Evaluation of the development of Lactuca sativa seedlings on different forms of shading

Abstract

Healthy seedling using plays key role in quality-vegetable production processes, since it directly affects the productive performance of crops. The aim of the present study is to assess the influence of different shading levels on lettuce seedling development. Two lettuce cultivars (green-leaf lettuce cv. Amanda and iceberg lettuce cv. Lucy Brown) planted in Styrofoam trays, and four culture environments (open sky, 50% shading, 70% shading and transparent plastic canvas) were used in the experiment, which followed a completely randomized block design, at 4x2 factorial arrangement. The following parameters were evaluated: shoot and root length, fresh shoot and root weight, dry shoot and root weight, and number of leaves. Results have shown that the effects of high temperature and light incidence on plants can be minimized through shading screen using, since shading accounted for enabling higher shoot and root growth. Thus, it was possible obtaining stronger seedlings that, consequently, were more resistant to mechanical damages likely to take place at transplantation time.