QTL Mapping Using Advanced Mapping Populations and High‐throughput Genotyping

Understanding the genetic basis of quantitative traits has been a major goal for plant breeders to use in breeding programs. However, the mapping of quantitative traits is time consuming and costly process. The advancements in molecular genetics and genomics have facilitated the dissection of quantitative trait loci (QTLs) underlying complex traits. Generally, bi-parental populations derived from only two parents are routinely used for QTL mapping. But in bi-parental populations, genetic recombination is limited and only two alleles are analyzed which limits the resolution for QTL detection. Recently, a multiparental population strategy has been used to interrogate multiple alleles and to provide an increased level of recombination and mapping resolution of QTLs. QTL mapping is often hindered by the expense and time required to screen the thousands of individuals of a segregating mapping population with several polymorphic markers. The genotyping with less number markers results in poor mapping resolution of QTLs. With the rapid development of next-generation sequencing-based high-throughput genotyping approaches, the resolution of QTLs has been improved significantly by increasing the number of markers. However, an efficient and advanced statistical method is required for QTL mapping of advanced mapping populations derived from the multiparental populations using high-throughput genotyping approaches.