This research was carried out to determine the best phosphorus fertilizer for improvement of sweet potato phosphorus uptake, growth and yield. The phosphorus fertilizer sources used were organic (Pacesetter), single super phosphate and crystallizer while the sweet potato variety used was Shaba. The experiment was laid out in randomized complete block design (RCBD) with three replications. Sweet potato plants from plots treated with crystallizer fertilizer at the rate of 500kg/ha had the highest phosphorus uptake and vegetative growth while control plots produced plants with highest tuberous yield. It is, therefore, recommended that crystallizer applied at the rate of 500kg/ha be used for significant phosphorous uptake which equally leads to better quality sweet potato tuber and appreciable vegetative growth. It is also recommended that the soil phosphorus be maintained at low level around 6.80mg/kg for achievement of high tuberous yield in sweet potato.

The objective of this study was to evaluate the yield and quality of sweet potato under the influence inorganic fertilizer (NPK 15:15:15) at the recommended rate of 130kg/ha, organic fertilizer (Pace Setter) at the recommended rate of 3t/ha and organo-mineral fertilizer (combination of NPK 15:15:15 and Pacesetter organic fertilizer) at the rate of 1.5 t/ha. The fresh and dry weights of the samples were taken after which their proximate analyses were done to determine the levels of the quality determinants (moisture content, crude protein, ether extract, crude fibre, Vitamin A and ash content) in them. At the end of the experiment, harvesting was done to determine the yield per treatments as well as the quality parameters of the leaves and tubers. It was found that organic fertilizer could increase the quantity of ether extract, crude fibre and vitamin A contents of sweet potato tubers above other fertilizer treatments though organic fertilizer competed with the control in increasing the ash and crude protein contents of sweet potato tubers. However, inorganic fertilizer increased only energy content of the tubers above organic and organo-mineral fertilizer treatments. It is, therefore, concluded that organic fertilizer should be used to increase sweet potato tuber quantity and quality.

No abstract

A study was carried out to evaluate the effect of varying hormonal treatments and length of cuttings of clonal materials on the sprouting and rooting abilities of Jatropha curcas L. Two stem cutting lengths: 30cm and 60cm were pre-treated with two types of auxins: Naphthalene Acetic Acid (NAA) and Indole-3-Butyric Acid (IBA) at four concentration levels: 0 (control), 100, 150 and 200mgl -1 . The experiment was a factorial laid as randomized complete block design. Results showed that cutting length and hormone concentration had significant effect (P<0.05) on all parameters. The 60cm cuttings performed better than the 30cm cuttings in terms of sprouting, rooting and plant biomass accumulation. The untreated cuttings (control) showed better development than those treated with NAA and IBA. Significant interaction effects were observed between the cutting length and hormone concentration for all parameters (p<0.05). The 60cm cuttings performed better when untreated with hormone while 30cm cuttings performed best when treated with IBA at 200mgl -1 . Hence, 60 cm untreated cuttings could probably be used for large scale propagation of J. curcas while 30cm cuttings required hormonal treatment for high performance.

The present investigation was on the assessment of concentrations of different heavy metals in irrigation water