Rare-earth Lanthanides Make Crops More UV Resistant and Help Strengthen Photosynthesis
Lanthanides are a class of rare earth elements that are added to fertilizer as micronutrients to stimulate plant growth. But little is known about how they are absorbed by plants or influence photosynthesis, potentially leaving their benefits untapped.
Now, researchers from MIT have shed light on how lanthanides move through and operate within plants. These insights could help farmers optimize their use to grow some of the world’s most popular crops.
Published in the Journal of the American Chemical Society, the study shows that a single nanoscale dose of lanthanides applied to seeds can make some of the world’s most common crops more resilient to UV stress. The researchers also uncovered the chemical processes by which lanthanides interact with the chlorophyll pigments that drive photosynthesis, showing that different lanthanide elements strengthen chlorophyll by replacing the magnesium at its center.
Certain lanthanides are used as contrast agents in MRI and for applications including light-emitting diodes, solar cells, and lasers. Over the last 50 years, lanthanides have become increasingly used in agriculture to enhance crop yields, with China alone applying lanthanide-based fertilizers to nearly 4 million hectares of land each year.
Recent studies have shown that low concentrations of lanthanides can promote plant growth, root elongation, hormone synthesis, and stress tolerance, but that higher doses can cause harm to plants. Striking the right balance has been hard because of our lack of understanding around how lanthanides are absorbed by plants or how they interact with root soil.
For the study, the researchers leveraged seed coating and treatment technologies they previously developed to investigate the way the plant pigment chlorophyll interacts with lanthanides, both inside and outside of plants. Chlorophyll drives photosynthesis, but the pigments lose their ability to efficiently absorb light when the magnesium ion at their core is removed. The researchers discovered that lanthanides can fill that void, helping chlorophyll pigments partially recover some of their optical properties in a process known as re-greening.
“We found that lanthanides can boost several parameters of plant health,” said researcher Benedetto Marelli. “They mostly accumulate in the roots, but a small amount also makes its way to the leaves, and some of the new chlorophyll molecules made in leaves have lanthanides incorporated in their structure.”
This study also offers the first experimental evidence that lanthanides can increase plant resilience to UV stress, something the researchers say was completely unexpected.
“Chlorophylls are very sensitive pigments,” said researcher Giorgio Rizzo. “They can convert light to energy in plants, but when they are isolated from the cell structure, they rapidly hydrolyze and degrade. However, in the form with lanthanides at their center, they are pretty stable, even after extracting them from plant cells.”
Using different spectroscopic techniques, the researchers found that the benefits held across a range of staple crops, including chickpea, barley, corn, and soybeans. They also found that larger lanthanide elements like lanthanum were more effective at strengthening chlorophyll pigments than smaller ones. Lanthanum is considered a low-value byproduct of rare-earths mining, and it can become a burden to the rare-earth element supply chain due to the need to separate it from more desirable rare earths. Increasing the demand for lanthanum could diversify the economics of rare-earth elements and improve the stability of their supply chain.
Bacteria Form Protective Biofilms on Dust Particles
New research shows that living bacteria can survive on the surface of dust particles carried by desert storms over thousands of miles.
As a follow-up to a previous study in which they showed that species of Firmicutes, including Bacillus, are active players in dust storms, researchers have discovered that these bacteria can form microscopic biofilms over dust particles. These protective structures shield the bacteria from desiccation, extreme radiation and severe nutrient scarcity during their atmospheric journey.
The research, published in Communications Earth and Environment, contributes to the growing field of atmospheric microbiology. This discipline explores the survival and activity of microorganisms while in the atmosphere, sometimes over thousands of miles, and their impact on global cycles, ecosystems and human health. These processes significantly impact disease patterns, atmospheric CO₂ levels, plant diseases and even antibiotic resistance dispersal.
“Characterizing metabolically active, living bacterial communities is reshaping our understanding of microbiome-environment interactions,” explained researcher Naama Lang-Yona. “Our research suggests that the air we breathe contains entire bacterial communities from distant regions, bringing innovative traits that can integrate into local ecosystems, and potentially affect humans.”
In this study, the researchers successfully isolated and cultured bacteria brought in by dust storms under atmospheric conditions, focusing on beneficial Bacillus strains known for their positive applications in agriculture, construction and medical probiotics.
