The short guava shelf life is the main problem that affects commercialization of fruits, either in national or international markets. The 1-MCP is known as an ethylene blocker. This work was carried out to determine the effects of 1-MCP over attributes of quality of 'Kumagai' guavas. The guavas were harvested with the skin color changing from dark-green to light-green stage, presenting: firmness (N) 85 and skin color (h°) 117, without injuries. Fruits were exposed to 0, 100, 300, 900 nL.L-1 of 1-MCP for 3 hours. Later the fruits were kept in room temperature of 22±2 °C and 80-90 % RH for 12 days. The treatments delayed the skin color and firmness changes, and also delayed the increase of ascorbic acid and sugar; the weight loss, titratable acidity and incidence of rots were not affected. The respiratory rate and ethylene production were suppressed reaching the lowest values with the highest concentration of the product. The application of 1-MCP from 300 to 900 nL.L-1, during 3 hours, extended the shelf life of guavas 'Kumagai'.
Vegetal regulator; Psidium guajava; 1-MCP; ethylene; respiration
