Genetic diversity among bitter palm populations in the state of Goiás

ABSTRACT Bitter palm is a palm tree species that produces bitter core, which is too appreciated in cooking and can be used in animal feeding, as well as in landscaping, but it is still little studied, which hinders strategies for its cultivation and breeding. The present work aimed at evaluating the genetic divergence among bitter palm populations of three municipalities of Goiás and quantifying the relative contribution of eight characteristics in the diversity, using multivariate procedures. Twenty-four individuals from three populations were analyzed, with individuals from three plants with 30 and 36 months of age. The characteristics evaluated were: stipe diameter, number of definitive leaves, plant height, length of first green leaf, number of leaf sheaths, length and weight of heart of palm, and diameter of heart of palm base. The genetic diversity of the populations was evaluated by Tocher’s grouping method based on the dissimilarity matrix obtained by standardized mean Euclidean distance and the principal component analysis with graphical dispersion in the Cartesian plane. The results demonstrated the existence of genetic variability and heritability estimates of high magnitude for plant height, leaf length, stalk diameter at 10 cm soil, number of heart of palm sheaths, and core diameter of heart of palm. The performance of the grouping by Tocher’s method based on the dissimilarity matrix promoted the formation of eight groups, evidencing the influence of the geographical origin in the grouping and the selection in non-destructive characters of high genetic correlation as stalk diameter and leaf length can promote important gains in the production of heart of palm.

摘要 苦芯棕榈（Bitter palm）是一类可产出苦芯的棕榈树种，其在烹饪领域广受赞誉，既可用于动物饲料制备，亦可应用于景观造景，但当前对该物种的研究仍较为匮乏，这阻碍了其栽培与育种相关策略的推进。本研究旨在通过多元分析方法，评估巴西戈亚斯州（Goiás）三个市镇的苦芯棕榈种群间的遗传分化，并量化8个性状对遗传多样性的相对贡献。本研究共分析了3个种群的24株个体，涵盖树龄为30个月和36个月的植株。本次评估的性状包括：茎秆直径、成熟叶片数量、植株高度、首片绿叶长度、叶鞘数量、棕榈芯（heart of palm）长度与重量，以及棕榈芯基部直径。种群遗传多样性分析采用基于标准化平均欧氏距离（standardized mean Euclidean distance）得到的不相似性矩阵（dissimilarity matrix）开展的Tocher聚类法（Tocher’s grouping method），以及基于笛卡尔平面（Cartesian plane）图形散点分布的主成分分析（principal component analysis）。结果表明，供试种群间存在遗传变异，且植株高度、叶片长度、10cm土层处茎秆直径、棕榈芯叶鞘数量以及棕榈芯直径的遗传力（heritability）估计值均处于较高水平。基于不相似性矩阵的Tocher聚类法将供试材料划分为8个类群，证实了地理起源对聚类结果的影响；选取茎秆直径、叶片长度等与遗传相关性较高的非破坏性性状开展选择，可有效提升棕榈芯的产量。