Evaluación del residuo de cáscara de nuez (Juglans regia L.) en la producción de plántulas de Pinus patula, en vivero

to produce quality plants in the nursery, commercial substrates such as the peat moss, perlite and vermiculite, are used; their cost is high and significantly reduces profit margins; thus, there is a need to find alternative substrates. the shell of the walnut (juglans regia l.) is a residue without use in production; yet it has important nutrients that can be used by plant organisms. this study evaluated the initial growth of pinus patula produced in the nursery, using compost of walnut shell with vermiculite and perlite, gradually replacing the peat moss. a completely randomized design was used to compare 4 treatments based on nutshell + perlite and vermiculite, in proportions ranging from 0% to 80% walnut shell, and the mix of commercial substrates. at 7 and a half months of age, the seedlings that developed in treatment 1, control mixture (peat moss 33% + vermiculite 33% + perlite 33%) and treatment 4 (nutshell 33% + vermiculite 33% + perlite 33%) showed higher values in the variables: height, diameter, shoot dry weight, root dry weight and total dry weight. the relation shoot/root and the slenderness ratio did not differ among the 4 treatments. the highest value of the dickson quality index was for the control (0.25 g.cm-1), followed by treatment 4 (0.24 g.cm-1), without statistical differences. the walnut shell allows to produce healthy seedlings, making it useful as an alternative substrate for production in nursery plants, reducing production costs and contributing to the forest production sector.