Injuries in 'Valência' oranges cultivated in organic and conventional systems

Abstract

The organic plantation of citrus comes increasing annually, searching to take care of the increasing demand for healthful foods and sustainably produced. This study aimed to characterize the injuries of biotic (diseases and pests) and abiotic origin (mechanical damage and physiological disorders) in fruits of 'Valencia' orange collected in orchards of organic and conventional crops in two locations (Borborema and Itápolis, State of Sao Paulo), as well as in organic 'Valencia' orange commercialized in the Companhia de Entrepostos e Armazéns Gerais de São Paulo (Ceagesp). Fruits were evaluated visually for the incidence of injuries and stored during 14 days at 25 ºC and 85% of UR, when were evaluated the increase in the incidence of black spot citrus (BSC) and of dehydrated fruits. The MPC was the main disease affecting more than 50% in the sampled fruits in the orchards and with an average increase of 17% after storage. The incidence of melanose was higher in organic fruits, however, for the other diseases the results varied in relation to the cropping system in the localities. The incidence of symptoms of pesticide phytotoxicity was higher in fruits from the conventional system. Five species of scale insects were observed, especially black parlatore, with incidences ranging depending on the farming system in the localities. Major damage by hopes were observed in organic fruits, while the damage by citrus borer and fruit fly were low (<2%) and similar between cropping systems.