Effects of Tillage Practices on Growth and Yield of Cassava (Manihot esculenta Crantz) and some Soil Properties in Ibadan, Southwestern Nigeria

Maintenance of soil fertility status and optimum crop yield has been a great task in Nigeria. Against this background, studies were conducted in 1994 and 1995 growing seasons at the Teaching and Research Farm, University of Ibadan, Nigeria to evaluate the productivity of cassava and soil properties and dynamics under some tillage practices. Randomized block design with four replications was used and the tillage treatments were Heaping [HP], No-Till + Herbicide [NTH], Ridging [RG] and No-Till-Slash and Burn [NSB]. Results revealed that tillage practices had no significant effect on sprouting percentage in 1994 but in 1995, HP treatment was significantly (P < 0.05) higher than others. Tillage had no marked effect on cassava height in both years while number of leaves only differed significantly (P < 0.05) 8 months after planting with HP treatment being higher than others. Stem girth showed no marked differences among treatments in both years. Similarly, in both years, cassava fresh root yield and yield components were not significantly affected by tillage practices. NSB showed significantly higher soil bulk density at planting in both years than other treatments. Generally, soil chemical properties were not markedly affected by the tillage practices. The highest cost of production was observed under NSB while RG produced the highest returns. The study suggests that successful growing of cassava under reduced tillage practices is practicable in an Alfisol in this agro-ecological zone