MycoRant

The wet year of 2009 has lead not only to good production of wild mushrooms, but outbreaks of plant pathogenic fungi as well. Economically valuable crops are under attack by a variety of fungal pests that seem to be on quite a roll this year.

Blueberry

Maine’s Wild Blueberry Crop Healthy, Despite Wet Weather: “Maine’s blueberry crop is healthy, despite this summer’s heavy rain.  Maine Wild Blueberry Commission Executive Director David Bell says the crop isn’t record-breaking, but the berries are ‘high quality.’”

Disease Alert: Valdensinia Leaf Spot, NEW disease in Maine (PDF)

Maine’s Blueberry Crop Imperiled by Leaf spot Fungus: “With fog swirling around her, Seanna Annis, a blueberry pathologist at the University of Maine, scanned the low bushes along a gravel road through the blueberry fields Sunday evening. She stopped, brought out a magnifying lens and pinched a leaf from a plant.”

Maine Blueberry Field Infected with Fungus: “Maine has extensive blueberry fields and relies on them to bolster the economy. Widespread infections and subsequent destruction of the fields could be devastating for the State and especially the farmers who rely on the blueberry crops as their means of income.” This blog post includes some comments from the Maine blueberry pathologist who is at the forefront of coping with the disease.

Walnut

Fungal Disease Attacks Black Walnut Trees in West: “The disease is caused by a previously undescribed fungus hitchhiking on a tiny bark beetle native to California and widely distributed from San Diego to Shasta counties.”

Beetle and Fungus One-Two Punch Threatens Black Walnut Trees, Scientists Warn: “The fungus, with its barrel-shaped spores, appears to be an undescribed and perhaps exotic species within the genus Geosmithia, said postdoctoral researcher Andrew Graves of the UC Davis Department of Plant Pathology. Graves, part of a Davis-based team working on the project since June 2008, has noted that there are seven named species of Geosmithia.”

Wheat

Killer Fungus Threatens Asian Breadbasket: “A killer fungus commonly known as Ug99 (Uganda-99) destroyed Iranian wheat fields in the 2008 wheat season. Wheat crop suffers from three types of rust diseases: Brown, yellow and black or stem. Of the three rusts, black rust was under genetic control globally since the last five decades. However, it remained as an endemic problem in east Africa (Uganda and adjoining countries). It was in 1999, a mutated form of black rust pathogen suddenly evolved in Uganda, scientifically designated as TTKS and commonly known as Ug99, which destroyed all Ugandan wheat fields the following season. Stem rust is a catastrophic disease because of its ability to cause complete annihilation of wheat crops over wide areas. The rust fungus produces numerous tiny spores and migrates from one country to another with the help of winds.”

Disease Threatens Afghan Wheat: “In Afghanistan, nearly all of the farmers grow wheat to feed their families or to sell. With the disease knocking on Afghanistan’s door from neighboring Iran, experts say an outbreak of stem rust would be a serious blow to a country already reeling from an ongoing drought and decades of armed conflict”

Previous MycoRant Post on Ug99

Peanuts

Peanut Farmers Tackling Fungus in Gaines County: “The West Texas Plains might look a little greener than they did this time last year, but for our area peanut farmers, rain isn’t good news. The moisture and humidity creates a fungus on the peanut pods and there’s been a growing concern for fungus.”

Potatoes

It’s not a fungus but… Fungus Threatens State’s Potato Crop: “A highly contagious and destructive fungus – already found on tomato plants in Wisconsin – has been confirmed in potato fields in two counties, state agricultural experts said Thursday. The fungus was discovered in Columbia and Portage counties, two of the eight counties with confirmed cases of late blight in tomatoes. The infestation spreads quickly by air, with spores traveling long distances.”

The Answer to Potato Blight: “When the Soviet bloc broke up, the chief scientist hid his disease-resistant tubers under his bed and carried on breeding independently in secret. The potatoes came to the West’s attention when Scottish breeders noticed an unaffected crop amid a blight-ridden trial. The foliage was tall and entirely healthy. After careful negotiation, the research project moved to Bangor, in Wales, and blight-resistant potatoes with the Sarpo prefix began to appear about five years ago.”

Potato Blight Found in Red River Valley:  “Blight has been found in potato crops in the Red River Valley, raising fears of widespread damage. Northern Plains Potato Growers Association President Chuck Gunnerson said several cases of blight have been found. He said weather over the next three weeks will determine how quickly the disease spreads… Potato blight was reported in several states and Canada this year. Gunnerson said it’s believed the disease came from tomato plants sold by several large national retail stores.”

Tags: blueberry, phytopathology, potato blight, Ug99, walnut