Performance Evaluation of Four Novel Cassava (Manihot esculenta Crantz) Accessions to Different Fertilizer Types in Awka, Anambra State, Nigeria

The investigation was carried out on the effects of fertilizer and cassava variety on agronomic characteristics, yield, and disease incidence of four improved cassava accessions. The experiment was carried out at the Teaching and Research farm of Crop Science and Horticulture, Nnamdi Azikiwe University Awka, Anambra State. It was a 4 × 3 factorial experiment with treatments laid out in a Randomized Complete Block Design (RCBD) with three replications. Fertilizer types were NPK 15:15:15 at a rate of 400 kg/ha, poultry manure (PM) at a rate of 50 tons/ha and no application as control. The cassava accessions were TMS539, TMS092, TMS371 and TMS412, obtained from the International Institute for Tropical Agriculture (IITA) in Ibadan, Nigeria. Stems were cut to about 15cm and planted at a spacing of 0.5m apart. The parameters measured were the number of root tubers, total number of rot tubers, weight of tuber (kg), stem girth (cm), node per stand, branching interval, internode spacing (cm), number of branching, plant height (cm), age at branching, disease incidence. Normal agronomic practices were carried out. Results showed that all varieties responded to the application of inorganic and organic fertilizers. Cassava plants that did not receive any fertilizer application (no application) gave the highest number of root tubers (29.7) from TMS412, and the least was from TMS092. The result also showed that there was no significant difference in the effects of fertilizer type on diseases. Results also showed that there was a significant interactive effect of cassava varieties and fertilizer type on branching interval (7.009), Internode spacing (0.6195), number of branching (0.2822), and plant height (17.02) at six months after planting. From the investigation, it could be recommended that for farmers to obtain greater yields with little or no fertilizer application, these cassava accessions should be used, which are characterized by high yield and resistance to disease and pests, as shown from this research.