Residual Effects of Cassava Peel and Tithonia Compost on Growth, Yield and Nutrient Uptake of Lima Bean Varieties

Abstract

The application of compost in agricultural systems is widely acknowledged for its ability to enhance crop yields and improve soil nutrient status over time. This study examines the comparative performance of two Lima bean varieties (B17 and LB 52) under immediate and residual applications of composts made from cassava peel and Tithonia diversifolia, each mixed with Poultry manure in ratio 3:1 on a dry basis. Composts (Cassava Peel Compost (CPC) and Tithonia divesifolia compost (TdC) were applied at rates of 5 t ha-1 and 10 t ha-1, alongside a control (no compost) in a randomised complete block design (r = 4). Immediately after harvesting, residual trial was conducted to assess the residual impact of compost on lima yield. Data on Dry Matter (DM, g), Chlorophyll Content (CC, μg/gfw), post-soil nutrient and plant tissue analyses were collected and analysed using descriptive statistics and analysis of variance at α=0.05. The results showed that compost application significantly increased CC, DM, and Soil Nitrogen (SN, %) and Soil Potassium (SP, mg kg-1), with the highest responses observed in the LB 52 variety treated with TdC at 10 t ha-1. The CC and DM increased from 2.89 μg/gfw and 508.58 g to 2.96 μg/gfw and 557.58 g, respectively, across both trials. Similarly, SN and SP contents increased from 3.35% and 1.94 mg kg-1 to 3.47% and 2.13 mg kg-1 under 10 t ha-1 TdC. Overall, LB 52 produced higher yields than B17. Notably, the residual trial demonstrated improved crop performance and soil nutrient status, highlighting the sustained benefits of compost application over time.