Defender
1. Defender was developed by recombining two populations selected for having resistance to Phytophthora root rot, with a population having resistance to anthracnose. (All three populations were selected from Thor.) The two Phytophthora resistant populations, THPT-5 and MW-74-4PT, were developed through several cycles of phenotypic recurrent selection in which 26 to more than 100 plants were saved in each cycle. The population having resistance to anthracnose, 74TH-An, was developed through two cycles of selection in which 43 and 50 plants were saved at cycles one and two respectively. Approximately 20% outcrossing to other anthracnose resistant plants occurred following cycle one. A composite of 40% THPT-5, 10% MW-74-4PT and 50% 74TH-An was pollinated under cage isolation to produce MW-76-12 (Syn 2). MW-76-12 was increased to produce K7-28 (Syn 2).
2. Defender has been tested in Iowa, Nebraska, Minnesota, Tennessee, Missouri, Montana and Washington. It is well adapted to the Northern and Central regions of the U.S. where it will be used primarily for hay, haylage and greenchop.
3. Fall dormancy is similar to Saranac-AR. Flower color is approximately 43% light purple, 39% medium dark purple, and 18% dark purple.
4. Defender has resistance to bacterial wilt, moderate resistance to anthracnose, Phytophthora root rot, pea aphid and stem nematode; it has low resistance to spotted alfalfa aphid and Fusarium wilt and tolerance to potato leafhopper yellowing.
5. Seed classes will be breeder, foundation and certified. Adequate breeder seed (Syn 2) has been produced to last the expected life of the variety. Limitation on age of stand for each class will be two, three and five years for breeder, foundation and certified respectively.
6. Certified seed will be available in 1981.
7. Application for plant variety protection is not planned.