Badri Mounawer, Zitoun Adel, Ilahi Houcine, Huguet Thierry, Aouani Mohamed Elarbi
Laboratoire Interactions Légumineuses Microorganismes, Centre de Biotechnologie, Technopole de Borj-Cédria, B.P. 901, 2050 Hammam-Lif, Tunisia.
J Genet. 2008 Dec;87(3):241-55. doi: 10.1007/s12041-008-0038-y.
Genetic variability in 10 natural Tunisian populations of Medicago laciniata were analysed using 19 quantitative traits and 12 polymorphic microsatellite loci. A large degree of genetic variability within-populations and among-populations was detected for both quantitative characters and molecular markers. High genetic differentiation among populations for quantitative traits was seen, with Q(ST) = 0.47, and F(ST) = 0.47 for microsatellite markers. Several quantitative traits displayed no statistical difference in the levels of Q(ST) and F(ST). Further, significant correlations between quantitative traits and eco-geographical factors suggest that divergence in the traits among populations may track environmental differences. There was no significant correlation between genetic variability at quantitative traits and microsatellite markers within populations. The site-of-origin of eco-geographical factors explain between 18.13% and 23.40% of genetic variance among populations at quantitative traits and microsatellite markers, respectively. The environmental factors that most influence variation in measured traits among populations are assimilated phosphorus (P(2)0(5)) and mean annual rainfall, followed by climate and soil texture, altitude and organic matter. Significant associations between eco-geographical factors and gene diversity, He, were established in five microsatellite loci suggesting that these simple sequence repeats (SSRs) are not necessarily biologically neutral.
利用19个数量性状和12个多态性微卫星位点，对突尼斯10个自然苜蓿种群的遗传变异性进行了分析。在数量性状和分子标记方面，均检测到种群内和种群间存在很大程度的遗传变异性。数量性状的种群间遗传分化程度较高，Q(ST)=0.47，微卫星标记的F(ST)=0.47。几个数量性状在Q(ST)和F(ST)水平上没有统计学差异。此外，数量性状与生态地理因子之间的显著相关性表明，种群间性状的差异可能与环境差异有关。种群内数量性状的遗传变异性与微卫星标记之间没有显著相关性。生态地理因子的起源地分别解释了数量性状和微卫星标记在种群间遗传方差的18.13%和23.40%。对种群间测量性状变异影响最大的环境因子是有效磷（P₂O₅）和年平均降雨量，其次是气候、土壤质地、海拔和有机质。在5个微卫星位点上，生态地理因子与基因多样性He之间建立了显著关联，这表明这些简单序列重复（SSR）不一定是生物学中性的。
