ARS | Publication request: Genetic Diversity of A-Genome Cotton.

Submitted to: Arkansas Agricultural Experiment Station Research Series
Publication Type: Experiment Station
Publication Acceptance Date: June 15, 2007
Publication Date: October 10, 2007
Citation: Kantartzi, S., Ulloa, M., Stewart, J. McD. 2007. Genetic Diversity of A-Genome Cotton. In: D.M. Oosterhuis (Ed.). Summaries of Arkansas Cotton Research 2006. Ark. Agri. Exp. Sta. Research Series 552. pp. 112-116.

Technical Abstract: Since Upland cotton (Gossypium hirsutum L.) is known to have relatively low levels of genetic diversity or variation in genetic makeup among individuals, a better understanding of this variation and relationships among possible sources of novel genes would be valuable. Therefore, analysis of genetic variation of the genus Gossypium, especially the diploids, could provide important information about the feasibility of using these genetic resources for cotton improvement. The A-genome cotton species, G. arboreum and G. herbaceum, are two of the closest living relatives of the cultivated tetraploids and, as such, can serve as a source of genetic diversity for cultivated tetraploid cottons. One of the important advancements in DNA technology is the ability to use molecular markers as a tool for crop improvement. A molecular marker is a small piece of DNA that can be detected chemically. Based on molecular marker (microsatellites) data, genetic distance values among G. herbaceum accessions ranged from 0.11 to 0.50 whereas the values for G. arboreum ranged from 0.19 to 0.48, showing that intra-specific genetic variability in the two species is similar. The Neighbor Joining dendrograms generated from genetic dissimilarity coefficients classified accessions within each species into distinct sub-clusters. A systematic genetic assessment of the gene resources will help to decrease the redundancy and to construct a core germplasm collection that is important for efficient use of these gene resources in cotton breeding.