Dosage of triple 18 water soluble fertilizer on the growth of lettuce cultivar “Great Lakes 118” under artisanal hydroponics

Abstract

In order to evaluate the dose of fertilizer in the growth of lettuce “Great Lakes 118” cultivar, trials were established in conditions of artisanal hydroponics, in the experimental area of the Juanico Campus of the Universidad de Oriente, Venezuela. Sixteen 50 x 100 x 10 cm floating bed cultivation tables of 50 L capacity were built, which were made of wood, lined internally with 10-micron black plastic. Polystyrene sheets of 2.54 cm thickness, perforated and filled with foam rubber for the support of the plants, were used to fix the seedlings in the sheet. The treatments consisted of four doses of 18-18-18 (SOLUB®), per liter of water: T₁ =2 g; T₂ =3 g; T₃ =4 g; and T₄ =5 g, with four repetitions. The experimental design was completely randomized; each cultivation table or experimental unit had 32 lettuce plants. Five evaluations were made at weekly intervals and quantified: height, fresh and dry weight of the foliage, fresh and dry weight of the roots, root volume and pH. The results were statistically analyzed and compared by the Tukey test at 5% probability. The treatment of 2 g of triple 18 per liter of water presented the best ranges of agronomic value for the variables studied. The 18-18-18 fertilizer as the only source of nutrients in artisanal hydroponic culture covered the requirements of lettuce. At the doses evaluated, the pH remained stable and within the ideal range of growth of the culture.