|Hutmacher, Robert - University Of California|
|Wright, Steven - University Of California - Cooperative Extension Service|
Submitted to: Germplasm Release
Publication Type: Germplasm Registration
Publication Acceptance Date: 8/1/2015
Publication Date: 11/9/2015
Citation: Ulloa, M., Hutmacher, R., Percy, R.G., Wright, S., Burke, J.J. 2015. Release of Pima SJ-FR05, Pima SJ-FR06, Pima SJ-FR07, Pima SJ-FR08, and Pima SJ-FR09 Pima cotton with improved FOV4 resistance, and good lint yield and fiber quality. Germplasm Release. p. 2.
Technical Abstract: Cotton breeders continue to need alternative sources of germplasm for improving Fusarium wilt [(Fusarium oxysporum f. sp. vasinfectum (FOV)], FOV race 4, resistance in Pima (Gossypium barbadense L.) cotton in California. For this purpose, the Agricultural Research Service, United States Department of Agriculture and University of California announce the release of five Pima cotton germplasm lines, Pima SJ-FR05, Pima SJ-FR06, Pima SJ-FR07, Pima SJ-FR08, and Pima SJ-FR09, that possess good resistance to FOV race 4, and good lint yield and fiber quality characteristics such as fiber fineness, length, and strength. Pima SJ-FR05-FR09 series originated from the cross of germplasm lines, Pima S-6 and 89590. Pima-S6 was released in 1983 as an F4 selection from a cross of two experimental lines (5934-23-2-6 and 5903-98-4-4). At the time of release, the major advantages of S-6 were early maturity and high yield. We now know that Pima S-6 also possesses a major gene(s) for FOV race 4 resistance. Line 89590 was developed from a cross between P62 and Sea Island St. Vincent. The cultivar Sea Island St. Vincent is an obsolete, low yield, and heat sensitive cultivar that possesses an exceptionally long and fine fiber. In multiple replicated infested FOV race 4 field and greenhouse tests, the SJ-FR05-FR09 lines showed good levels of resistance to FOV race 4, compared to the resistant and susceptible checks, and parental lines, but users should apply caution in utilizing these lines and should not assume that the lines provide complete resistance against FOV race 4. In addition, yield and fiber replicated trials revealed that the average values of fiber lengths and strengths of the Pima SJ-FR05-FR09 series were good or not significantly different when compared to the San Joaquin Valley (SJV) Pima cotton standard of California. The lines performed overall really well, having similar or superior lint and gin turnout percentage, and lint yield average rate shows when compared to the SJV Pima cotton standard. The SJ-FR05-FR09 series will help to speed efforts to broaden the genetic base, which is critical to the success and future of the Pima cotton industry.