Earth Wise

A look at our changing environment.

You are here: Home / Archives for seeds

seeds

Elephants And Global Warming | Earth Wise

By Leave a Comment

A study by researchers at Saint Louis University has found that elephants play a key role in creating forests that store large amounts of atmospheric carbon and in maintaining the biodiversity of forests in Africa.  Since elephants are endangered, their status represents a significant threat to an ecosystem that is very important to the Earth’s climate.

The African rainforest contains trees with both low carbon density (light wood) and high carbon density (heavy wood).  High carbon density trees grow more slowly and can be crowded out by the faster growing low carbon density trees rising above them.  Elephants affect the relative abundance of these trees by feeding more on the low carbon density trees which are more palatable and nutritious.  This thinning of the forest allows the trees that sequester the most carbon to flourish.

Elephants are also excellent dispersers of the seeds of high carbon density trees.  Essentially, elephants are the gardeners of the forest.  They plant the forest with high carbon density trees and get rid of the weeds – in this case, the low carbon density trees.  According to the study, if elephants were to become extinct, the African rainforest – the second largest on earth – would gradually lose between six and nine percent of its ability to capture atmospheric carbon.

Elephants have been hunted by humans for millennia.   Gaining support for protecting them has mostly been driven by the argument that everybody loves elephants.  Focusing on their role in maintaining forest diversity has not driven much more action.  The hope is that the evidence of how important elephants are for climate mitigation will be taken seriously by policy makers to generate the support needed for improved elephant conservation.

**********

Web Links

Can Elephants Save the Planet?

Photo, posted March 15, 2008, courtesy of Michelle Gadd/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Perennial Rice | Earth Wise

By Leave a Comment

People have been cultivating rice for more than 9,000 years.  Cultivated rice is an annual crop which is often extended to two crops a year by a process called ratooning, which is cutting back annual rice to obtain a second, weaker harvest.

An extensive project involving multiple institutions in China, the U.S., and Australia has been developing perennial rice.  The researchers developed it through hybridization, crossing a type of Asian domesticated annual rice with a wild perennial rice from Africa.  Using modern genetic tools to identify candidate plants, the team identified a promising hybrid in 2007, planted large-scale field experiments in 2016, and released the first commercial perennial rice variety, called PR23, in 2018.

The researchers spent five years studying the performance of the perennial rice alongside annual rice on farms in China’s Yunnan Province.  For the most part, the yield of the perennial rice was equivalent to that of annual rice over a period of four years. 

Because farmers don’t have to plant rice each season, growing perennial rice requires almost 60% less labor and saves nearly half the costs of seed, fertilizer, and other inputs.

Perennial rice is already changing the lives of more than 55,000 smallholder farmers in southern China and Uganda.  The economic benefits vary by location, but overall profit increases ranged from 17% to 161% over annual rice.

There are already three perennial rice varieties available to farmers, but researchers aren’t done refining the crop.  They plan to use their methodology to enhance traits such as aroma, disease resistance, and drought tolerance to newer versions.

**********

Web Links

Farmers in China, Uganda move to high-yielding, cost-saving perennial rice

Photo, posted February 25, 2002, courtesy of Matthieu Lelievre via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Miracle Tree | Earth Wise

By Leave a Comment

The world needs to be fed without destroying the environment.   We need to grow more trees to store more carbon on earth and reduce the amount in the atmosphere.  But meanwhile, we decimate rainforests to produce palm oil and grow soybeans.

A startup company in California called Terviva thinks they have a solution.  It’s called pongamia, which is an ordinary looking tropical tree.  It produces beans packed with protein and oil, much like soybeans.  However, it has the potential to produce much more nutrition per acre than soybeans and it is hardy enough to grow on pretty much any kind of land without the use of pesticides, fertilizers, or irrigation.  In short, it is a miracle crop for a hot and hungry planet that is running out of fertile farmland and fresh water.

Pongamia is not a new or rare tree.  It is common in India but grows all over the world.  It is often planted as an ornamental here in the U.S.

