EFFECT OF NITROGEN AND VARIETIES OF POTATO ON YIELD AND AGRONOMIC N USE EFFICIENCY IN NORTH-WESTERN PLAINS OF INDIA

Studies were conducted at Central Potato Research Station, Jalandhar during 2009-11 to evaluate potato cultivars viz. Kufri Jyoti, Kufri Jawahar, Kufri Bahar, Kufri Sutlej, Kufri Pukhraj, Kufri Pushkar, Kufri Surya and Kufri Gaurav at four N levels (0, 80, 160 and 240 kg N/ ha), to find out the N requirement and agronomic use efficiency of N. Results revealed that Kufri Gaurav recorded maximum yield, agronomic efficiency and net return at all the levels of nitrogen followed by Kufri Pushkar and Kufri Pukhraj. Kufri Surya yielded minimum with least agronomic efficiency at all the levels of nitrogen. Kufri Gaurav proved to possess high tolerance to N stress and was the most nitrogen efficient variety followed by Kufri Pushkar and Kufri Pukhraj. This variety can be useful for resource poor farmers as this produces higher yield compared to other released varieties even at lower doses of N.