Genetic and Genomic Approaches for Improving Yield Potential, Oil Content, and Climate Resilience in Sunflower (Helianthus Annuus L.)

Sunflower (Helianthus annuus L.) is one of the most important oilseed crops worldwide because of its high-quality edible oil, nutritional value and adaptability to diverse environmental conditions. However, increasing climatic variability, including drought, high temperature, soil salinity and irregular rainfall, poses serious challenges to sunflower productivity and oil quality. Conventional breeding has contributed considerably to the development of high-yielding hybrids, but the complex genetic inheritance of seed yield, oil accumulation and abiotic stress tolerance requires more advanced breeding strategies. Recent developments in molecular genetics and genomics, including quantitative trait locus (QTL) mapping, genome-wide association studies (GWAS), marker-assisted selection (MAS), genomic selection (GS), transcriptomics, gene expression analysis and CRISPR/Cas-based genome editing, provide new opportunities for improving sunflower cultivars. The reference genome of sunflower has facilitated the identification of important genomic regions associated with oil biosynthesis, flowering time and agronomic performance. Several studies have identified candidate genes involved in fatty acid metabolism, drought tolerance, salinity resistance and plant adaptation. In particular, the identification of FAD2 and other lipid-metabolism-related genes provides opportunities for improving oil composition and nutritional quality. Similarly, genomic studies have identified drought- and salinity-associated loci that can be incorporated into breeding programmes. This review examines the potential of genetic and genomic approaches for developing sunflower cultivars with improved seed yield, enhanced oil content, desirable fatty acid composition and greater climate resilience. An integrated approach combining conventional breeding, molecular markers, genomic selection, high-throughput phenotyping and multi-environment evaluation is recommended for developing stable, high-performing sunflower hybrids under changing climatic conditions.