Effect of potassium and zinc on growth, yield and economics of sweet potato (Ipomoea batatas L.) cv. CO-34

Abstract

A field experiment was conducted to study the effect of different levels of potassium and zinc on growth, yield and economics of sweet potato. The experiment was laid out on clay and loam soil by adopting randomized block design with factorial technique (FRBD). The sixteen treatments consisted of combination of four levels of po-tassium (0, 80, 100 and 120 kg/ha through muriate of potash and four levels of foliar zinc (control i.e. water spray, 10, 20 and 30ppm) through zinc sulphate. The individual application of potassium 120 kg K2O/ha significantly in-creased the number of tubers per plant (4.60), average weight of tuber (275.31 g), length of tuber (16.77 cm), diam-eter of tuber (5.69 cm), tuber yield per plot (9.71 kg), tuber yield per hectare (49.04 t) respectively as compared to control. With the foliar application of zinc (30 ppm) significant increase in number of tubers per plant (4.18), average weight of tuber (234.73 g), length of tuber (18.12 cm), diameter of tuber (5.16 cm), tuber yield per plot (8.33 kg) and tuber yield per hectare (42.05 t) was recordedas compared to control. The treatment combination (120 kg K2O+30ppm Zn) recorded the maximum yield parameters i.e. chlorophyll content (37.00 mg/100 g), average weight of tuber (302.17 g), length of tuber (19.82 cm), diameter of tuber (5.97 cm), maximum tuber yield per plot (11.02 kg), tuber yield per hectare (55.67 t) and benefit-cost ratio (B: C ratio) of 4.22:1.While, the treatment (120 kg K2O+30ppm Zn) had the maximum number of tuber (4.86), minimum number of tuber was recorded in control. From the experi-ment, it appeared that application of potassium and zinc can be used to improve yield and higher net monetary re-turns of sweet potato.