Characteristics of the growth and development of Guava fruit cultivated in plastic house were studied in relation to various pinching and defoliation treatments. 1. The growth curve of guava fruit assumed a double sigmoidal shape and the fruit matured at 20-22 weeks after anthesis. 2. Only fructose and glucose were detected in the fruit, unlike sucrose. Large amounts of sugars and vitamin C accumulated during the latter period of fruit development. The contents of some of the chemical

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... of mature fruit were 2.5-3.0 mg/l00 ml for fructose, 2.0-2.5 mg/l00 ml for glucose and 150-250 mg/100g FW for vitamin C. 3. Fruit weight and the content of some of the chemical components of fruit increased by the pinching treatment when four leaves remained at the upper part of the fruit position on the branch. On the other hand, pinching at the fruit position and defoliation of all leaves at the lower part of the fruit position on the branch decreased the fruit weight and the content of some of the chemical components of fruit. The results obtained suggest that the leaves around the fruit mainly contribute to fruit growth and the accumulation of chemical components. Therefore, the pinching treatment in which some leaves remained at the upper part of the fruit position enabled to produce Guava fruits with a higher quality.