Carnivorous Plants: Skipping the Insects for a Second Helping of Pollution

Human’s destructive practice of burning fossil fuels is leading carnivorous plants to switch their diet. While examining the common sundew drosera rotundifolia, a plant native to Swedish bogs, scientists from England’s Loughborough University found that scores of the small plant were eating less insects (their “meat” source) and were rather getting their fill off of pollution.

Plants like the common sundew derive much of their necessary nitrogen from insect-based sources. To get their food, the plant secretes a sticky mucous-like substance from the glandular hairs on its leaves; insects are then attracted to the hair’s bright color and sweet taste and end up becoming caught on the surface. As the insect dissolves into the plant, the common sundew absorbs all the necessary nitrogen. While most non-carnivorous plants are able to soak in nitrogen from the ground, plants like the common sundew have had to adapt in order to live in areas where nitrogen levels are less available.

Nitrogen (a byproduct of industry) reaches soil after being released from factories and other fossil fuel burning devices; it is then soaked up in clouds and eventually rained back down onto the earth and soaked into the ground. In areas highly affected by fossil fuel pollution, nitrogen accumulates in the ground and makes its way to the roots of a variety of plant life. Nitrogen levels in the soil become high and can disrupt the normal processes of the vegetation dependent upon it.

After collecting numerous samples of the common sundew, researchers were able to determine how much plant’s nitrogen intake came from insect-based sources and how much came from the nitrogen-infused soil. The two could be differentiated because nitrogen from insects has a different makeup of isotopes than nitrogen that has fallen down in rain. According to their findings, insect-based nitrogen only made up about 22 percent of the common sundew’s nitrogen levels, compared to the control group’s (plants will significantly less pollution interference) 57 percent.

And the issue here goes deeper than the plants simply skimping out on the occasional meal. Besides eating fewer bugs, the plants are beginning to change its form to better adapt to its changing (and more nitrogen-enriched) environment. The sticky substance that acted as the plant’s insect trap is becoming less and less sticky, and the bright attractive red color is beginning to turn green—this would suggest that the plant is gearing up for photosynthesis, and not capture and kill. “If there’s plenty of nitrogen available to their roots, they don’t need to eat as much,” explained Dr. Jonathan Millett from Loughborough University, and head author of the study.

But what does this mean for the environment? Well it could mean a slew of things: first, it could that the common sundew, and other carnivorous plants like it, may fall back to its vegetarian ways—pre-evolutionary change that brought it to wear it is no—thus eliminating its species-specific trick. The switch away from meat-based nutrition could also be an example of how inefficient nutrient consumption through animal-based means can be. Yet, what is certain is the fact that our industrialized ways are making a profound impact on the world in which we live.

 

Photo Credit: commons.wikimedia.org/wiki/File:Drosera_rotundifolia_on_Yew_Tree_Heath,_New_Forest_-_geograph.org.uk_-_184332.jpg

Rare Plant Collection Threatened by Development

By: Nick Engelfried 

September 19, 2010

As global warming continues to alter the Earth’s climate, the genetic diversity of food plants will become more and more important as a way to ensure survival for many crop species.  As climates change in countries all over the world, plants may react in unforeseen ways, and varieties that once thrived in a particular environment may no longer do well there.  Meanwhile global warming could cause the spread of plant diseases, posing challenges as farmers try to find more disease-resistant strains.  Now-obscure varieties of food plants, developed decades or centuries ago through years of methodical breeding, could help nations survive global warming by providing farmers with resistant genes to experiment with. 

But in the Russian village of Pavlovsk, close to the city of St. Petersburg, one of the world’s premiere strongholds of domestic plant diversity is now threatened with extinction.  The Vavilov Institute of Plant Industry, where scientists have bread rare and heirloom plant varieties for decades, is in danger of being auctioned off by the Russian government to real estate developers.

In a famous story from World War II, Russian scientists at the Vavilov Institute reportedly allowed themselves to starve to death rather than abandon their post guarding rare plant varieties against invading German forces.  Like scientists today, these researchers saw the Institute’s repository of plants a valuable resource for those seeking to develop new or better crops, and an asset for both Russia and global agriculture.  Yet in an age where agriculture is increasingly dominated by a few crop varieties mass-produced on industrial farms, collections like the Vavilov Institute’s are no longer as highly valued.  Now real estate companies are eyeing the lands around St. Petersburg, and have offered to buy up Institute land and convert it to housing developments.

As the Russian government moved to sell off the land last month, scientists and food diversity activists responded with international outrage.  Leading plant researchers from around the world criticized the idea of putting Vavilov’s plant collection in jeopardy, and Internet activists tweeted their concerns at Russian President Dmitry Medvedev.  The outcry was great enough that the Russian Housing Development Foundation has said it is postponing auctioning off the land, partly to collect more information about the Vavilov Institute’s value.  The auction could still take place as soon as October, unless Russia’s government makes a concrete commitment to preserving the land.

Scientists say ninety percent of the plant varieties at Vavilov are found nowhere else in the world, meaning significant genetic diversity would be lost if the land is destroyed.  Because many of the plants are deep-rooted trees and shrubs that cannot be safely moved, re-locating the collection does not seem to be a viable option.  Groups and individuals concerned about the possible loss of biodiversity are still pressuring the Russian government to protect the Vavilov Institute, and Care2.com has created a petition to President Medvedev, asking that the collection of rare plants be saved.

“As a result of public pressure, thousands of precious plants have been granted a temporary reprieve,” writes Jaelithe Judy of Care2.com.  “But there is still more work to be done.”  With the Russian government deciding how to respond to public criticism of the land auction, the next few weeks may decide the ultimate fate of the Vavilov Institute’s botanical gene bank. 

Photo credit: Luigi Guarino, and Luigi Guarino