Lanes Éder C M, Motoike Sérgio Y, Kuki Kacilda N, Resende Marcos D V, Caixeta Eveline T
From the Laboratory of Biotechnology and Plant Breeding, Department of Plant Science, Federal University of Viçosa, 36570-000 Viçosa, MG, Brazil (Lanes, Motoike, and Kuki); Department of Forest Engineering, Embrapa Forestry/Federal University of Viçosa, 36570-000 Viçosa, MG, Brazil (Resende); and Institute of Biotechnology Applied to Agriculture (BIOAGRO), Embrapa Coffee/Federal University of Viçosa, BioCafé, 36570-000 Viçosa, MG, Brazil (Caixeta).
J Hered. 2016 Nov;107(6):527-36. doi: 10.1093/jhered/esw038. Epub 2016 Jun 9.
Acrocomia aculeata (Arecaceae), a palm endemic to South and Central America, is a potential oil crop. Knowledge of the mating system of this species is limited to its reproductive biology and to studies using molecular markers. The present study analyzed genetic diversity between its developmental stages and determined its prevailing mating system in order to support genetic conservation and breeding programs. We tested 9 microsatellite markers in 27 mother trees (adult plants) and 157 offspring (juvenile plants) from the southeastern region of Brazil. Heterozygosity levels differed between the 2 studied life stages, as indicated by the fixation index of adult and juvenile trees, suggesting that selection against homozygotes occurs during the plant life cycle. The mating system parameters analyzed indicate that A. aculeata is predominantly outcrossing (allogamous). However, its low levels of selfing suggest that there is individual variation with regard to self-incompatibility, which can be a survival strategy in isolated or fragmented habitats. Deviations in variance effective size were detected because of high mating rates among relatives and correlated matings. These findings indicate that the main source of inbreeding results from biparental inbreeding in the population and that the progenies are predominantly composed of full-sibs. The information provided by this study on the ecology and reproduction dynamics of A. aculeata should be useful to both breeding and genetic conservation programs, allowing the development of more precise mathematical models and the estimation of the appropriate number of mother trees for seed collection.
刺葵（棕榈科）是一种原产于南美洲和中美洲的棕榈树，是一种潜在的油料作物。关于该物种交配系统的知识仅限于其生殖生物学以及使用分子标记的研究。本研究分析了其发育阶段之间的遗传多样性，并确定了其主要的交配系统，以支持遗传保护和育种计划。我们在来自巴西东南部地区的27棵母树（成年植株）和157株后代（幼年植株）中测试了9个微卫星标记。成年树和幼年树的固定指数表明，两个研究的生命阶段之间的杂合度水平存在差异，这表明在植物生命周期中存在对纯合子的选择。所分析的交配系统参数表明，刺葵主要是异交（异花授粉）。然而，其较低的自交水平表明，在自交不亲和方面存在个体差异，这可能是在孤立或碎片化生境中的一种生存策略。由于亲属间的高交配率和相关交配，检测到方差有效大小的偏差。这些发现表明，近亲繁殖的主要来源是种群中的双亲近亲繁殖，并且后代主要由全同胞组成。本研究提供的关于刺葵生态和繁殖动态的信息，对育种和遗传保护计划都应是有用的，有助于开发更精确的数学模型，并估计种子采集所需的母树的适当数量。
