PPMN Weekly Update May 27-31, 2013
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Prairie Pest Monitoring Network Weekly Updates – June 17-21, 2013 Weiss, Giffen, Olfert – AAFC Saskatoon & Otani – AAFC Beaverlodge 1. Weather synopsis – Here is an update for the weather conditions for our growing season. Below is the Accumulated Precipitation for the Growing Season across the prairies (i.e., April 1-June 20, 2013): Wow – what a week for rain…. Below is the Accumulated Precipitation the Past 7 Days (i.e., May 31-June 20, 2013): Now notice the change in the map below which reflects the Percent of Normal Accumulated Precipitation for the Growing Season (April 1-June 20, 2013): No indication that frost hit our field cropped acres across the prairies this past week. Instead, below find the map reflecting the Highest Temperatures the Past 7 Days (to Jun 20, 2013) across the prairies: Growing degree day (GDD) estimates reflect the growing season, in terms of heat accumulation, across the prairies. Below is the GDD (Base 5ºC) for the Growing Season (April 1-June 19, 2013): AAFC: Giffen et al. While below is the GDD (Base 10ºC) for the Growing Season (April 1-June 19, 2013): AAFC: Giffen et al. 2. Flea Beetles (Phyllotreta striolata and Phyl. cruciferae) – More reports of feeding damage in young stands of canola occurred this past week in Manitoba with foliar applications of insecticide and even a bit of reseeding required to manage the damage in the northwest and southwest regions. Producers in Saskatchewan were advised to monitor stands for flea beetles. 3. Cutworms (Noctuidae) – One last reminder to monitor for cutworms in June! Some species of cutworms should still be active as larvae in our prairie fields. Recent reports of cutworm activity came from all regions of Manitoba (courtesy of Manitoba Agriculture’s John Gavloski update of June 17th) where canola and sunflowers suffered damage. Refer to the table below for the species that remain as larvae by mid-June and scout. In- field monitoring remains critical for newly seeded stands. Scout for uneven emergence, missing rows, clipped stems, wilting or yellowing plants. Reminder: Little research has been done to develop economic threshold for cutworms in field crops on the Canadian prairies. Nominal thresholds, estimates based on experience rather than quantitative research, have been suggested for several field crops. These thresholds have been compiled by Manitoba Agriculture’s Dr. John Gavloski: CROP THRESHOLD Alfalfa 4-5 per square foot (new or thin stands - 2/sq ft.) Dry Beans 1 cutworm or more per metre of row and the larvae are still small (less than 2cm long) Canola A suggested nominal threshold is 25-30% stand reduction Corn When 3-6% of plants are cut and small larvae less than 1 inch present Flax 4-5 larvae/m2 Peas 2 to 3 cutworms per square metre Sunflowers 1 cutworm or more per square foot (30 by 30cm) or if there is a 25 to 30% stand reduction Wheat, Redbacked and army cutworms: 5-6/m2. Well established fall-seeded crops or Barley, spring seeded crops with good moisture conditions can tolerate higher numbers. Oats Table Source: Link to “Cutworms in Field Crops” (Manitoba Agriculture). Reminder: Here’s list of cutworm species and their respective lifecycle on the Canadian prairies: Egg Larva Pupa Adult WINTER SPRING SUMMER FALL Common name Species Larval feeding Oct-Mar Apr May Jun Jul Aug Sep Oct Redbacked Euxoa ochragaster (Gn.) Above-ground Darksided Euxoa messoria (Haw.) Above-ground Bristly Lacinipolia renigera (Steph.) Above-ground Army Euxoa auxiliaris Above-ground Dingy Feltia jaculifera (Gn.) Above-ground Dingy Feltia herilis (Grt.) Above-ground Dingy Feltia subgothica (Haw.) Above-ground Clover Discestra trifolii (Hufn.) Above-ground Spotted Xestia adela Franc. Above-ground Glassy Apamea devastator (Brace) Subterranean Yellow-headed Apamea amputatrix Above-ground Yellow-headed Apamea inficita Above-ground Yellow-headed Apamea cogitata Above-ground Pale western Agrotis orthogonia Morrison Subterranean Bronze Nephelodes minians Gn. Above-ground Dusky Agrotis venerabilis Wlk. Above-ground Armyworm Pseudaletia unipuncta (Haw.) Above-ground Cutworm biology, species information, plus monitoring recommendations can be viewed by clicking here to access the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol. Also refer to your provincial agricultural website for more information. Excellent cutworm photos are located within Manitoba Agriculture’s “Cutworms in Field Crops” fact sheet. And one last plea for help!!! Cutworm larvae are needed this spring for research – dead or alive. Refer to this website for detailed collecting information. Most importantly, please help the following researchers if you are finding cutworm infestations in your region: In Northern Alberta + B.C. Peace In Central Alberta In Southern Alberta Attn: Jennifer OTANI Attn: Jim BROATCH or Patty REID Attn: Jeremy HUMMEL #1 Research Station Road Lacombe Research Centre 4101 - 22 Ave South Beaverlodge Research Farm 6000 C & E Trail Lethbridge, AB