Late Breaking news!
2009 season
July 31, 2009 - Surveys of the region were conducted during the week of July 22. Plant samples collected from commercial fields were subjected to ELISA for detection of PEMV and BLRV. In addition, fields were surveyed for occurrence of virus symptoms. These data have been mapped and posted to this web site. In summary, BLRV and PEMV are detectable using ELISA, with a greater proportion of sites positive for virus in the southern part of the region than in the northern part. BLRV occurs throughout the region, while PEMV only in the southern part. Virus symptoms occur in more fields and in greater proportions of plants in fields in the southern part of the region. See the maps Virus symptoms, 2009 and Virus detection, 2009.
July 28, 2009 - A special workshop on virus symptoms in pea was held at the UI Plant Science Farm. An experiment under way there allowed participants to view pea plants with a range of symptoms caused by PEMV and BLRV. Plants had been inoculated for various periods of time in the field with both of these viruses.
July 22, 2009 - Virus disease symptoms typical for PEMV have been observed in fields as far north as Oaksdale. In the northern sections, however, the incidence within field is low and many fields appear to be symptom free north of Palouse WA. In some fields to the south the proportion of infected plants can exceed 20%. We are continuing to monitor the situation and are working to confirm PEMV as the causal agent. Although some reports of injury in garbanzo beans have been received, on inspection it is not clear these are caused by virus. This is being studied.
July 18, 2009 - Virus disease symptoms, sometimes severe and prevalent are now being observed in peas and garbanzo beans in the southern part of the region. Prevalence and severity are high enough in some fields to potentially cause yield losses. Review of samples from early in the season is underway, but preliminary results indicate few trapped aphids were carrying the virus.
July 15, 2009 - Virus disease symptoms have been observed in several fields in the southern part of the Palouse. We are collecting tissue from fields throughout the region and will be reporting results to this site within a few days.
July 10, 2009 - Virus disease symptoms and positive identification of presence of PEMV (by PCR) have been observed in one pea field near Almota WA. The crop is nearing maturity but symptoms including enations on foliage and distortions on pods are evident. Please stay tuned for additional information about this location and others during the next two days.
July 4, 2009 - Aphid numbers continue to be moderate with negligible occurrence of virus in immigrating winged aphids. Disease symptoms have not been observed in the crops. During the coming week we will be collecting plant tissue from pea and lentil fields to assess presence of virus.
June 19, 2009 - Aphid numbers collected in traps and encountered in pea fields are greater this year than in 2007 and 2008, but still relatively low. The early build up in May was depressed, evidently by the cool and wet weather in early June. We have only detected virus at one site thus far. That site appears to have BLRV and PEMV in the aphids collected. No disease symptoms are apparent in any sampled fields this year.
June 3, 2009 - Presentation. Sanford will make a short report on this season's aphids to the SPRING CROP INSECT UPDATE, hosted by Larry Smith in Lewiston ID (AM - Brammer Building 1225 Idaho Street).
May 30, 2009 - Trap sites have been set for 2009. Data on aphids collected from May 19 through May 26 have been posted as maps to the 2009 "movie". In summary, numbers of aphids trapped are greater than in the prior two years; more aphids are being collected from southern locations at this stage in the season. PCR tests have not detected virus in any incoming aphids this season.
May 6, 2009 - Traps in the basin. (Walla Walla, Touchet) for the week of April 20, these traps were free of pea aphids.
May 4, 2009 - Traps in the Palouse region. We have begun to set traps in the Palouse for the 2009 season. Although only a few growers have been able to plant pea or lentil, we will begin collecting aphids on May 15, as in prior years. We will have approximately 35 sites and these will be located on the map soon. Thanks to Ken Fuchs (CoAg) and Mike Devoe (Genesee Union) for their help in locating the trap sites this year.
April 30, 2009 - Columbia Basin. We made our annual foray into the Basin on April 17-19 this year. Despite the cool season, aphids were located in alfalfa in 13 of 27 sites surveyed. Abundance was low (about 0.1 aphids per sweep). Thanks to help from McGregor's field men, especially Marshall McKinleye we located traps in Walla Walla, Touchet and Dayton.
Feb. 24, 2009 - Traps. We are just beginning to determine positions for traps for this season. With the new funding, we will be placing more traps than in previous years. If you are interested in having a trap located near one of your fields, please contact us.
Feb. 23, 2009 - No pea aphids are detectable in the region. Alfalfa fields in the Columbia Basin are dormant. Inspections are just beginning this week to determine status of overwintering aphids near Prosser.
2008 Season
Sep 2008 - - The season continued to be a low aphid year. There was no evidence of virus disease or presence of viru.ses in the 30 field sites the team sampled in July.
July 20, 2008 - Pea aphid counts began to increase in late June, but overall remained low. Sampling is being concluded this week and traps will be removed. Virus incidence in aphids has been extremely low. Virus symptoms have not been observed in sampled fields. A few plants appear symptomatic in Spillman Research Farm this week, and these will be tested for virus this week. Overall, based on these data, risk of virus disease in the Palouse appears to be virtually nil.
June 23, 2008 - Pea aphid counts are rising slowly in the traps. The very first aphid to test positive for virus (PEMV) occurred in the Albion area in the 16 June sample. /font>
June 17, 2008 - Pea aphids are increasing slightly, to about 3-4 per sweep in many locations. Virus has been detected in two aphids collected from alfalfa fields in the Palouse, but so far not in any pea fields sampled.
June 15, 2008 - Pea aphids remain at very low levels in the traps (see This Year 2008 Locations). We have yet to detect virus in any trapped aphids. We have detected PEMV in just one aphid collected from alfalfa. Based on the similarities in aphid and virus incidence this year and last, it appears that 2008 will be very low risk of virus in pea and lentil on the Palouse. We plan to continue monitoring aphids in the traps and in the fields until the second week of July. Data will be updated as we do so. Happy fathers day!
June 5, 2008 - Pea aphids are beginning to arrive in the trap network (see This Year 2008 Locations). The numbers per trap are about 1/2 of what they were at this date in 2007, due evidently to the continuing cool and wet weather in the region. So far we have not detected virus in any of the aphids collected. Sweep net samples at 25 sites (all those shown on the Locations map), have collected no or few aphids at many sites. Maximum numbers observed are 1 aphid per sweep.
June 1, 2008 - The project will receive a boost in the form of a generous grant from the USDA-CSREES RAMP (Risk Assessment and Mediation Program). This grant will arrive in the fall of 2008 and allow us to continue to develop the risk forecasting system. It also includes funding to improve aphid management decision making, assess methods for pea aphid control and accelerate breeding efforts to provide virus-resistant varieties for the Palouse and elsewhere. A full description of the objectives of this proposal is forthcoming. We will be holding meetings with producers to seek input and report on the activities of this project.