Molecular dissection of sugar related traits and it’s attributes in Saccharum spp. hybrids

Sugarcane is one of the most important crops in the tropical and sub-tropical regions worldwide because it supplies over half of the world’s sugar. The main goal of sugarcane breeding programs is releasing new cultivars with improved sugar content, disease resistance and agronomic traits. Molecular markers linked to the sugar yield would greatly facilitate the development of sugarcane cultivars with higher sugar content. In this study, quantitative trait loci (QTL) associated with sugar and yield related traits were identified using a segregating F1 population derived from two Saccharum spp. hybrids. Specifically, BRIX, POL, recoverable sugar content (SC), fiber content (FC), moisture content (MC), juice purity, stalk diameter (SD), and stalk weight (SW) data were collected from a replicated field trial of a bi-parental population. A total of 36 and nine QTL for sugar and yield related traits, respectively were identified using a high density genetic map with markers developed by genotyping-by-sequencing. Of the 45 detected QTL, seven QTL were associated with each of the three sugar related traits BRIX, POL, and SC; six QTL with FC and MC; three QTL with juice purity; four QTL with SD; and five QTL with SW. The QTL explained a total of phenotypic variations of 70.90, 61.80, 61.68, 68.67, 91.62, 33.00, 49.91, and 64.49% for BRIX, POL, SC, FC, MC, purity, SD, and SW, respectively. Upon validation, markers from the identified QTL would be useful in marker-assisted selection for selecting superior cultivars with these traits.