The initial idea for making use of the hardy tree was to use its oil as a biofuel.  The seeds of pongamia are known to have a bitter taste and disagreeable odor, which is why the seeds or oil were never used for human or animal feed.  However, Terviva has developed a way to de-bitter pongamia oil.  Once this is done, it becomes a golden-colored substitute for olive oil. It also has enormous potential as a protein for plant-based milks and meats, since it contains all nine essential amino acids.

Terviva has raised more than $100 million to further develop pongamia and is now partnering with Danone, a $25 billion multinational food company, to develop pongamia as a climate-friendly, climate-resilient, non-GMO alternative to soy and palm oil.

***********

Web Links

This super-tree could help feed the world and fight climate change

Photo, posted December 15, 2015, courtesy of Lauren Gutierrez via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tepary Beans | Earth Wise

By Leave a Comment

Tepary beans are an ancient crop native to the northern part of Mexico and the southwestern part of the U.S..  They have been grown in those places by native peoples since pre-Columbian times.  They are still grown in Native American reservations in Arizona’s Sonoran Desert.  One can purchase them from some small farms in that region. 

What sets tepary beans apart from other beans is that they are among the most drought- and heat-tolerant legume crops in the world.  They can be grown without irrigation under conditions that are not viable for other crops.  They can be consumed by people like many other kinds of beans, and they can also provide forage for livestock with better nutrition content than many other plants.  They seem to be a very attractive option for a crop in the changing climate.  What is lacking, at present, is large supplies of tepary seeds to be planted.

Researchers at Texas A&M have been funded to bring tepary beans into modern cropping systems and diets.  The goal is to develop tepary bean cultivars with high biomass and yield that are still well-suited to drought and heat conditions.  Getting the beans to the point of widespread commercialization will take several years.  The end result should be of interest to pulse growers, seed industries, and food companies across the U.S.

Tepary beans are higher in fiber and protein than most other beans.  They come in several different colors, each of which has unique flavor and texture characteristics.  The white ones have a naturally sweet flavor.   The brown beans are slightly nutty in flavor and are similar to pinto beans.  If the Texas program is successful, we may all be eating tepary beans some day.

**********

Web Links

Tepary Beans Offer Producers A Low-Input, Climate-Resilient Legume Alternative

Photo, posted August 25, 2017, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Managing Pests With Cover Crops | Earth Wise

By Leave a Comment

The use of pesticides in global agriculture brings with it many problems including the killing of non-target, beneficial species as well as reversing pest-management gains from the use of conservation agriculture methods.

In a newly published study by researchers at Penn State University, the use of plant cover, such as cover crops, was shown to potentially be more effective at reducing pest density and crop damage than the application of insecticides without the downsides.  Cover crops reduce insect pest outbreaks by increasing pest predator abundance.

Cover crops are plantings that are primarily used to slow erosion, improve soil health, enhance water availability, smother weeds, and help control pests and diseases.  Typical cover crops include mustard, alfalfa, rye, clovers, buckwheat, and winter peas.  Most cover crops are fairly inexpensive to plant.

Plant cover can provide habitat for populations of natural enemies of pests.  Winter cover crops can harbor pest predator populations outside of the growing season of the cash crop.  When the cover crop is killed off to allow the growth of the cash crop, residues of the cover crop remain on the soil during the growing season, so they still enhance the habitat for pest predators.

Conservation agriculture includes methods like cover crops, no-till planting, and crop rotation.  The use of cover crops constitutes a form of preventive pest management that is an alternative to planting seeds treated with systemic insecticides to control early-season pests.  There is also the possibility for integrated pest managements, which is an approach in which insecticides are applied but only when pest numbers exceed economic thresholds despite the use of nonchemical tactics.

