The effectiveness of agricultural wastes as bioremediation materials is gaining research attention as a better option in mitigating the issue of crude oil effects in soil environment. In the present study, the growth performance of Telfairia occidentalis and Arachis hypogaea linn in crude oil polluted soil amended with plantain peels (PP) and cocoa pod husks (CPH) were investigated. Eight kilograms (8 kg) each of dried soil samples were collected and weighed into 60 polythene bags. The polythene bags except the pristine control were polluted with 80 ml of crude oil and allowed for 14 days of soil acclimatization. The treatments comprising of CPH and PP were amended after 14 days, using the following concentrations: 0, 100, 150 and 200 g and allowed to acclimatize for 60 days. T. occidentalis and A. hypogaea linn were cultivated immediately after treatment regimen. The pH of the amended and un-amended soil samples were observed to be at a range recommended for effective bioremediation of hydrocarbon polluted soil. The organic carbon content of the CPH amended soils were significantly reduced as compared to the PP amended soil. The phosphorus, nitrogen, potassium and other essential soil parameters evaluated were significantly high (P<0.05) in CPH amended soil than the PP amended soil. Crops grown in the rehabilitated soils possess a high adaptability in CPH amended soil than the PP amended soil. The amendments most preferably cocoa pod husks which tend to be more effective in the reduction of hydrocarbon content of the soil should be utilized in the enhancement of microbial degradation of crude oil product in soils.

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The bioremediation potential of ten different treatments formed from two organic sources of nutrients: coconut husk ash (CHA) and pineapple peel (PP) on 5kg of soil polluted with 400ml of crude oil were monitored for 84 days. The changes in the physicochemical properties of the soil were observed, the degradation process was monitored by; the measure of the total petroleum hydrocarbon (TPH) loss, the total bacterial and fungal counts, the crude oil utilizing bacterial and fungal counts. The result revealed that there was a reduction in the soil TPH with all treatments and also the polluted control, which may be owing to natural attenuation. The treatment, PP12 was seen to have the lowest TPH value of 40.40 ± 0.40 mg/kg at the 84 th day with a percentage reduction of 89.90. This was followed by the PP8 (49.733±0.267mg/kg) and PP4 (70.000±0.577mg/kg), also the POC (polluted control) had a concentration of 245.333±1.453mg/kg at the 84 th day which is a 38.67% reduction. The treatment, CHA12 influenced the TPH to a concentration of 78.000±1.528mg/kg which was an 80% reduction. The total bacterial count had the highest CFU/g of 2.06 x 10 7 ± 0.006 on the soil treated with CHAPP12 and the least count was at POC (2.3 x 10 6 ± 0.007cfu/g). Crude oil utilizing bacteria were least with the POC (0.21 x 10 4 ± 0.010 CFU/g) and were more at the PP12 treated soil (1.3 x 10 5 ± 0.012). Some of the probable bacterial isolates identified through biochemical testing included Bacillus spp., Serratia spp., Proteus spp., Pseudomonas spp., Enterobacter spp., Klebsiella spp., Aeromonas spp.and Staphylococci spp. The fungi isolates ranged from 3.0 x 10 4 CFU/g to 6.0 x 10 4 CFU/g and identified fungi included Cephalosporiumspp, Coccidioides immitis, Aspergillus niger, Aspergillus fumigatus, Penicillium spp, Trichophyton mentagrophyte, and Moraxella spp.

Local accessions of African Yam Bean, a poorly studied and under-utilized but important food crop, from Abia, Akwa Ibom and Cross River states of Southern Nigeria were studied for variation in seed yield and pod characteristics. Correlations were carried out on the studied characters to determine the degree of mutual association among them while path coefficient analysis was used to partition the correlation coefficients into their direct and indirect effects on seed yield. Results revealed that significant differences (p<0.01) exist among the accessions with respect to the studied characters. Mean number of seeds per pod ranged from 13.27 to 18.87; seed weight per pod from 3.19 to 6.21g; weight of 100 seeds from 22.86 to 36.72g; pod length from 21.67 to 36.82 cm and pod width ranged from 0.79 to 1.05 cm. Number of seeds per pod and pod length had significant positive association with seed weight per pod. Pod width also correlated positively with seed weight in some accessions. Positive direct effects on seed weight per pod were obtained with number of seeds per pod and pod length. The results taken together revealed significant variations in the accessions and provide evidence for effective selection which is a prerequisite for genetic improvement.