May 21, 2007
Contacts: Dr. Donald R. Viands, Cornell University, 607-255-3081
Dr. Elson J. Shields, Cornell University, 607-255-8428

Note: ASB fact sheets are found online at www.nnyagdev.org

Cornell Researchers and Farmer Report More Progress Against Pest Peculiar to Northern New York

Alfalfa snout beetle is an invasive insect pest peculiar to Northern New York and parts of Canada across the St. Lawrence River. The alfalfa snout beetle (ASB) eats the roots of alfalfa, destroying a vital forage crop for dairy cattle and other livestock. Field surveys funded by the Northern New York Agricultural Development Program in 2005 and 2006 show the areas infested with ASB continues to expand in Franklin, Jefferson, Lewis and St. Lawrence counties. Cornell University researchers funded by the Northern New York Agricultural Development Program are advancing two promising control methods for the destructive agricultural pest.

Dr. Donald R. Viands, a plant breeder at Cornell University, is developing ASB-resistant alfalfa varieties. He says, �We have seen the first true evidence that breeding can increase the ASB resistance levels in alfalfa. Our ultimate goal is to develop ASB-resistant alfalfa varieties that are persistent and productive.�

Developing resistance in plants, however, takes time and patience. In 1998, Viands evaluated 173 alfalfa plant populations collected near Watertown, NY. Some plants showed ASB resistance at a low level.

�First, we identified the plants with resistance genes, then we selected the best of those plants and began the long-term breeding process to build up the resistance in the alfalfa varieties with the greatest potential for success,� Viands says.

Alfalfa varieties grown in Hungary where the alfalfa snout beetle is native were obtained as an ASB-resistant gene selection source for the project.

�Over time and several cycles of selection the frequency of the resistance genes in the plants increases. Since 2003, Jamie Neally, a member of our ASB research team, has completed three to four cycles in 15 different plant populations showing lower level root damage in greenhouse trials,� Viands says.

Because insect pressure in farm fields is not uniform, field screening of plants bred for resistance to ASB exposure can be unreliable as an evaluation method. So, with a Northern New York Agricultural Development Program grant, Viands, Dr. Elson J. Shields of Cornell University�s Department of Entomology and Research Support Specialist Anthony Testa developed a reliable greenhouse screening protocol. The method allows the researchers to control the insect pressure on the plants by controlling the number of insect eggs applied to each plant and the length of time the insect larvae are allowed to feed on the alfalfa roots.

One plant population in the greenhouse showed the level of damage decreasing from a score of 3.86 (a score of 1 indicates no root damage, 5 equals a totally destroyed root or a dead plant) to 2.90 after three cycles of selection.

Field evaluation of the most-resistant alfalfa varieties will begin on Northern New York farms in 2008.

Jefferson County Farm Harvesting Results of Patience with Research Project
The plant populations showing promise include varieties chosen from the most elite in the Cornell Forage Breeding Program, varieties from Hungary, and plants identified on the John Peck farm in Jefferson County, NY. Since 2003, a total of 83,000 plants have been evaluated.

Viands says the development of ASB resistance varieties used in combination with other control measures will provide increased protection from the pest to the alfalfa crop in Northern New York. Shields has identified and been testing biological control organisms, namely entomopathogenic (insect-killing) nematodes, that are showing promise in field trials at the Peck farm near Great Bend.

Shields introduced nematodes native to New York on the Peck family farm in various field plots between 1991 and 1999. The farm had seen populations of one to 2.5 million beetles per acre and the Pecks had lost entire crops of alfalfa with a resulting decrease in milk production and increased production costs caused by the need to purchase protein supplement and seed to replant alfalfa fields.

The fall 2005 survey for ASB showed an absence of larval feeding damage to alfalfa roots on the farm and more alfalfa than the Peck family had seen since ASB invaded the farm in 1985.

John D. Peck says, �A few years ago I saw this strange looking root sticking out of our plowed alfalfa fields. I asked my dad what it was and he told me they were alfalfa tap roots. This year will be my twentieth year working on the farm and until about four years ago I had never seen an alfalfa tap root because of the snout beetles.

�These bugs are a major nuisance and have cost us a lot of money over the years,� Peck says. �Our cows milked well on grass fields and grass hay, but now they have transitioned to the richer alfalfa forage once again since the decline in the snout beetle population. We are very thankful and encouraged by the Northern New York Agricultural Development Program-funded research that Cornell University has conducted here.�

He believes the nematodes will be the best method for controlling ASB in areas already infected with the insect and that the ASB-resistant alfalfa hybrid breeding will be more beneficial to areas that are at risk for infestation, but have not had a major outbreak such as in Northern New York.

Shields says, �The frequency of nematodes in the soil samples from the Peck farm in 2006 is similar to the frequency seen in soil samples from the parts of Hungary where the alfalfa snout beetle is not easily found and is not considered a crop pest.�

Now that the nematodes have shown their potential to reduce ASB populations in infested areas, Shields is working to develop an effective and easily implemented method for farmers to inoculate their alfalfa fields with the biological control organism. Shields believes that field trials in 2006 were sabotaged by mice, shrews and skunks which ate the inoculation medium that contained the nematodes. An array of other inoculation techniques are being field tested in 2007.

Farmers often do not realize they have the pest, because crop loss to ASB mimics winterkill with the majority of the alfalfa crop dying after the last harvest and before spring growth. Shields says although the ASB population has decreased on the Peck farm, neighboring farmers should be vigilant. Millions of the insect have been seen and collected within a mile of the Peck farm. ASB is also expanding its range in Ontario, Canada, with new discoveries as far north as Ottawa.

Farmers who suspect they have ASB should contact their local Cornell Cooperative Extension office.

For more information on the alfalfa snout beetle projects funded by the Northern New York Agricultural Development Program, a farmer-led research, education and outreach program, go online to www.nnyagdev.org.  # # #