**********

Web Links

Cover crops more effective than insecticides for managing pests, study suggests

Photo, posted August 8, 2011, courtesy of USDA NRCS Montana via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Large Mammals And Climate Change | Earth Wise         

By Leave a Comment

The natural world has an important part to play in mitigating the effects of climate change.  We mostly think about the role of plant life which absorbs carbon in trees, grasses, and other flora.  However, a new study published by Oxford University looks at the role of large wild animals in restoring ecosystems and reducing the effects of climate change.

According to the study, there are three important ways in which large animals such as elephants, rhinos, giraffes, whales, bison, and moose can potentially mitigate the effects of climate change:  carbon stocks, albedo, and fire regimes.

When large herbivores graze, they disperse seeds, clear vegetation, and fertilize soil.  All of these things build more complex and resilient ecosystems which helps to maintain and increase carbon stocks in the soil and in plant tissues thereby helping to reduce CO2 in the atmosphere.

Grazing large animals trample vegetation which opens up areas of dense vegetation to create open mixes of grass and shrubs and can reveal snow-covered ground in cold regions.  Such open habitats are lighter in color (higher in albedo) and reflect more solar radiation into the atmosphere, cooling the Earth’s surface rather than heating it up.

Large grazing animals can lessen wildfire risk by browsing on woody vegetation that would otherwise fuel the fires and also by creating paths that act as firebreaks.

In marine ecosystems, whales and other large animals fertilize phytoplankton, which capture some 37 billion tons of CO2 each year.

Overall, large animals are an important part of the natural world’s ability to reduce the effects of the changing climate by helping with localized adaptation to the changes taking place in ecosystems.

**********

Web Links

Large mammals can help climate change mitigation and adaptation

Photo, posted August 20, 2017, courtesy of Jon Niola via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tourism And Invasive Species | Earth Wise

By Leave a Comment

Tourism has experienced exponential growth during the past 70 years.  In 1950, there were 25 million international tourist arrivals.  By 1990, it had ballooned to 435 million.  Between 1990 and 2018, the numbers more than tripled reaching more than 1.4 billion.  And by 2030, the number of international tourist arrivals is expected to reach 1.8 billion.

Tourism is vital to the success of many economies around the world.  Tourism can boost revenue, provide jobs, develop infrastructure, protect wildlife, and help preserve heritage sites and cultures.  But there can also be many downsides to tourism, one of which is that it can contribute to the introduction and spread of invasive species.  Non-native organisms can cause all sorts of social, environmental, and economic damage.   

Tourists help spread invasive organisms far and wide.  These organisms hitch rides in their luggage and on their shoes and clothing.  A 2011 study in New Zealand found that for every gram of soil on the shoes of in-bound international passengers, there were 2.5 plant seeds, 41 roundworms, 0.004 insects and mites, and many microorganisms. 

A new study by researchers from the University of Melbourne in Australia and AgResearch New Zealand examined to what degree tourism plays a role in the spread of invasive species.  According to the study, which was recently published in the journal NeoBiota, the research team found that the number of nights spent in hotels significantly correlated to the incursion of invasive species during that period.

Creating effective mechanisms to prevent the introduction of invasive species in the first place is the best way to prevent this problem. 

**********

Unwelcome guests: International tourism and travel can be a pathway for introducing invasive species

Number of tourist arrivals

Photo, posted March 27, 2005, courtesy of John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Disease in Cavendish Bananas | Earth Wise

By Leave a Comment

Cavendish bananas account for about half of global banana production and the vast majority of bananas entering international trade.  The plant is unable to reproduce sexually and instead is propagated via identical clones.  So, the genetic diversity of the Cavendish banana is exceedingly low. 

In 2008, Cavendish cultivars in Sumatra and Malaysia started to be attacked by Panama disease, a wilting disease caused by a fungus.  In 2019, Panama disease was discovered on banana farms in the coastal Caribbean region, its first occurrence in the Americas.  In the 1950s, Panama disease wiped out the Gros Michel banana, the commercial predecessor of the Cavendish.

Scientists at the University of Cambridge have found a novel way to combine two species of grass-like plants – which include bananas, rice, and wheat – using embryonic tissue from their seeds.  The technique allows beneficial characteristics, such as disease resistance, to be added to the plants.

