title: Genetic diversity and population structure of wild/weedy eggplant (Solanum insanum, Solanaceae) in southern India: implications for conservation.
abstract: •
  
  
  OBJECTIVE
  Crop wild relatives represent important genetic resources for crop improvement and the preservation of native biodiversity. Eggplant (Solanum melongena), known as brinjal in India, ranks high among crops whose wild gene pools are underrepresented in ex situ collections and warrant urgent conservation. Knowledge of outcrossing rates and patterns of genetic variation among wild populations can aid in designing strategies for both in situ and ex situ preservation.•
  
  
  METHODS
  We used 14 microsatellite (simple sequence repeat) markers to examine genetic diversity, population structure, and outcrossing in 10 natural populations of wild/weedy eggplant (S. insanum = S. melongena var. insanum) and three cultivated populations in southern India.•
  
  
  RESULTS
  Multilocus FST analyses revealed strong differentiation among populations and significant isolation by distance. Bayesian model-based clustering, principal coordinate analysis, and hierarchical cluster analysis grouped the wild/weedy populations into three major clusters, largely according to their geographic origin. The three crop populations were similar to each other and grouped with two wild/weedy populations that occurred nearby. Outcrossing rates among the wild/weedy populations ranged from 5-33%, indicating a variable mixed-mating system.•
  
  
  CONCLUSIONS
  Geographic isolation has played a significant role in shaping the contemporary patterns of genetic differentiation among these populations, many of which represent excellent candidates for in situ conservation. In two cases, close genetic affinity between cultivars and nearby wild/weedy populations suggests that gene flow has occurred between them. To our knowledge, this is the first study investigating population-level patterns of genetic diversity in wild relatives of eggplant.
authors.affiliation: Department of Evolution, Ecology, and Organismal Biology, Ohio State University, 318 W. 12 St., Columbus, Ohio 43210 USA.
authors.forename: Evans
authors.initials: E
authors.lastname: Mutegi
authors.affiliation: Department of Evolution, Ecology, and Organismal Biology, Ohio State University, 318 W. 12 St., Columbus, Ohio 43210 USA.
authors.forename: Allison A
authors.initials: AA
authors.lastname: Snow
authors.affiliation: Department of Ecology and Environmental Sciences, Pondicherry University, Kalapet, Pondicherry 605014, India.
authors.forename: Muthu
authors.initials: M
authors.lastname: Rajkumar
authors.affiliation: IRD, UR 072, LEGS 91198 Gif-sur-yvette, France; Université Paris-Sud 11 91400 Orsay, France.
authors.forename: Remy
authors.initials: R
authors.lastname: Pasquet
authors.affiliation: Department of Ecology and Environmental Sciences, Pondicherry University, Kalapet, Pondicherry 605014, India.
authors.forename: Hopeland
authors.initials: H
authors.lastname: Ponniah
authors.affiliation: INRA, Unité de Génétique & Amélioration des Fruits et Légumes, UR1052, Domaine St Maurice, CS 60094 F-84143 Montfavet cedex, France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Daunay
authors.affiliation: Department of Ecology and Environmental Sciences, Pondicherry University, Kalapet, Pondicherry 605014, India.
authors.forename: Priya
authors.initials: P
authors.lastname: Davidar
mesh_terms: D003247:Conservation of Natural Resources; D014644:Genetic Variation; D006824:Hybridization, Genetic; D007194:India; D018895:Microsatellite Repeats; D032323:Solanum melongena / Q000235:genetics*
keywords: India; Solanaceae; Solanum insanum; Solanum melongena; brinjal; eggplant; genetic diversity; microsatellite; outcrossing rates; population structure; wild/weedy relatives