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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.

Preventing Tomato Blossom-End Rot

800px-Blossomendrot

Plants are subjected to numerous environmental stresses — drought, extreme temperatures and excess light can all affect plant growth and quality. Looking for methods to improve the quality of tomato plants, researchers at the University of Tennessee turned to abscisic acid (ABA), a plant hormone known to help plants acclimate to these types of severe environmental stresses. The research results and recommendations for growers were published in HortScience.

According to the study’s corresponding author Carl Sams, ABA can have a positive effect on nutritional fluxes in plants; for example, it can promote the uptake of calcium in tomato plants. Adequate levels of calcium in tomato fruit have positive effects on fruit quality — specifically firmness — while insufficient calcium uptake and movement in tomato plants can result in a disorder called blossom-end rot. Blossom-end rot often occurs in plants that have an adequate calcium supply but are grown in challenging environmental conditions such as humidity, high light intensity and high temperatures, all of which inhibit transport of calcium to plants’ rapidly growing distal fruit tissue. Blossom-end rot can also occur when plants experience increased demand for calcium in the early stages of fruit development.

This summary appears in the March 2015 issue of Acres U.S.A.