Tomato fruit yield response to nitrogen source and percentage of drip‐ or band‐applied nitrogen associated with leaf potassium concentration

Abstract

Field experiments were conducted during the spring and fall of 1994 to evaluate two nitrogen (N) sources [ammonium nitrate (AN) and polymer‐coated urea (PCU)] and five levels of drip‐ or band‐applied N on the yield of drip irrigated ‘Solar Set’ tomatoes (Lycopersicon esculentum Mill). Early‐season yields obtained with PCU were similar to or greater than yields obtained with AN. Highest yields of large fruit early in the season were produced with 100% preplant‐applied AN or 100% band‐applied PCU. Total‐season yields were greater with AN than PCU and were not affected by placement of N. Increasing the percentage of drip‐ or band‐applied N resulted in leaf N concentrations that were inconsistent with trends in marketable fruit production; however, trends in leaf K concentration early in the season were similar to those of early‐season large fruit yields.