AJCS 13(09):1467-1472 (2019) ISSN:1835-2707 doi: 10.21475/ajcs.19.13.09.p1557 Phenological study of sugar apple (Annona squamosa L.) in dystrophic yellow latosol under the savanna conditions of Roraima Elias Ariel de Moura1*, Pollyana Cardoso Chagas2, Edvan Alves Chagas3, Railin Rodrigues de Oliveira2, Wellington Farias Araújo2, Sara Thiele Moreira Sobral2, Daniel Lucas Lima Taveira2 1Universidade Federal Rural do Semi-Árido, Programa de Pós-Graduação em Fitotecnia, Av. Francisco Mota, 572, Costa e Silva, 59.625-900, Mossoró, RN, Brasil 2Universidade Federal de Roraima, Centro de Ciências Agrárias, Departamento de Fitotecnia. Boa Vista/RR, Brasil 3Empresa Brasileira de Pesquisa Agropecuária, Boa Vista, RR, Brasil. CNPq Research Productivity Scholarship. *Corresponding author: [email protected] 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. Keywords: Amazon; Reproductive behavior; Vegetative behavior; Annona squamosa L; Cultivation periods. Introduction Sugar apple (Annona squamosa L.), also known as custard Northern Brazil has a great fruticulture potential to grow apple and sweet-sop, is adapted to different soil and climatic tropical and subtropical species. In northern Brazil, the state conditions, which favored its worldwide expansion. The of Roraima has increasingly focused on the production of species is native to tropical America, particularly to the several fruit species owing to its climatic peculiarities. Antilles, and can be cultivated in tropical and subtropical However, few studies on the phenological behavior of these areas (Liu et al., 2015). Sugar apple has been commercially species under the savanna conditions of Roraima have been cultivated in Africa, South America, Australia, India, Mexico, reported in the literature, which hinders the expansion of in the south and the United States, the Philippines, and crops with productive potential, such as sugar apple. Thailand (Pinto et al., 2005; Crane et al., 2016). For being a To obtain production quality and increase the profitability of large country, Brazil can produce high yields when compared sugar apple crops, management techniques must be with other producing countries, especially in the states with employed, such as: floral induction, artificial pollination, hot climate, little rainfall, and a well-defined dry season irrigation and fertilization, phytosanitary treatment, weed during the year (Lederman and Bezerra, 1997) control, fruit thinning, harvest maturity, and post-harvest A. squamosa is of great commercial importance and stands strategies, among other practices already used by more out among other species in the genus Annona due to its technified producers (Salvador, 2013; São José et al., 2014). medicinal and nutritional properties, such as vitamins A, B, However, to apply such techniques, a previous phenological C, E, K1, antioxidants, polyunsaturated fatty acids, and study of the vegetative and reproductive behavior of the essential minerals, besides its pleasant aroma and flavor (Liu species is necessary since the phenophase is influenced by et al., 2013; Liu et al., 2015). Despite being mainly consumed the different edaphoclimatic conditions of each region. in natura, sugar apple can be used to produce juices, Phenology is defined as the study of the cyclical phenomena candies, ice cream, liqueurs, and pharmacopeia. of the plant in function of the relations with the 1467 environment. This study is based on evaluations of visible Development of flowering development stages of the plants (phenophases), such as bud swelling, leaf development, flowering, fruit Under the savanna conditions of Roraima, the beginning of development, and senescence (Serrano et al., 2008). flowering of sugar apple plants occurred approximately two Thus, the phenological knowledge of the species under the weeks after production pruning with 17 days in 2014/2014; desired edaphoclimatic conditions enables crop 16 days in 2014/2015; 21 days in 2015/2015 and 20 days in management, cultural practice at the appropriate time, 2015/2016 after pruning (Table 2 and Figure 2 C). Similar allowing the advance or delay of fruit harvest, according to results were observed in a study carried out in São Francisco the demand of the consumer market. de Itabapoana-RJ. Santos et al. (2014) reported that pruning Therefore, this work aimed to study the vegetative and performed in September presents a shorter interval until the reproductive phenology of sugar apple under the savanna maximum flowering (15 days) when compared with pruning conditions in the state of Roraima. performed in May, June, July, and August (31, 86, 51, and 45 days, respectively). The longest period of 23 days between Results and discussion the production pruning and the beginning of flowering was observed by Dias et al. (2004) in Anagé-BA. Therefore, sugar Development of shoots apple plants behave differently depending on the region and present variations between each phenophase. This fact may The data referring to the phenological stages observed in influence the efficiency of the cultural techniques necessary sugar apple trees cultivated under the savanna conditions of for the cultivation of the species, such as artificial Roraima are presented by production cycle: February 2014 pollination, one of the most important techniques for the to July 2014; September 2014 to February 2015; February achievement of high yield and production quality. According 2015 to Agost 2015 and September 2015 to February 2016 to Nietsche et al. (2009), despite the large amount of flowers (Table 1). produced in each cycle, approximately 5 to 10% of fruits are The period (days) between the production pruning and the formed. beginning of bud swelling were of six days for 2014/2014, Under the conditions of the experiment, the end of ten days for 2014/2015, nine days for 2015/2015 and seven flowering was not observed in the evaluated cycles, i.e., days for 2015/2016 in the productive cycles observed (Table flowering was continuous during the evaluation period 2). (Table 1). A period of 34, 26, 32 and 40 days was recorded These differences can be attributed to the different climatic between the end of bud swelling and anthesis for the cycles conditions observed in each production cycle. These 2014/2014; 2014/2015; 2015/2015 and 2015/2016 variations in the meteorological elements, with a reduction respectively (Table 2). The periods observed in the present in the rainfall in the second cycle for 2014/2015 and experiment were superior to those reported by Dias et al. 2015/2014 being more attenuated, accompanied by a (2003), who registered 23 days from bud swelling to decrease in the relative humidity and a slight increase in the anthesis, with pruning carried out in February. Conversely, air temperature may have influenced the shorter period of the period between production pruning and anthesis was the 2014.2 cycle in the two years of cultivation (Tables 1; 2 40, 36, 41, and 47 days for the four cycles (Table 2 and and Figure 1). Figure 2 H), respectively, under the savanna conditions of However, the periods between production pruning and the Roraima (Table 2). These intervals are similar to those beginning of bud swelling presented similar results when verified by Dias et al. (2003) and Dias et al. (2004), who compared with other Annonaceae producing regions. When reported 44 and 33 days, respectively, from pruning to studying the vegetative and reproductive performance of anthesis in Anagé-BA and Tanhaçu-BA, respectively. sugar apple plants in function of the different lengths of The development of the flower varies according to the pruned branches in Anagé-BA, Dias et al. (2004) registered climatic conditions of the region. Dias et al. (2003) stated ten days from production pruning to the beginning of bud that high temperatures tend to advance the development of swelling. However, under the climatic conditions of sugar apple flowers. Although the temperature in the state Zhanjiang-China, Liu et al. (2015) observed that bud swelling of Roraima