Extracción de macronutrientes en dos variedades de lechuga (Lactuca sativa L.) bajo sistema hidropónico

Abstract

Lettuce occupies a prominent place in the national economy as one of the most demanded and valued horticultural crops in consumer markets. In this context, the objective of this research was to evaluate the extraction and recovery efficiency of nitrogen (N), phosphorus (P), potassium (k), calcium (Ca) and magnesium (Mg) in two varieties of lettuce (crespa and capitata) using a hydroponic system. Treatments consisted of doses of 1; 1.5; 2 and 2.5 ml/L of stock solution, which contained specific amounts of nutrients (46.01 N, 23.4 P, 60.5 K, 39 Ca, 14 Mg, 11.43 S, 1 Fe, 0 0.13125 B, 0.0525 Zn, 0.0625 Cu g/L). Variables such as the concentration of nutrients in leaves, the extraction and the recovery efficiency of N, P, K Ca and Mg were analyzed. The results showed that the highest concentration and extraction of nitrogen in the lettuce leaves was obtained by applying 1 ml of the mother solution, while for P, K, Ca and Mg the highest values were observed with an application of 2 ml of the stock solution. As for the varieties, no significant differences were found in the concentration of P, K and Ca in the leaf, while the crespa variety presented a higher concentration of N than the Mg variety Capitata. On the other hand, the extraction of all the evaluated nutrients was greater for the crespa variety, which suggests that this type of lettuce requires a greater amount of nutrients to reach its maximum yield potential. In terms of nutrient recovery efficiency, it was observed that the low doses (1 ml of the stock solution) showed the highest values, except for phosphorus, whose efficiency was higher with an application of 2 ml of the stock solution. The crespa variety also demonstrated greater efficiency in the recovery of the applied nutrients.