Soil Characteristics, Microbial Compostion of Plot, Leaf Count and Sprout Studies of Cocoyam (<i>Colocasia</i> [Schott] and <i>Xanthosoma</i> [Schott], Araceae) Collected in Edo State, Southern Nigeria

Abstract

Cocoyam (Colocasia [Schott] and Xanthosoma [Schott]) belongs to the family Araceae and
Alismatales order. The aim of this study is to collect cocoyam from the eighteen Local
Government Areas (LGA) in Edo state and describe them based on leaf count and sprout
percentage. Using random stratified sampling methods, cocoyam were collected. Field trials were conducted in the Experimental Garden, Department of Plant Biology and Biotechnology. The soil was subjected to analysis at the Soil Science Department, University of Benin to determine its characteristics and suitability for the growth of these arable crops. The soil microbial count was 6.25 X 10⁵ and 1.34 X 10⁵ cfu/g for bacterial and fungi respectively Phosphorus, potassium, manganese and copper were low, zinc and iron were moderate whereas soluble salts were high in the soil. Results of percentage sprout indicate accessions from Esan south east had highest percentage sprout of 92.0 % while accessions from Owan East had the lowest percentage sprout value of 33.3 %. Visible sprouting was observed beginning from seventh day after planting. Leaf count reveals varied levels of significance at P ≥ 0.5 from March to July. Highest mean count of 1.35± 0.85 was obtained from Egor in March. In April, highest mean count of 5.42± 2.00 was obtained from Esan North East and 8.58 ± 1.69 as highest mean count in May was obtained from Ovia North East. Owan West had the highest mean count in June and July with 14.50±2.84 and 15.50± 1.76 respectively.  This study suggests great amount of cocoyam diversity. Their leaves is an important vegetable which may be available all year round. The cocoyam accessions can sprout with minimum requirements. More investigation is required to elucidate their constituents of these uncommon vegetable.