Physical and chemical variability of Camu-camu fruits in cultivated and uncultivated areas of the Colombian Amazon

Abstract Camu-camu (Myrciaria dubia, Myrtaceae) has the highest reported vitamin C concentrations of any native Amazonian fruit tree species, with increasing demand in domestic and international markets. With the goal of aiding management and conservation programs, we studied the diversity of camu-camu in cultivated and uncultivated areas, based on physicochemical characterization of the fruits. We evaluated 2,250 fruits from 87 plants from six localities of the Tarapacá district (Amazonas, Colombia) and from the Amazonian fruit germplasm bank of Agrosavia (Meta, Colombia). We found high physicochemical variability within and among localities, and superior fruits in the localities where non-cultivated plants were sampled, especially Pechiboy. Using correlations and principal component analyses, we identified the variables Brix value, ascorbic acid content, fruit weight and pulp yield as the most useful for intraspecific selection of plants. The most promising plants presented Brix values of 8.2 ± 0.88 (maximum 10.9), fruit mass of 14.4 ± 1.2 g (max. 18.4 g) and pulp yields of 0.82 ± 0.02 (max. 0.87). These plants can be considered as possible sources for future breeding work. We conclude that there are plants in Tarapacá with relevant characteristics for commercialization and improvement of the species.

摘要：卡姆果（Camu-camu，学名Myrciaria dubia，隶属桃金娘科Myrtaceae）是目前已报道的亚马逊原生果树中维生素C含量最高的物种，其国内外市场需求持续增长。为辅助该物种的管理与保护工作，本研究基于果实的理化特性分析，对栽培与非栽培生境中的卡姆果多样性展开探究。我们采集并评估了来自哥伦比亚亚马孙省塔拉帕卡区6个样点的87株植株的2250份果实，以及来自哥伦比亚梅塔省阿格罗萨维亚（Agrosavia）亚马逊果树种质资源库的种质材料。研究结果显示，各样点内部及样点间均存在较高的理化性状变异，且非栽培植株所在样点的果实品质更优异，尤以佩奇博伊（Pechiboy）样点为甚。通过相关性分析与主成分分析，我们筛选出白利糖度（Brix value）、抗坏血酸（ascorbic acid）含量、单果质量与出浆率这4项最适用于该物种种内植株选育的核心指标。表现最优的植株其白利糖度为8.2±0.88（最高可达10.9），单果质量为14.4±1.2 g（最大值18.4 g），出浆率为0.82±0.02（最大值0.87）。此类植株可作为未来育种工作的潜在种质资源。本研究最终得出结论：塔拉帕卡区存在具备商业化开发价值与品种改良潜力的优异植株。