Vol. 122 (2009): Proceedings of the Florida State Horticulture Society
Vegetable

Preliminary data on phosporus soil test index validation in southwest Florida

Kelly T. Morgan
UF/IFAS
Shinjiro Sato
UF/IFAS
Eugene McAvoy
UF

Published 2009-12-01

Abstract

The soils of the C-139 Basin were found to have higher pH and very high Ca concentrations compared with similar soils in other Florida locations. These conditions result in precipitation of fertilizer P, rendering it unavailable for crop uptake. Soil test results indicated that the soil samples at the beginning of each season of a three-year fi eld demonstration project were high or very high in extractable soil P using Mehlich 1 extractant and would indicate that no additional fertilizer P should be required for optimum crop production. Green bean (Phaseolus vulgaris L.) biomass significantly increased with increased fertilizer P rate in fi ve of the nine crops grown during the demonstration project. Likewise, green bean yield data of large pod size increased with increased fertilizer P application in seven out of nine crops grown. Tomato (Solanum lycopersicum L.) biomass and yield was less affected by fertilizer P applications compared with green bean. No tomato biomass increase with increasing fertilizer P rate was observed over the 3 years. However, delay in tomato fruit maturity with reduced fertilizer P application was suggested by an increase in large fruit production at the first harvest and an increase in large fruit production at the third harvest.