Effect Of Cow Dung And Npk Fertilizer On Soil Properties, Nutrient Uptake And Tuber Yield Of Sweet Potato (Ipomoea Batatas) In South Eastern Nigeria

ABSTRACT

 Investigations were carried out at two different locations (Uturu and Umudike) during the 2004-planting season, to evaluate the effect of cow dung and NPK fertilizer (15:15:15) on soil properties, nutrient uptake and yield of sweet potato (Ipomoea batatas). The experiment was a randomized complete block design (RCBD) with four replications. The treatments consist of 3.7t/ha cow dung, 400kg/ha NPK fertilizer, 1.9t/ha cow dung + 200kg/ha NPK fertilizer, 0.9t/ha cow dung + 300kg/ha NPK fertilizer, 2.8t/ha cow dung + 100kg/ha NPK fertilizer and control (which did not receive any treatment). The treatments significantly (P

<0.05) increased organic matter, organic carbon, available P, exchangeable K and ECEC compared to control at both locations. In both locations, application of 0.9t/ha cow dung + 300kg/ha NPK fertilizer gave the highest N, K, Ca, Na and Mg uptake. This was followed by application of 1.9t/ha cow dung + 200kg/ha NPK fertilizer. Also, application of 0.Yt/ha cow dung + 300kg/ha NPK significantly (P><0.05) increased sweet potato leaf area and leaf number. Application of 1.9t/ha cow dung + 200kg/ha NPK increased sweet potato vine length, number of branches as well as yield index in both locations. Application of 1.9t/ha cow dung + 200kg/ha NPK fertilizer recorded the highest sweet potato tuber yield of 8.9t/ha at Umudike and 3.8t/ha at Uturu. From the results obtained, application of 1.9t/ha cow dung + 200kg/ha NPK fertilizer is recommended xii for sweet potato production in Umudike while application of O.9t/ha cow dung ± 300kg NPK fertilizer is recommended in Uturu. >