Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 17, 2003
Publication Date: May 20, 2004
Citation: Levi, A., Thomas, C.E., Newman, M.L., Zhang, X. 2004. Preferential segregation of linkage-groups produced quasi-linkage in F2 mapping population of watermelon. [abstract]. Plant and Animal Genome XII Proceedings. p.755. Technical Abstract: A comparative linkage map for watermelon is being constructed using three mapping populations. They include a BC1 population [(Citrullus lanatus var. citroides PI 296341x C. lanatus var. lanatus cultivar New Hampshire Midget (NHM)] x NHM, a testcross population (TC) (C. lanatus var. citroides germplasm line Griffin 14113 x NHM) x C. colocynthis PI 386015, and an F2 population (PI 296341 x NHM). Common markers are being used to merge linkage groups from the three maps, and confirmed consistent distances among markers in linkage groups. In contrast with the BC1 and the TC populations, the F2 population displayed nonrandom assortment against several linkage groups. Major linkage groups that are distinct in the BC1 and TC populations could be readily merged using common markers. However, in the F2 population nonhomologous linkage groups merged into one large linkage group producing Quasi-Linkage. This anomaly may be a result of strong affinity between nonhomologous chromosomes, and may exist in F2 populations derived from wide crosses between certain cultivars of watermelon (Citrullus lanatus var. lanatus) and wild plant introductions (PIs) of C. lanatus var. citroides.