Abstract
The study was conducted at the Horticulture Research Centre of the Bangladesh Agricultural Research Institute, Joydebpur, Gazipur during 2005-2008 in order to investigate the effects of B and Zn on the yield and quality of tomato with a view to improving the micronutrient management practices for the crop. The tomato variety BARI Tomato-9 was used for all the experiments, while BARI Tomato-14 and a hybrid (GT016XGT017) were also used for one of the experiments. In two different experiments with varied levels of B and Zn, 2 kg B/ha and 6 kg Zn/ha were found the best. Higher doses of B and Zn resulted negative effect on the yield components, yield and quality of tomato. Independent application of 2 kg B /ha and 6 kg Zn /ha gave the highest yield (87.28 and 88.80t/ha, respectively) and quality of tomato. Application of 2 kg B/ha resulted in higher levels of TSS (5%), ascorbic acid (10.65 mg/100g) and lycopene (69 μg/100g) contents and increased shelf life (15 days). But later experiments showed that, application of 2.5 kg B and 6 kg Zn/ha in combination gave the highest yield and quality of tomato. The highest yield (93.75 t/ha), TSS(4.70%), ascorbic acid (11mg/100g) and lycopene (122 μg/100g) contents, and shelf life (18 days) were noted with 2.5 kg B and 6 kg Zn /ha. On the other hand, application of 2.5 kg B and 6 kg Zn/ha in combination with 100% recommended dose of NPK fertilizers demonstrated even higher yield (95.49 t/ha) and high levels of TSS (4.50%), ascorbic acid (10.95 mg/100g), lycopene (112 μg/100g) and shelf life (16 days). The combination of 2.5 kg B and 6 kg Zn/ha and 20 t cowdung /ha significantly increased the yield attributes, yield and quality of tomato. Further study demonstrated that the application of 2.5 kg B and 6 kg Zn/ha resulted in the highest yield and quality attributes, irrespective of varieties. The hybrid receiving 2.5 kg B and 6 kg Zn/ha gave the highest yield of tomato (101.34 t/ha), but the highest TSS (4.40%), acidity (0.34%), ascorbic acid (11.26 mg/100g) and lycopene content (140 μg/100g) were recorded from the variety BARI Tomato-14 with 2.5 kg B and 6 kg Zn/ha. On the other hand, the highest shelf life (15 days) was recorded from the variety BARI Tomato-9 receiving the stated dose of B and Zn. Economic returns, in respect of net return and BCR, suggested that the application of 2.5 kg B and 6 kg Zn/ha was the most profitable, irrespective of varieties. The highest net return (Tk 2,05,380/ha) and BCR (1.68) were recorded from the hybrid produced with 2.5 kg B and 6 kg Zn /ha. It is concluded that, high yield and good quality tomatoes can be obtained with the application of 2.5 kg B and 6 kg Zn/ha, in addition to 20 t/ha cow dung and 253 kg N, 203 kg P, and 151 kg K/ha (550 kg Urea, 450 kg TSP, and 250 kg MP/ha) under BARI farm conditions, Joydebpur.