Response of Florunner Peanuts to Planting Dates, Herbicide Sequences, and a Systemic Insecticide

Abstract

Benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine) applied as a preplant incorporated treatment followed by application at the ground-cracking stage (GC) of a mixture of alachlor [(2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide] plus naptalam (N-1-naphthylphthalamic acid) and dinoseb (2-sec-butyl-4,6-dinitro-phenol) significantly increased the yield of peanuts (Arachis hypogaea L. ‘Florunner’). Delaying treatment with the GC mixture for 10 days did not significantly depress peanut yields when averaged over all soils, although exceptions occurred within soil series. Substantial and consistent yield reductions occurred when the herbicide sequences terminated with five repeated applications of dinoseb, especially on the Ruston soil. Late planted peanuts often were more susceptible to intensive herbicide treatments than the early plantings. Beginning intensive sequential treatments with vernolate (S-propyl dipropylthiocarbamate) reduced yields more than when benefin initiated the sequence. Average yields of Florunner peanuts were increased significantly by the insecticide disulfoton (O,O-diethyl S[2-(ethylthio)ethyl]phosphorodithioate) on the Greenville and Ruston soil series, but not on the Dothan soil. The disulfotan x herbicide interaction was not significant. Herbicides interacted more frequently with planting date, treatment time, soil series, and year than did disulfoton.