Shading and substrate in the production of <i>Lactuca canadensis L</i>. seedlings

Abstract

The production of L. canadensis seedlings at levels of shading and doses of bovine manure added to the substrate was evaluated. The 3 x 5 factorial design tested three levels of shading 35, 50 and 70% and five doses of manure 0, 15, 30, 45 and 60%. It was evaluated the percentage of emergence and survival, mean time of emergence, shoot and root length, ratio between shoot length and largest root, dry mass of shoots and roots, number of leaves, neck diameter, total chlorophyll content and Dickson quality index. The shading of 50 and 70% favored germination and emergence, however for the development of L. canadensis the shading at 35 and 50% was more efficient. The increase in manure to the substrate gave better growth of the seedlings, in which, the addition of 60% was superior to the other doses