Efficacy of Organic Manures on the Productivity, Shelf-life and Economic Efficiency of Tomato Varieties in a Long-term Fertilized Field by Chemical Fertilizers

The study was undertaken to identify the effect of organic manures (OMs) on the productivity, shelf-life, and economic efficiency of tomato varieties for minimizing the continuous application of chemical fertilizers in Bangladesh. The experiment was conducted during the dry season from October 2012 to March 2013 in an experimental field of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. The experiment was laid out with completely randomized design with 3 replications. Three tomato varieties (BARI Tomato 15, BARI Tomato 14, and BARI Tomato 2) were grown in plots with different treatment viz. cow dung (CD), poultry manure (PM), and vermicompost (VC) containing 170 kg ha-1 of N2, and the results were compared with non-fertilized plots (control). The harvested fruits were kept at an ambient temperature without bagging, kept at an ambient temperature in a polyethylene bag, or kept at 10⁰C in a polyethylene bag, and the shelf-life of each fruit was monitored. Moreover, cost-effectiveness was calculated based on common tomato production practices of Bangladesh. The effect of OMs on the vegetative growth was largely depend on the cultivars. Differing from the vegetative growth, the total fruit yield significantly increased with the application of PM and VC, irrespective of the cultivar, while the single fruit weight and fruit number per plant varied largely depending on the cultivar. The shelf-life was also significantly prolonged by the application of PM and VC. On the other hand, the effect of CD on the fruit yield and shelf-life was relatively low. The results of economic analysis revealed that the benefit-cost ratio was low in CD and VC because of the low fruit yield and high cost, respectively. Among the treatment combinations, PM x BARI Tomato 15 showed the best result not only from the viewpoint of fruit yield and storability but also from that of the benefit-cost ratio, indicating the effectiveness of this combination as an alternative option for improving the continuous application of chemical fertilizers on Bangladesh soil.