What’s breakfast without a glass of orange juice?

by Andrzej Czarniecki, Sustainable Plant Systems major

Photo Credit: Tim R. Gottwald and Steve M. Garnsey - USDA, ARS, U.S. Horticultural Research Laboratory, Florida

Photo Credit: Tim R. Gottwald and Steve M. Garnsey – USDA, ARS, U.S. Horticultural Research Laboratory, Florida

Orange juice may soon be a thing of the past. International researchers along with University of Florida and Florida State University researchers have received a 4 million dollar grant from the USDA in order combat Candidatus Liberibacter spp.  a devastating bacterial disease also known as Citrus Greening, or huanglongbing (HLB), or yellow dragon disease, which is known all around the world, affecting many other citrus growing countries and with no cure known. It is slowly killing off large orange production fields of Florida with up to 162,000 acres, as far as 50% of production has been cut in the last 4 years due with a $7.8 billion in revenue lost since 2007.

The disease enters the tree through a sap-sucking insect known as Diaphorina citri, the Asian Citrus Psyllid which feeds on the foliage of the plant allowing the bacteria to enter into the vascular system via the phloem and causing it to clog up. This causes the tree to starve itself from supplying proper nutrients resulting in fruit that is inferior in size, green, bitter which doesn’t allow for sales in the fruit market. There have been limitations such as not being able to culture the bacteria to send the bacteria to other researchers slowing down the process of finding a cure, therefore; scientists are trying a number of alternative different paths, such as; using  a bacteria similar in their study trials or by genetically modifying citrus trees with resistant genes from a spinach plant.

Researchers share $4 million USDA grant to attack citrus greening

This blog post was an assignment for Societal Issues: Pesticides, Alternatives and the Environment (PLNTPTH 4597). The views expressed are those of the author and do not necessarily reflect the views of the class, Department of Plant Pathology or the instructor.

Will They Survive?

bmsb_blogby Jennifer Fullenkamp, Sustainable Plant Systems major

I recently moved and noticed that there were a lot of brown marmorated stink bugs. I thought that it was just something with the house until I talked with some family members and friends. They too have noticed a rise in these stink bugs.

These bugs are a nasty pest with a strong, foul odor. Right when you think you disposed of the unpleasant critters, another is found right after the other. Unfortunately there is no good way to rid yourself of them. My mother and I have been finding them left and right, in every nook and cranny. A piece of advice: try to find where they are entering the house and block their entrance.

These little pests were first discovered in the U.S. in 2001. Since then, they have become an agronomical and house pest without many predators to control them or any insecticide to kill them.

Because they are not being picky eaters, the stink bug can cause a lot of damage on several varieties of plants (many fruit crops, common landscape plants and crops such as soybean and corn). The bugs eat the fruit and the leaves on plants, leaving behind perforated and destroyed crops and ornamental plants that cannot be used or sold.

I am fearful that marmorated stink bugs are going to be a pest that will take over and destroy a lot of food crops and ornamental plants that I work with every day. I dread what the world’s and my future might look like in the horticultural and floricultural industry in the next decade.

Still, there is one question that keeps playing through my mind. “What plants will survive this pesky pest?”

For more information on the marmorated stink bug:
Ohioline – Brown Marmorated Stink Bug fact sheet (pdf)

This blog post was an assignment for  Societal Issues: Pesticides, Alternatives and the Environment (PLNTPTH 4597). The views expressed are those of the author and do not necessarily reflect the views of the class, Department of Plant Pathology or the instructor.


Thousand Cankers Disease Hits Ohio

Curtis Utley, CSUE, Bugwood.org

Image: Curtis Utley, CSUE, Bugwood.org

by Stephen Marinkov, Communications major

Being from Ohio it is important for the natives to be educated on invasive species that can harm the state.  Thousand Cankers Disease is an invasive species caused by the fungus Geosmithia morbida.  The fungus is carried by the walnut twig beetle that bores into the trees, killing walnut and butternut trees in Ohio.

