IPM Chronicle

Modifying the genes of mosquitoes can transform these pests into a weapon capable of fighting disease. Zika, dengue and chikungunya are all viral diseases spread by the yellow fever mosquito, Aedes aegypti. Because there are no cures for these viruses, health officials are eager to find new methods to slow their spread. Genetically engineered mosquitoes are being studied as a tool for this reason.

The previous issue of the IPM Chronicle discussed the development of gene editing techniques to enhance crops. The discussion will now turn to a molecular technique that provides the ability to turn off (silence) genes within an organism’s cells. This process of silencing genes can be accomplished through a process called ribonucleic acid interference or RNAi.

Last fall, a crop of peppers was started in the greenhouse and there was a standing order for biological control agents to be delivered as part of our integrated pest management program. Everything was in place and there should not have been any problems, but then aphids were spotted in the pepper flowers.

Different options for control were considered. Sprays were quickly eliminated as an option since the peppers were going to be eaten and a spraying into the flowers would be difficult. If a biological control agent could be used, it was crucial to find out which aphid was the culprit. The aphid in question turned out to be the foxglove aphid, which is difficult to control biologically. In addition, we used two parasitoids that did not stop the foxglove aphid’s advances. Therefore, the options were limited to releasing the lady beetles.