T1K 4Y3 Agriculture & Agri-Food Canada Lacombe, AB T4L 1W1 Tel. 403-320-3202 ext.534 Beaverlodge AB T0H 0C0 Tel. 403-396-2535 [email protected] Tel. 780-354-5132 [email protected] [email protected] In Saskatchewan: In Manitoba: Drop samples off or send priority mail to: Drop samples off or send priority mail to: Attn: Scott HARTLEY Attn: Barb SHARONOWSKI Cutworm survey University of Manitoba Crop Protection Lab Dept. of Entomology Saskatchewan Ministry of Agriculture 12 Dafoe Road 346 MacDonald St. University of Manitoba Regina, SK S4N 6P6 Winnipeg, MB R3T 2N2 Tel. 306-787-8130 Tel. 204-474-7485 If cutworms are spotted in Albertan fields, please considering using the Alberta Pest Surveillance Network’s “2013 Cutworm Reporting Tool” for online reporting located at http://www1.agric.gov.ab.ca/$Department/pestmon.nsf/CutwormWebSubmission Data entered at this website uploads to a live “Cutworm Map” located at http://www.agric.gov.ab.ca/app68/listings/cutworm/cutworm_map.jsp which reflects cutworm sightings, associated species, plus host crop information. The most recent map is below as an example: 4. Wind trajectories Related to Diamondback Moth (DBM) and Aster Leafhopper Introductions – Sorry, wind trajectory summaries are not available this week due to staff performing field surveying. 5. Diamondback Moth (Plutella xylostella) – In Manitoba, DBM counts remained low this past week with the highest counts present in the eastern parts of the Central region. In Saskatchewan (courtesy of Scott Hartley), DBM were initially observed in late May but numbers remain low with only seven of the 27 traps intercepting moths. The highest DBM counts (i.e., <20 moths to date) occurred in the Regina/Belle Plaine area so far this year. Pheromone trapping for DBM in Alberta drew to a close last week. Based on pheromone traps, DBM numbers remain relatively low yet in-field monitoring remains critical particularly in young stands of canola that have small true leaves. Reminder: A few monitoring tips include: DBM larvae feeding damage will include window-pane feeding on leaves and larvae should be present regardless of time of day or temperature. Look also for a single green larva suspended from a single, silken thread – DBM larvae will drop off a plant using this silken thread if they are disturbed. As canola continues to leaf out into more mature rosette stages, consider pulling plants and tapping them out over a white sheet or end-gate to look for DBM larvae falling from the plants. Watch for the characteristic kicking response of DBM larvae in addition to the lime-green colour. Larva (12mm Pupa (10mm long) with long) is green prolegs at turning to tan posterior form and forms “V” and body within a generally delicate mesh tapered at cocoon head and adhered to posterior. plant. 6. Pea Leaf Weevil (Sitona lineatus) – Review the Pea Leaf Weevil Monitoring Protocol by clicking here to find biological and monitoring information for this pest on the prairies. Courtesy of Saskatchewan Agriculture’s Scott Hartley: Various levels of PLW damage were observed in southwest Saskatchewan during the 2013 survey. “Feeding notches were noted in a couple fields just north of the South Saskatchewan River and the weevil continues to affect fields further east than previously recorded. In 2013, significant infestations were observed in Rural Municipalities 76, 78, 109, 135, 141, 142, 166, and 167”. Reminder: Host plants for the pea leaf weevil include several species of Leguminaceae. Economic damage has been observed in peas, and faba beans. 7. Cereal Leaf Beetles (Oulema melanopus) – As of June 16, 2013, the model output predicts that the prairie CLB population is in either the egg or larval stages; no pupation has occurred. The model map below indicates that the population is primarily in the larval stage (85% compared to 20% last week) with populations in eastern Saskatchewan and much of Manitoba being slower to develop (i.e., eggs predicted to be present). O. melanopus % of Population in the Larval Stage June 16, 2013 AAFC: Weiss et al. The following graph represents modeled CLB development for Lethbridge AB. Larvae are predicted to be present until the first week of July. This has been confirmed by Meers & Barkley plus in-field monitoring performed by Carcamo et al. who reported relatively low densities of CLB larvae (second instar and larger) in fields near Warner and Vauxhall AB the week of June 21st. Their reported maximum density of 2-3 larvae per 10 stems (well below the threshold) was observed near Vauxhall. AAFC: Weiss et al. 8. Grasshopper Simulation Model Output - Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper). The simulation model is developed from grasshopper data collected on the Canadian prairies the past 60 years. As of June 16, 2013, model runs indicate that approximately 54% (compared to 30% last week) of the grasshopper population has hatched with the majority of these grasshoppers being in the first or second instar (13% were predicted to be in the third or fourth instar stages).