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Characterization and Performance of 16 New Inbred Lines of Lettuce

Ivan Simko, Ryan J. Hayes, Carolee T. Bull, Beiquan Mou, Yaguang Luo, Mark A. Trent, Amy J. Atallah, Edward J. Ryder, Rebecca G. Sideman
Hortscience 2014 v.49 no.5 pp. 679-687
Agricultural Research Service, Lactuca sativa, Verticillium wilt, bacterial diseases of plants, breeding lines, dieback, disease resistance, downy mildew, germplasm releases, inbred lines, leaf lettuce, leaf spot, leaves, plant breeding, salads, United States
The Agricultural Research Service, U.S. Department of Agriculture announces the release of sixteen breeding lines of lettuce (Lactuca sativa L.). Five (SM13-I1, SM13-I2, SM13-I3, SM13-I4, and SM13-I5) of the six iceberg breeding lines can be used for whole head or salad blend production; the sixth iceberg line (RH08-0111) does not form heads that meet the modern iceberg standard. This breeding line, however, can be used in breeding programs because it combines high level resistances to downy mildew, bacterial leaf spot, Verticillium wilt race 1, and lettuce dieback. Two (SM13-R2, SM13-R3) of the four romaine breeding lines are suitable for whole head, salad blend, and spring mix production. One breeding line (SM13-R1) is suitable for whole head production only. The fourth romaine line (RH08-0464) can be used in breeding programs due to its good resistance to downy mildew. SM13-R1, SM13-R2, and SM13-R3 are resistant to dieback. Five leaf lettuce breeding lines (SM13-L1, SM13-L2, SM13-L3, SM13-L4, and SM13-L5) have very high levels of polygenic resistance to downy mildew and can be used for spring mix and salad blend production. The sixth leaf lettuce breeding line (SM13-L6) has resistance to Verticillium wilt race 1 and is suitable for whole head, spring mix, and salad blend production. The leaf breeding lines are resistant to dieback with the exception of SM13-L1.