Planting density and humic substances in growing tomato (Solanum lycopersicum L.)

Tomato is one of the most popular vegetables, so it is very important to carry out research to ensure high quality fruit and yield. The objective of this work was to evaluate different doses of humic and fulvic acids on the growth and yield of tomato cultivated with different planting densities. The experiment was carried out on the farm of the State University of Goias (UEG), Ipameri Campus. The spacings of 0.30 and 0.50 m between plants were adopted, corresponding, respectively, to the populations of 33,333 and 20,000 plants ha(-1); with different rates (0, 20, 40, 60 and 80 L ha(-1)) of humic and fulvic acids. The experimental design was randomized blocks in a factorial scheme 2 x 5 (spacings x acid rates) with four replications. The data were submitted to analysis of variance and the means were compared by the Tukey test at 5% probability. The productivity of the tomato was higher in the spacing of 0.50 cm, and the increasing doses of humic and fulvic acids had a positive influence on the chlorophyll content and firmness of the table tomato. It is concluded that for the adequate cultivation of the Santy Hybrid, it is recommended the planting density of 20,000 ha(-1) plants and increasing doses of humic substances, thus guaranteeing high productivity and fruit quality.