Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/31/2002
Publication Date: 1/1/2003
Citation: Abel, C.A., Tyler, J.M. 2003. Registration of DT98-2448 soybean germplasm resistant to defoliating insect damage. Crop Science. 43:1136 - 1137. Interpretive Summary: Soybean growers in the southeastern United States suffer economic losses from leaf-feeding insects. DT98-2448 soybean germplasm, resistant to leaf-feeding insect damage, was released by the Agriculture Service, United States Department of Agriculture in July 2000. This germplasm is a product of a soybean breeding program designed to develop plants that resist insect feeding. Resistant soybeans will reduce the need to us chemical pesticides to control these pests, thus, saving growers money, providing a safer product for the consumer, and reducing harm to the environment. DT98-2448 resisted insect leaf feeding in an experiment that was designed so that the tested soybeans would be exposed to a high number of damaging insects. DT98-2448 was developed to be grown in the heavy clay soils of the lower Mississippi River Valley. DT98-2448 will provide a useful source of resistance that will allow public and private scientists sto develop varieties of soybean that will produce well in clay soils while being resistant to defoliating insects.
Technical Abstract: During most years, soybean (Glycine max L.) growers in humid sub-tropical i.e. southeastern United Staes) and tropical regions suffers economic losses to defoliation from larval insect pests in the order Lepidoptera. DT98-2448 soybean resistant to defoliating insect damage was released by the Agricultural Research Service U.S. Department of Agriculture in July 2000. This germplasm is derived from the cross, PI 229358 x DP3589, and is the product of several breeding cycles aimed at combining a high level of insect resistance with agronomic traits superior to that of the source of resistance. The source of resistance carried by DT98-2448 is PI 229358, a maturity group VII soybean that is resistant to insect defoliations and originated from Japan. DP3589 is a commercial cultivar adapted to the clay soils of the lower Mississippi River Valley. In 1998, 200 F5:F6 progeny rows were grown in the field at Stoneville, MS and 24 Pseudoplusia incudens (Walker), were selected for advancement. In 1999, the 24 entries were evaluated for leaf feeding damage by introducing a very high population of velvetbean caterpillar, Anticarsia gemmatalis Hubner, in a 0.6 hectare field cage that excluded indigenous insects. Per cent defoliation of DT98-2448 (53%) was similar to that of the resistance source, PI 229358 (50%), and much less than that of susceptible cultivars Bedford (93%) and TracyM (93%). Seed yield of DT98-2448 (3440.6 kg ha-1). was significantly less than that of UARK-5798 (3830.4) and P9594 (3978.2 kg ha-1). This germplasm represents an improved parental source for breeders that offers defoliating insect resistance with yield potential in heavy clay soils.