Joining the shoot of one plant to the root of another to grow as one plant is known as grafting.  It was thought to be impossible to do with grass-like plants – called monocotyledonous  grasses – because they lack a certain tissue type in their stems.  But the new research, published in the journal Nature, showed it can be done with the plants in their earliest embryonic stages.

Cavendish bananas are sterile, so disease resistance can’t be bred into future generations.  But the grafting technique may provide a way to produce Cavendish banana plants that are resistant to Panama disease.  It may be possible to save an important food crop before it is too late.

**********

Web Links

New grafting technique could combat the disease threatening Cavendish bananas

Photo, posted July 1, 2015, courtesy of Augustus Binu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Benefits Of No-Till Farming | Earth Wise

By Leave a Comment

No-till farming is not new.  In fact, it was used as far back as 10,000 years ago.  But during the 18th and 19th centuries, tilling became popular because it allowed farmers to plant seeds more efficiently.

Tilling (or ploughing) is the process of preparing the soil for the cultivation of seeds by overturning the soil.  The practice works animal manure, weeds, and other surface residues deep into the soil.  While this all sounds like a good thing, it’s not. 

Tilling removes plant matter and loosens the soil, leaving the soil bare and vulnerable to erosion.  Tilling also displaces the millions of microbes and insects that form healthy soil biology.  The long-term use of tilling can turn healthy soils into lifeless growing mediums dependent on chemical inputs.  

But no-till farming also tends to rely on chemical inputs like glyphosate for weed control.  According to a new study recently published in Agronomy Journal, researchers at Penn State have found that farmers using no-till farming can reduce herbicide use and still maintain crop yields by implementing integrated weed-management methods.   

The research team conducted a nine-year experiment using herbicide-reduction practices in a crop rotation, which included soybean, corn, alfalfa, and canola.  Some of the practices used to reduce herbicide inputs included seeding small-grain companion crops with perennials, and plowing once in six years to terminate the perennial forage rather than killing it with an herbicide. 

While there was more weed biomass in the reduced herbicide treatment, the researchers found that the added weed pressure did not substantially affect crop yields. 

It is possible to make agriculture more environmentally-friendly and sustainable without sacrificing productivity.

**********

Web Links

No-till production farmers can cut herbicide use, control weeds, protect profits

Photo, posted February 11, 2019, courtesy of the United Soybean Board via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Seeds And Climate Change | Earth Wise

By Leave a Comment

Farmers and agricultural communities around the world are on the frontlines of climate change.  They are among the first to feel the impacts of hotter temperatures as well as more frequent and intense droughts and precipitation. These challenges pose a massive threat to both farmer livelihoods and global food security.

As the planet continues to heat up, many arid regions that already have marginal conditions for agriculture will be increasingly under stress. As a result, researchers from the Massachusetts Institute of Technology and the King Mohammed VI Polytechnic University in Morocco are working on a promising new way to protect seeds from this stress during their crucial germination phase. Their simple and inexpensive process, which was recently described in a paper published in the journal Nature Food, also provides plants with extra nutrition at the same.

The research team has developed a two layer coating for seeds designed for tackling issues related to drought. Drawing inspiration from natural coatings that occur on some seeds like chia seeds, the first layer is designed to protect the seeds from drying out. It provides a gel-like coating that grips any moisture that comes along and surrounds the seed with it.  The second (inner) layer of the coating contains preserved microorganisms called rhizobacteria, as well as some nutrients to help the seeds grow. 

The materials for the coatings are biodegradable, readily-available, and often used in the food industry already.  According to researchers, early tests using common beans have demonstrated encouraging results in Morocco, and more field tests of the seeds are currently underway.

As the climate continues to change, more innovations like this will be necessary for global food security.

