Assessment of the Effect of Plant Density on Cassava Yield in Imo State

This study assesses the effect of varying plant population densities on root yield and quality of cassava in Imo State, South East Nigeria. Cassava is the most widely grown food crop in Imo State, providing food security and income for rural households. Plant density determines the degree of resource competition among plants and significantly affects tuber size distribution, total yield, and dry matter content. Despite the importance of this agronomic factor, empirical data on optimal plant density for the dominant cassava varieties in Imo State conditions are limited. This study establishes a randomised complete block design experiment at the National Root Crops Research Institute Umudike, testing four plant densities: 10,000, 12,500, 16,667, and 20,000 plants per hectare, using TMS 30572 variety. Fresh root yield, dry matter content, harvest index, and cyanide content are measured at 12 months after planting. Findings reveal that 10,000 plants per hectare produces the highest fresh root yield per plant but 12,500 plants per hectare maximises yield per unit land area at an average of 28.4 tonnes per hectare. Higher densities above 16,667 plants per hectare significantly reduce dry matter percentage and increase cyanide content beyond acceptable thresholds. The study concludes that 12,500 plants per hectare is the optimal density for TMS 30572 under Imo State conditions. It recommends this density as the standard planting recommendation for extension agents in South East Nigeria's cassava-producing communities.

Keywords: cassava, plant density, root yield, NRCRI, Imo State.