LAUSR

Abstract Citron watermelon genetic resources are useful for dessert watermelon breeding. The objective of the present study was to assess the genetic diversity present among citron watermelon landrace collections of South Africa using simple sequence repeat (SSR) markers. Thirty four diverse citron watermelon landraces were genotyped using 10 SSR markers. The markers amplified a total of 72 alleles from the sampled populations. Number of alleles ranged from 2 to 17 with a mean of 7.2 per locus. Number of effective alleles ranged from 1.03 to 6.74 with a mean of 3.54. The mean observed and expected heterozygosity were 0.48 and 0.60, respectively. The mean inbreeding coefficient was 0.18 suggesting high levels of heterozygosity among the collections. The mean polymorphic information content (PIC) of the SSR loci was 0.60 suggesting their value in genetic diversity analysis of watermelon. Analysis of molecular variance revealed highly significant difference ( P