**********

Web Links

Engineering seeds to resist drought

Photo, posted September 17, 2010, courtesy of Stacy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Blue Carbon Credits | Earth Wise

By Leave a Comment

Carbon credits have been around since the late 1990s.  The idea is to offset carbon emissions from some carbon emitting activity – anything from a wedding in California to a factory operating in Minnesota – by buying carbon credits earned from a carbon-absorbing activity, such as planting trees in the Amazon.

Blue carbon credits are credits earned by increasing the carbon stored in coastal and marine ecosystems. Coastal ecosystems such as mangroves, tidal marshes, and seagrass meadows in fact sequester and store more carbon per unit area than terrestrial forests and are increasingly being recognized for their important role in mitigating climate change. 

Blue carbon credit awards have to date been relatively few and far between and have mostly been granted for mangrove restoration efforts.  But mangrove projects are now ramping up dramatically in scope.  Scientists are working hard to analyze the amount of carbon in other ecosystem types – seagrasses, salt marshes, seaweeds, and seafloor sediments – so that these systems can also enter the carbon credit market.

Over the past 20 years, conservation scientists have spread over 70 million seeds in the bays of Virginia to restore over 9,000 acres of seagrass meadows that were devastated by disease in the 1930s.  The restored meadows are absorbing nearly half a ton of CO2 per acre. 

The rules to allow for blue carbon credits are recent and evolving, which is a big deal. The market may currently be small, but it is growing exponentially.  But as important as carbon credits are, it is still paramount to decarbonize before turning to offsets for existing emissions.

**********

Web Links

Why the Market for ‘Blue Carbon’ Credits May Be Poised to Take Off

Photo, posted July 2, 2009, courtesy of Nicolas Raymond via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Corn Belt Is Losing Topsoil | Earth Wise

By 2 Comments

According to a new study published in the Proceedings of the National Academy of Sciences, more than a third of the farmland in the U.S. Corn Belt has completely lost its carbon-rich topsoil due to erosion.   The affected area is nearly 100 million acres and the amount of carbon loss is nearly 2 million tons.

The study, led by scientists at the University of Massachusetts, Amherst, found that the greatest loss of carbon-rich topsoil was on hilltops and ridgelines.  This indicates that tillage – the repeated plowing of fields – was the primary cause of the erosion because loosened soils move downslope.

The loss of topsoil has reduced corn and soybean yields in the Midwest by 6%, resulting in a loss of nearly $3 billion a year for farmers.  In addition, the loosening of the topsoil increases runoff of sediment and nutrients into nearly waterways, worsening water quality.

Previous studies have shown that no-till farming practices can have a significant impact on reducing erosion.  A study published last November found that if farmers shifted entirely to no-till practices, it would reduce soil erosion from U.S. agricultural fields by more than 70%, as well as significantly reducing nutrient and sediment runoff. 

No-till farming is the practice of planting crops without tilling the soil.  Instead, seeds are planted through the remains of previous crops by planters or drills that cut seed furrows, place the seeds, and close the furrow.  Currently less than 15% of farmland in the upper Mississippi River watershed is farmed with no-till practices. 

Even partial changes in tilling practices could produce positive results for topsoil retention and for waterways.

**********

Web Links

One-Third of Farmland in the U.S. Corn Belt Has Lost Its Topsoil

Photo, posted September 15, 2010, courtesy of the United Soybean Board / Soybean Checkoff via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Restoring Coastal Ecosystems | Earth Wise

By Leave a Comment

Research published by CSIRO, Australia’s national science agency, examined the positive effects of restoration efforts for coastal ecosystems in terms of biodiversity, local economies, and human wellbeing.

Coastal ecosystems include saltmarshes, mangroves, seagrasses, oyster reefs, kelp beds, and coral reefs.  All of these have suffered declines of up to 85% over recent decades.  The research identified a number of successful coastal and marine restoration projects in recent years that indicate the likelihood that such efforts could be expanded by as much as a factor of ten to support human health and wellbeing, boost the adaptation response to climate change, and generate jobs. 

