Genetic variability of watermelon accessions based on microsatellite markers

Abstract

ABSTRACT. We analyzed the genetic variability of 40 watermelon accessions collected from 8 regions of Northeastern Brazil using microsatellite markers, in order to suggest strategies of conservation and utilization of genetic variability in this species. These accessions are not commercial cultivars. They were sampled in areas of traditional farmers that usually keep their own seeds for future plantings year after year. An UPGMA dendrogram was generated from a distance matrix of the Jaccard coefficient, based on 41 alleles of 13 microsatellite loci. Analysis of molecular variance was made by partitioning between and within geographical regions. The similarity coefficient between accessions ranged from 37 to 96%; the dendrogram gave a co-phenetic value of 0.80. The among population genetic variability was high ( populations, so regional species diversity will be better represented and preserved in the germplasm bank.

Assessment of the genetic diversity of dessert watermelon (Citrullus lanatus var. lanatus) landrace collections of South Africa using SSR markers

“…Zhao et al (2014) reported PIC values ranging from 0.04 to 0.67 with a mean of 0.39 lower than the current study. Minsart et al (2011) andde Gama et al (2013) also reported mean PIC values of 0.37 and 0.39, respectively also lower than the current study. The high levels of polymorphism observed in the current study could be due to large genome size, outcrossing nature and heterozygosity of watermelon.…”

“…The SSR markers generated a total of 94 putative alleles (Table 3). This was higher than 41 alleles detected by de Gama et al (2013) among dessert watermelon accessions. Sheng et al (2012) detected a total of 94 putative alleles, similar to the current study.…”

“…Results of the present study agree with Mujaju et al (2011) and Minsart et al (2011) who reported similar trends among and between watermelon accessions. de Gama et al (2013) also reported 68 and 32% variation within and among watermelon accessions respectively. The magnitudes of between and within population differentiation were quantified using the Fstatistics according to Wright (1951).…”