Viability of the sugar apple (Annona squamosa) pollen grains at different hours of the day

In the management of the sugar apple (Annona squamosa) crop, the artificial pollination is a preconized practice to obtain higher establishment of the fruits as well as their standardization. This study was carried out to evaluate the viability of sugar apple pollen grains at different collecting times. The pollens were obtained from the flowers at the functional staminate stage. The pollen grains were collected every hour, starting from 00:00am and ending at 07: 00am, totalizing 8 collections. The standard culture medium with 10% sucrose was used for the germination of the pollen. The flowers were collected at the scheduled hours and the pollen grains were taken from the anthers, by using a brush # 2. They were then inoculated on Petri dishes containing the culture medium. The completely randomized experimental design was used with four replicates, and each plot was constituted by two Petri dishes. One hundred pollen grains were counted in each Petri dish. After six hours of inoculation, the pollen grains were visualized under magnifying glass. Those pollen grains containing the pollinic tube with the same or higher size than their own pollen diameter were considered germinated. No significant differences were found among the different hours of the pollen grain collections, and the germination percentage ranged from 46.75% to 53.62%.