Tillage Variables for Peanut Production

Abstract

Abstract Effects of minimum tillage (MT) production techniques on peanut (Arachis hypogaea L.) root growth and yield were unknown. Field experiments were therefore conducted during 1984 near Williston and Marianna, FL and during 1985 near Williston and Jay, FL to evaluate effects of surface and subsurface tillage on peanut production. Soil types were a Zuber loamy sand (fine, mixed hyperthermic Ultic Hapludalf) at Williston, a Chipola sandy loam (loamy, siliceous, thermic Arenic Hapludult) at Marianna, and a Red Bay sandy loam (fine, loamy, siliceous, thermic Rhodic Paleudult) at Jay. The Sunrunner peanut cultivar was planted using a modified twin 23 cm row spacing and seeded at a rate of 140 kg/ha. Eight tillage systems that included combinations of conventional tillage, strip-tillage, and no-tillage with and without subsoiling or subsurface slitting were evaluated. Peanuts germinated and grew well except in no-tillage plots that received no subsurface tillage. Without surface or subsurface tillage there was not sufficient soil disturbance to insure proper seed-soil contact or seed cover. Generally, plots that received some degree of conventional tillage yielded better than plots with no surface preparation (4090 vs. 3760 kg/ha avg.). Minimum tillage plots yielded numerically less than conventional plots but in only a few cases were significant differences in yield noted. At most locations, minimum tillage plots that received no subsurface tillage developed a “lazy root syndrome” in which the few roots produced were quite shallow and grew near the soil surface. These treatments yielded less (3680 vs. 4010 kg/ha avg.) than those with conventional seedbed preparation or the minimum tillage treatments receiving subsurface tillage. Root strength and penetration measurements roughly reflect the same trends as peanut yields. The slit-tillage system resulted in peanut yields equal to or better than those obtained with chisel point subsoiling. Slitter wear and breakage problems were encountered but overall, the subsurface slit system appears to be a functional alternative to chisel point subsoiling.