Development of a new technique to produce winter cherimoyas.

摘要

This paper describes a novel technique to produce cherimoya (Annona cherimola) fruit during the winter season. In a controlled experiment the trees were encouraged to flower out of season by pruning them back severely in January, followed by tipping the newly emerged shoots together with the removal of apical leaves on either 1 or 15 June. Both dates were highly successful because all tipped shoots produce a second bloom in July. On average, four flowers per shoot were produced in the new growth in response to defoliation treatments. The second blooming lasted no more than 2 weeks. Late-forming flowers were hand pollinated and gave rise to fruit of high quality about 50 d later than an ordinary crop. A yield of 13 t.ha-1 was produced, with no significant differences between treatments. Postponing hand defoliation by 15 days delayed the harvest period 15 to 20 days, but no other effects on fruit set and quality were noted. Fruit harvested in December and January did not show chilling injury and reached full flavor. Number of seed per fruit, and consequently fruit size, was often increased in out-of-season cherimoyas. Late fruit suffered less preharvest drop than an ordinary crop. This work shows the possibility of producing high-quality cherimoyas during winter when the cherimoya fruit is in great demand.