pnut pnut Peanut Science 0095-3679 0095-3679 American Peanut Research and Education Society 10.3146/i0095-3679-26-1-7 Articles Peanut Seedling Response to Dinitroaniline Herbicides Applied Preplant Incorporated and Preemergence1 W. C. Johnson III * and B. G. Mullinix Jr. 2 Res. Agron., USDA-ARS and Agric. Res. Statistician, Coastal Plain Exp. Stn., Tifton, GA 31793–0748 *Corresponding author (email: cjohnson@tifton.cpes.peachnet.edu).

1Cooperative investigations of the USDA-ARS and Univ. of Georgia. All programs and services of the USDA-ARS and the Univ. of Georgia are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap.

 1 1999 26 1 28 32 American Peanut Research and Education Society 1999 American Peanut Research and Education Society Abstract

Greenhouse studies were conducted in 1995, 1996, and 1998 to measure the effect of preplant incorporated (PPI) and preemergence (PRE) applications of ethalfluralin and pendimethalin on growth of individual peanut seedlings in pots. Herbicide rates evaluated were 0, 0.6, 1.1, and 2.2 kg ai/ha for each herbicide. Parameters measured were time of emergence, seedling height, canopy width, foliage biomass, root length, and root biomass of individual plants. PPI applications were more injurious than PRE applications for all parameters regardless of herbicide. Ethalfluralin PPI inhibited peanut seedling growth more than equivalent rates of pendimethalin PPI. However, peanut seedling responses to PRE applications of ethalfluralin and pendimethalin were generally the same.

 Key Words Arachis hypogaea L; , ethalfluralin; , herbicide phytotoxicity; , peanut injury; , pendimethalin