Some of the successful efforts identified included projects in the Great Barrier Reef to harvest coral larvae to boost large-scale coral restoration efforts.   Simple changes to how saltmarshes are planted have resulted in doubled survivorship and biomass.  In the U.S., the propagation of seagrass seeds has resulted in seagrass meadows recovering in areas where they had been lost decades ago.  In Indonesia, recovery of reefs impacted by blast fishing has been achieved by placing rocks or other hard structures underwater to help with coral colonization.

Investing in coral restoration creates jobs and can be used as a strategy to boost economic recovery and coastal marine health.  Restoration of marine habitats like kelp forests and oyster reefs has improved commercial and recreational fishing.

The United Nations has recognized the importance of coastal restoration and has declared the Decade on Ecosystem Restoration to start from 2021.

**********

Web Links

Scientists shine light on ‘bright spots’ to restore coastal ecosystems

Photo, posted November 29, 2012, courtesy of Robert Linsdell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Search For Lingering Ash | Earth Wise

By Leave a Comment

Ash trees are some of the most important plants along riverbanks and in wetlands.  There are three ash species in North America:  the white, green, and black ash.  Unfortunately, all three species are critically endangered because of the emerald ash borer.

The emerald ash borer is an exotic beetle from Asia that first showed up in the U.S. in southeastern Michigan in the summer of 2002.  The adult beetles do little damage but the larvae feed on the inner bark of ash trees and disrupt the tree’s ability to transport water and nutrients.  The beetles are now found in 35 states and 5 Canadian provinces and have killed hundreds of millions of ash trees.

The greatest hope for preserving ash tree species relates to lingering ash, which are those rare trees that have managed to survive the onslaught of the emerald ash borer. The idea is that those trees have some natural genetic resistance to the borer.  Getting seeds and cuttings from lingering ash and propagating them at nurseries may be the only way to get ash trees back into the natural landscape.

Lingering ash are extremely rare and therefore very hard to find.  As a result, researchers are reaching out to the public to help with the search and report the presence of these surviving trees in woodlands.

Researchers want to find large, mature trees left among those that were killed by the invasive insect and therefore display great resilience.  In Kentucky, university and Division of Forestry researchers are making use of software tools to engage the assistance of the public. An app called TreeSnap allows people to provide data on trees that they find in their community, on their property, or out in the wild.

**********

Web Links

Researchers Ask Public for Help Finding Lingering Ash Trees

Help Our Nation’s Trees!

Photo, posted May 31, 2014, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Restoring Seagrass In Virginia | Earth Wise

By Leave a Comment

Seagrass is found in shallow waters in many parts of the world.  They are plants with roots, stems, and leaves, and produce flowers and seeds.  They can form dense underwater meadows that constitute some of the most productive ecosystems in the world.  Seagrasses provide shelter and food to a diverse community of animals including tiny invertebrates, fish, crabs, turtles, marine mammals and birds.

In the late 1920s, a pathogen began killing seagrasses off the coast of Virginia.  In 1933, a hurricane finished them off completely.  For nearly 70 years thereafter, the bay bottoms of the Virginia coast were muddy and barren, essentially devoid of fish, shellfish, mollusks and other creatures that inhabit seagrass meadows.  The local scallop industry was no more.

The largest seagrass restoration project ever attempted has changed all that.  During the past 21 years, scientists and volunteers have spread more than 70 million eelgrass seeds within four previously barren seaside lagoons.  This has spurred a natural propagation of meadows that have so for grown to almost 9,000 acres, the largest eelgrass habitat between North Carolina and Long Island Sound.

The long-term research conducted by the team from the University of Virginia shows that the success of the seagrass restoration project is improving water quality, substantially increasing the abundance of fish and shellfish in the bays, and capturing carbon from the water and atmosphere and storing it in the extensive root systems of the grasses and in the sediment below. 

The study shows that marine restorations are possible on scales that contribute directly to human well-being.

**********

Web Links

Some Good News: Seagrass Restored to Eastern Shore Bays is Flourishing

Photo, posted May 17, 2019, courtesy of Virginia Sea Grant via Flickr. Photo credit: Aileen Devlin | Virginia Sea Grant.

