Bagging management and breeding strategy for red sugar apple (Annona squamosa L.)

'Taitung No.2' was the major cultivar of sugar apple (Annona squamosa L.) cultivated in Taiwan. Its fruit is big (800-1000 g) and has been cultured for more than 10 years locally. In order to diversify cultivars of sugar apple and expand new consumer markets, a study was conducted to develop production technique for red sugar apple. The peel color of the current cultivar of red sugar apple planted in Taiwan was dark red, which is not accepted by most consumers. The study used different color papers, including single-layer (yellow and black) and double-layer (yellow-black), to bag the fruit of red sugar apple during growth stage. Results indicated that all bagging treatments decreased light intensity inside the bag and reduced chlorophyll accumulation in peel. The yellow-black double layer bagging showed the lowest chlorophyll content and the highest anthocyanin/chlorophyll ratio in peel. The reddish peel color could increase attraction of consumers. According to the phenotypic ratios of hybrid offspring, there are at least two recessive genes that are involved in controlling the red coloration of red sugar apple.