Vermiliquer as a biostimulant and antioxidant in hydroponic lettuce (Lactuca sativa) production

Abstract

The use of vermiliquers obtained from earthworm in hydroponic crops is well received as alternative for fertilization of leafy vegetables. The vermiliquer boosts growth, defense compounds and increases the uptake of nutrients and minerals by plants. The growth and enzymatic activities related to stress and phenolic compounds were explored in hydroponic lettuce crops treated with different concentrations of vermiliquer. The treatments consisted in three different vermiliquer, a Mesh Vermiwash, a Direct Vermiwash, and the Vermileachate, and its combinations as a complement for complete fertilization. The addition of vermiliquer to hydroponic lettuce affected the leaf and root fresh weight, and reactive oxygen species like superoxide dismutase (SOD) or phenylalanine ammonia-lyase (PAL). Vermileachate (Vl) plus Direct Vermiwash treatment was higher in the first week in leaf and root lettuce, indicating an effect biostimulant. Vl gave the highest enzymatic activity in SOD and PAL, indicating an effect elicitor. In summary, vermiwash proved to improve hydroponic lettuce crop and enzymatic activities related to stress.