With the aim of evaluating the effect of the use of different organic materials on the standard substrate for the production of cofee seedlings (Coffea arabica L.) in small plastic tubes, an experiment was installed at a seedling production nursery at the Agrotechnical Federal School of Uberlândia, in the period of July of 2005 to January of 2006. The randomized block design was used, in a factorial scheme 3 x 6, with four replications, the factors being: three sources of organic material (mature bovine manure, mature turkey bed and mature tobacco residue) and six proportions of these materials in the original substrate (0, 20, 40, 60, 80 and 100%). The parcels were constituted by six small plastic tubes with volumetric capacity of 120 mL. In the fertilization of the substrate a slow-releasing fertilizer (osmocote) was used, with the formula NPK 15-09-12, applied in homogeneous mixture in the dose of 1 g of the commercial product per container and the commercial product Bioplant-coffee was used as standard substrate. The characteristics evaluated were: plant height, stem diameter, number of leaf pairs, leaf area, and root and shoot dry matter weight. All data were submitted to the analysis of variance, with application of the test of F, considering the significance in the traditional levels of 5% and 1% of probability and, for comparison of the averages of the sources of organic material, the test of Tukey was applied at 5% of probability, while the analysis of regression was performed to evaluate the proportions of the organic material. It was concluded that the addition of 40% of turkey bed to the standard substrate, regardless the mixture proportions, hindered seedling development; mature bovine manure added to the standard substrate, independently of its proportion, was prejudicial to the development of the seedlings; the tobacco residue was also prejudicial to the development of the seedlings and in the concentration higher than 60% it provoked the death of the plants.
Seedlings; small plastic tube; artificial substrate; organic materials
