blueberries

Protecting berries with sunflower extract

November 30, 2023 By EarthWise Leave a Comment

Many of us buy blueberries, raspberries, blackberries, and more in those little clear plastic clamshell boxes. We try to check them out at the store to make sure they are ok and even if are, many soon end up coated with gray mold and other fungi. It is a problem that is both disappointing and expensive.

Researchers from several Chinese Universities recently reported that compounds extracted from sunflower crop waste are quite effective at preventing rotting in blueberries. They suggest that the food industry could use these natural compounds to protect berries from postharvest diseases.

Sunflowers are grown globally for their seeds and oil. The flower stems themselves are generally considered to be a waste product. Sunflowers are known to be particularly resistant to many plant diseases so the researchers decided to investigate whether there might be chemical constituents within the plants that are responsible for the protective property.

Their research led to the isolation of 17 different compounds known as diterpenoids, including four that have never been identified before. They found that 4 of the compounds, including 2 of the newly discovered ones, were effective at preventing the growth of fungus on the blueberries.

Berries were wetted with the compounds and then dried off and injected with mold spores. Half of the treated berries were protected from the mold.

There is no reason that the method couldn’t be applied to a variety of crops. There is great appeal in the concept of using a harmless extract from a plant to render a food crop safe from fungal infestation. The technique holds great promise in preventing postharvest disease in fruit.

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Sunflower extract fights fungi to keep blueberries fresh

Photo, posted August 26, 2006, courtesy of Liz West via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Decline Of Pollinators Threatens Food Security | Earth Wise

August 24, 2020 By EarthWise Leave a Comment

Scientists have been sounding the alarm on the global struggle of pollinators for many years. According to a United Nations-sponsored report, 40% of invertebrate pollinator species, including bees and butterflies, are facing extinction. Approximately 80% of all flowering plant species, which are responsible for 35% of global food production, depend on pollination.

According to new research led by Rutgers University, crop yields for apples, blueberries, and cherries in the United States are being reduced by a lack of pollinators. The study, the most comprehensive of its kind to date, found that crop production would be increased if crop flowers received more pollination. In the U.S., the production of crops that depend on pollinators generates more than $50 billion a year.

For the study, which was recently published in the journal Proceedings of the Royal Society B, researchers collected data on insect pollination of crop flowers and yield of apples, highbush blueberries, sweet cherries, tart cherries, almonds, watermelons, and pumpkins at 131 farms across the United States and British Columbia, Canada. Four of those seven crops – apples, blueberries, sweet cherries, and tart cherries – showed evidence of being limited by pollination, meaning that their yields are lower than they would be with full pollination.

The researchers observed that honey bees and wild bees provided similar amounts of overall pollination, so managing habitat for native bee species or stocking more honey bees would boost pollination levels and, in turn, crop production.

Bees and other pollinators play a critical role in food production, and their continued decline could have devastating consequences.

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Decline of bees, other pollinators threatens US crop yields

Photo, posted April 22, 2012, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Melting Permafrost | Earth Wise

February 26, 2020 By EarthWise Leave a Comment

The Arctic is warming faster than any region on Earth and mostly we’ve been hearing about the rapid disappearance of Arctic sea ice. But the land in the Arctic is also undergoing major changes, especially to the permafrost that has been there for millennia.

Permafrost occurs in areas where the temperature of the ground remains below freezing for two years or more. About a quarter of the Northern Hemisphere’s landscape meets this criterion. Most of the world’s permafrost is found in northern Russia, Canada, Alaska, Iceland, and Scandinavia.

Permafrost regions previously carpeted in cranberries, blueberries, shrubs, sedges, and lichen are now being transformed into nothing but mud, silt, and peat. So-called regressive thaw slumps – essentially landslides – are creating large craters in the landscape. (The Batagaika Crater in the Yana River Basin of Siberia is a kilometer long and 100 meters deep).

Apart from the violence being done to the Arctic landscape, the greatest concern is that the permafrost has locked in huge stores of greenhouse gases, including methane, carbon dioxide, and nitrous oxide. It is estimated that the permafrost contains twice as much carbon as is currently contained in the atmosphere. As the permafrost thaws, these gases will be released. With them will be pathogens from bygone millennia whose impact cannot be predicted. Climatologists estimate that 40% of the permafrost could be gone by the end of the century.

As the permafrost thaws, the region’s ecosystems are changing, making it increasingly difficult for subsistence indigenous people and Arctic animals to find food. Landslides are causing stream flows to change, lakes to suddenly drain, seashores to collapse, and water chemistry to be altered.

The warming Arctic is about much more than disappearing sea ice.

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How Thawing Permafrost Is Beginning to Transform the Arctic

Photo, posted February 9, 2017, courtesy of the U.S. Geological Survey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wild Bee Loss Puts Crops At Risk

January 27, 2016 By WAMC WEB

Between 2008 and 2013, the United States lost nearly a quarter of its wild bees. Some 39% of our nation’s croplands rely on pollinators. Important farming regions – from California’s Central Valley to the Midwest’s Corn Belt – are among the areas grappling with wild bee declines.