2018 ASHS Annual Conference

The right placement of phosphorous (P) fertilizer can help overcome P fixation in calcareous soils. Banding application, including surface and deep banding, concentrates P fertilizer in narrow zone to provide higher nutrient concentration and less P fixation than broadcast application. The surface banding is preferred in vegetable production since it is a simple field application method. However, the movement of P to the root zone becomes a major concern when P is applied as surface banding. Thus, the objective of this experiment was to compare surface banding with deep banding based on the growth and yield of tomato (Solanum lycopersicum, cultivar Ridgerunner) grown on a calcareous soil. One field trial was conducted during the winter growing season of 2015 in Homestead, FL using plasticulture system with drip irrigation. Treatments included control (without any P addition), deep banding (78 kg ha^-1 of P, incorporated into 4-inch deep soils after surface banding), and surface banding (78 kg ha^-1 of P, applied in two bands with 2-inch width and 6 inches away from the bed center). Data collection consisted of leaf tissue P concentration (LTPC), total dry-weight biomass (TDB), total P uptake (TPU), fruit yield, and postharvest qualities. There were no significant differences in LTPC between deep and surface banding and both methods resulted in optimum LTPC during the season. Neither TDB nor TPU were significantly affected by the treatments. Deep and surface banding resulted in significantly higher total season extra-large fruit yield than the control, however, there were no significant differences between the two methods. Tomato postharvest qualities, including exterior color, pH, and total soluble solids content, were not significantly affected by the treatments. Consequently, surface banding can be an viable option to apply P fertilizers for drip irrigated tomato on the calcareous soils.