For Plants, More Stress Means Stronger Offspring

You would think that being under constant stress is a bad thing, but for plants, it comes with some added benefits, new research shows. Plant scientists at Lancaster University have found that plant parents, exposed to pesticides, disease or other stressors, can pass on their immunity to their seedlings, resulting in stronger offspring.

Researchers were intrigued by this inherited advantage considering the DNA sequence of the studied plants remained the same. The key lies in their genetic "memory," passed down from one generation to the next, and which tells plants how to cope with stressful conditions.

After three years of research, Lancaster scientists believe a more subtle process is at play, meaning that defensive genes "switched on" or "expressed" in the plant would then remain in a "primed" state, able to more rapidly respond to stress in their offspring.

This breakthrough could help scientists better understand how the mechanism could benefit farmers and growers.

"Once we have that level of detailed understanding of how this impacts upon plants it will open the door to different approaches to growing - methods which are less dependent on pesticides and potentially less harmful to the environment," Dr. Mike Roberts, a senior lecturer at the Lancaster Environment Centre, who led the study, said in a statement.

Species of plants respond differently to various environmental stressors, with some genes expressed "loudly" and others "quietly." Understanding the biology behind their responses is necessary if scientists want to implement new growing approaches.

"Different groups of hormones regulate how plants respond to different stresses and, sometimes, these responses can work against each other - for example, the way a plant protects itself against disease could actually make it more vulnerable to insect attack," Roberts explained.

"We will be exposing plants in our laboratories at Lancaster to a series of different stresses in different combinations and different generations to measure the effect on the plants," he added.

The findings were published in the journal Plant Physiology.