HIGH-TEMPERATURE EFFECTS ON CHERIMOYA FRUIT-SET, GROWTH AND DEVELOPMENT UNDER GREENHOUSE CONDITIONS

The effects of warm (30/25 degrees C) and cool (20/15 degrees C) day/n ight temperatures on fruit set and fruit growth of potted cherimoya (A nnona cherimola Mill.) trees were investigated under sunlit glasshouse conditions. Pollen germination percentage was adversely affected by w arm temperatures. Fruit set at warm temperatures was very low, ascribe d to both pollen and stigmatic damage from heat stress, although the f ormer was more sensitive to warm temperatures than female organs. Frui t at warm temperatures grew slowly and required more days to mature th an those at cool temperatures. Warm temperatures reduced fruit growth rates at the initial and final growth stages. The intervening growth d eceleration period was longer at warm temperatures. Warm temperatures produced asymmetrical and small fruit containing a small number of see ds, caused by low-viability pollen. Temperature had no significant eff ect on the total soluble solid content in fruit. (C) 1998 Elsevier Sci ence B.V. All rights reserved.