Earth Wise is a production of WAMC Northeast Public Radio.

Has Wheat Changed for the Worse? | Earth Wise

By Leave a Comment

In recent years, the number of people affected by celiac disease, wheat allergies, or gluten or wheat sensitivity has increased dramatically.  Why this should be is not well understood.  One theory is that modern wheat varieties contain more immunoreactive protein than those used in the past.  Researchers at two German research institutions investigated this issue in detail. 

Wheat grains contain about 70% starch.  Proteins constitute 10 to 12% of wheat, and nearly 80% of that protein is gluten.  Gluten is a compound mixture of two types of protein subgroups:  gliadins and glutenins.

The researchers investigated the protein content of 60 preferred wheat varieties in use during the period between 1891 and 2010, making use of an extensive seed archive.  They selected 5 leading wheat varieties for each decade over that 120-year period and cultivated the plants under the same geographical and climate conditions.

The results were that the modern wheat varieties actually contain slightly less protein than old ones.  Gluten content itself has been essentially constant over the 120 years, although the proportion of gliadins (which are the prime suspect for causing undesired immune responses) was actually 18% lower while the proportion of glutenins was 25% higher.

Overall, they found no evidence that the immunoreactive potential of wheat has changed over the years as a result of the cultivation factors.

The researchers note that some of the other, less significant proteins in wheat have not been investigated with regard to their physiological effects, so there is more work to be done.  But so far, the culprit for increasing wheat sensitivity has not been found.

**********

Web Links

Is modern wheat off the hook?

Photo, posted July 3, 2009, courtesy of Clare Black via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Birdseed And Weeds | Earth Wise

By Leave a Comment

More than 55 million adult Americans feed wild birds and along the way spend more than three billion dollars a year on bird food as well as nearly a billion on bird feeders, bird baths, bird houses and other bird feeding accessories.  Feeding birds is a very popular hobby in both the United States and the United Kingdom.

Researchers at the University of Missouri in Columbia Missouri investigated the content of 98 commercially available bird feed mixes.  They uncovered several significant things.

The various mixes contained seeds from 29 weed species and almost all of the mixes contained seeds for pigweed, which can be a significant threat to agriculture.  One in ten of the mixes contained Palmer amaranth or waterhemp seeds that demonstrated a resistance to glyphosphate.   Other common weed species found in many of the mixes were kochia, common ragweed, foxtail species, and wild buckweed.

The overall collection of seed mixes contained an average of 363 amaranthus seeds in each kilogram of bird feed.  Based on this, it is possible that 105 million amaranthus seeds are transported in bird feed mixes each year.

According to the researchers, it is difficult to estimate the exact role that commercial bird seed plays in spreading troublesome weed species into new regions, but it is clear that the widespread use of these seed mixes is a contributing factor to the spread of weeds.

The researchers recommend careful weed management in crop fields designated for bird feed, as well as sieving during packaging to reduce weed seed contamination.  They also noted that regulatory measures adopted in Europe to limit weed seed content in bird seed have proven to be effective.

**********

Web Links

Examination of commercially available bird feed for weed seed contaminants

Photo, posted August 18, 2013, courtesy of Emma Craig via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bird Migration And Climate Change | Earth Wise

By Leave a Comment

A new study of bird migration shows the migration patterns are shifting as a result of climate change.   Researchers at Colorado State University, the University of Massachusetts, and the Cornell Lab of Ornithology, looked at the impacts of climate change on a continental scale.

The team looked at the nocturnal migratory behaviors of hundreds of species representing billions of birds using radar and other data.  They found that spring migrants are likely to pass certain stops earlier now than they would have 20 years ago.  Temperature and migration timing are closely aligned and the greatest changes in migration timing are occurring in regions warming most rapidly.  During the fall, shifts in migration were less apparent.

Migratory birds play an important role in ecosystems.  They consume insects, disperse seeds, and perform various other significant functions. Birds serve as critical metrics of the health of ecosystems.

