Student Research Spotlight - Kirsten Pearsons

Posted: May 13, 2016

This is the 7th of thirteen short news articles written by students, during the professional development class, about each other's research.

Decomposers – the Custodians of the Field

Under the surface of a dense cornfield, there is a whole society of creepy crawlies eating away dead plant tissues, breaking them down into pieces. They work very hard to keep the dead plant tissues from piling up, and facilitate the recycling of materials. However, the pesticides we use could be potentially harmful to this process, endangering the whole agro-ecosystem.

“It is really amazing how 90% of plants in the field are ultimately consumed by those creepy crawlies, also known as detritivores” said Kirsten Pearsons, a first year PhD student at Penn State University, supervised by Dr. John Tooker. “A healthy decomposer community pretty means healthy soil, healthy plants, and a happy farmer.” she said. However, these detritivores are likely to be damaged by the pesticides that are applied to many crops.

Pearsons is thus evaluating the impact of pesticides on detritivore community.  However, she is also evaluating the health of predators in these systems, since many of the detritivores are also predator’s food. “Pesticides could affect predators indirectly, because predators feed on decomposers in the field” she says. By transferring through food chain, the indirect effects of pesticides might decrease predator populations and further affect the pest community, which is controlled by predators.

“The inconspicuous relationship between pests and detritivores is linked by the predators. Fully understanding the relationships between pesticides, decomposers, predators, and pest populations, may allow us to develop novel strategies to control damaging pests" she said.