Radiação e condições de temperatura pré colheita determinam a suscetibilidade dos frutos do tomate a danos causados pelo frio pós-colheita

Abstract

ABSTRACT The aim of this work was to improve the understanding about the relationship between solar radiation and temperature exposure during crop and tomato fruit susceptibility to postharvest chilling injury. Two preharvest treatments were applied: direct sunlight exposed plants (Ex) and shaded plants (Sh). After harvest, fruit were stored at 10⁰C and 4⁰C for ten days. Then, fruit were removed from the chambers and stored at room temperature for four days. Several determinations were carried out: total mineral and calcium content, fruit quality and postharvest parameters, ions leakage and thiobarbituric acid reactive species content and chilling injury index (CII). Ex fruit had higher values of chilling injury index than the Sh fruit, and at the same time, fruit under 4⁰C storage treatment presented a more marked damage than those stored at 10⁰C, demonstrating that accumulated radiation in the field, as a result of a higher solar radiation exposure, is a critical factor affecting postharvest chilling injury susceptibility. The lower calcium content in the Ex fruit could be one of the causes of their response to chilling.