This fungus causes thousands of small cankers to form under the bark of the tree; the cankers eventually close up.  When this happens, nutrients and water intended for the branches and stem are cut off, killing the trees.
The Black walnut and butternut trees are most susceptible to the disease and natives should be informed of the symptoms.  Homeowners (?) should be aware of yellowing foliage where the leaves turn yellow and thinning in the upper crown of the infested tree.

Major spread of this disease is caused by human movement of wood products.  Natives need to be aware of the infected trees and limit the movement of potential infected trees.  The Great Lakes Early Detection Network (GLEDN) smart phone app is available as a free download.  This app contains images of Thousand Cankers Disease that users can look at to investigate possible infected trees.

As an Ohio native I want to spread awareness about invasive species that could harm this state.  If natives work together and combat diseases head on we can limit the deaths of so many trees.

More info > Ohioline Thousand Cankers Fact Sheet

This blog post was an assignment for  Societal Issues: Pesticides, Alternatives and the Environment (PLNTPTH 4597). The views expressed are those of the author and do not necessarily reflect the views of the class, Department of Plant Pathology or the instructor.

Sudden Oak Death Kills More Than Oaks

Photo: U.S. Forest Service

Sudden oak death is a disease of oaks and over 100 other trees, shrubs and ornamentals. Photo: U.S. Forest Service

It’s a bit misleading. Sudden oak death is indeed a serious disease of several oak species, but the disease also impacts over 100 trees, shrubs and ornamentals, making it a concern for our forests, landscapes and the ornamental and nursery industries > More info

Sudden oak is an invasive disease spreading in Northern California forests (and a small portion of Oregon), causing widespread death of infected trees.  Because the pathogen, Phytophthora ramorum, infects several ornamental species, nursery stock in California, Oregon and Washington are subject to regulations for dissemination and sale.

It’s not hard to imagine the consequences if sudden oak death were to spread acroo\ss the U.S.  There are very few management or treatment options that are environmentally safe, practical and effective in forest situations.  Ohio State scientists are studying how to determine how many and which trees are likely to survive in a given areas, based on genetic markers.

The work is being conducted by Pierluigi Bonello, professor in the Department of Plant Pathology at Ohio State, Anna Conrad, graduate student, and their colleagues.  Their work was recently published in Forest Ecology and Management (312:154-160).

Read more about their work in a recent CFAES news release > Will It Live or Die?

You don’t realize how important something is until it’s gone

white nose fungus on bats

Photo: U.S. Fish and Wildlife Service

Nearly 7 million bats – and counting – have succumbed to a fungus that has been spreading throughout the eastern U.S.

White nose syndrome, named for the visible white fungal growth on the noses of affected bats, has spread throughout the eastern U.S., including Ohio.  First documented in eastern New York in 2007, the fungus appears to infect hibernating bats, with a mortality rates 90 to 100%.

The fungus is believed to be an introduced species, in part because North American bat populations seem to have very low levels of immunity, or genetic resistance.  In contrast, European bat species and the white nose fungus appear to have evolved over time to co-exist.

In addition to tremendous ecological ramifications,  impacts include economic losses (estimated losses in agriculture: billions), public health (bats eat mosquitoes and other insects that may vector disease), and loss of tourism (cave tours and hiking contribute millions of dollars into area economies > here’s an example).

Working with the unknown – even in this day and age – presents several challenges.  Recent research at the University of Akron is helping put together some of the puzzle pieces.  Hannah Reynolds, lead author on this study featured in Science Daily, is currently a postdoctoral researcher in the Department of Plant Pathology.
> Read more

Learn more about bats and white nose syndrome > whitenosesyndrome.org

Valentine’s Day: Think Flowers . . .
and Invasive Pests

Valentine’s Day is a busy time for many businesses, but an article from Our Amazing Planet (LiveScience) reminds us that it’s also a busy time for the U.S. Customs and Border Patrol.  You might be surprised to learn that most cut flowers in the U.S. are imported, largely from South and Central America, and that Miami is the point of entry for the bulk of fresh cut flower shipments.

