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This study was conducted to investigate the microbial enumeration and biomass of soil samples in the vicinity of dye pits in Zaria City, Northern Nigeria. A total of 90 soil samples were collected from five different dye sites with one location from non dye site. The pH of the non dye area was slightly acidic and ranged from 4.70-5.40 both in CaCl 2 and H 2 O while the contaminated samples ranged from 8.59-9.98 which indicate alkalinity. Microbial biomass carbon and nitrogen ranged from 170.82 -334.44 mg/kg, and 16.89 -37.28 mg/kg respectively. The soil microbial biomass, carbon and nitrogen including total bacterial and fungal counts of the soil samples were estimated using standard technique. Microbial enumeration showed the abundance of bacterial and fungal counts. The dominant genera of bacterial and fungal counts were Bacillus and Aspergillus. The highest bacterial count was observed in Kofar Gayan, while the lowest value was in Mabuga so also for fungal counts. Similar bacterial and fungal species were encountered in the different sampling locations in the course of this study, but their occurrences and levels of predominance were different. Bacillus spp dominated the bacterial isolates while Aspergillus spp was the most dominant Original Research Articlefungus across the different sampling locations. Bacterial and fungal abundance were typical of an environment with high species richness and functional diversity.

A pot experiment was conducted during winter season of (2013/2014) at Sakha Agricultural Research Station, Kafr El-Sheikh Governorate. The experiment aimed to investigate the effect of disodium ethylenediaminetetraacetic acid (EDTA) (0.0, 1.5, 3.0 and 4.5 mmol kg-1 soil), citric acid (CA) (0, 3, 6 and 9 mmol kg-1 soil) and humic acid (HA) (0.0, 0.2, 0.4 and 0.6 g kg-1 soil) on the phytoextraction of Cu, Zn and Pb from Al-Gabal Al-Asfar contaminated soil using indian mustard (Brassica juncea) and the leaching behavior of these metals from soil. The obtained results can be summarised in the following:-EDTA severely reduced indian mustard dry weight and visual symptoms of toxicity were observed, especially at 4.5 mmol EDTA kg-1 soil. Whilst, application of CA and HA ameliorated indian mustard growth.-EDTA was found to be the most efficient chelator in increasing concentrations of Cu and Zn in different indian mustard plant parts.-Increasing EDTA application rate up to 4.5 mmol kg-1 soil increased the concentrations of Cu by 1.91, 2.88, 3.04 and 1.56 folds and Zn by 1.43, 1.91, 1.83and 1.11 folds for roots, stem, leaves and seeds, respectively, compared to control treatment (0.0 mmol EDTA kg-1 soil).-Application of CA also increased Cu and Zn concentrations by different indian mustard plant parts, especially at 9 mmol kg-1 soil, but its efficacy was less than EDTA.-HA application increased Zn concentrations in different indian mustard plant parts with increasing its addition up to 0.6 g kg-1 soil, but its efficacy was less than that of EDTA and CA.-HA application did not affect Cu concentrations in indian mustard.-There were neither any perceptible concentrations of Pb in different plant parts of indian mustard except for roots clarifying that phytoextraction of Pb failed even after application of tested chelators.-Application of EDTA and CA to the soil increased the leaching of Cu, Zn and Pb under indian mustard cultivation with increasing application rate up to 4.5 and 9 mmol kg-1 soil, respectively. However, the effect of EDTA was many times higher than that of CA. Whilst, HA application did not affect the leaching of studied metals.-Using CA for the phytoremediation of Cu and CA and HA for the phytoremediation of Zn is favorable than EDTA despite the high efficiency of EDTA, due to the harmful effects of EDTA on plant growth and the increased risk of groundwater contamination via metal leaching.

The present investigation is one part of a research work on the agricultural and processing factors affecting the quality characteristics of processed tomato products specially juice and paste. This study concerned on the influence of fertilization rate of tomato crop with potassium humate on the quality characteristics of tomato fruits based on their chemical composition and functional compounds. A field experiment was conducted on tomato cultivar; (SV 8320 TD' F1 Hybrid) were treated with potassium humate at the levels of 25, 50 and 75 kg/Fed. Chemical analysis of the full ripe tomato fruits showed that fertilization with potassium humate slightly improved the fruit contents of total solids, total soluble solids sugars and ash while, total acidity, pH, protein and fat showed no changes. Moreover, the improving effect of fertilization was more pronounced on tomato contents of the functional compounds. It was found that vitamin C, total carotenoids, lycopene, βcarotene, flavonoids and phenolic compounds considerably increased due to fertilization with potassium humate. The improving effect was more pronounced at the high levels of potassium humate. The antioxidant activity of tomato fruits was also improved as a result of fertilization with potassium humate.