Effect of Plant density and Fertilizer Application Rates on Growth, Fruit Yield and Quality of Tomato (Solanum lycopersicum L.) in Greenhouse Condition

Plant density and fertilization are key practices for improving the fruit quality and yield of vegetables grown in greenhouses. The experiment was performed to investigate the effects of density and fertilization on the fruit yield and quality, economic efficiency of Solanum lycopersicum L. at Duc Trong district of Lam Dong province. The density (50,000; 33,000; 25.000 plants ha-1) and the fertilizer rates (240N – 100P2O5 – 275K2O; 300N – 125P2O5 – 344K2O; 360N – 150P2O5 – 413K2O kg and 420N – 175P2O5 – 482K2O kg ha-1) were studied in a completely randomised split plot design with three blocks. The fertilizer rate (420N – 175P2O5 – 482K2O kg ha-1) was produced the highest height (562.39 cm), fruit setting rate (69.87%), number of fruit per plant (95.65 fruits), average fruit weight (106.37 g), fruit yield (441.11 tons ha-1) and marketable fruit yield (204.31 tons ha-1). The density (25,000 plants ha-1) gave the highest fruit setting rate (75.35%), number of fruit per plant (94.84 fruits), average fruit weight (113.24 g), individual fruit yield (10.02 kg per plant) and fruit yield (501.17 tons ha-1). The combination of density (25,000 plants ha-1) and fertilizer rate (420N – 175P2O5 – 482K2O kg ha-1) have the highest fruit yield (613.5 tons ha-1), marketable fruit yield (223.91 tons ha-1) and rate of return (2.44). In addition, this combination was the best density and fertilizer level management strategy for greenhouse-grown Lahay 334 tomato cultivar in Lam Dong province, Vietnam.