Preliminary studies on the activity of two photosensitizer compounds for sustainable control of aphid, <i>Rhopalosiphum padi</i> (Hemiptera: Aphididae) and its associated predator, <i>Chrysoperla carnea</i> (Neuroptera: Chryso

The aphid, Rhopalosiphum padi (L.), is considered a major pest of many crops and causes huge losses in crop production by feeding or transmitting viral diseases. Insecticides were used to control this pest, but the repeated use of pesticides has led to the emergence of resistance among insects, in addition to toxic effects on animals and humans and environmental pollution. Therefore, it was necessary to develop and introduce new and environmentally safe technology for controlling insect pest populations. The photosensitizers are promising new technologies in pest control; so, the study aimed at assessing the effectiveness of two photosensitizers, Magnesium Chlorophylline (Mg-Chl) and Copper Chlorophylline (Cu-Chl), against the adult aphid, R. padi and its biological control agent, Chrysoperla carnea. Four concentrations (10-2, 10-3, 10-4, and 10-5) of each compound under different exposure periods to light (0, 1, and 2 h) were evaluated on R. padi adults, and studied the effect of these compounds on its biological control agent, C. carnea. The findings showed that the mortality percentage reached 96.67% at the highest concentration of Mg-Chl (10-2), while it reached 86.67% at Cu-Chl (10-2) after ten days of treatment with 2 h of exposure to sunlight, but the compounds did not affect the natural enemy, C. carnea. Therefore, magnesium chlorophylline and copper chlorophylline could be included as part of an Integrated Pest Management (IPM) for aphid control.