Biological Activity of Extract Solanum nigrum on some Biological Aspects of the Blue Fly Chrysomya albiceps (Diptera: Calliphoridae)

The current research evaluated the efficiency of alcoholic and alkaloid extracts of the leaves and fruits of the Solanum nigrum and investigated their effectiveness against the immature stages of the blue fly with 24-hour age at concentrations of 5, 10, 15, 20 mg/ml at the temperature of 30±1°C and relative humidity of 60±5%. It was revealed that the alcoholic extract of the fruits had the highest effect on killing the eggs of blue fly at all concentrations; accordingly, the death rates were estimated at 89.11% and 42.43% at the concentrations of 5 and 20 mg/ml, respectively, compared to that in the control, accounting for 9.27% mortality. It was also found that the alkaloid extract of the leaves of the plant outperformed in recording the highest rates of killing the eggs of blue fly, with death rates of 88.83% and 31.14% in the concentrations of 5 and 20 mg/ml, compared to the control group, amounting to 10.40%. Regarding the larval stages, the first stage was more sensitive than the other larval stages to all extracts of leaves and fruits of the plant. The highest mortality rates of the three larval stages were achieved by using the alcoholic extract of the fruits with the highest concentration of 20 mg/ml, compared to the alcoholic extract of the leaves; accordingly, the death rates of the third larval stage reached the highest rates of 57.11%, 68.20%, and 88.69% for the alcoholic extract of fruits and 53.19%, 68.64%, and 89.11% for that of leaves. The recorded data showed that the alkaloid extract of the S. nigrum leaves led to the highest mortality rates, compared to the alkaloid extract of the fruits, for all larval instars and at all concentrations. The mortality rates of the third larval stage with the highest concentration were 58.13% and 67.64%, respectively. The results of gas chromatography-mass spectrometry to investigate the chemical compounds in the alcoholic and alkaloid extracts of the leaves and fruits showed the presence of chemical compounds of varying numbers. The numbers of chemical compounds in the alcoholic extract of the leaves and fruits were 10 and 9, respectively, while it reached 17 and 23 for the alkaloid extract of the leaves and fruits of the plant, respectively.