September 4, 2019
According to legend, the ancient Romans, after defeating Carthage in a series of protracted wars, razed the enemy city to the ground and sowed the surrounding soil with salt as a final act of spite. Though such a deliberate act, if it happened at all, probably did not have the desired effect, rising soil salinity is an unfortunate bi-product of agricultural activity in some regions, one which has led to the devastation of agricultural land in various parts of the world. But researchers at Brigham Young University my have found a promising technique for reversing salt-damaged soil that could lead to a rejuvenation of previously damaged acreage.
BYU undergraduate Caitlyn McNary, one of six co-authors of a paper on the subject, explains the problem: “As an area of land is repeatedly used for farming, the salinity rises; the irrigation water has salt in it and when it evaporates or is taken up by the plants, the salt is left behind.” But this team of researchers, led by Brent Nielsen, professor of microbiology and molecular biology at BYU, has found that bacteria found in the roots of certain salt-tolerant plants can be used to successfully inoculate other plants against overly salty soil conditions.
“We take the roots of these salt-tolerant plants (called halophytes), grind them up and grow the bacteria in a petri dish in the lab,” Nielsen explains. “Doing this, we isolated over 40 different bacteria isolates, some of which can tolerate ocean-level salt content.”
Alfalfa seeds were then infused by the team with a solution containing the bacteria isolates, and then their ability to grow in high-saline conditions was tested and monitored. The results were indeed promising, as significant growth of the alfalfa was observed both in the lab and in greenhouse experiments. The research team has also conducted similar experiments on rice, green beans, and lettuce, with the next step being to conduct trials in the field.
As the project gets ready to move into the next phase, Nielsen expresses great optimism in the technique’s potential. “We’ve long wondered if increasingly salty land was just a losing battle or if there was something we could do about it,” he said. “Now we have shown there is something we can do about it.”
(Source: Science News)
