Phyto-availability of Chromium to Fluted Pumpkin (Telfairi occidentalis Hook F) in an Ultisol

The greenhouse and field trials were carried out at the Faculty of Agriculture experimental site, University of Benin to determine the influence of Cr on some agronomic characters of Telfairia occidentalis, nutrient content and uptake and some chemical properties of the soil. Completely randomized and randomized complete block designs were used in greenhouse and field trials respectively. In the greenhouse trial, chromium nitrate (Cr (N03)2 ) was applied at rates of 0, 50, 100, 200 mg per 5 kg sieved and air-dried soil obtained from a depth of 0-15cm. The rates of 0, 20, 40 and 80 kgha-1 equivalent to pot rates were used in the field trial. Results showed that the soil used was texturally sandy loam and an ultisol as revealed by its low percentage base saturation.. The soil pH, organic carbon, effective cation exchange capacity, exchangeable acidity, N, K, Mg, Ca, Na, Fe, Mn and Zn content of the soil decreased inconsistently at various levels of Cr treatments. The organic carbon however increased in the field while the available P appreciated in the entire trials. The Cr content of the soil increased with the increased levels of Cr treatments throughout the trials. The N, P, K, Mg, Ca, Na, Fe, Mn and Zn content of shoot and root and their uptake also decreased consistently with increased Cr treatments. In addition, the Cr content as well as uptake by the shoot and root also increased consistently with increased rates of the Cr applied in the trials with the minimum levels of the Cr content and uptake recorded at the control treatments. The crude protein content decreased with increased Cr treatments in both root and shoot with the control having the highest crude protein content. The highest crude protein percentage was recorded in the shoot compared to the root. A decrease in the dry matter yield with increased Cr treatments in shoot and root was recorded in the trials. Results also showed that the Cr influenced the height, collar girth, leaf area and number of leaves with control treatments higher than other treatments at final harvest.