Association mapping identifies quantitative trait loci (QTLs) by examining the marker-trait associations that can be attributed to the strength of linkage disequilibrium between markers and functional polymorphisms across a set of diverse germplasm. In this study, association mapping was performed to detect QTL-linked and genome wide SSR markers linked to phenolic compounds of extraction meal in a population of 49 genetically diverse oilseed rape cultivars of dark-seeded, wintertype oilseed rape accessions. Correction for population structure was performed using 559 genome wide SSR markers. Results showed that seed colour is an important contributor to seed meal quality. Totally, 52 SSR markers linked to phenolic compounds were detected, five of them being QTL linked markers. Some of these markers were already mapped on Brassica napus chromosomes that contain known QTL controlling oilseed rape meal quality traits. Our results demonstrate that association mapping is a useful approach to complement and enhance previous QTL information for marker-assisted selection.

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General and specific combining abilities of three cytoplasmic male sterile and four restorer lines of sunflower were studied in a randomized complete block design with three replications under normal irrigation and drought stress conditions in Eslamabad-e-Gharb, Iran during two growing season (2019 and 2020). Drought stress reduced seed yield, oil yield, thousand seeds weight and head diameter by 21.9%, 18.1%, 14.3% and 11.5%, respectively. Line × tester analysis indicated that the effect of lines was significant for the number of days to flowering, plant height, grain yield and seed oil percentage under both normal and drought stress conditions. The effect of lines was significant for number of days to maturity and number of seeds per head under normal condition and for thousand seeds weight under drought stress condition. Contribution of lines × testers were higher than the variances of lines or testers for of most of all the studied traits indicating the major role of non-additive effects on expression of theses traits. R131 was differentiated with the highest positive general combining ability for grain and oil yield in both normal and drought stress conditions. Among the testers, AGK32 and AF81-222 had the highest general combining ability for grain yield under normal and stressed conditions, respectively. R131×AGK38, with grain yields of 4414 and 3457 kg ha-1 under normal and drought stress conditions respectively, had the highest specific combining ability for grain and oil yield under both conditions. The results of this study showed that the genetic materials and environmental conditions can affect the nature of gene effect and combining ability of sunflower parent lines and crosses.