Phosphites associated to fungicides fordiseases control and sanity in corn seeds

Abstract

The objective of this study was to evaluate the association of phosphites with fungicides and foliar fertilizers for the control of corn seed fungal diseases. The first is the evaluation of the potential of the copper, potassium and manganese phosphites at  the mycelial growth of the isolates of Fusarium verticilliodes and Fusarium graminearum, used doses was 0; 0.2; 0.4; 0.6; 0.8 and 1 L / 100 kg of seeds dissolved in BDA medium. The second phase of the study, the incidence of fungi was verified in seeds treated with Carbendazim + Thiram, Fludioxonil + Metalaxyl-m, Potassium Phosphite, Cooper Phosphite, Full Tec and Pack Seed, at doses of 1,5; 3.0; 1; 1; 2 and 3 mL-1  100 kg of seeds, respectively. Seed treatment was done manually using a graduated pipette and a 500 ml Becker, mixing them and homogenizing in a plastic bag. The results indicated that, the evaluation of mycelial growth, it was verified that for the fungus F. verticilliodes, the best treatment controlled the radial growth of the pathogen at the nine days of evaluation, were the treatments using potassium phosphite at doses of 0, 4; 0.6 and 1 mL, and Mn phosphite at the 1 mL dosis. For Fusarium graminearum, the doses and products that reduced the growth of the fungus were Phosphite of K and Mn, in the concentrations of 0.2 to 1 mL-1  100 kg of seeds. The fungi involved in the test were Fusarium verticilliodes, Penicillium sp., Rhizopus sp., Trichoderma sp., Aspergillus sp. Nigger, and Cercospora  sp.  the  results  showed that the phosphites in association with fungicides, demonstrate a positive effect on the health of corn seeds, nullifying the incidence of this fungus.