PRODUCTIVITY OF SWEET POTATO (IPOMOEA BATATAS (L.) LAM) AS AFFECTED BY NPK FERTILIZER RATE, INTRA-ROW SPACINGS AND VINE CUTTING LENGTHS IN THE NORTHERN GUINEA SAVANNA AGROECOLOGICAL ZONE OF NIGERIA
A two year field study was conducted during the rainy seasons of 2013 and 2014 at the research farm of institute for Agricultural Research, Ahmadu Bello University, Samaru Zaria North Western Nigeria (110 11!N: 70 381E and 686m above sea level) to determine the effects of NPK fertilizer rate, intra-row spacing and vine length on the productivity...