The team believes that natural selection during dust storms favors more innovative bacterial strains — a phenomenon that could potentially enhance their practical applications. This study also expands the traditional soil microbiome concept to include airborne microbial communities, broadening the known repertoire of survival strategies among these remarkable organisms.
Repeat Annual Biochar Use Amplifies Its Positive Effects
Farming produces a huge amount of crop waste, including straw, husks and stalks every growing season. Unfortunately, common disposal methods — burning, plowing the waste back into the fields, using it as animal feed, and even composting — release greenhouse gases.
In contrast, biochar — a charcoal-like material made by heating agricultural waste in low-oxygen conditions (pyrolysis) — offers a promising and eco-friendly alternative. New research shows that biochar can deliver lasting benefits for food security and climate mitigation when applied to farmland over the long term. In particular, the study showed that repeated annual applications not only sustain but also amplify biochar’s positive effects on crop yield, soil health, and greenhouse gas reduction.
The researchers analyzed high-quality field experiment records from 438 studies, including consecutive annual data from 29 long-term field experiments. The results, published in PNAS, demonstrate that annual biochar application over four years or more increased global crop yields by an average of 10.8 percent, cut CH4 emissions by 13.5 percent and N2O emissions by 21.4 percent, and raised soil organic carbon content by 52.5 percent.
While single application of biochar showed weakened effects over time due to the aging effect, the study showed it was still beneficial, with continued yields and soil organic carbon rise, and continued CH4 and N2O mitigation, though with a weakening trend.
| FDA Proposes Lowering Standard for Orange Juice — Because American Oranges Are Less Sweet than They Were 60 Years Ago On August 8, 2025, the US Food and Drug Administration (FDA) and USDA announced a proposed update to the standard of identity for pasteurized orange juice. The proposal will lower the minimum Brix (sugar level) of pasteurized orange juice from its current value of 10.5 to 10.0. This will “better reflect the natural Brix level of American oranges,” FDA said in its press release. But 60 years ago, the natural Brix of American oranges was 11.8, well above the minimum of 10.5. This lowering of the Brix standard is in response to a petition from the Florida orange juice processing industry. According to USDA, the average Brix of the Florida orange crop in 2023 was only 9.27. In order to meet the current standard, processors have had to rely on increasing percentages of orange juice imported from other countries, whose oranges have higher Brix values than Florida’s crop. “This America First action will end a 60-year-old rule that hurts domestic farmers and forces reliance on foreign imports,” the FDA said. The proposed rule is open for comments until November 4, 2025. What eco-ag farmers should be wondering is — what’s wrong with American oranges? Why has their sugar content dropped so significantly in the past 60 years? The processor petition lays the blame on citrus greening disease, which has devastated Florida citrus production since it first appeared in 2005. There is no cure for citrus greening, which causes trees to produce lower yields of lopsided, bitter fruit and eventually die. The Brix decline coincides with the spread of citrus greening, with the average Brix dropping below the FDA standard of 10.5 in 2017 and continuing to drop ever since. Since 2020, it’s consistently been below even the new proposed standard of 10 — a fact not mentioned in the FDA press release. The proposed standards accept this decline in quality as inevitable and irreversible. But, as Benny McLean explains in a recent interview with John Kempf, published in the May 2025 issue of Acres U.S.A., the effects of citrus greening have been greatly exacerbated by changes in citrus production practices over the past few decades. Increased herbicide use in orchards, abandonment of leguminous cover crops like hairy indigo, lack of genetic diversity, and closer tree spacing in orchards have all made commercial citrus trees weaker and more susceptible to diseases like citrus greening. What none of the official press releases about the proposed standard change mention is that, if Florida citrus growers were to seriously work on improving the health of their orchards using organic and regenerative practices, it might be possible to again produce oranges as sweet as those grown in 1963. Instead, they’re lowering the standard to say that sickly, bland, slightly bitter oranges are the new normal. But probably no one will notice — the FDA assures us that “this change is unlikely to affect the taste of pasteurized orange juice.” Like articles like this? Acres U.S.A. contributing editor Anneliese Abbott publishes weekly stories with eco-ag implications on our website: members.acresusa.com. |
