High-throughput single nucleotide polymorphism (SNP) arrays are important genotyping tools that accelerate breeding programs and basic research. In the cultivation wax gourd, a vital vegetable crop in China characterized by extensive cultivation and genetic resources, there has been an absence of a high-throughput genotyping platform. Concurrently, market demands for high-quality fresh consumption and processing-specific wax gourd varieties are becoming increasingly diversified. Confronted with the bottlenecks of long breeding cycles and low efficiency inherent in traditional breeding methods, there is a need for precise and efficient modern breeding tools to accelerate the development of new wax gourd cultivars possessing strong disease resistance, superior quality, and traits tailored to specific utilization requirements.
To that end, a team of researchers from China developed the first high-density 10K SNP array for wax gourd using genotyping by target sequencing (GBTS) technology. They reported their results in the Journal of Integrative Agriculture.
"To demonstrate its utility, genetic distances among 19 elite inbred lines were calculated from SNP data and correlated with heterosis for single fruit weight," shares corresponding author Baobin Mi, an associate professor at Hunan Academy of Agricultural Sciences. "The results revealed that greater genetic distance was associated with higher middle parent heterosis (MPH) for single fruit weight."
Furthermore, 56 commercial wax gourd cultivars collected from eight regions were selected and genotyped.
Population structure analysis, phylogenetic analysis, and principal component analysis (PCA) collectively indicated that these cultivars fall into two major groups. Group I, comprising black or dark green skinned wax gourds, exhibited lower genetic diversity than Group II, which includes green or light green skinned varieties, reflecting shorter genetic distances within Group I. Finally, 60 polymorphic SNPs were used to construct DNA fingerprints for distinguishing the 56 cultivars.
"As the first high-throughput genotyping platform for wax gourd, this SNP array provides an effective and powerful tool for genetic analysis." adds co-corresponding author Fangfang Wu, an associate professor at Hunan Agricultural University.
