Mining of Simple Sequence Repeats Loci, Genetic Relationship And Population Structure of Bottle Gourd (Lagenaria Siceraria (Molina) Standl.) Accessions With Different Geographical Origin Using Single Nucleotide Polymorphism (SNPs) Markers

Abstract Lagenaria siceraria (Molina) Standl. (2n = 2x = 22) is an important horticultural and medicinal crop grown worldwide serving for food and pharmaceutical industries. The crop exhibit extensive phenotypic and genetic variation useful for cultivar obtention targeting economic traits, however limited genomic resources are available for effective germplasm characterization into breeding and conservation strategies. This study determined the genetic relationships and population structure in a collection of different accessions of bottle gourd prevenient from Chile, Asia, and South Africa by using single nucleotide polymorphism (SNPs) markers and mining of simple sequence repeats (SSR) loci derived from genotyping-by-sequencing (GBS) data. The GBS resulted in 12,766 SNPs molecular markers classified as moderate to highly informative with mean polymorphic information content of 0.29. The mean gene diversity of 0.16, indicated low genetic differentiation of the accessions. Analysis of molecular variance revealed lower differentiation between (36%) than within (48%) bottle gourd accessions suggesting that random mating system dominates inbreeding. Population structure revealed two genetically differentiated groups comprising of South Africa accessions and an admixed group with genotypes of Asian and Chilean origin. The results of SSR loci mining from GBS data should be developed and validated before being used in diverse bottle gourd accessions. The SNPs markers developed in the present study are useful genomic resources in bottle gourd breeding programs for assessing the extent of genetic diversity for effective parental selection and breeding.