Patogenicidade de Rhizopus stolonifer em frutos de mamão em diferentes temperaturas

Abstract

Papaya (Carica papaya L.) is a crop that stands out due to its nutritional and economic importance, is fast developing and easy propagation, resulting in high productivity. However, in the papaya postharvest diseases are major causes of loss of profitability, and are among the major rots, for example, caused by the fungus Rhizopus sp. This study aimed to evaluate the pathogenicity of the fungus Rhizopus stolonifer in papaya fruits at different temperatures. The isolate of Rhizopus pathogenicity used in the experiment was isolated from papaya fruits containing mature signs and symptoms of fungal infection. The pathogenicity of the fungus was tested by peeling disc replacement of ripe fruit by discs of mycelia and spores of Rhizopus stolonifer. The pieces of papaya seedling were placed in climate chambers and those of BOD, at temperatures of 15, 20, 25 and 30° C. The pathogen has developed both as witnesses in the pieces of papaya inoculated at temperatures of 20 and 25 degrees C, lower development occurring at 15 °C and no growth at 30° C. Therefore, one can conclude that the temperature affects the development of the pathogen in papaya fruits, indicating that the incidence and severity of disease occur at temperatures of 20 and 25°C.