Selection of SSR markers for identifying embryonic origin in three polyembryonic mango rootstock varieties
Alessandro Rosa Nascimento, Vespasiano Borges de Paiva Neto, Antonio Elton da Silva Costa, Kecia Mayara Galvão Araújo, Jerônimo Constantino Borel and Francine Hiromi Ishikawa
Abstract: Polyembryonic mango varieties, often used as rootstocks, produce two or more embryos per seed, one of which is genetically distinct from the mother plant. This study aimed to differentiate three mango varieties regarding embryonic origin, vigor, and genetic non-uniformity using SSR markers. The mango varieties evaluated were Espada, Capucho, and Coquinho, which are commonly used as rootstocks. Thirty primers reported in the literature were tested, along with variables such as emergence percentage, seedling number, and extent of polyembryony. Only primers MillHR26, MillHR36, MillHR32, and MillHR28 were polymorphic. No direct association was found between seedling vigor and embryonic origin. Zygotic embryos may have been suppressed in the Capucho variety, which also exhibited a greater extent of polyembryony. This probable suppression, combined with higher polyembryony, indicates Capucho as the most sui rootstock source for achieving genetic uniformity.