Discovery could lead to drought-resistant alfalfa
By Top Crop Manager
Jan. 4, 2016 - A recent study of plant genetics indicates that alfalfa, a forage crop used primarily for livestock, could be made more drought-resistant, which would reduce costs for producers and benefit the environment.
Agriculture and Agri-Food Canada (AAFC) research scientist Dr. Abdelali Hannoufa, who specializes in functional genomics and metabolic engineering, has discovered a gene in the alfalfa plant that regulates its capacity to maintain water content.
"The gene reduces water loss, so that the plant maintains its water content and can resist drought for a longer period of time," he says.
The gene in question is called microRNA156.
Hannoufa studies crop genetics at AAFC's London Research and Development Centre in Ontario. Collaborating with industry partners, he is finding ways to improve alfalfa through genomics.
"The gene (microRNA156) reduces water loss, so that the plant maintains its water content and can resist drought for a longer period of time," says Hannoufa.
MicroRNA156 "is a master gene regulator," he adds. "It functions by regulating a network of other genes, called down-stream genes, which control yield, stress tolerance and other factors."
The gene's function is being studied closely and the findings are applied to plants grown under controlled conditions in the Centre's state-of-the-art greenhouse facility.
Industry partners are also adapting this technology for use in field trials.
Results show that the gene also increases alfalfa's root length. Longer roots allow the plant to reach deeper into the soil to absorb water and can lock in nutrients, such as nitrogen. Enhanced nitrogen fixation can reduce the need for subsequent fertilizer applications.
Drought resistance is an important trait because it maintains a crop's viability through unpredictable climate conditions and increases its adaptability to grow in various soil types. Combined, these benefits translate into savings for the producer.
Alfalfa is also cost-efficient because it is a perennial crop. "You don't have to seed it every year," he notes.
In addition to being a valuable forage crop, "alfalfa is also being looked at as a crop for land reclamation," he says. Alfalfa's adaptability to less-than-ideal growing conditions means it can help restore soil that has been degraded through prolonged use, or at sites of oil and gas explorations.
Seeded over approximately five million hectares across Canada, Hannoufa says alfalfa is one of Canada's most important crops, but its full potential has yet to be realized because "it is being contemplated as a competitive, low-input bioenergy crop."
Ongoing research of gene functions, including that of other major crops like canola, may lead to further discoveries that enhance crop quality and performance under less-than-ideal production conditions.