Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: December 13, 1999
Publication Date: N/A
Technical Abstract: The western corn rootworm is a major insect pest in continuous corn, but no viable alternatives to insecticides are available for its control. From 1994 to 1996, seven strains of corn with reduced corn rootworm damage were identified. Since utilization of these strains would likely require backcrossing into elite germplasm, a diallel set of crosses, including the seven resistant lines and inbred lines B37 and Mo47, was formed to determine which strain had the best potential for contributing corn rootworm resistance to progeny. Each parental line was crossed reciprocally with each of the other eight. Parental germplasm, available crosses, and resistant and susceptible checks were evaluated at three central-Missouri locations in 1997. Ten of the best crosses in the diallel from 1997 were selfed in a 1997-1998 winter nursery and seed from three ears for each cross (30 ears total) were evaluated along with checks in 1998. As indicated by a significant, negative general combining ability effect, three of the parents contributed corn rootworm resistance to their respective progeny. Specific combining ability effects for these crosses were not significant. In 1998, one entry had significantly less damage than all other entries. The entry TL92A PAR 1779 60-4 NGSDCRW1(S2)C4-15- 2S2 was the best of all entries evaluated in 1997 and 1998, had significantly less damage than the resistant check in both years, and represents a new source of native resistance to feeding damage caused by western corn rootworm larvae. Data from 1999 will also be discussed.