Growth responses of C3 and C4 crops to soil physico-chemical properties in Rivers State, Nigeria

This study evaluated the growth responses of C3 and C4 crops to soil physico-chemical properties in Rivers State. The C3 crop refers to Pumpkin and Cucumber while C4 crop refers to Amaranthus in this study. The research work made use of three crops (Pumpkin, Cucumber and Amaranthus in some selected sites in Rivers State and the study was carried out both in the dry and wet seasons. Soil samples were collected from both topsoil (0-15cm) and subsoil (15-30cm). The crops and soil samples were taken to the laboratory for further analysis. Mean values and standard deviations were used to describe the analysis while analysis of variance (ANOVA), Duncan, and Kruskal Wallis were used to test the hypotheses. All analyses were carried out using Statistical Package for Social Sciences (SPSS) 21.1 Version. Findings showed that sand content in Oyigbo had the highest in the topsoil at 95.37% while Etche had highest in silt content at 1.87%. For the subsoil, Oyigbo also had the highest sand content at 93.30% while Ikwerre had the highest clay content at 6.63% in subsoil. For chemical properties of soil, total organic carbon and magnesium were highest in Oyigbo at 1.91% and 24.00% respectively for topsoil while for subsoil potassium was highest in Ikwerre at 8.30%. It was also discovered C3 and C4 crops planted in Oyigbo, Etche and Ikwerre varied from the nutrients standards recommended by USDA (2014). The following nutrients and minerals were considered: energy, carbohydrates, protein, total fat, cholesterol, dietary fiber, vitamins, folates, niacin, pantogenic acid, pyridoxine, riboflavin, thiamin, Electrolytes, sodium, potassium, calcium, iron, magnesium, manganese phosphorus, and zinc. For standards recommended by (USDA 2014), only energy, iron, zinc, manganese, vitamin E, riboflavin, pyridoxine, niacin and pantothenic acid at Oyigbo met the standards, also Riboflavin and iron at Ikwerre met the (USDA 2014) standards while only folates at Etche met the (USDA 2014) standards. The study recommended that the soil nutrients and pH should be improved across the three locations and the acidic nature of both topsoil and subsoil should be improved by neutralizing the soil with lime.