Location: Crop Germplasm ResearchTitle: The U.S. National Cotton Germplasm Collection – its Contents, Preservation, Characterization, and Evaluation Author
|Frelichowski, James - Jim|
|Campbell, Benjamin - Todd|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 2/18/2014
Publication Date: 7/2/2014
Citation: Percy, R.G., Frelichowski, J.E., Arnold, M., Campbell, B.T., Dever, J., Fang, D.D., Hinze, L.L., Main, D., Scheffler, J.A., Sheehan, M., Ulloa, M., Yu, J., Yu, J. 2014. The U.S. National Cotton Germplasm Collection – its Contents, Preservation, Characterization, and Evaluation. In: Abdurakhmonov, I. Editor. World Cotton Germplasm Resources. Rijeka, Croatia: InTech. 167-201. Available: http://www.intechopen.com/books/world-cotton-germplasm-resources/the-u-s-national-cotton-germplasm-collection-its-contents-preservation-characterization-and-evaluation. Interpretive Summary: The U.S. National Cotton Germplasm Collection is a vital resource to researchers and investigators working on the genetic improvement of cotton. However, the utility of the collection is directly related to a thorough description of its contents and public knowledge of the collection. A book chapter has been written describing content of the collection, how the collection has been developed and maintained, efforts to describe and characterize the collection, and evaluation efforts to identify useful traits for cotton improvement within the collection. Access to collection is free. Description of the collection in the book chapter promotes public and private use of its contents for the improvement of an important national crop.
Technical Abstract: The U.S. National Cotton Germplasm Collection (NCGC) currently has approximately 10,000 accessions covering 45 species of Gossypium. The collection is subdivided to seven different sub-collections that consist of: 1) a variety sub-collection, primarily G. hirsutum (prefixed by SA-), 2) a landrace sub-collection, primarily G. hirsutum (prefixed by TX-), 3) a G. barbadense sub-collection, (prefixed by GB-), 4) an Asiatic (A-genome species) sub-collection, (prefixed by either A1- or A2- for G. herbaceum or G. arboreum respectively), 5) a wild species sub-collection (prefixed by a taxon specific genome letter-number combination ), 6) a genetic marker sub-collection, and 7) a base sub-collection (i.e. NCGRP) of all materials in sub-collections1-6 and new plant introductions. The U.S. collection was initially built primarily through collecting trips to native locales, but in recent times it has come to rely more on germplasm exchange with other national germplasm collections. Since 1985 twelve acquisition trips have been made to collect germplasm, of which ten trips were in situ explorations, while two trips were conducted to exchange germplasm with India, China, Russia, and Uzbekistan. Phenotyping of the collection germplasm has served the dual purposes of describing the diversity within the collection and aiding in the identification of germplasm of interest to genetic improvement efforts. In recent years, the use of molecular markers has greatly improved the ability to assess and describe the diversity of the collection. Although numerous genomic studies have been conducted using materials of the collection, only recently was a systematic effort been made to characterize the collection using 105 molecular markers on over 2,000 accessions, or approximately a fifth of the collection. Currently, numerous efforts at evaluating the collection are ongoing and concern such subjects as heat tolerance, drought tolerance, resistance to the thrips, and resistance to Cotton Leaf Curl Virus, among many. The collection has a policy of free and equal access to its contents, and distributions are limited only by the availability of the germplasm at the time of the request and by proper adherence to customs and phytosanitary laws of the U.S. and the country of the requesting individual.