Shifting the balance of growth vs. defense boosts crop yield

December 17, 2019

Cold Spring Harbor Laboratory (CSHL) scientists are figuring out how to pack more kernels onto a corn cob. One way to boost the productivity of a plant, they say, is to redirect some of its resources away from maintaining an overprepared immune system and into enhanced seed production. Now, a team led by CSHL Professor David Jackson has found a gene that could help them tweak that balance.

To flourish in the wild, plants must be constantly on guard. With an unpredictable array of bacteria, fungi, and viruses lurking in the soil and air, a plant must maintain a robust immune system that is ready to counter any attack. This vigilance comes at a cost: Energy spent on pathogen defense cannot be used to grow taller or produce seeds. But the trade-off is crucial.

For crop plants, however, the situation is different. Corn growing in a farmer's carefully tended field faces fewer threats than the same plant might encounter on an untamed prairie. In this controlled environment, plants could probably ease up on their anti-pathogen protections--but getting them to do so will require some genetic tinkering.

"If we can convince the plants that they don't have to spend a lot of energy on defense, they can put more energy into making seeds," Jackson says.

In work reported in the Proceedings of the National Academy of Sciences, Jackson and his team have identified a gene in corn that contributes to both the plant's development and to the control of its immune system. Manipulating this gene, they say, could be a way to increase crop yields by reprogramming how a plant balances its investments in growth and defense.

Corn plants cannot survive without the gene, which is called Gß (pronounced GEE beta) and encodes part of an essential signaling complex. Seedlings engineered to lack Gß quickly turn brown and die, which postdoctoral fellows Qingyu Wu and Fang Xu determined was because the plant needs the gene to keep its immune system in check. Without it, an overactive immune system attacks the plant's own cells.

By experimenting with dozens of genetically diverse lines of corn, Wu and Xu found that within the right genetic context, plants can grow without Gß. By studying these plants, they discovered that Gß also impacts the size of a plant's meristems, reservoirs of stem cells from which new growth originates. What's more, the team linked naturally occurring variations in the Gß gene to the production of corn ears with unusually abundant kernels.

Jackson says his team's findings indicate not only that Gß is involved in both growth and immunity, but that it likely mediates crosstalk between the cellular pathways that control these competing functions. The researchers are already digging deeper into those interactions, with the hope that they will be key to developing higher-yield crops.
-end-


Cold Spring Harbor Laboratory

Related Immune System Articles from Brightsurf:

How the immune system remembers viruses
For a person to acquire immunity to a disease, T cells must develop into memory cells after contact with the pathogen.

How does the immune system develop in the first days of life?
Researchers highlight the anti-inflammatory response taking place after birth and designed to shield the newborn from infection.

Memory training for the immune system
The immune system will memorize the pathogen after an infection and can therefore react promptly after reinfection with the same pathogen.

Immune system may have another job -- combatting depression
An inflammatory autoimmune response within the central nervous system similar to one linked to neurodegenerative diseases such as multiple sclerosis (MS) has also been found in the spinal fluid of healthy people, according to a new Yale-led study comparing immune system cells in the spinal fluid of MS patients and healthy subjects.

COVID-19: Immune system derails
Contrary to what has been generally assumed so far, a severe course of COVID-19 does not solely result in a strong immune reaction - rather, the immune response is caught in a continuous loop of activation and inhibition.

Immune cell steroids help tumours suppress the immune system, offering new drug targets
Tumours found to evade the immune system by telling immune cells to produce immunosuppressive steroids.

Immune system -- Knocked off balance
Instead of protecting us, the immune system can sometimes go awry, as in the case of autoimmune diseases and allergies.

Too much salt weakens the immune system
A high-salt diet is not only bad for one's blood pressure, but also for the immune system.

Parkinson's and the immune system
Mutations in the Parkin gene are a common cause of hereditary forms of Parkinson's disease.

How an immune system regulator shifts the balance of immune cells
Researchers have provided new insight on the role of cyclic AMP (cAMP) in regulating the immune response.

Read More: Immune System News and Immune System Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.