Controle da antracnose em banana com aplicação de formulações de fosfito

Abstract

The objective of the first chapter was to evaluate the in vitro effect of different formulations and concentrations of phosphites on the development of Colletotrichum musae. In the second chapter, the objective of this study was to evaluate the efficiency of the application of different phosphite formulations applied to banana curls in two application frequencies, on the incidence and severity of the anthracnose in banana 'Ananas' and physical and chemical characteristics of the fruits. The third chapter had as objective to evaluate the effect of the post-harvest application of different formulations of phosphite in different concentrations in the control of the anthracnose and in the physical and chemical characteristics in banana fruits 'Prata anã'. In the evaluation of inhibition of mycelial growth, sporulation and germination, three different phosphites were used: FCu1 (4% Cu + 20% P2O5), FCu2 (4% Cu + 22% P2O5) , 0; 1.5 and 2.0 mL L1 and FK (42% P 2 O 5 + 27.7% K 2 O) at the concentrations of 0.5; 1.0; 1.5 and 2.0 mg. L-1. The products were incorporated into the respective culture media. The culture medium and the culture medium + Imazalil were used as controls. In the second chapter, different sources of FCu1 phosphite (4% Cu + 20% P2O5), FCu2 (4% Cu + 22% P2O5) and FK (42% P2O5 + 27.7% K2O) pure and control (no treatment) were applied to the 'Prata anã' banana bunches during field development in two application frequencies: 15 in 15 days and 30 in 30 days. The fruits were harvested, stored in a refrigeration chamber (25 ± 1 ° C and 80 ± 5% RH) and evaluated for the incidence and severity of anthracnose. In the third chapter, different sources of copper phosphite FCu1 (4% Cu + 20% P2O5), FCu2 (4% Cu + 22% P2O5) and potassium FK (42% P2O5 + 27,7 % of K2O) in different concentrations 0.5; 1.0, 1.5 and 2.0 mL L1. The first study was carried out in a 3 x 4 + 2 factorial arrangement consisting of three different phosphites: FCu1 (4% Cu + 20% P2O5), FCu2 (4% Cu + 22 % of P2O5) and FK (42% of P2O5 + 27.7% of K2O), in the concentrations 0.5; 1.0; 1.5 and 2.0 mL L-1 and two control treatments that corresponded to the culture medium and the culture medium + Imazalil. The products were incorporated into the respective culture media. In the second study, the 3 x 2 + 2 factorial arrangement was used again, as a treatment for the three different phosphite formulations: FCu1 (4% Cu + 20% P2O5), FCu2 (4% Cu + 22% P2O5 ) and FK (42% P2O5 + 27.7% K2O) at the concentrations of 1.5 mL.L-1 water for the FCu1 and the FCu2 and 1.5 grams. L-1 of water for the FK, the witnesses consisted of the application of water and the absence of application of the products. The products were applied in banana shoots 'Prata anã' during field development in two application frequencies: 15 in 15 days and 30 in 30 days. The results observed in chapter one showed a significant fungistatic effect between the concentrations of the products in the mycelial growth, sporulation and germination obtaining control of up to 100% of the development of Colletotrichum musae. In chapter two it was verified that the FCu2 reduced the incidence of the anthracnose by up to 38% and the severity 49.5%. Analyzing the frequencies of application of the phosphites, it is verified that they do not interfere in the intensity of the anthracnose. The application of phosphites in banana 'Banana' bananas increases the loss of fresh pasta. For the chemical and physical variables, there was no difference between the phosphite sources and the application frequencies. In chapter three it was possible to conclude that FCu2 controlled the incidence of anthracnose by up to 38% and the severity of 49.5%. Frequencies of application of phosphites do not interfere with the intensity of anthracnose. The application of phosphites in banana 'Banana' bananas increases the loss of fresh pasta. For the other chemical and physical characteristics, there was no consistent difference between the phosphite sources and the application frequencies.