Researchers have discovered a new way to increase plant growth by suppressing the natural response to environmental stress. The scientists have found a modifier protein that can be used to interfere with the plant's growth repression proteins independently of the previously identified hormone Gibberellin. They believe this will lead to higher crop yields, even in unfavorable conditions.

When plants face difficult conditions, like drought or high soil salinity, they produce growth-regulating DELLA proteins. It is already known that Gibberlin can reverse the effects of DELLA proteins, but the research team, led by Durham University’s Dr Ari Sadanandom, discovered that the Small Ubiquitin-like Modifier (SUMO) protein also reduces the amount of growth repression experienced.

They demonstrated the ability to block the mechanism of control growth, GID1 receptors, when DELLAs were joined with the SUMO protein. The subsequent obstruction of GID1 by SUMO-paired DELLAs led to improved growth during stress. This was done independently of the much studied growth hormone Gibberellin, that plants use to break down DELLA proteins.

The study, which involved members from the University of Nottingham, Rothamsted Research and the University of Warwick, was conducted on Thale Cress, but the team believes the research could also be applied to commercial crops, such as barley, corn, rice and wheat. They researchers believe the interaction between the modifier protein and the repressor proteins can be modified in a number of ways, including using biotechnology techniques and through conventional plant breeding methods.

“What we have found is a molecular mechanism in plants which stabilizes the levels of specific proteins that restrict growth in changing environmental conditions,” says Dr Sadanandom. “This mechanism works independently of the Gibberellin hormone, meaning we can use this new understanding for a novel approach to encourage the plant to grow, even when under stress. If you are a farmer in the field then you don’t want your wheat to stop growing whenever it is faced with adverse conditions. If we can encourage the crops to keep growing, even when faced by adverse conditions, it could give us greater yields and lead to sustainable intensification of food production that we must achieve to meet the demands on the planet’s finite resources.”

The research was published in the journal Developmental Cell and was funded by the Biotechnology and Biological Sciences Research Council. It is the subject of pending patent applications and commercial rights are available from Plant Bioscience Limited, Durham’s commercialization partner for this technology.