Texas Panicum (Panicum texanum) Control in Strip-Tillage Peanut (Arachis hypogaea) Production

Abstract

Abstract Studies were conducted from 1999 through 2001 in Georgia to develop Texas panicum management systems in strip-tillage peanut production into a killed rye cover crop. The experimental design was a split-plot with four replications. Main plots were preemergence (PRE) herbicides for annual grass control—ethalfluralin, pendimethalin, metolachlor, alachlor, dimethenamid, and a nontreated PRE control. All plots were irrigated immediately after PRE applications to activate herbicides. Subplots were postemergence (POST) graminicides applied 28 d after peanut emergence—sethoxydim, clethodim, and a nontreated POST control. POST graminicides were applied with a crop oil concentrate. None of the PRE herbicides alone adequately controlled Texas panicum in strip-till peanut production, even with optimum activation with irrigation. Sethoxydim and clethodim controlled Texas panicum at least 91%, regardless of PRE treatments. Peanut yields were greater where ethalfluralin or pendimethalin PRE were applied sequentially with a POST graminicides, compared to PRE herbicides or POST graminicides alone. This suggests that, while POST graminicides effectively control Texas panicum, the reduced efficacy of dinitroaniline herbicides is still beneficial. The additional cost of a POST graminicide needs to be factored into production budgets for strip-tillage peanut production.