Phenological study of sugar apple (Annona squamosa L.) in dystrophic yellow latosol under the savanna conditions of Roraima

Abstract

Sugar apple (Annona squamosa L.) is a commercially significant fruit species due to its nutritional qualities. The state of Roraima has excellent soil and climatic conditions for the cultivation of the species. However, no studies on the phenological behavior of this plant have been reported in the literature. In this context, the objective of this work was to investigate the vegetative and reproductive phenological behavior of sugar apple under the savanna conditions of the state of Roraima. The experiment was carried out in four seasons of the year (2014/2014 and 2015/2015 rainy season and 2014/2015 and 2015/2016 Summer). Production pruning was carried out in February 2014 (2014.1 cycle), September 2014 (2014.2 cycle), February 2015 (2015.1 cycle) and September 2015 (2015.2 cycle). Forty plants were monitored during the experiment and evaluated every three days for the following variables: beginning date of bud swelling; duration of flowering; and fruit harvest time. From the observed data, the periods (days) between each phenological stage were calculated: pruning/bud swelling; pruning/beginning of flowering; bud swelling/anthesis; pruning/anthesis; anthesis/beginning of fruit harvest; duration of fruit harvest, and crop cycle (production pruning/harvest). The duration of the cycle, from the production pruning to the harvest varied according to the productive period, recording 146 days for the 2014.1 cycle and 127 days for the 2014.2 cycle, which proves that the phenological behavior of the species is influenced by climatic conditions.