Location: Crop Germplasm Research
Title: Non-destructive measurements of cottonseed nutritional trait diversity in the US National Cotton Germplasm Collection Authors
|Horn, Patrick -|
|Kothari, Neha -|
|Dever, Jane -|
|Chapman, Kent -|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 9, 2014
Publication Date: February 24, 2015
Citation: Hinze, L.L., Horn, P.J., Kothari, N., Dever, J.K., Frelichowski, J.E., Chapman, K.D., Percy, R.G. 2015. Non-destructive measurements of cottonseed nutritional trait diversity in the US National Cotton Germplasm Collection. Crop Science. 55:770-782. Interpretive Summary: Characterizing the genetic variation within the US National Cotton Germplasm Collection is essential to assuring that these resources can be utilized to give cotton the ability to adapt to new pests, new diseases, and new climatic conditions and to make improvements in yield, fiber, and seed traits. To effectively and efficiently use the genetic variation of the Collection, it is necessary to understand the extent, nature, and structure of the available genetic diversity. In an effort to analyze and characterize the genetic diversity available in the Collection, this research evaluated the diversity for three cottonseed traits in a subset of entries representing about 20% of the Collection and comprising entries from all nine genomes and 33 species levels as represented in the Collection. From this study we determined that there generally was a large amount of variation in the Collection for all cottonseed traits, and this variation exceeded that of current commercial cultivars. We demonstrated that most of the variation useful to improve oil and protein content can be found within commercial species and, therefore, these characteristics can easily be transferred from the underutilized material in the Collection into improved breeding material. Making available the results of these characterizations of the Collection allows breeders and geneticists to make more informed choices for research, education, and breeding efforts, ultimately contributing important traits to benefit farmers and consumers globally.
Technical Abstract: Recent studies have suggested that cottonseed (Gossypium spp.) has the potential to contribute to the effort against world hunger, particularly by providing a high quality protein source. This report analyzed the diversity in protein content and other seed quality factors in the US National Cotton Germplasm Collection. Nine genomes (one tetraploid and eight diploid) and 33 species (five tetraploid and 28 diploid) were surveyed in this examination of 2,256 accessions. A novel non-destructive NMR technique was applied to measure oil and protein content, seed indices were calculated, and this data was associated with molecular marker information. Oil content ranged from 8 to 27%, protein values ranged from 10 to 36%, and seed index was lowest at 1 gram per 100 seeds and extended up to 18 grams per 100 seeds. Most of the range in values for these traits resided within G. hirsutum and G. barbadense; thus implying that variability for cottonseed quality can be introduced with relative ease in current breeding programs. The diploid genomes generally had extremely low values for oil, protein, and seed index. Molecular marker information indicated that chromosome 21 was likely associated with oil content. Understanding how these seed quality factors vary independently and in relation to each other will allow us to better select parents for breeding programs, and identifying associations with molecular markers may help us enhance progress through marker-assisted selection approaches.