720 SC PRESENTED LOWER AACPD DISEASE SEVERITY INDEX.