The Influence Of Organic Manure Sources And Rates On The Growth And Yield Of Sweet Potato (Ipomoea Batatas (L.) Lam) Varieties In An Ultisol Of South Eastern Nigeria

ABSTRACT

Field experiments were carried out at the Michael Okpara University of Agriculture, Umudike teaching and research farm to investigate the growth and yield response of two sweet potato varieties (TIS — 87/0087 and Ex-Igbariam) to rates 0, 10, 20 and 30 t/ha and sources (poultry, pig and goat) manui es in the wet seasons of 2006 and 2007 The experiments were 2 x 3 x 4 factorial in randomized complete block design with three replications Growth paiameters such as number of leaves, vine length were similar among the manure rate but were higher than when there was no manure application. Similarly, yield and yield components such as the total number of tubers, marketable and total tuber yields (t/ha) of sweet potato increased with the rate of manure application but declined after 20 flha. Growth parameters were again high with poultry manure than other manure sources (Pig and Goat) Similaily, yield and yield components were also higher with poultry manure TIS — 87/0087 yielded higher in marketable and total tuber yield than Ex — Igbariam.