This study focused on heavy metals (Lead (Pb), Zinc (Zn) and Cadmium (Cd)) contamination in the vegetable Corchorus olitorius (C.olitorius) leaves cultivated along a major road. Samples the vegetable, C. olitorius leaves) were collected from two sites, one of which is located on a major highway and the other remotely located from any form of industrial activity and which served as the control site. These samples were collected at distances of 10, 20 and 30m from the roadside and analyzed for Pb, Zn and Cd content by atomic absorption spectrophotometer. The mean concentration of heavy metals in the studied vegetable with effect to distance from the road was compared with the permissible values given by WHO/FAO. Mean concentration of heavy metal in C. olitorius leaves ranged from 0.013 to 0.310mg/kg, 2.500 to 4.850mg/kg and 0.063 to 0.205mg/kg at 10m, 20m and 30m distances respectively from the road. In all cases, it was observed that the closer the plants were to the road, the higher the heavy metal burden. The result of this study shows that, while the concentration of heavy metals in C. olitorius leaves from the control site remains constant, (i.e. showing no sign of contamination) the concentration of heavy metals in C. olitorius leaves cultivated along major road decreased with an increasing distance from the road. @JASEM

The objectives of this work were to investigate the effects of wheat straw constituents on total seed germination and on time needed for seed germination to start and to assess the usefulness of evaluating the recovery of germination to help guide the screening for a sequential search of bioactive natural phytochemicals. Dose-response bioassays of lettuce seed germination to increasing concentrations of six fractions of methanol-water extract were conducted and whenever inhibition of germination exceeded 90% non-germinated seeds were transferred to distilled water and recovery of germination investigated. Only the fractions essentially composed by neutral polar compounds and by acids failed to inhibit total germination. Fractions composed by strong acids, basic compounds and fatty acids plus steroids completely inhibited total germination at 5mg mL −1 , the former also inhibiting germination by more than 90% at 1mg mL −1 . In these three fractions the concentration necessary for 100% inhibition was estimated to range between 4.1 mg mL −1 and 4.4mg mL −1 . Time needed for germination to start was always significantly increased even by fractions that failed to affect total germination. Basic compounds were the most effective in delaying the start of germination increasing it more than 4-fold at 2mg mL −1 from 1.0 to 4.3 days. When non-germinated seeds were transferred to distilled water persistence of complete inhibition was only found with strong acids, almost full persistence with basic compounds. Thus the consideration of recovery of germination makes possible a more informed choice of the fraction to select for further bioassay guided search for phytochemical with herbicide activity. The fraction is the one composed by strong acids,

Garri, a pre-eminent staple diet in Nigeria, accounts for over 70% of the total calorie intake of more than 50% of Nigeria's population. This study investigated the fungal flora and the level of aflatoxin contamination of garri sold in two open markets (Uyo and Oron) in Akwa Ibom State, Nigeria. Samples randomly purchased from each market were aseptically transported to the laboratory and cultured for fungi. Identification of fungal cultures was done using morphology of the isolates. Three subsamples from each location were extracted, spotted and quantified for aflatoxins B1, B2, G1 and G2. Values were the means from 3 subsamples. Data were processed using T-test and means separated for statistical significance at P<0.05 using the Least Significant Difference (LSD). Fungi isolated from both markets were Fusarium verticolloides, Cercospora sp, Aspergillus flavus, A. niger and A. parasiticus. From the Uyo samples, the following additional fungi were found Fusarium solanii and A. parasiticus. Aflatoxin B1 (AFB1) was significantly higher (P<0.05) in samples from Oron (21.67 µg/kg) compared to Uyo (3.33 µg/kg). Aflatoxins B2, G1 and G2 were below detection limit in the samples. AFB1 in garri samples from these two markets in Akwa Ibom State is being reported, probably for the first time.

Pesticide residue constitutes a danger to soil micro and macro fauna and flora and to humans. This study assessed the impact of the application of Aspergillus niger as a pesticide remediating agent on Lambda-cyhalothrin and some of its associated heavy metals translocated to the leaves of Lactuca sativa. A Complete Randomized Design (CRD) experiment using three Treatments was conducted. Lambda-cyhalothrin was extracted from the Samples using the multiple residue technique and its residue determined using Gas Chromatography with Pulsed Flame Photometric Detector (PFPD). The associated heavy metals were determined using the Atomic Absorption Spectrophotometric method. Data so generated were means from five replicates, and were subjected to a one way analysis of variance-ANOVA with Tukey HSD Test for differences between means at 99% confidence interval (P≤0.01). The results show that the highest mean value of Lambda-cyhalotrhrin residue in L. sativa leaves was found in Treatment A (1.50 mg/kg), a value which was significantly higher (P≤0.01) than the residue found in Treatments B (1.0 mg/kg) and C(0.02 mg/kg). Mean Lambda-cyhalothrin residue in Treatment A alone was above the Maximum Residue Level (MRL) of 1.0 mg/kg in vegetable set in the legal EU regulation.The application of A. niger also precipitated a significant reduction (P≤0.01) in the level of all the heavy metals evaluated except Arsenic. All the heavy metals evaluated were however below the WHO/FAO safe limit. The result from this study posits A. niger as a promising mycoremediation agent of pesticide pollution.

ABSTRACT:The use of pesticide, although increases agricultural yield and improves public health is also fraught with a number of ecologic, agronomic and health concerns. This research investigated the impact of an ex-situ mycostimulation of one of the in-situ soil fungi on some agronomic characters and yield of Talinum fruticosum planted on a herbicide treated soil. Experimental site was laid out in a 3×8 Randomised Complete Block Design (RCBD). Amongst other fungal species found in the soil, Paecilomyces variotii was selected for multiplication and reintroduction to the field 96 hours after the application of glyphosate and 48 hours after the transfer of T. fruticosum from the nursery. Data on agronomic parameters were taken between the 1 -6 weeks after planting (WAP) while data on the biomass yield (kgha -1 ) was taken (on harvesting) at 6 WAP. Data were mean values from 8 replicates and analysed using the statistical package IBM SPSS version 20. Mean values were separated for statistical significance at 95% confidence interval, using the Least Significant Difference (LSD). The results showed that the Treatments had significant (P<0.05) effects on height of plants, density of plants, size of leaves and internode spacing at the different WAP as well as the biomass and yield of Talinum at 6 WAP. The results obtained from the present study thus further reaffirm the crucial role of fungi as nature's original recyclers. If properly managed and stimulated, fungi can contribute significantly to improving soil health, thus improving food security in a sustainable manner. © JASEM https://dx