Inspectors serve as an important line of defense, examining incoming plant shipments for pests and disease pathogens. If something harmful should hitchhike its way into the U.S., it could establish a new “home” here and damage crops and animals as well as the environment.  In the U.S. alone, invasive species have an economic impact upwards of $100 billion (USDA).

Read the original article >
Stop and Frisk the Roses: Customs Agents Eye Valetines Flowers For Pests

Read more > invasivespecies.gov

Will this cold winter kill off invasive pests?

Emerald ash borer

Photo: Debbie Miller, USDA Forest Service, Bugwood.org

Maybe there’s a bright side to this historic winter in the Northeast U.S.  This cold weather is likely killing unwanted insects such as the emerald ash borer and the hemlock woolly adelgid. The emerald ash borer has spread throughout the northeast and Canada, damaging and killing ash trees in its wake.  The hemlock woolly adelgid, first detected in Ohio in 2012, threatens eastern hemlock and Carolina hemlock in the Eastern U.S.

Will it kill off the insects entirely? Unfortunately, no. Some insects will survive, somewhere, somehow. In time, the invasive pests will become established again. But a cold, hard winter like this will knock down populations and slow them down.

The headlines of this article from the philly.com reads, “Please, polar vortex, ice these garden pests.”  The article is about the brown marmorated stink bug, a pest of agricultural crops, landscapes and a nuisance in our homes. Unfortunately, stink bugs might be keeping warm in our attics and cracks in our walls.

Read more

> Please, Polar Vortex, Ice These Garden Pests (philly.com)

> Celebrating Deep Freeze, Insect Experts See a Chance to Kill Off Invasive Species (NY Times)

“Seeds on Katy Perry’s album triggers biosecurity alert from [Australia] Department of Agriculture”

This was the headline from Australia ABC News.

Katy Perry’s latest CD, Prism, includes packaging paper embedded with wildflower seeds (think green packaging).

General policy is that live plant material (including seeds) should not be transported across countries and certainly continents, and in many cases is regulated and/or illegal.  Australia enforces strict quarantine measures on the movement of plant material into the continent.

An internet search for the words “Katy Perry seeds Prism” will turn up a lot of headlines.  A subheadline from dailymail.co.uk explains the reasoning: “Fears they could be the host of a plant pathogen of biosecurity concern.”

It’s totally serious. Seeds, fruits and plants can harbor viruses, bacteria, fungi and other pests.  There are countless examples of invasive pests – Dutch elm disease, chestnut blight, emerald ash borer, Asian longhorned beetle, to name a few – which have been transported inadvertently across continents and now threaten native species.  The economic losses total in the billions of dollars.

It might sound far-fetched, but these regulations have a sound scientific basis.  > More info

“The Colors of Fall: Are Autumn Reds and Golds Passing Us By?”

The rich colors of the autumn leaves in this photograph (taken on campus) reminded me of an article by the National Science Foundation Long-Term Ecological Research (LTER) Network series: “The Colors of Fall: Are Autumn Reds and Golds Passing Us By?”

Several changes are afoot. Chestnut blight (a plant disease) has wiped out the majestic chestnut trees, which used to blanket forests with bright yellows and golds in the autumn. Hemlocks are threatened by the woolly adelgid, an invasive insect.  Drought and land use are also changing the forest landscape, exacerbated by a changing climate. 

There really isn’t any good news here, but it’s important.  These crises (plural) need our attention > Read full NSF article

Here’s a related article about current genetics and breeding research on chestnuts > APSnet article


Spring 2014: Molds, Mushroom and Mankind (PLNTPTH 2000) General Education course for non-science majors, Natural Science > Biological Science, w/o lab > More info