Introgression of Gossypium barbadense L. into Upland cotton germplasm RMBUP-C4S1

Authors: Jenkins, Johnie; McCarty, Jack; Deng, Dewayne; GENG, LIGE - Hebei Academy Of Agriculture & Forestry; Hayes, Russell - Russ; JONES, DON - Cotton, Inc; MAMMADOVA, RUFA - Azerbaijan Academy Of Sciences

Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/14/2018
Publication Date: 6/22/2018
Citation: Jenkins, J.N., McCarty Jr, J.C., Deng, D.D., Geng, L., Hayes, R.W., Jones, D.C., Mammadova, R. 2018. Introgression of Gossypium barbadense L. into Upland cotton germplasm RMBUP-C4S1. Euphytica. 214:118. https://doi.org/10.1007/s10681-018-2200-9.
DOI: https://doi.org/10.1007/s10681-018-2200-9

Interpretive Summary: Cotton varieties commonly grown around the world are primarily what is called Upland cotton. These comprise most of the acreage worldwide. However, there is another type of cottons with longer and stronger fibers and these extra-long staple (ELS) varieties are grown on a very small acreage worldwide as they are not as widely adapted and do not yield as high as Upland cotton. Upland cotton and ELS cotton are different species. Crosses between the two species generally results in distorted segregation in later generations of the crosses and thus it is difficult to move genes for longer and stronger fiber from the ELS to Upland varieties. Many breeders have tried without much success to accomplish this. We took a different approach called chromosome substitution lines (CSL) where one chromosome at a time is substituted from ELS to Upland. A series of 18 CSL have been developed and we crossed these with three Upland varieties and developed a random mated population called RMBUP-C4S1. When we genotyped this population with 139 molecular markers to determine the amount of transfer from ELS to Upland. We found 121 of 139 marker alleles from ELS had been moved into the random mated population. We found a range of 10-28 ELS alleles in individual plants. We also found alleles from 6-14 chromosomes in individual plants. These data indicate that we have been successful in transferring many alleles from a ELS variety into our Upland population. Since we had considerable success in transferring ELS molecular marker alleles into our population, this should be a very good breeding population from which to develop varieties with longer and stronger fiber properties.

Technical Abstract: Gossypium barbadense L. cotton has significantly better fiber quality than Upland cotton (G. hirsutum L); however, yield and environmental adaptation of G. barbadense is not as wide as Upland. Most cotton in the world is planted to Upland cultivars. Many attempts have been made, over a considerable number of years, to introgress fiber quality alleles from G. barbadense into Upland. However, introgression barriers, primarily in the form of interspecific incompatibility, have limited these traditional approaches. The use of chromosome substitution lines (CSL) as a bridge should provide a more efficient way to introgress alleles from G. barbadense into Upland. We crossed 18 G. barbadense CSL to three cultivars and developed a random mated population. After five cycles of random mating followed by one generation of self- pollination to increase the seed supply, we grew the random mated population and used 139 G. barbadense chromosome specific SSR markers to assess a random sample of 96 plants for introgression. We recovered 121 of 139 marker loci among the 96 plants. The distribution of the G. barbadense alleles ranged from 10-28 alleles in each plant. Among the 96 plants we found individual plants with marker loci from 6 to 14 chromosomes or chromosome arms. Identity by descent showed little relatedness among plants and no population structure was indicated by a heat map. Using CSL we were able to develop a mostly Upland random mated population with considerable introgression of G. barbadense alleles which should be useful for breeding.