Screening of Chromosomal Substitution Cotton Lines through Simple Sequence Repeats Markers Relevant to Seed Traits for Protein and Oil Contents

Cotton (Gossypium spp.) is regarded as the world’s third important oilseed crop with abundant source of protein. However, development of genomic resources related to oil and protein traits are limited for this important crop. Chromosomal substitution lines with most of the background of G. hirsutum (Upland cotton) and foreground (a chromosome or segment) of Pima cotton (G. barbadense) have been released. Along with parents TM-1 (G. hirsutum) and 3-79 (G. barbadense), we have 17 CS-B lines, i.e., CS-B01, CS-B02, CS-B04, CS-B05 sh, CS-B06, CS-B07, CS-B11 sh, CS-B12 sh, CS-B14 sh, CS-B15 sh, CS-B16, CS-B17, CS-B18, CS-B22 sh, CS-B22 lo, 25 and CS-B26 lo. Simple sequence repeats (SSR) markers are widely used to study genetic structure of plant population. Our objective is to identify cotton lines, which harbor the quantitative traits loci (QTLs) associated to seed oil and protein traits. Sixteen SSR primers covering different QTL positions, which have been reported to govern oil and protein seed traits, were used for this study. Among these 16 QTLs, 10 have been associated with high oil content and other six have been reported for better protein profiles in cottonseed. On the basis of amplifications via polymerase chain reaction with these SSR primers, three of the progeny CS-B lines have been identified for genetic expression analyses pertaining to oil and protein traits in seeds.