Tillage, cover cropping, and nitrogen fertilization influence tomato yield and nitrogen uptake

Management practices can influence tomato (Lycopersicon esculentum Mill.) yield and N uptake. The effects of tillage (no-till, chisel plowing, and moldboard plowing), cover crop [hairy vetch (Vicia villosa Roth) vs, none], and N fertilization (0, 90, and 180 kg.ha(-1) N) on transplanted tomato yield and N uptake were studied in the field from May to August in 1996 and 1997 on a Norfolk sandy loam (fine-loamy, siliceous, thermic, Typic Kandiudults) in central Georgia. Plowing increased fresh and dry fruit yield and N uptake in 1996 and N fertilization increased yield and N uptake in 1996 and 1997. Plowing also increased stem and leaf dry weights and N uptake from 40 to 118 days after transplanting (DAT) in 1996. Fertilization increased stem weight and N uptake with or without hairy vetch from 54 to 68 DAT in 1996 and stem and leaf weights and N uptake at 68 DAT in 1997. Both hairy vetch and N fertilization increased leaf N concentration in 1997. Recovery of N by the plants was lower with hairy vetch than with N fertilization, but was similar to or greater with 90 than with 180 kg.ha(-1) N. We conclude that reduced tillage, such as chisel plowing, with 90 kg.ha(-1) N can sustain tomato yield and N uptake, with reduced potentials of sediments and/or NO3 contamination in surface and groundwater.