Influence of plant density and time of fertilizer application on growth characteristics, nutrient uptake and yield of tomato

Abstract

In a factorial experiment to investigate the combined effects of plant density and time of split application of fertilizer, 4 spacings and 3 fertilizer treatments were employed. Plant populations were varied between 24,000 and 54,000 per ha. Equal amounts of NPK were applied in different split applications and at specific physiological stages. Time to 50% flowering was delayed by fertilizer application as well as by wide within-row spacing. Total leaf N and P content declined with all treatments between flowering and mature-green stage of fruits, but increased again at table-ripe stage. Leaf K content remained constant throughout the growth period. Two-split applications of NPK, one at 2 weeks after transplanting to the field and the other at fruit set, were more beneficial than either no fertilizer or 3-split applications of equal amount of fertilizer, when the third application was at mature-green stage. This was indicated by higher fruit yields with 2-split applications. Highest fruit yields were obtained when tomatoes were planted either at 30.5 cm × 91 cm single-row spacing, or at 45.5 cm × 122.0 cm, double-row spacing, both giving 36,000 plants per hectare. Fruit yields were reduced at lower and higher population densities.