EFFECT OF POTASSIUM SOURCES AND BIOCHAR LEVELS ON THE YIELD AND QUALITY OF POTATO

Abstract

A field experiment was conducted at the experimental field of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka-1207 during the period from November, 2019 to March, 2020 in Rabi season to find out the response of different source of potassium fertilizer and different biochar levels on growth, yield and quality of potato. The experiment had two factors. factor a: potassium: 3 sources; K₁: Muriate of potash (MoP or KCl), K₂: Potassium phosphate (KH₂PO₄) and K₃: Potassium sulfate (K₂SO₄) and factor B: Biochar: 4 levels; B₁: 1.25 t ha⁻¹, B₂: 2.50 t ha⁻¹, B₃: 3.75 t ha⁻¹ and B₄: 5.00 t ha⁻¹. The potato variety was BARI Alu-29 (Courage). The experiment was laid out in a Randomized Complete Block Design (RCBD) with three (3) replications. Total 36 plots were made for the experiment with 12 treatments. Source of potassium fertilizer and/or biochar showed significant effect on different morphological, yield and qualitative characters of potato. The maximum number of tubers hill⁻¹ (7.44), the maximum weight of tubers hill⁻¹ (266.37 g), the highest tuber yield (26.64 t ha⁻¹), the maximum marketable yield (19.07 t ha⁻¹) and the highest specific gravity of tuber were recorded (1.058 g cm⁻³), the maximum tuber dry matter (21.73%) and the highest starch content on potato (16.77 mg g⁻¹ FW) were recorded from B 4

(5.00 t ha⁻¹) treatment. In 36 treatment of combinations, the maximum weight of tuber hill⁻¹ (286.00 g), the highest tuber yield (28.60 t ha⁻¹) and the maximum marketable yield (20.48 t ha⁻¹) were observed in KH 2 ii PO 4 and 5.00 t ha⁻¹ biochar (K 2 B 4 ) treatment combination. Application of KH 2 PO 4 as the source of potassium fertilizer with 5.00 t ha −1 of biochar combination seemed to be more suitable for getting higher yield. But when considering quality attributes, the combination of Potassium sulphate with 5.00 t ha −1 biochar exhibited highest dry matter content (22.67%), maximum starch content (17.50 mg/g FW), whereas, minimum TSS and reducing sugar content. It is concluded that the application of Potassium phosphate (452.19 kg KH₂PO₄ ha −1 ) and 5.00 t ha of biochar is suitable for higher yield and the application of Potassium sulphate (288.60 kg K₂SO₄ ha

−1 ) and 5.00 t ha −1 biochar is applied for good quality potato.