Ripening physiology and respiration pattern of guava, papaya and passion fruit

• Grant number: 09/13698-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2009
• End date: December 31, 2012
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Angelo Pedro Jacomino
• Grantee: Ana Elisa de Godoy
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Climacteric fruits are characterized by increased CO2 production, followed by an autocatalytic ethylene peak, which is not observed in non-climacteric fruits. Recent research has shown that some ripening processes are not related with the increase in respiratory activity and the climacteric also depends on factors such as harvest time and pre-harvest factors. These studies show that some fruits do not fit the classical definitions of the pattern of respiratory activity. The objective of this study is to determine the respiratory pattern and to characterize the ripening physiology of 'Pedro Sato' guava, 'Golden' papaya and yellow passion fruit attached to or detached from the plant and to determine the effects of exogenous ethylene and 1-methylcyclopropene (1-MCP) on these fruits ripening. Will be carried out the estimate the endogenous CO2 and ethylene concentration in guava, papaya and passion fruit attached to or detached from the plant. These tests will be carried out since the beginning of fruit development until senescence of them. In another step, guava, papaya and passion fruit will be harvested at three ripening stages from commercial fields and ethylene and 1-methylcyclopropene (1-MCP) will be apply on the fruits to determine their effects on the physiology and quality of these fruits. At this step, will be analyzed physiology (respiration rates and ethylene production), physical-chemical characteristics (water loss, skin color, firmness pulp, soluble solids, titratable acidity and ascorbic acid), and biochemistry (ACC (1-aminocyclopropane-1-carboxylic acid) oxidase activity). The experimental designs will be completely randomized and in factorial experiments and the results will be submitted to ANOVA and Tukey's test and descriptive statistics, as appropriate. (AU)