Asian Journal of Soil Science and Plant Nutrition

Aims: This study examined the dynamics of soil nutrients and nutritional quality of worowo (Senecio biafrae) using cow dung/sawdust compost enriched with neem meal.

Study Design: The experimental design was Randomized Complete Block Design (RCBD).

Place and Duration of Study: The study site was the Teaching and Research Farm of Ekiti State University, Ado-Ekiti, Nigeria, between March and October, in years 2020 and 2021.

Methodology: In two seasons, 20 cm worowo vines were planted in 8m² beds, with six treatments replicated four times. NPK 15-15-15 at 60 kg N/ha was contrasted with CDSNM (60 g N/kg) applied at 0, 10, 20, 30, and 40 t/ha. The organic treatments were applied at two weeks before planting, and NPK applied two weeks after planting. Soil’s attributes and nutritional contents of worowo were measured at 180 days after planting in the two seasons. Soil and vegetable sample were collected, prepared, and taken to the laboratory for analysis.

Results: Soil’s attributes were enhanced by the addition of CDSNM. The SOM, N, P and K quantities in the first season were 15.5 g/kg, 1.4 g/kg, 15.5 mg/kg and 0.5 cmol/kg, which increased to 19.5 g/kg, 2.7 g/kg, 24.4 mg/kg and 1.3 cmol/kg respectively, in the second season. Worowo’s quality improved by the addition of the organic source. Vines produced by CDSNM applied at 40 t/ha had higher Crude-fibre (CF), protein, moisture, ash, and mineral contents than NPK and the other treatments, at both seasons. The CF contents were in the order: 40 t/ha-12.00±0.59> NPK-11.20±0.59> 30 t/ha-11.00±0.59> 20 t/ha-10.62±0.59>Control-10.50±0.59> 10 t/ha-10.45±0.59, which followed the same order at the second season.

Conclusion: The organic-N-enriched compost positively impacted the soil and nutritional quality (CF in particular), of worowo vegetables. Application of 40 t/ha of CDSNM could therefore be adopted for optimal production of more nutritious worowo vines.