Sobia Chohan

Influence of Frequently Used Chemical Insecticides on Mycoflora Carried by Common Housefly, Musca domestica L.

The housefly, Musca domestica L. (Diptera: Muscidae), is a major medical and veterinary insect pest. It serves as a vector of many pathogenic microorganisms causing spoilage of food and diseases in human and animals. Use of chemical insecticides is adapted as a principal tool to manage housefly. Insecticides have many unforeseen ecological consequences including effects on non-target organisms. In the present study, we have assessed the effects of 10 different synthetic insecticides on the growth of mycoflora associated with the external body of the housefly by using poison food technique. Our results reveled that all synthetic insecticides enhanced the growth. Surprisingly, in most of the cases, mycelial growth of fungi was significantly increased at high concentration as compared with lower concentration. This study provides useful information about the dangerous effects of synthetic insecticides on environment by increasing the spread of various non-target pathogenic, mycotoxigenic, and food spoiling fungi, carried by houseflies.

Chemical composition and antifungal potential of medicinal plants against seedborne mycoflora of eggplant (Solanum melongena L.)

Abstract Antifungal activities of medicinal plants were observed against seedborne mycoflora of eggplant (Solanum melongena). The effect of ethanolic leaf extracts of Mangifera indica, Mentha spicata, Citrus limon, Eucalyptus camaldulensis against four isolated fungal species including Fusarium oxysporum, Aspergillus flavus, Rhizopus stolonifer and Penicillium digitatum was evaluated at various concentrations, by using the poisoned food technique. The impact of the extracts on seed germination and growth of eggplant was assessed by seed treatment and growth in a greenhouse experiment. Total flavonoids of E. camaldulensis were analyzed through spectrophotometer, using quercetin as a standard. Physico-chemical parameters were also determined. Antifungal activity showed that maximum inhibition percentage of P. digitatum (67.78%) and F. oxysporum (64.44%) was observed at the highest concentration (80%) of C. limon and E. camaldulensis extracts, respectively, followed by M. spicata extract against A. fl avus (63.33%) and R. stolonifer (52.22%). Least inhibition percentage of F. oxysporum, P. digitatum, R. stolonifer and A. flavus was 6.67, 7.78, 14.44 and 16.67%, respectively, at the lowest (20%) concentration of M. spicata. The greenhouse experiment showed variations in seedling germination and post-germination growth. E. camaldulensis extract showed an increase in percent germination (78.98%) over untreated control (62.83%), root and shoot length and fresh and dry weight of root and shoot with the consequent reduction in disease symptoms. Phytochemical analysis depicted the presence of alkaloids, flavonoids, tannins, saponins in all extracts while steroids and glycosides were absent. A fair amount (10.38 mg QE g-1DF) of flavonoid was present in leaf extract of E. camaldulensis. Physico-chemical analysis showed pH of 4.6, ash content of 0.41% and weight loss on drying of 8.14%.