2013 Annual Report
1a.Objectives (from AD-416):
Develop carrot breeding stocks for production in organic agriculture systems with improved nutritional value, trial carrots in diverse growing locations, and release germplasm to the seed industry. Grow carrot trials to evaluate Nematode resistance in California.
1b.Approach (from AD-416):
a. Evaluate carrot genetic stocks for nematode resistance.
b. Provide selected carrots for further evaluation.
c. Assist in large-scale testing of resistance and outreach information development.
This project was renumbered from 3655-21000-048-46A to 3655-21000-062-20A. Two root-knot nematode resistance screening trials were conducted in California in 2012. The trials were at the University of California South Coast Research Center, Tustin, CA on separate field sites, one infested with M. incognita and one with M. javanica. In each trial, 13 carrot lines from the primary carrot germplasm set being compared for organic versus conventional production systems were screened together with a standard susceptible control variety. The trial was planted in June 2012 and evaluated in November 2012. Six lines were highly resistant to both nematode species, indicated by low root galling scores. Another four lines expressed moderate resistance to both nematodes, and the remaining three lines were highly susceptible with highly galled roots. Selected resistant plant taproots were shipped to Wisconsin for advancement and seed increase. Results of the field screenings in 2012 were presented in the California Fresh Carrot Advisory Board Annual report and at the California Carrot Industry symposium in March 2013. A field day was held in November 2012 at the Tustin field sites during the carrot line evaluations. The field day was attended by representatives of the major carrot processing companies and carrot breeders from the primary carrot seed production companies. The same lines evaluated in 2012 together with the remaining lines from the primary project set are being evaluated in a second year trial planted in May 2013 at the University of California Kearney Research Center, Parlier, California. The lines will be evaluated for nematode resistance in September 2013, at which time an industry field day will be held, and the results shared with the carrot industry through their annual report and carrot symposium. This research relates to Objective 1, Determine the genetic basis of and initiate selection for carrot, onion, cucumber, and melon quality attributes influencing human nutrition and health, disease resistances, and yield and quality components, and stress tolerance in cucurbits, and perform field performance and quality trials and Objective 2, Utilize current biotechnology to discover and evaluate genetic variation and to map agriculturally important traits in Allium, Cucurbit, and Daucus germplasm, and to develop genetic and breeding stocks, by evaluating nematode resistance in carrot stocks being developed.