crop

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

Making Cotton More Sustainable | Earth Wise

August 16, 2022 By EarthWise Leave a Comment

In the United States, cotton is a $7 billion annual crop grown in 17 states. Cotton plants in the largest producing countries in the world – India, China, and the U.S. – are genetically very similar and, like other crops that lack diversity, can be at risk.

Cultivated cotton around the world has been bred to look and act very similar. It is high yielding and easy to harvest using machines. But it is also wildly unprepared to fight disease, drought, or insect-borne pathogens.

Researchers are looking beyond breeding for ways to combat the low genetic diversity of cultivated cotton. There are new approaches that combine breeding with elements of genetic modification. Most cotton in the U.S. has already been genetically modified to resist caterpillar pests. But as new problems emerge, new solutions will be needed that may require complicated changes to the cotton genome. Getting regulatory approval for a genetically modified crop is a long and expensive process.

However, ordinary genetic modification is not the only possibility. Modern genetic sequencing technology can allow researchers to examine various wild cotton varieties and identify the genetic markers for desirable traits. Once valuable genes in wild species have been identified, traditional plant breeding techniques could be used to produce cultivated cotton varieties that are more resistant to disease and drought.

Climate change is raising average global temperatures and some important cotton-producing regions such as the U.S. Southwest are becoming drier. Researchers are hoping to produce cultivated cotton that can tolerate drought at the seedling stage. The ultimate goal is to create more sustainable and genetically diverse cotton that can thrive in a changing world.

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Cotton Breeders Are Using Genetic Insights To Make This Global Crop More Sustainable

Photo, posted November 9, 2008, courtesy of BP Takoma via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaner Water Using Corn | Earth Wise

May 12, 2021 By EarthWise Leave a Comment

Corn is the largest agricultural crop in the U.S., and it is also one of the most wasteful. About half of the harvest ends up as stover – corn stalks, leaves, husks, and cobs – once the kernels are used for food.

Corn stover has relatively few commercial or industrial uses. It can be used to produce biofuel, but that is not very energy efficient. It is sometimes used as a low-quality livestock feed as well. Mostly, it is just burned if it is used at all.

Researchers at the University of California Riverside have developed an energy-efficient way to make good use of stover by transforming it into activated carbon for use in water treatment.

Activated carbon – often called activated charcoal – is an organic material that is specially treated to contain millions of microscopic pores that make it highly absorbent. It has many industrial uses, the most common of which is for filtering pollutants out of drinking water. Most household water filters such as Brita filters as well as the ones built into refrigerators make use of activated carbon.

The Riverside researchers explored methods for producing activated carbon from charred corn stover and found that processing the material with hot compressed water – a process known as hydrothermal carbonization – produced highly absorbent activated carbon with superior properties compared to material produced by slow pyrolysis, where corn stover is charred at increasing temperatures over a long period of time.

According to the researchers, it is important to create approaches that convert waste into high-value materials, fuels, and chemicals in order to create new value streams and eliminate the environmental harm that comes from a so-called “take-make-dispose” economic model.

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Cleaner Water Through Corn

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

Earth Wise is a production of WAMC Northeast Public Radio.

Prickly Pear As A Sustainable Crop | Earth Wise

April 6, 2021 By EarthWise Leave a Comment

The fruits and pads of opuntia, better known as prickly pear cactus, find their way into people’s diets in many arid and semi-arid places around the world. In Mexico, the pads are known as nopales and are used in a variety of dishes. The pears themselves are used in jams, salads, and juices.

A five-year study by the University of Nevada Reno College of Agriculture, Biotechnology & Natural Resources investigated the prospects for cactus pear to become a major crop like soybeans and corn and to help provide a biofuel source.

As the climate changes, dry areas are going to get dryer and drought issues will increasingly affect traditional crops.

The study looked at the particular opuntia species called the spineless cactus pear and found that it had the highest fruit production while using up to 80% less water than some traditional crops. Cactus pear can be used for both human consumption and livestock feed. As a perennial crop, once the fruit and pads are harvested for food, the remaining biomass can be used for biofuel production.

Corn and sugar cane are the most utilized bioenergy crops right now, but these use three to six times more water than cactus pear. The cactus pear productivity is on par with corn and sugar cane, but not only do they use a fraction of the water, they also have higher heat tolerance.

Over 40% of land area around the world is classified as semi-arid or arid. There is enormous potential for planting cactus for carbon sequestration. If nothing else, it makes great sense to grow cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops.

