Location: Plant Stress and Germplasm Development Research
Project Number: 3096-21000-022-027-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Mar 30, 2020
End Date: May 31, 2022
Objective:
1. Evaluate around 500 cotton germplasm accessions from diverse geographical location of Uzbekistan or Asia-regions currently in the USDA-ARS Cotton Germplasm Collection, and chromosome substitution (CS) lines developed from the tetraploid species of G. barbadense, G. tomentosum and G. mustelinum in infested FOV4 fields in California.
2. Identify and further evaluate previously developed and identified tolerant FOV4 cotton progeny, breeding lines, and populations to validate the level of FOV4 resistance/tolerance for possible public germplasm release.
Approach:
Fusarium wilt disease caused by Fusarium oxysporum f. sp. vasinfectum (FOV) causes significant economic losses to cotton farmers of the USA, Uzbekistan and many other countries. Host-plant resistance is the only cost-effective long-term solution to address the problem of FOV, but its use is seriously impeded by the narrow genetic base of Upland cotton. The proposed project will evaluate germplasm accessions from the USDA-ARS Cotton Germplasm Collection, and chromosome substitution (CS) lines developed from the tetraploid species of G. barbadense, G. tomentosum and G. mustelinum in infested FOV race 4 (FOV4) fields in California. In addition, progeny, breeding lines and populations previously developed will be evaluated to validate the level of FOV4 resistance/tolerance for possible public germplasm release. Diverse breeding methodologies have been used to develop and select breeding lines and germplasm resistant to FOV4. Additional entries of interest identified from ongoing screening and selection efforts at the USDA-ARS, SPA, Cropping Systems Research Laboratory, Lubbock, TX and/or other germplasm sources will be evaluated as appropriate for FOV4 resistance. Responses of FOV4 infection and host-plant resistance from field test-evaluations will be examined using ANOVA or nonparametric analyses. Field experiments will typically use a randomized complete block or incomplete block design with a minimum of 3 replications, unless seed availability from selections is limited. Measured responses to FOV include percent plant survival and disease severity index standardized ratings (root vascular and foliar). Selected FOV resistant material will be subjected to broader testing such as yield and lint turnout using 25- or 50-boll samples, or 6-pound samples of seed cotton, depending on the amount of seed available and associated stage of progeny development; and fiber quality measurements such as fiber length, strength, and micronaire using HVI analyses. This research will also support existing projects to identify and validate biomarkers, which will be used to incorporate genes conferring FOV resistance into elite cultivars by marker-assisted selection. Through this agreement USDA-ARS will support collaborative efforts with the University of California and provide support for a Staff Research Associated or similar research staff who will be located at the Shafter Research Station, Shafter, CA to help with the ongoing genetic/breeding effort and evaluations of progeny, breeding lines and germplasm development for FOV race 4 resistance.
