Testing tomatoes for ultimate resilience

By Andi Anderson

In a unique experiment, researchers are testing the resilience of tomato plants by exposing them to stressful conditions that mimic those found in nature.

Entomology professor Esther Ngumbi is leading this study at her rooftop laboratory, where tomato plants are being deliberately flooded and subjected to insect herbivory. The goal is to understand how these plants respond to the combined stressors, which are increasingly common in farmers' fields due to climate change.

To simulate the effects of flooding, half of the tomato plants are submerged in bins of water. The plants, struggling under these conditions, show signs of stress, including yellowing leaves and wilting.

Some have even managed to produce flowers and small tomatoes despite the harsh environment. However, flooding is not the only challenge these plants face. Caterpillars, specifically the larvae of the tobacco hornworm (Manduca sexta), are feeding on the leaves, further weakening the plants.

The experiment is designed to compare the responses of stressed plants with those grown under normal conditions. Additionally, Professor Ngumbi’s team is investigating how soil microbes, particularly mycorrhizal fungi, affect the plants' ability to withstand these stressors.

The tomato plants are grown in soil from an Illinois farm, with half receiving an inoculation of mulch rich in mycorrhizal fungi. The team aims to discover whether this microbial inoculation improves the plants’ defense mechanisms against the caterpillars.

The researchers are also collecting samples of gases emitted by the plants, screening them for volatile organic compounds. These chemicals are part of the plants' natural defense system, helping to repel insects. By analyzing these emissions, the team hopes to gain insights into how the plants' defense systems are activated under stress.

This study is not just about understanding tomato plant resilience; it also provides valuable insights into how plants might cope with the increasing challenges posed by climate change.

The findings could inform future agricultural practices, helping farmers better manage crops in stressful environmental conditions.

Photo Credit: gettyimages-bastetamn