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Urban Bee Environments Boost Pathogen Pressure

bee flowerResearchers from North Carolina State University have found that urban environments increase pathogen abundance in honeybees and reduce honeybee survival. The research team found that colonies closer to urban areas and those managed by beekeepers had higher pathogen pressure. “Overall, we found that the probability of worker [bee] survival in laboratory experiments declined threefold in bees collected from urban environments, as compared to those collected in rural environments,” says associate professor of entomology Steve Frank. However, the researchers also found that immune response was not affected by urbanization. Because immune response was the same across environments, researchers think the higher pathogen pressure in urban areas may be due to increased rates of transmission, which could be because bee colonies have fewer feeding sites to choose from in urban areas, so they are interacting with more bees from other colonies.

This article appears in the February 2016 issue of Acres U.S.A.

More Sustainable Strawberry Production

Plasticulture

Strawberry field

A team of researchers from North Carolina State University set out to provide strawberry growers with information that could help them transition to more sustainable soil and pest management production practices. Their study, published in HortTechnology, compares conventional, compost and organic strawberry production systems in the southeastern United States, and revealed good news for growers. All three systems resulted in positive net returns, and two showed “considerable reductions” in negative environmental and human health impacts.

According to the authors, the nonfumigated compost system and organic system resulted in reductions in negative environmental and human health impacts measured by a set of indicators. “For example, the total number of lethal doses (LD50) applied per acre from all chemicals used in each system and measuring acute human risk associated with each system declined from 118,000 doses per acre in the conventional system to 6,649 doses/acre in the compost system and to 0 doses per acre in the organic system,” the authors explained. “Chronic human health risk, groundwater pollution risk, and fertilizer use declined as well in the compost and organic systems as compared with the conventional system.”

This article appears in the December 2015 issue of Acres U.S.A.

Natural Coating Protects Alfalfa Seeds

alfalfa

Scientists have developed an alfalfa seed coating that is effective against several soilborne plant pathogens. Photo by Deborah Samac.

U.S. Department of Agriculture scientists have found that a natural seed coating can protect alfalfa against some soilborne diseases. Alfalfa is a $10 billion-a-year crop in the United States, but producing it can be a challenge. Farmers in the Midwest often plant it early in the spring when the soil is cold and damp. That makes the seeds vulnerable to a number of soilborne diseases.

To minimize the damage, most alfalfa seeds are coated with a fungicidal treatment. But the treatment, mefenoxam, is ineffective against the pathogen causing Aphanomyces root rot (ARR), which is common to Midwestern soils.

Demand for organic alfalfa for organic dairy operations is also increasing, and alfalfa treated with a fungicide can’t be labeled as organic. Many organic dairy farmers would like to expand but may face a roadblock due to a lack of available organic feed, according to Deborah Samac, a plant pathologist in the Agricultural Research Service’s (ARS) Plant Science Research Unit in St. Paul, Minnesota.

Samac wanted to see if coating alfalfa seeds with a naturally occurring mineral would protect them from soil diseases, including ARR. The mineral, zeolite, comes from degraded volcanic rock, has antifungal activity and qualifies as an organic soil treatment. Samac also wanted to assess zeolite’s effects on the health of plant roots and beneficial soil microbes. Continue Reading →

Yeasts Protect Fruit from Brown Rot

Yeasts Protect Fruit from Brown Rot Some naturally occurring yeasts may be useful for protecting stone fruits against pathogens that attack after harvest. USDA scientists looked to the microflora on the surface of the plum to find potential biocontrol agents against brown rot.

At the Agricultural Research Service (ARS) Appalachian Fruit Research Station in Kearneysville, West Virginia, plant pathologist Wojciech Janisiewicz and his colleagues determined that the surface of plums harbor several yeast species with excellent potential for use as biological controls against brown rot. Brown rot is caused by the fungus Monilinia fructicola.

Fruit surfaces are naturally colonized by a variety of microbes, including bacteria and yeast. Some of those native microorganisms have been shown to have a beneficial effect on reducing fruit decay after harvest.

In previous efforts, Janisiewicz developed a bacterium normally found on apples into a commercial biological control product that can be used instead of fungicides to control pome fruit diseases. The product is allowed in organic production. A lot of information exists about the benefits of natural fruit microflora on grapes and apples, but for plums, the extent of their potential for biological control of fruit decay remains largely unknown. Continue Reading →

Top Herd Health Problems, Natural Solutions

by Jerri Brunetti

The following reports are based on the gleanings of a number of animal owners who have utilized “traditional” methods on their livestock herd with various rates of success. These suggestions/reports have not been evaluated by the U.S. FDA and are not intended to act as a substitute for proper professional care, i.e. the diagnosis, prevention, treatment and prescriptions provided by licensed veterinarians. If your livestock suffers from any malady or health condition always consult with your veterinarian before utilizing any alternative methods of products.

Mastitis

Remove grain from diet; forages only. Herbs to be given orally per day: 2 bulbs garlic, 1 teaspoon cayenne, 1 ounce thyme, 1 ounce common sage. Half given in the morning and half in the evening. Use stimulating liniment (such as white liniment or Vicks on udder); milk out frequently (every couple of hours). Continue Reading →

Grafting May Aid Watermelon Crop

WatermelonsThe watermelon crop has declined dramatically in Washington because of disease, but Washington State University researchers are developing a solution that involves grafting watermelon plants onto squash and other vine plant rootstocks. “We’ve lost about a third of our state’s watermelon production over the last 10 years because of Verticillium wilt,” said Carol Miles, a professor of vegetable horticulture at the WSU Northwestern Washington Research and Extension Center in Mount Vernon. “Growers have switched to other crops that are less susceptible.” The fungus also affects tomatoes, potatoes, eggplant and many other crops and plants. “Grafting is very old technology, going back over 1,500 years in China,” said Miles. “Farmers in Japan have been grafting watermelon since the 1920s. In the Mediterranean region, farmers have been grafting watermelon, tomato and eggplant for almost 20 years. We just need to find out what works best for our region, and we’ll solve the Verticillium wilt problem.”

This article appears in the May 2015 issue of Acres U.S.A.