A gene called AHL15 (AT-hook motif nuclear-localized protein 15) promotes longevity in annual flowering plants, according to a new study published in the journal Nature Plants.

“Plants have growing points on their stems. These are groups of stem cells that can form new stems with leaves or flowers,” said Professor Remko Offringa from the Institute of Biology Leiden at Leiden University, the Netherlands, and his colleagues.

“In perennial plants, a number of those growing points remain vegetative, so that after flowering the plant can continue to grow in the next season. In annual plants, this does not happen and the plant dies.”

“We discovered a gene that determines whether growing points of a plant will remain vegetative after flowering.”

For the study, Professor Offringa and co-authors used Arabidopsis thaliana, a rapidly growing flowering plant native to Europe, Asia and northern parts of Africa.

“We overexpressed the AHL15 gene in Arabidopsis so that it is much more active than normal,” they explained.

“As with perennial plants, in the modified Arabidopsis plants some growing points remain in the vegetative phase.”

“The plants continue to grow after flowering and can blossom several times.”

When the researchers disabled the AHL15 gene, they noticed that the plants had a shorter lifespan.

“The discovery of the gene contributes to fundamental knowledge about plant life history and aging,” Professor Offringa said.

“The gene may also provide answers to the question of why during evolution certain species have become annuals and others have become perennial.”

“Many food crops, like rice and wheat, are annuals. Keeping some growing points vegetative in such a crop would allow the plants to continue to grow after harvesting. This may allow for several harvests from the same crop and thus to increase the yield per plant.”

“Farmers also have to plough less often when they grow plants that bloom more often. As a result, the soil biome will remain intact, which fits well with sustainable production in agriculture.”

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O. Karami et al. A suppressor of axillary meristem maturation promotes longevity in flowering plants. Nat. Plants, published online April 13, 2020; doi: 10.1038/s41477-020-0637-z