Postharvest diseases and physicochemical characteristics in 'Valência' orange from organic and conventional farmers

• Grant number: 09/07357-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2009
• End date: June 30, 2010
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Ivan Herman Fischer
• Grantee: Michele Moraes Zanette
• Host Institution: Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

The organic plantation of citrus comes increasing annually, searching to take care of the increasing demand for healthful foods, produced without the use of pesticides. However, there are few studies about the influence of this type of management on the occurrence of pests and diseases and on the quality physical and chemical of the fruits. The purposes of this work are: to characterize postharvest diseases and the physical and chemical quality of the 'Valencia' orange fruits grown under organic and conventional conditions. Citric fruits will be collected monthly, during six months, in two organic and two conventional orchards, located in Borborema and Itapolis city, São Paulo state; characterized how much to the physical and chemical quality (mass, pulp content, soluble solids content, titratable acidity, ratio and ascorbic acid) and stored during 14 days at 25ºC and 85% of UR. The incidence of postharvest diseases will be evaluated visually every three days and the fungi isolated from fruit rot will have the pathogenicity confirmed through the inoculation in healthy fruits. The rot incidence, as well as the physicochemical characteristics, will be compared between the orchards, by the Tukey test, at 5% of probability. The results of postharvest diseases incidence will be correlated with the physical and chemical quality of the fruits.