Production of lettuce (Lactuca sativa) seedlings in granulate rockwool and expanded perlite for use in hydroponics Producción de plantines de lechuga (Lactuca sativa) en lana de roca granulada y perlita expandida para uso en hidroponía

Abstract

The quality of lettuce (Lactuca sativa) seedlings is closely dependent on the substrate and the management practice during the transplant to the hydroponic system. This seed bed process may affect the normal development of the seedlings by affecting the post-transplanting period, potentially causing root stress, influencing establishment and even leading to seedling loss. An important criterion when choosing either a single or mixed substrate is the ability to provide for both growth and establishment of the seedlings in the hydroponic system. The main objective of this study was to evaluate the effect of granulated rockwool substrate (Agrolan™, Compañía Industrial El Volcán S.A., Santiago, Chile), expanded perlite A6 (Harbolite Chile Ltda., Santiago, Chile) and a mixture of both substrates on seedling growth, development and establishment after transplant of lettuce seedlings to an NFT-modified hydroponic system. Growth analyses were performed at the 2 to 3 true leaf stage of the lett