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Mentha species are used in every day life in various food items. These species produce valuable secondary metabolites that scavenge toxic free radicals. Toxic free radicals can cause different diseases in the human body. In the present study free radical scavenging potential (1,1-diphenyl-2-picrylhydrazyl scavenging activity) in nine Mentha species were investigated to evaluate and explore new potential sources for natural antioxidants. The activity was performed after different time intervals with incubation period of 30 minutes. The methanolic extracts revealed that significantly higher activity (82%) was observed in Mentha suaveolens, followed by Mentha longifolia (79%), Mentha officinalis (76%) and Mentha piperita, Mentha pulegium, Mentha royleana (75%), respectively. Significantly same activity was observed in Mentha arvensis and Mentha spicata. Lower activity was observed in Mentha citrata (64%). The present study revealed that these species can be used as natural antioxidants.

In the present study the tolerance level of different fungi (Aspergil lus flavus, Aspergillus niger, Aspergillus versicolor, Scopulariop sis sp., Curvularia sp., Helminthosporium sp., Humicola grisea sp., Nannizzia sp., and Fusarium sp.) were investigated towards heavy metals which were isolated from contaminated peri-urban agricultural soils of Faisalabad.The concentration of heavy metals in soil is determined by using atomic absorption spectrophotometer. The degree of tolerance of fungi was measured by minimum inhibitory concentration in the presence of different concentrations of heavy metals (Cr and Pb) and compared to control sample. Tolerance analysis depicts that growth rate of fungal isolates decreased with increase in concentrations and few isolates are tolerant, some are moderately tolerant and some are sensitive towards metal concentrations of Cr and Pb. Most of the isolates were tolerant to metals. Among all tested fungal strains, few isolates of Aspergillus flavus and Aspergillus niger, Fusarium were tolerant to Cr and Pb. Thus these tolerant isolates can be used for the purpose of bioremediation in future.

The main objective of the review is to document, assess and analyze the results of the previously reported data on levels of different pesticides in selected fruits and vegetables from Pakistan. The findings of the previous studies clearly indicated that more than 50 % of the samples were contaminated with organophosphate, pyrethroids and organochlorine pesticides. Many studies reported that among fresh fruits and vegetables tomato, apple, melon, mango, grapes, and plum crossed the FAO/WHO permissible limits for these contaminants residual levels. The comparison of other regions showed that observed levels were found above maximum residue limits (MRLs) in 50 % of the samples but were in agreement with the studies from neighboring countries like China and Bangladesh. Higher hazard risk index (HRI) values were calculated for dieldrin, methamidophos, o,p′-DDT, diazinon and p,p′-DDT in apple, mango, banana, melon, potato and onion. The review also highlights that data on pesticide residues in foodstuff is scarce which should be overcome by further extending studies from different areas of Pakistan. In order to ascertain the provision of food suitable for human consumption, it is imperative to monitor pesticides in food commodities by the country's authorities and enforce guidelines based on permissible limits.

The gladiolus (Gladiolus spp.) industry is based on its flower and also its corm production.

No abstract

At the inception of Pakistan in 1947, there was practically no plant protection service in the country and economic soundness of plant protection measures was not even realized for a long time. The use of chemicals as preventive measures to reduce losses by insects and diseases was almost non-existent during 1960s. However, the “grow more” pressure rendered the traditional methods insufficient, to control the ever increasing pest problem from 1970s onwards. Consumption of pesticides in Pakistan has increased from 665 metric tonnes (MT) in 1980 (when subsidy was withdrawn) to 69897 MT in 2002. This colossal increase in pesticide consumption has not led necessarily to an increase in the yield of crops, as demonstrated by Poswal and Williamson (1998) and Ahmad and Poswal (2000). This indiscriminate use of pesticides has destroyed the bio-control agents in the agro-ecosystems and the populations of natural enemies of the insects and pests have declined up to 90 percent during the last decade (of the past century) especially, in cotton growing areas of the country [Hasnain (1999)].

Phytoremediation potential of L. minor for cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) from two different types of effluent in raw form was evaluated in a glass house experiment using hydroponic studies for a period of 31 days. Heavy metals concentration in water and plant sample was analyzed at 3, 10, 17, 24, and 31 day. Removal efficiency, metal uptake and bio-concentration factor were also calculated. Effluents were initially analyzed for physical, chemical and microbiological parameters and results indicated that municipal effluent (ME) was highly contaminated in terms of nutrient and organic load than sewage mixed industrial effluent (SMIE). Results confirmed the accumulation of heavy metals within plant and subsequent decrease in the effluents. Removal efficiency was greater than 80% for all metals and maximum removal was observed for nickel (99%) from SMIE. Accumulation and uptake of lead in dry biomass was significantly higher than other metals. Bio-concentration factors were less than 1000 and maximum BCFs were found for copper (558) and lead (523.1) indicated that plant is a moderate accumulator of both metals. Overall, L. minor showed better performance from SMIE and was more effective in extracting lead than other metals.