Bird migration is a global phenomenon that can provide unique visibility into changes in the climate.  The ability to look at it on a global scale has only recently become practical as a result of big data technology and cloud computing.  The team was able to crunch the numbers for the study in 48 hours, a task that previously would have taken over a year of continuous computing.

The findings have implications for understanding future patterns of bird migration because birds depend on food and other resources as they travel.  As the climate changes, the timing of blooming vegetation or the emergence of insects may end up out of sync with the passage of migratory birds.  This could have negative consequences for the health of migratory birds.

**********

Web Links

Bird migration timing skewed by climate, new research finds

Photo, posted November 5, 2019, courtesy of Jerry Kirkhart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Canola Crops From Frost

By Leave a Comment

Canola is one of Canada’s most valuable crops.  In fact, Canada is the world’s largest exporter of canola oil.  The international market for canola oil is $27 billion a year.  The oil is very popular because it has a relatively low amount of saturated fat, a substantial amount of monosaturated fat, and is very neutral tasting.

Canadian canola farmers worry a great deal about late season, non-lethal frosts because the frosts prevent chlorophyll – a photosynthetic pigment in the seeds – from breaking down, a process they call “degreening”.  The farmers seek to have high-quality yellow embryos at seed maturity.  When the harvest contains more than 2% of green seeds, it can no longer produce Grade No. 1 quality oil.  When green seeds are processed to extract canola oil, the chlorophyll in the seeds reduces the oil’s storability and quality.  As a result, farmers receive a lower price for frost-damaged green seed canola.  This costs Canadian farmers and estimated $150 million annually.

Researchers at the University of Calgary have developed gene-based technology to produce canola plants that can withstand late-season frost and still produce high-quality seed.  They identified a specific protein that controls chlorophyll breakdown and seed maturity.  Genetic manipulation is able to enhance the seed degreening system.  They were able to reduce the amount of chlorophyll in the genetically modified canola lines by 60% after the plants were exposed to non-lethal frost. 

Ultimately, the researchers plan to develop a method to incorporate the modification into canola hybrid lines in such a way that it will be readily accepted by consumers concerned about genetically modified organisms.

**********

Web Links

New technology helps protect valuable canola crops from frost

Photo, posted August 29, 2018, courtesy of Tinker and Rove via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Eco-Friendly Agriculture

By Leave a Comment

Modern agriculture has steadily destroyed native grasslands, among other ecosystems.  In fact, farming is one of the most ecologically destructive things that humans do.  But we do have to eat.  In response, there is a growing movement for agrarian reform, from grain farming on the prairie, to agroforestry, to raising livestock more sustainably.  Efforts are accelerating to develop a kinder, gentler agriculture adapted to a changing world.

One such effort has come from the Land Institute, an organization in Kansas that works on natural systems agriculture, which seeks to retain the ecological stability of the prairie with its perennial seed plants along with a grain and seed yield comparable to that from annual crops.

After four decades of effort, the institute has introduced its first commercial grain, a trademarked variety called Kernza.  Kernza is a domesticated perennial wild grass – a so-called intermediate wheatgrass – that has a long, slender head that resembles wheat seeds.  People describe its taste as sweet and nutty.   Kernza is already being made into a cereal called Honey Toasted Kernza by Cascadian Farms.  Patagonia Provisions – a spin-off from the clothing company – is making beer from the new grain.

Although Kernza is already being grown and sold commercially, it is not yet ready for prime time.  Last year, there were only about 1,000 acres in cultivation and the yield is only a third to a tenth of the yield of wheat. 

Developing a sustainable perennial polyculture of edible plants would have major benefits such as not having to plow every year, plants developing large root systems that can reach water far beneath the surface and, without annual plowing, having soil carbon remain in the ground.

**********

Web Links

With New Perennial Grain, a Step Forward for Eco-Friendly Agriculture

Photo courtesy of Cascadian Farms/General Mills.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)