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Study shows cactus pear as drought-tolerant crop for sustainable fuel and food

Photo, posted April 16, 2020, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Self-Watering Soil | Earth Wise

December 9, 2020 By EarthWise Leave a Comment

Researchers at the University of Texas at Austin have created a new type of soil that can pull water from the air and distribute it to plants. Such soil has the potential to expand the map of farmable land to previously inhospitable places as well as to reduce water use in agriculture in an era of growing droughts.

The team’s atmospheric water irrigation system makes use of super-moisture-absorbent gels to capture water from the air. When they are heated to a high enough temperature, the gels release the water, making it available to plants.

The gels in the soil pull water out of the air during cooler, more humid periods at night and when the sun heats the soil during the day, the water-containing gels release their contents into the soil.

Each gram of soil can extract about 3-4 grams of water. Depending on the specific crop, somewhere between a couple of ounces and 2 pounds of the soil can provide enough water to irrigate a square yard of farmland.

Experiments on the soil found that it retains water better than the sandy soils found in dry areas and needs much less water to grow plants.

In one experiment, radish plants germinated in the soil all survived a 14-day period without any irrigation beyond the initial watering when they were planted. Radish plants in ordinary sandy soil irrigated for the first four days of the experiments lasted no more than two days further without watering.

The Austin group has been developing gel-polymer materials that work like super-sponges for two years. These materials extract large amounts of water from the ambient air, clean it, and release it when heated with solar energy.

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Self-Watering Soil Could Transform Farming

Photo, posted October 21, 2020, courtesy of the U.S. Department of Agriculture via Flickr. USDA Media by Lance Cheung.

Earth Wise is a production of WAMC Northeast Public Radio.

Sunlight As A Cash Crop

July 10, 2019 By EarthWise Leave a Comment

It isn’t so easy to be a farmer these days. Farming has always involved long hours, hard work and the uncertainties of weather and yield. The 21st Century has added new and unique challenges such as increasingly unpredictable weather, insect infestation and disease, and low commodity prices. Add in sudden tariffs and farmers struggle even more to make ends meet. The default rate for farmers’ loans is the the highest in at least nine years.

One thing that remains reliable for farmers is the sun. It rises in the morning and goes down at night. The sun can be trusted, unlike politicians, rain, or commodity prices. These days, many farmers are taking advantage of the dependability of the sun to make money from a new cash crop: solar energy.

The trend is spreading. North Carolina has been a leading solar energy state for several years and a 2017 report found that solar energy generates 30% of the income of many farms. Typical annual rent payments for farmland by solar companies range from $500 to $1,400 per acre in North Carolina.

A growing list of states have clean energy mandates targeting 100% use of renewable energy. These mandates provide incentives for farmers that make installing solar a financially smart decision and falling prices for solar installations make it an even better deal.

Solar works well when co-located on a farm and can be built in ways that minimizes impact. It is quiet, uses almost no water, doesn’t pollute, and if it is decommissioned, the land can go back to its previous use. If the solar facilities are raised up, the same land can be used to graze livestock or grow shade-tolerant crops.

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Harvesting the sun is the new cash crop

Photo, posted December 25, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Crop Diversity

March 22, 2019 By EarthWise Leave a Comment

A study at the University of Toronto suggests that on a global scale, we are growing more of the same kinds of crops, and this diminishing diversity presents major challenges for agricultural sustainability.

In some places, for example here in North America, crop diversity has actually increased. Back in the 1960s, North Americans grew about 80 crops. Now there are 93.

But on a global scale, more of the same kinds of crops are being grown on much larger scales. Just four crops – soybeans, wheat, rice and corn – occupy nearly 50% of the world’s entire agricultural lands. The remaining 152 crops cover the rest. Large industrial farms often grow one crop species – usually just a single genotype – across thousands of acres of land.

This decline in global crop diversity is problematic in several ways. On a cultural level, it threatens regional food sovereignty. If regional crop diversity is threatened, it makes it more difficult for people to eat or afford foods that are culturally significant to them.

On an ecological level, the dominance by a few genetic lineages of crops makes the agricultural system increasingly susceptible to pests or diseases. The deadly fungus that is threatening the world’s banana plantations is a prime current example. The Irish potato famine in the 19^th century is a tragic historical example.

As large industrial-sized farms in Asia, Europe and the Americas start to look more and more alike, the dangers of large monocultures of crops that are commercially valuable will only increase. It will be important for global governments to consider the impact of policies that affect the diversity of the agricultural system and its sustainability in an increasingly hungry world.

