Earth Wise

A look at our changing environment.

You are here: Home / Archives for tomatoes

tomatoes

Bumblebees And Climate Change | Earth Wise

By Leave a Comment

Pollinators, such as bees and bats, are vital for global food production.  They provide an ecological service that’s necessary for the reproduction of nearly 75% of the world’s flowering plants, including more than two-thirds of global food crops.

Bumblebees are among the most important plant pollinators.  They pollinate many food crops, including apples, tomatoes, blueberries and legumes, as well as countless types of trees, shrubs, and wildflowers.

According to a new study by researchers from Simon Fraser University in Canada, temperature changes have negatively impacted most bumblebee species during the past 120 years.  The research, which was recently published in the journal Biology Letters, found that these changes in temperature had more of a negative impact than other factors such as precipitation or floral resources. 

The research team analyzed existing data on 46 bumblebee species across North America between 1900 and 2020.  The researchers created two occupancy models – one that was focused on time and the other that focused on environmental factors – to see how climate change and land-use variables impacted species’ occupancy.  They found that six bumblebee species decreased through time, 22 increased, and 18 remained stable.

Temperature changes had primarily negative impacts on bumblebees.  In fact, 37 of the 46 species studied exhibited declines or less positive occupancy increases under observed changes in temperature when compared with temperatures remaining constant.  Approximately half of the bumblebee species were negatively impacted by changes in precipitation or floral resources while the other half were positively impacted.

Bumblebee populations are changing as a consequence of climate change. 

**********

Web Links

The American Bumblebee

Climate change negatively impacting bumble bees: Study

Photo, posted July 14, 2019, courtesy of Dmitry Grigoriev via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Cell Greenhouses | Earth Wise

By Leave a Comment

A recent study at North Carolina State University has shown that it can be feasible to use see-through solar panels in greenhouses to generate electricity.  The idea is to use semi-transparent solar panels on greenhouses that allow some of the light to get in for the plants to grow while making the greenhouses energy neutral or even allowing them to generate more power than they use.

The question is how the semi-transparent solar panels might affect greenhouse crops.  To investigate this issue, researchers grew crops of red leaf lettuce from seed to full maturity under a standard set of growing conditions – temperature, water, fertilizer, and CO2 concentration – but varied the light they get. 

A control group was exposed to the full spectrum of white light while three experimental groups were exposed to light through different types of filters that absorbed the particular wavelengths of light that would be absorbed by different types of semitransparent solar cells.

The researchers paid close attention to characteristics of the lettuce that are important to growers, grocers, and consumers:  general appearance, leaf number, leaf size, and weight.  The results were that the lettuce produced using all three kinds of filtered light was essentially identical to that produced in the control group.    Further research is underway looking at how harvesting various wavelengths of light affects biological processes for lettuces, tomatoes, and other crops.

Getting growers to use solar-powered greenhouses would be very difficult if doing so would result in a loss of productivity.  But given these experimental results, it appears as though the decision will boil down to a simple economic argument about whether the investment in new greenhouse technology would be offset by energy production and its resultant savings.

**********

Web Links

Study Finds Plants Would Grow Well in Solar Cell Greenhouses

Photo, posted April 8, 2008, courtesy of Brian Boucheron via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Crops May Need To Move | Earth Wise

By Leave a Comment

California has unique micro-climate diversity that creates ideal growing conditions for a wide range of crops.  One third of the vegetables and two-thirds of the fruits and nuts we eat in this country are grown on the more than 76,000 farms in California.  But as the climate continues to change, many farmers have started to worry about where and when crops can be grown in the future.   Within the next 20 years or so, some parts of California may become too hot and dry to sustain agricultural production.

According to new research from the Lawrence Berkeley National Laboratory, by the years 2045-2049, warmer temperatures will have a significant effect on cool-season crops such as broccoli and lettuce such that their growing season will need to shift.  On the other hand, warm-season crops like cantaloupe, tomatoes, and carrots will need to move to entirely new growing locations.

The study looked at five key crops that are produced more in California than elsewhere and studied the climate conditions under which they prosper and those under which they fail.  They established the range of conditions for which the crops can remain successful.  Finally they looked at climate projections for various parts of the state.

California’s agriculture is an essential part of our food security, so it is important to predict how future warming will affect when and where crops can be grown.  Changing these things presents challenges.  For example, when considering relocating crops, growers have specialized knowledge of their land and their crops.  If crops need to move to a new area, either the farmers have to move to that area, or they have to grow a different crop.  Either way, it presents a practical and economic burden on the farmer.

**********

Web Links

Some of America’s Favorite Produce Crops May Need to Get a Move On by 2045

Photo, posted June 16, 2011, courtesy of the U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hacking Photosynthesis

By 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.

**********

Web Links

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.

The Tiny Country That Feeds The World

By Leave a Comment

The Netherlands is a small, densely populated country with more than 1,300 inhabitants per square mile.  It lacks almost every resource one associates with large-scale agriculture.  Nevertheless, it is the number two exporter of food in the world, second only to the United States, which is almost 300 times bigger.  The Dutch lead the world in exporting tomatoes, potatoes and onions and produce many other crops as well. 

[Read more…] about The Tiny Country That Feeds The World

Restoring The Taste Of Tomatoes

By

Over the years, tomatoes have been selectively bred for qualities such as size and firmness for shipping purposes and appearance, but selection for flavor has generally been overlooked.  Many of us find that the tomatoes we buy in the grocery store just don’t taste like they used to.  In fact, often they don’t taste like much of anything.  Comparing them to the delicious local-grown varieties we can find during the summer provides evidence for this conclusion.

[Read more…] about Restoring The Taste Of Tomatoes

WAMC Northeast Public Radio

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