Bull Test, Snow Mold, Green Peach Aphid

WSU Co-sponsors 16th Annual Bull Test Sale

Cattlemen from throughout the Pacific Northwest gathered at Washington State University’s Irrigated Agriculture Research and Extension Center at Prosser late last month for the 16th annual All-Breed Bull Test Sale.

Co-sponsored by WSU and the Washington Cattlemen’s Association, the test sale has become one of the premier sales in the region. This year, representatives from 49 ranches purchased 76 bulls at the sale at an average price of $2,206. The top price was $5,600 for a Black Angus bull.

WCA receives membership dues paid by test consignors, paid advertising in the Ketch Pen livestock newspaper as well as 1 percent of the sale gross.

The test sale started last October, when 106 bulls from consigners arrived at Prosser. The consignors were required to show proof of negative BVD. Breeds included Black Angus, Chiangus, Gelbvieh, Herefords, Red Angus, Simmental and Simm-Angus.

Tested on a high-forage diet, the bulls were evaluated for growth, reproductive potential and carcass merit. Yearling bulls also were given a breeding soundness exam and sifted for structural soundness. Data from all of the tests is made available to consignors and potential buyers through periodic printed reports, through the sale catalog and on the bull test website at www.prosser.wsu.edu.

Mapping the Way to Improved Snow Mold Resistance

A genetic map being developed by scientists at Washington State University in collaboration with scientists at Japan’s National Agricultural Research Center on the northern island of Hokkaido may speed development of wheat varieties that are more resistant to snow mold.

Snow mold is a fungus-caused disease of wheat and other grasses. It’s prevalent in areas that have early snow and significant prolonged snow cover on ground that has not frozen. In Washington, that includes about 200,000 acres of winter wheat in Chelan, Douglas, Okanogan, Lincoln and Stevens counties. The fungus destroys the leaves and crown beneath the snow, commonly reducing yields between 20 percent and 40 percent. Fungicides are not cost effective. Improving genetic resistance is regarded as the best option.

Tim Murray, WSU professor of plant pathology, and Zenta Nishio, a wheat researcher with the NARCH, are testing genetic lines for snow mold resistance in growth chambers on the WSU campus where winter conditions can be simulated year-round. Nishio has developed a set of PCR primers that are being used in the lab to assess snow mold resistance. PCR is a laboratory technique that allows scientists to detect DNA specific sequences of an organism’s genes.

The scientists have evaluated 100 progeny lines from a cross of highly resistant wheat from Switzerland and very susceptible wheat from the Netherlands. They are now developing a genetic map that should allow breeders to use marker-assisted selection to identify resistant plants more quickly than with field or growth chamber testing.

Varieties with improved resistance to snow mold will have improved yield potential, thus providing growers with a greater selection of adapted, high-yielding, snow-mold resistant varieties from which to choose.

Protecting Potatoes by Monitoring Aphids

Green peach aphids have been a significant pest of potatoes in the Pacific Northwest for many years due to their ability to transmit plant viruses. Despite advances in integrated pest management and frequent use of pesticides, the potato industry is still plagued by aphids. Adding to the problem is the fact that the aphid also is occurring in seed production areas, which is increasing the risk of disease in seed stocks.

Since 1999, WSU professor Keith Pike has led a regional aphid monitor project with the Washington State Potato Commission. The project was initially established at the Commission’s request to keep the potato industry informed of green peach aphid activity and to provide early warning of potential problems.

“Average potato losses due to aphid-transmitted potato leaf roll virus are estimated at 10 percent but can reach levels of 25 percent or higher in fields subject to heavy aphid infestations,” Pike explained. “A loss of 10 percent equates to a shortfall of about $250 per acre.”

Green peach aphids that infest potatoes come from a variety of plants including peaches, nursery stocks, and various weeds. Early recognition and control is currently the main defense for minimizing aphids and spread of virus in fields.

Systemic insecticides protect against early season aphids, while foliar-applied materials (insecticides) give mid- to late-season control. Testing has shown that a few populations of the aphid are showing resistance to certain insecticides. This means that growers and other stakeholders need to take resistance management guidelines seriously, alternating between different types of insecticides, and where possible, shifting from reliance on broad spectrum insecticides to greater use of softer chemicals.

Pike’s team has been involved in field sampling of commercial fields during the growing season across the state’s major production areas in eastern Washington. They release the information and management recommendations promptly through Web postings and telephone hotlines across the state.

The project has promoted the use of systemic insecticides on all classes and varieties of potatoes, encouraged greater use of foliar-applied soft chemicals, determined levels of aphid resistance to select insecticides in the Columbia Basin and evaluated the benefits of parasitic aphid biocontrol. These efforts are leading to healthier potatoes and more environmentally friendly ways to control pests – a winning combination for the state of Washington.