Nutrition Assessment of N-P-K in Mint (Mentha spicata L.) Cultivated in Soilless System

Abstract

Aims: The objective of this study was to determine the nutrient removal of N, P and K in the biomass production of mint plants at the harvest time. Study Design: A randomized complete block experimental design with five replicates and a time series arrangement was used. Data were adjusted by polynomial regression models with SAS statistical analysis system. Place and Duration of Study: The experiment was set up in a shade house (35% shade) located in Xalisco, Nayarit in western Mexico during the spring-summer of 2011, using a commercial variety of mint. Methodology: The harvest days were 20, 40, 60, 80, 100 and 120 days after transplant (DAT), dates on which shoots 15 cm in length, the required size in the international market, were obtained. Steiner solution was used at five concentration levels: 25, 50, 75, 100 and 125%. The growth medium was volcanic slag with 0.3-1 cm granulometry. Plant height, fresh and dry plant biomass and stem diameter were assessed at each sampling date. Nutrient removal of nitrogen, phosphorus and potassium was determined in the different samples in order to understand the absorption dynamics of these elements under commercial management. Results: The results showed that the 100% nutrient solution (NS) concentration increased plant height (PH) by 34% during the first five cuts. Stem diameter (SD) had no significant differences among treatments. Above-ground fresh biomass (AGFB) and above-ground dry biomass (AGDB) were greater in the 100% NS treatment. Nitrogen, P and K (mgkg-1) removal was dependent on the ionic concentration of the nutrient solution. Conclusion: The concentration of the nutrient solution modified fresh and dry biomass production in mint plants. The concentration of the nutrient solution must be increased for optimal yield.