Facultad de Ciencias ACTA BIOLÓGICA COLOMBIANA Departamento de Biología http://www.revistas.unal.edu.co/index.php/actabiol Sede Bogotá ARTÍCULO DE INVESTIGACIÓN / RESEARCH ARTICLE BOTÁNICA PHENOLOGY, BIOMETRICS AND FRUITS PRODUCTION OF Attalea nucifera (ARECACEAE) IN COLOMBIA FENOLOGÍA, PARÁMETROS BIOMÉTRICOS Y PRODUCTIVIDAD DE FRUTOS DE Attalea nucifera (ARECACEAE) EN COLOMBIA Ivón Jiménez-Morera1 , Néstor García1 1Departamento de Biología, Facultad de Ciencias, Pontificia Universidad Javeriana, Carrera 7 No. 40 – 62, Bogotá, Colombia *For correspondence: [email protected] Received: 06th February 2019, Returned for revision: 03rd May 2019, Accepted: 28th May 2019. Associate Editor: Xavier Marquínez-Casas. Citation/Citar este artículo como: Jiménez-Morera I, García N. Phenology, biometrics and fruits production of Attalea nucifera (Arecaceae) in Colombia. Acta biol. Colomb. 2020;25(1):104-111. DOI: http://dx.doi.org/10.15446/abc.v25n1.77701 ABSTRACT Attalea nucifera is a threatened palm endemic to the Magdalena River basin in Colombia. In the past its seeds were consumed by the inhabitants of the town of Guaduas, Cundinamarca, although currently its use is less frequent. To assess the productive potential of this palm, we studied its phenology, biometric parameters, and fruit productivity in a forest relict in Guaduas. Field work was carried out between April 2016 and March 2017. The reproductive cycle of this species lasted approximately 12 and a half months from bud to fruit ripening. Although bud production occurred throughout the year, it increased during periods of greatest rainfall. Flowering peaks occurred towards the end of the rainy season and fruits ripened towards the period of low rainfall. We found a positive correlation between the number of leaves in the crown and the production of reproductive structures (rs = 0.447, p = 0.004). Palms of A. nucifera produced on average 1.3 ripe infructescences per year (± 0.62 SD) with a mean of 22.4 (± 7.34 SD) fruits each. Fruit weighed 182.9 g (± 45.97 SD) on average, 5 % (9.3 g) of which corresponded to the edible nut. The reproductive cycle of A. nucifera is closely related to rainfall patterns and fruit production is low compared to other Attalea species. Keywords: Conservation, reproductive cycle, threatened species, Tropical Dry Forest. RESUMEN Attalea nucifera es una palma amenazada, endémica de la cuenca del río Magdalena, en Colombia. Aunque en el pasado sus frutos eran consumidos por los habitantes del municipio de Guaduas, Cundinamarca, en la actualidad su uso es esporádico. Para evaluar el potencial productivo de esta palma, se estudió su fenología, parámetros biométricos y productividad de frutos en un relicto de bosque del municipio de Guaduas. El trabajo de campo se realizó entre abril de 2016 y marzo de 2017. El ciclo reproductivo de esta especie tuvo una duración de 12 meses y medio desde la yema hasta la maduración de los frutos. Aunque durante todo el año hubo producción de yemas, estas se incrementaron durante los periodos de mayor precipitación. Los picos de floración se produjeron hacia el final del periodo de lluvias y la maduración de los frutos hacia el periodo de bajas precipitaciones. Se encontró una correlación positiva entre el número de hojas en la corona y la producción de estructuras reproductivas (rs = 0,447, p = 0,004). Las palmas de A. nucifera produjeron en promedio 1,3 infrutescencias maduras por año (± 0,62 DE) y cada una en promedio tuvo 22,4 (± 7,34 DE) frutos. Los frutos pesaron en promedio 182,9 g (± 45,97 DE), de los cuales el 5 % (9,3 g) correspondió a la nuez comestible. El ciclo reproductivo de A. nucifera está estrechamente relacionado con los patrones de precipitación y la producción de frutos es baja en comparación con otras especies de Attalea. Palabras clave: Bosque Seco Tropical, ciclo reproductivo, conservación, especie amenazada. 104 - Acta biol. Colomb., 25(1):104-111, Enero - Abril 2020 Reproductive phenology of Attalea nucifera INTRODUCTION Attalea nucifera H.Karst. is endemic to the Magdalena River Palms (family Arecaceae) are considered one of the most basin of Colombia and has been considered threatened due important plant groups for rural communities in the tropics. to the transformation and deterioration of its habitat -dry In Colombia, several species of palms are used to obtain to moderately wet riparian forests (Galeano and Bernal, oils, pulp, palm hearts, fibers, and construction materials, 2005; Galeano and Bernal, 2010). In the municipality of as well as other products (Galeano and Bernal, 2010). Palm Guaduas (Cundinamarca), its fruits have been consumed fruits are a source of food for many human communities for centuries. During the Royal Botanical Expedition (1783– (Mesa and Galeano, 2013; Ledezma-Rentería and Galeano, 1816), José Celestino Mutis described the use of these fruits 2014), and about 60 species of Colombian palms with for the extraction of oil, in addition to their use as food by the edible fruits have been recorded (Galeano and Bernal, rural population of Guaduas (Galeano, 1985). In 1856 2010; Mesa and Galeano, 2013; Ledezma-Rentería and the German botanist Hermann Karsten pointed out that the Galeano, 2014). Many of these fruits are rich in nutrients seeds tasted like almonds or walnuts, and farmers sold them and other bioactive molecules, and their consumption can as treats in the Guaduas market (Karsten, 1856). Over time, be beneficial to human health (Montúfaret al., 2010; Kang consumption of these nuts has decreased, but the species is et al., 2012; Li et al., 2016). still listed as a useful plant with promising potential (Pérez- Knowledge of phenological cycles and productivity is Arbeláez, 1994; Patiño, 2002). Today, the fruits are no longer important in designing effective management plans for fruit- marketed, and their consumption is sporadic (Prada, 2018). producing palms (Galeano et al., 2015). In tropical America, In order to assess the productive potential of A. nucifera, reproductive phenology and fruit productivity of a wide we studied its phenology, biometric parameters, and fruit variety of palm species have been studied. These include production in Guaduas, Cundinamarca. We asked the Mauritia flexuosaL.f. (Mendes et al., 2017), Acrocomia aculeata following research questions: What is the reproductive cycle (Jacq.) Lodd. ex Mart. (Scariot et al., 1995), Oenocarpus bataua of A. nucifera? What is the relationship of temperature and Mart. (Rojas-Robles and Stiles, 2009), Elaeis oleifera (Kunth) precipitation with the reproductive cycle? How much fruit do Cortés (Moreno and Romero, 2015), Attalea phalerata Mart. A. nucifera palms produce annually? And how are biometric ex Spreng. (Fava et al., 2011), Syagrus romanzoffiana (Cham.) parameters of individual palms related to productivity and Glassman (Mariano and Christianini, 2016), and Butia fruit biometrics? capitata (Mart.) Becc. (Silva and Scariot, 2013). Tropical palms exhibit annual or multi-year reproductive cycles (Rojas-Robles and Stiles, 2009), and their flowering tends to MATERIALS AND METHODS be synchronized with precipitation (Henderson et al., 2000; Fava et al., 2011; Mendes et al., 2017). Many palms maintain Study species a supply of fruits throughout the year, which represents a Attalea nucifera is a palm with a solitary, underground key resource for the frugivorous fauna (Adler and Lambert, stem (acaulescent). Adults have 7-14 leaves ca. 8 m long, 2008; Genini et al., 2009; Fava et al., 2011). with 92-122 leaflets per side, regularly arranged on the same The genus Attalea represents a group of palms plane, and apical leaflets are not fused. Staminate flowers characteristic of the warm lowlands in Colombia (Gaelano are arranged in two rows on the adaxial side of the rachillae and Bernal, 2010). The taxonomy of this group has been and can reach up to 2 cm long. Pistillate inflorescences controversial, with no consensus on the number of accepted have flowers arranged directly on the rachis, and fruits are species, which varies between 29 and 67 (Pintaud, 2008). In elliptical to almost spherical, 6 to 8 cm long (Galeano and Colombia, 16 species are recognized and are found in both Bernal, 2010). humid and dry forest habitats (Galeano and Bernal, 2010; Bernal et al., 2015). Attalea species have either pistillate, Study area staminate, or bisexual inflorescences (Dransfield et al., The studied population of A. nucifera occurs in a forest 2008). Individuals are monoecious, but because pistillate relict on the bank of Quebrada Cucharal (5°07’ N, and and staminate inflorescences seldom occur at the same 74°36’ W), in vereda Cucharal, municipality of Guaduas time, they are considered functionally dioecious (Moraes et (Cundinamarca). The area has an average elevation of 900 al., 1996; Núñez et al., 2005; Fava et al., 2011; Tucker et al., m above sea level, and corresponds to tropical dry forest 2018). Fruits are ellipsoid to ovoid, with one to several seeds, (Holdridge, 1987), with a vegetation matrix of pastures, tall the mesocarp is usually fleshy and fibrous, the endocarp is secondary vegetation, and gallery forest. During the period very hard, and seeds have a solid, homogeneous endosperm 2000-2017 average monthly temperature was 23.4 °C, and (Dransfield et al., 2008). Attalea fruits are rich in oils (Lleras average monthly rainfall was 105 mm. Between April 2016 and Coradin, 1988; Devia et al., 2002; Voeks, 2002), and and March 2017 monthly precipitation ranged from seven several species have been considered as promising oil sources mm to 233.9 mm, with an average of 99.6 mm (Fig. 1). (e.g., Markley, 1971; Devia et al., 2002; Bernal et al., 2010). The highest rainfall occurred between March and May, and Acta biol. Colomb., 25(1):104-111, Enero - Abril 2020 - 105 Ivón Jiménez-Morera, Néstor García the lowest rainfall levels were in February and June-August diameter, fresh weight of the whole fruit, of the shell, the (Fig. 1). The average monthly temperature fluctuated endocarp and the nut.