EFFECT OF POTASSIUM ON THE YIELD AND TUBER SIZE OF TWO VARIETIES OF POTATO (Solanum tuberosum L.)

Abstract

A field experiment was conducted at the Horticultural Farm of Hajee Mohammed Danesh Science and Technology University, Dinajpur during November, 2006 to February, 2007 to study the effects of different levels of potassium on the yield and size of potato tubers cv. Diamant and Granola. The treatments of the experiment comprised of eight combinations of those two varieties and four levels of potassium viz. 0, 90, 150 and 210 kg K,Oha™. Between two varieties, Diamant was found to be characterized as the higher yielder (22.45 t/ha) than Granola (18.75 t/ha). The largest tubers (grade D; >55mm diameter) were obtained from the variety Diamant (number 8.57% and weight 12.55%). The smallest tubers were obtained from the variety Granola (number 8.23% and weight 8.66%). It was revealed that the variety Diamant was superior performer over Granola regarding yield contributing attributes namely plant height, number of leaves, potato tubers per hill and dry matter content. Regarding main effect of potassium, significant influence was observed on all the growth and yield contributing characteristics, except days required for 80% emergence of plants. The highest yield of potato (24.49 t/ha) was obtained from the application of 210 kg K,Oha”. The control treatments for the two varieties with no potassium gave poor results in all respects. In terms of the combined effect of variety and potassium fertilizer, the highest yield (27.26 t/ha) and the largest grade size D (55mm diameter) tubers were obtained from the variety Diamant with 210 kg K,Oha'. The best economic return was also obtained from the same treatment combination showing the benefit cost ratio (BCR) of 2.83.