Aspectos epidemiológicos e manejo da antracnose em morango com radiação gama

Abstract

Anthracnose is a major post-harvest diseases of strawberry, causing various losses and limiting the quality of the fruit. Besides the lack of studies on climatic conditions that favor the disease, lack of active ingredients registered for the management of the disease in Brazil defines the need to search for alternative control. This study aimed to study the influence of inoculum concentration, temperature and leaf wetness period and to evaluate the effect of gamma radiation on the severity of anthracnose caused by Colletotrichum acutatum in postharvest strawberry, and influence of this treatment on the physical attributes -chemical such as pH, total soluble solids (TSS), titratable acidity (TA) and TSS / TA. Inoculum concentrations tested were 102, 10³, 104, 105,106 and 107 spores / mL, for the fruits wet period were submitted to: 0, 12, 24, and 36 h of incubation, the influence of temperature on disease severity The fruits were incubated under controlled temperature for 12, 15, 20 and 25 ° C. In the control fruits with gamma radiation received doses: 0.25, 0.50, 0.75, 1.0, and 1.25 kGy in two stages: immediate and six hours after the inoculation of the fungus. The control treatment did not receive doses of gamma radiation. Disease severity was significantly influenced by the higher concentration of inoculum (107 spores / ml), incubation temperature and the wetness of the fruit, with larger lesions in the fruits exposed to 25 ° C and 36 h. The irradiation the best treatments were performed immediately after inoculation, highlighting the dose of 1.25 kGy. Treatment with gamma radiation did not alter the chemical characteristics of fruits analyzed in this study. Thus, these treatments can be given for the post-harvest treatment of strawberry.