mold

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

Here Come The Lanternflies | Earth Wise

May 15, 2023 By EarthWise Leave a Comment

The spotted lanternfly is an invasive pest from Asia that primarily feeds on tree of heaven, which is itself an invasive species that has become widespread. The real problem is that the lanternfly can also feed on some 70 other plants such as grapevines, maples, fruit trees, and more.

The lanternfly was first discovered in the US in Pennsylvania in 2014 and has since spread to 14 states including New York, Massachusetts, Connecticut, and Rhode Island. (It was first spotted in New York in Staten Island in 2020 and has continued to spread).

The insect poses a significant threat to New York’s agricultural and forest health. Both the adults and nymphs feed on the sap of plants which stresses them making them vulnerable to diseases and other insect attacks. They also secrete a sticky substance that attracts molds and interferes with photosynthesis.

Lanternflies are not strong fliers. They mostly spread through human activity by laying their eggs on vehicles, firewood, outdoor furniture, and other objects that people transport.

The bout of unusually warm weather that the Northeast experienced in early spring is likely to have jumpstarted the spotted lanternfly timeline and hatching could be bumped up to as early as May.

Agriculture officials are asking for people to look for spotted lanternfly egg masses and scrape them off with implements with a sharp edge. Adult insects should be reported to local authorities and should be killed if at all possible. There is lots of information online about how to recognize the egg masses and the insects. Spotted lanternflies are not a direct threat to humans, but they have the potential to cause great harm to vineyards, orchards, and forests.

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Spotted Lanternfly

Photo, posted September 12, 2018, courtesy of the U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Bees And Plastic

July 17, 2019 By EarthWise Leave a Comment

Wild bees in Argentina have recently been found to be constructing nests entirely made of flimsy plastic material left on farms and scientists don’t know why.

In 2017 and 2018, researchers at Argentina’s National Agricultural Technology Institute built wooden, artificial nests for wild bees. These bee species burrow into nests to individually lay larvae rather than having a large hive with queens and workers. The artificial nests provide hollow openings that bees generally fill with cut leaves, twigs, and mud.

Sixty-three wooden nests were constructed and three were found lined entirely with plastic. The bees carefully cut bits of plastic in the shape and size of fingernails and arranged them in an overlapping pattern in their nests. The plastic seems to have come from plastic bags or films, which have a similar texture to the leaves bees ordinarily use to line their nests. And, in fact, leaves were readily available to the bees making use of plastic.

This is the first time that bees have been seen making nests entirely out of plastic, but for years scientists have known bees were incorporating plastic into their building materials. Research is needed to determine the potential impact plastic might have on bees, but the nest building shows that bees are highly adaptive to changing environments.

Plastic often forms a threat to wildlife in the form of microplastics that can be consumed. But there is no evidence that bees are consuming plastic. Some researchers have speculated that the plastic in bees’ nests may form a barrier against common nest issues like mold and parasites.

At this point, it is not clear whether it is a good thing or a bad thing that some bees are choosing plastic over natural materials, but it is certainly interesting.

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Wild bees are building their homes from plastic—and scientists aren’t sure why

Photo, posted December 12, 2014, courtesy of Judy Gallagher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Increasing Biological Invasions

June 1, 2017 By EarthWise

Invasive species have been a problem for quite some time. Over the years, we have grappled with – among other things – invasive plants from Japan, zebra mussels from eastern Europe, and Asian fungus that kills off ash trees in our forests.