A lawsuit filed in California claims the automaker’s philanthropic arm stole technology intended to help poor farmers, but it is not clear to what end.
The Upper Colorado River on the Grand Canyon last month. About 40 million people and 5.5 million acres of cropland depend on the Colorado for drinking water and irrigation.
In the mountain villages of Guatemala’s Western Highlands, farmers are combining ancient Maya knowledge with modern sustainable farming techniques to protect their crops from pests and disease. Smallholders are creating homemade biopesticides using plants with strong smells and flavors to deter pests on their family plots. This is helping to cut back on the use of increasingly expensive agrochemicals, many of which have been labeled as dangerous to human health and linked to soil degradation. About 60 Guatemalan communities in the Western Highland departments of Sololá and Huehuetenango, as well as Chiquimula in the east, are working to revive these traditional techniques with support from the international development organization World Neighbors. Their focus is to restore and strengthen traditional knowledge, combining it with agroecological practices that help families produce surplus food they can sell to boost household incomes. “Traditional farming techniques are becoming popular because they are simple practices to apply, use local resources, and have proven to be effective,” Dayani Roche, a program associate at World Neighbors, told Mongabay via email. Rather than a single ancient recipe, farmers are using “a living combination of ancestral knowledge, local experimentation and more recent agroecological practices,” he said, which are “safer for families, soil, water and biodiversity than many chemical alternatives.” The Maya civilization, which once stretched across modern-day Central America, had a rich history of farming dating back to 2000 B.C.E. Its most celebrated agriculture system is the milpa, a form of intercropping that involves a mix of maize, beans and…This article was originally published on Mongabay
A newly identified pest is raising concerns for North Carolina’s blueberry industry. What began as a mystery beneath North Carolina’s blueberry fields has now been traced to a surprising culprit: a giant root-feeding beetle never before confirmed attacking blueberries anywhere else in the United States. Researchers at North Carolina State University have identified the insect [...]
Brown rot is a common fungal disease in the Southeastern United States that affects stone fruits like peaches, cherries, and plums. Monilinia fructicola is a tan, fuzzy fungus that grows on tree flowers, twigs, and fruit, and is the most common cause of brown rot. Once brown rot infects a tree, the damage is irreversible, causing significant crop losses in commercial orchards. Farmers try to control the spread of M. fructicola by applying chemical sprays, called fungicides, to fruit trees in the spring.
In M. fructicola, a biosynthesis gene named MfCYP51 encodes a major protein critical to the fungi’s survival. Certain fungicides, called demethylation inhibitor (DMI) fungicides, stop M. fructicola from growing by targeting this protein. Over the last 20 years, DMI fungicides have become less effective against brown rot as M. fructicola becomes more resistant.
Living microorganisms and their metabolites can control fungal diseases as an alternative to chemical fungicides, known as biofungicides. Many bacteria produce compounds like hydrogen cyanide and pyrrolnitrin that damage fungal cells. However, scientists have not found a biofungicide suitable for commercial production. A group of researchers at Clemson University in the USA and Huazhong Agricultural University in China set out to test whether the soil bacteria Pseudomonas chlororaphis and Bacillus subtilis could be effective biofungicides against brown rot.
The researchers performed an incubation experiment to analyze how the fungal cells make their critical protein from the MfCYP51gene, a process called gene expression, under different fungicide treatments. They used 3 M. fructicola strains sensitive to traditional DMI fungicides and 3 resistant strains. They tested these with 5 different fungicide treatments: a DMI fungicide, a mixture of P. chlororaphis metabolites, a mixture of living B. subtilis cells, a DMI fungicide + P. chlororaphis metabolites, and a DMI fungicide + B. subtilis cells. They also set up a control treatment with sterile water instead of fungicide.
After 6 hours, the researchers extracted the molecule that measures gene expression, called RNA, from the fungi. They found that both the P. chlororaphis treatment and the DMI fungicide + P. chlororaphis treatment substantially reduced MfCYP51 expression in both the sensitive and resistant isolates compared to the controls. In contrast, the DMI fungicide, B. subtilis, and DMI fungicide + B. subtilis treatments increased MfCYP51 expression in the resistant isolates. The researchers concluded that P. chlororaphis has a unique ability to reduce gene expression, unlike other biofungicides.
To further investigate how the biofungicide treatments work, the team tested whether P. chlororaphis and B. subtilis produced the anti-fungal metabolite pyrrolnitrin. They added 1 milliliter of each treatment to a machine that separates and identifies liquid compounds using high pressure, called a high-performance liquid chromatograph. They found that the P. chlororaphis treatment contained pyrrolnitrin, so they hypothesized that it was responsible for reducing gene expression.
Additionally, the researchers tested their 5 treatments on brown rot in fruit. For each treatment, they took 10 Gala apples, washed and sterilized their surfaces, and sprayed them with the fungicides. After 24 hours, they poked holes in the apples with toothpicks and added 20 microliters of liquid containing M. fructicola cells to the poked holes. They placed the apples in a humid chamber for 5 days and measured the number and size of brown rot spots that developed on their surfaces.
Despite decreasing MfCYP51 expression, the researchers found that P. chlororaphis treatment alone didn’t reduce brown rot disease compared to the control, but the DMI fungicide and B. subtilis treatments did. The mixed treatments of DMI fungicide + P. chlororaphis and DMI fungicide + B. subtilis both reduced brown rot disease compared to the control, but only the DMI fungicide + P. chlororaphis treatment prevented it.
The researchers concluded that although biofungicides may not be fully effective on their own, commercializing them could allow farmers to use less DMI fungicide. They explained that scaling back the use of DMI fungicides would slow M. fructicola resistance. Finally, they proposed that future researchers test biofungicide mixtures containing pyrrolnitrin in the field to observe real-world effects on stone fruit trees.
The finding effectively paves the way for continued use of atrazine, a widely used herbicide that has been linked to birth defects and cancer in humans.
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