Validated markers for sunflower (Helianthus annuus L.) breeding

Authors: RAUF, SAEED - University Of Sargodha; Warburton, Marilyn; NAEEM, AMNA - University Of Sargodha; KAINAT, WARDAH - University Of Sargodha

Submitted to: OCL - Oilseeds & fats, Crops and Lipids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/13/2020
Publication Date: 9/23/2020
Citation: Rauf, S., Warburton, M.L., Naeem, A., Kainat, W. 2020. Validated markers for sunflower (Helianthus annuus L.) breeding. OCL - Oilseeds & fats, Crops and Lipids. 27. Article 47. https://doi.org/10.1051/ocl/2020042.
DOI: https://doi.org/10.1051/ocl/2020042

Interpretive Summary: Sunflowers are economically important to US farmers, as they are used for oil production, confectionary and roasting seeds, and birdseed. Sunflower breeding can be made more efficient by the use of molecular marker assisted breeding, but historically, there have been few markers that could be used. This is beginning to change, and this review presents the latest results for markers ready for breeders, for many traits, all in one convenient resource.

Technical Abstract: Sunflower is native to north America and is grown for edible oil, seed roasting, confectionary products and bird food worldwide. Plant breeders and biotechnologists characterize and utilize genetic diversity in cultivated and wild germplasm to achieve various breeding objectives. Molecular markers have been developed to facilitate the sunflower breeding. In this regard, markers identified as linked to monogenic traits in various populations may be used to select plants with desired traits. Quantitative Trait Loci (QTL) mapping of many economically important traits has also been done, and markers linked to QTLs dispersed throughout the sunflower genome in specific population and target environment have been identified. However, it is important to validate all identified linked markers in various genetic backgrounds and environments to ensure widespread utility. Therefore, this review was undertaken to discuss molecular markers which have been validated in different genetic backgrounds for traits of economic interest in sunflower. Review of the literature identified validated markers available for several monogenic traits including the related to resistance against pathogens such as Puccinia heliathii, Plasmopara helstedii and the parasitic plant Orobanche. Scleortinia stalk resistance is a polygenic trait and the only one for which developed markers were reported that were validated in populations independent of the original mapping population. Publicly available inbred lines carrying multiple resistant genes have been developed via marker assisted selection. Validated markers related to economical traits such as high oleic acid and fertility restoration are also available. Molecular markers for difficult and expensive traits such as total fatty acids, vitamins and sterols may greatly facilitate the modification of sunflower oil and could be highly useful for development of various types of oil to fulfill industrial and consumer demands. This review highlights a lack of concrete effort to develop, validate, and publicize markers for many economically important traits in sunflower. This may partly be due to lack of funding available in developing countries despite the importance of this hybrid crop. The International Sunflower consortium has made 3.6 GB of genomic data available in 2017. This resource must now be exploited to develop new SNP based markers linked to genes of interest. Recent studies have shown that these markers may able to mine allelic diversity related to economically important traits, especially those also well studied in other organisms, such as seed oil content and resistance genes.