Physico-chemical Properties in Rhizosphere of Some Field Crops at Different Growth Stages in a Sandy Clay Loam Soil in Sourthern Nigeria

The effects of different cultivated crops and their growth periods on some hydraulic and chemical properties of a sandy clay loam soil at the University of Port Harcourt, Teaching and Research Farm, in Choba, Rivers State, Nigeria was studied. The objective was to understand the changes in soil physical and chemical properties near the plant environment during the growing period for optimum management. Four (4) crops: Maize (Zea mays L.), Okra (Abelmoschus esculentus), Pepper (Capsicum annuum), and Garden egg (Solanum melongena F.) were planted to native fallowed soil and the soil properties measured at three (3) growth stages of the crops viz: Establishment, Flowering, and Maturity. Results revealed that the plants did not modify the soil textural class. Significant changes in bulk densities and saturated hydraulic conductivity were found during the flowering stage of the crops. Bulk density of 1.36 and 1.34 g cm-3 were significantly (p<0.05) low at during flowering and maturity stages, respectively, in Garden egg soils. The highest saturated hydraulic conductivity (Ksat) values of 22.9 and 27 cm h-1, respectively, were significant (p<0.05) during the same periods for garden egg, followed by Maize and Okra. Results also revealed that Okra, Pepper and Garden egg significantly (p<0.05) reduced the soil acidity at flowering growth period. Maize contributed significant additions of soil organic matter to the soil at flowering and maturity periods. Maximum removal of available plant nutrients was at flowering stage for maize when more than 80% of the plant had shown tasselling and cob formation. Therefore, monitoring the growth stages of specific plant could help in nutrient and soil management and changes in soil physical and chemical properties.