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A small number of crops are dominating globally. And that’s bad news for sustainable agriculture

Photo, posted August 13, 2012, courtesy of Alasdair McKenzie via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hacking Photosynthesis

February 25, 2019 By EarthWise Leave a Comment

There is an enzyme known as RuBisCo that is involved in carbon fixation, the process plants use to convert carbon dioxide into sugar molecules. The RuBisCo molecule is inside the leaves of most plants and is probably the most abundant protein in the world.

RuBisCo picks up carbon dioxide from the air and uses energy from the sun to turn the carbon into sugar molecules. This process of photosynthesis is pretty much the foundation of life on Earth.

Wonderful as it is, the process is not perfect. RuBisCo is not very selective in grabbing molecules from the air. It picks up oxygen as well as CO₂ and it produces a toxic compound when it does that.

Plants operate a whole other complicated chemical process to deal with this toxic byproduct and uses up a lot of energy along the way, leaving less energy for making leaves or food that we can eat.

A research program at the University of Illinois called Realizing Increased Photosynthetic Efficiency (or RIPE) has been trying to correct this problem; they have been trying to hack photosynthesis. And they may well have succeeded.

Using genetic modification on tobacco plants, they have shut down the existing detoxification process and set up a much more efficient new one. The result is super plants that grow faster and up to 40% bigger.

The next step is to get it to work on plants that people actually rely upon for food, like tomatoes, soybeans and black-eyed peas (which are a staple food crop in sub-Saharan Africa where food is scarce.)

It will be years before we know if the process can really produce more food and be safe, but it may end up leading to a major increase in crop productivity.

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Scientists Have ‘Hacked Photosynthesis’ In Search Of More Productive Crops

Photo, posted June 10, 2013, courtesy of Boon Hong Seto via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bad News For Beer

November 28, 2018 By EarthWise Leave a Comment

As extreme weather events become increasingly common, arctic ice disappears, and wildfires burn for weeks on end, many people wonder just what it will take to change some of the entrenched opinions about climate change.

[Read more…] about Bad News For Beer

Using Rye To Grow Edamame

April 17, 2018 By EarthWise Leave a Comment

Herbicide-resistant weeds are becoming a more and more common problem for farmers growing grain and vegetable crops. As a result, the farmers are looking for alternatives to herbicides to control weeds. One promising approach is the use of cover crops, which are planted in the off season to protect the soil. Thick cover crop growth can often compete well with weeds during the cover crop growth period, and can prevent most germinated weed seeds from completing their life cycle and reproducing.

Small Grains In Corn Country

January 31, 2018 By EarthWise Leave a Comment

Large portions of the Midwest are called the Corn Belt and for good reason. Overall, about 90 million acres or 140,000 square miles of the United States are planted with corn and about half of that is in Iowa, Illinois, Nebraska and Minnesota. In most of the Corn Belt, the corn is planted in rotation with soybeans. Both are warm weather crops and the soil is left barren for nearly half of the year when the two crops are out of season.

Climate Change And Barley

January 10, 2018 By EarthWise Leave a Comment

The impacts of increased carbon dioxide and the changing climate are often complicated and, it turns out, not always negative. In some areas of the world, people can actually benefit from increased CO2 and climate change. Barley, the most important feed crop for beef production in Alberta, Canada, as well as the province’s beef industry itself actually stand to gain from the changes that are most assuredly not a good thing for much of the world.

Is A Real Christmas Tree Or A Fake One Better for the Planet?

December 7, 2017 By EarthWise 2 Comments

For many, the Christmas tree is a quintessential part of the holiday season. According to the American Christmas Tree Association, 81% of Christmas trees Americans decorated in 2016 were artificial. But are artificial trees really the better option for the environment?

Saving Bees With Software

April 11, 2017 By EarthWise

The worldwide decline in the population of bees and other pollinators has impelled farmers to do what they can to encourage and nurture bees on their land. Protecting bees is important because pollinators are essential for growing many foods including coffee, cacao, almonds and many other fruits and vegetables.

Is Coffee Endangered?

October 5, 2016 By WAMC WEB

There are many worries related to climate change, notably the increasing occurrence of extreme weather events, melting polar ice, rising seas, and so forth. But perhaps one of the most ominous warnings comes from a new report issued by the Climate Institute about the future of coffee.

Solar Power As A Crop

December 15, 2015 By WAMC WEB

The historic, relentless drought in California has caused a number of the state’s farmers to start planting photovoltaic panels instead of crops. Because of the drought, Federal water deliveries to farmers in the Central Valley and elsewhere have been dwindling. As a result of the water shortage, more than 500,000 acres will lie fallow this year.