Canola Watch Report No. 13
July 29, 2009
In This Issue
Warm and Dry
Hail Reported Again
Canola Flowering – Time to Evaluate Sclerotina Risk
How to Apply a Fungicide with Variable Stages
Insects Found – Still Monitoring
Opportunity to Support Canola Research
Bud Bouqueting – Thrips to Blame? Send Samples for ID
Affected Patches Appearing – Find out Why
Harvest Approaching – Start Planning Now
Keep Malathion OUT of Canola Bins
Questions & Contacts
This report is supported by each of the provincial canola grower associations. For more information on some of their activities check out the following links:
The Alberta Canola Producers Commission (ACPC) has developed an e-newsletter called Alberta Canola Connections. Sign up today http://www.canola.ab.ca/newsletter.html to receive the latest information on agronomy, marketing, coming events and more, or check out their website at http://www.canola.ab.ca/.
In Manitoba sign up for the Manitoba Canola Growers Association newsletter at Canola Growers E-update by visiting their website located at http://www.mcgacanola.org/
For information on activities in Saskatchewan, visit SaskCanola at http://www.saskcanola.com/.
Warm and Dry
Relatively warm temperatures occurred across much of western Canada last week with very little precipitation. Much of the Prairies are dry and require additional moisture soon with the exception of the eastern and Interlake regions of Manitoba, which continue to be wet in many areas. In areas with inadequate soil moisture, the relatively high temperatures are beginning to stress much of the canola crop. Heat stress (wilting) and flower blasting have been observed in many areas across the Prairies. Although crop development was accelerated with recent warm conditions, most areas continue to report crop maturity about one to two weeks later than normal. Flower blasting is undesirable because yield will be impacted. However, the trade-off is that a termination to flowering hastens maturity. Earliest seeded canola fields are at the 50% bloom to fully podded stage and re-seeded fields are bolting to early flower.
Maps of current moisture conditions in western Canada from PFRA are available at:
http://www.agr.gc.ca/pfra/drought/prpay09_e.htm
http://www.agr.gc.ca/pfra/drought/prpgs09_e.htm
Additional moisture information for Alberta is available from Alberta Environment at:
http://www.environment.alberta.ca/forecasting/data/precipmaps/weekly.pdf
The latest crop report from Manitoba Agriculture, Food & Rural Initiatives is available at: http://web2.gov.mb.ca/agriculture/mwcr/index.php
The latest crop report from Saskatchewan Ministry of Agriculture is available at: http://www.agriculture.gov.sk.ca/crprpt090723
The latest crop report from Alberta Agriculture and Rural Development is available at:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/sdd4191#2009
The following maps show growing degree days accumulating across western Canada this growing season: http://www.agr.gc.ca/pfra/drought/prtgdd_e.htm
to the top
Hail Reported Again
Thunderstorms last week and over the weekend brought hail to a number of locations again. Mid-season hail damage not only causes physical injury on the plant but is also a concern for disease access. The hail wounds on the plant can provide points of entry for disease pathogens such as sclerotinia stem rot, alternaria black spot or blackleg if environmental conditions have been conducive to spore production and disease development. If growers are contemplating a fungicide application, they may also consider yield potential of the remaining crop and the risk of fall frost due to the delayed maturity, which could negate the benefits of the application. More information about hail damage to canola is available at the following link: http://www.canola-council.org/chapter5.aspx.
to the top
Canola Flowering – Time to Evaluate Sclerotina Risk
Late-seeded and re-seeded canola fields are beginning to flower. These fields should now be assessed for risk to sclerotinia stem rot infection to determine if a fungicide application will be economical. Remember, many factors affect the risk of infection including:
Heaviness of the crop canopy
Amount of moisture received in the two weeks prior to flowering and potential for further rainfall
Years since last host crop
Disease incidence in the past
Presence of apothecia in neighboring fields
Thin stands which result in a light, open canopy will likely help lower risk in a number of locations this year. However, regular precipitation and high humidity at early flowering can still lead to significant disease development in thin stands, especially if plants begin to lodge.
The link https://canola-council.merchantsecure.com/canola_resources/product11.aspx is a "Canola Disease Scouting and Risk Assessment Card" which can help with risk assessment: This card will help determine if fungicide applications are warranted, particularly where yield potential is reduced by late maturity or low plant numbers.
Alberta Canola Producers Commission has an audio discussion on scouting for sclerotinia and making fungicide decisions with Dr. Kelly Turkington, Agriculture and Agri-Food Canada at the following link: http://www.canola.ab.ca/.
to the top
How to Apply a Fungicide with Variable Stages
This year has certainly been challenging for canola production and as a result, crop staging is wide ranging in some fields. Should a fungicide be applied now when the oldest plants flower or later with the later-flowering plants? Each field should be assessed individually for risk of infection from sclerotinia stem rot. A few things to keep in mind:
Thin plant stands are more open and will dry out more readily during the day. Infection risk will be lower unless regular showers or high relative humidity with heavy dews keep the canopy damp.
Recent rains do not necessarily mean increased risk of infection. Sclerotia require good soil moisture (one to two inches of rain in one to two week period) to germinate into apothecia and produce spores for infection. Surface soil moisture has certainly been limited recently in many parts of western Manitoba, southwestern Saskatchewan and Alberta. With recent rains it may take about a week for sclerotia to germinate into apothecia and release spores that cause infection. Canola staging may advance enough that this late release of spores is too late to cause significant disease development in earlier maturing fields.
Scout for apothecia (small golf tee shaped mushrooms that produce the spores) in fields where susceptible crops, such as canola, pulses and sunflowers were grown last year. The more you find the greater the potential for spore production.
Generally, earliest infections cause the greatest yield loss. If one application is being made, scout fields well to determine when the majority of plants (that are the biggest yield contributors) are at the appropriate stage for fungicide application.
If the crop staging (and ultimately flowering) is variable, consider a split application. The first application can be made when the first plants reach recommended staging. If necessary, a second application can be made when the remaining plants are ready to be sprayed. In Manitoba, fungicides are being sprayed on portions of a field because of the variable staging. This too may be an option. Refer to current crop protection guides to determine which products are registered for split application and recommended rates of application: http://www.gov.mb.ca/agriculture/crops/cropproduction/gaa01d01.html
Consider the lateness of the season and frost-free days remaining. Be realistic with yield goals. If the crop is flowering late, is there enough time to gain a return on the fungicide investment?
Bayer Weather Command Centre produces a risk map daily for sclerotinia infection based on weather data (temperature and relative humidity) collected from Weatherbug stations located throughout western Canada. If interested in viewing the risk map, visit the following link http://www.bayerweather.ca/ and login into the site with Canola as the ‘username’ and Grower as the ‘password’. Please take note that the login information must be typed with capital and lower case letters exactly as shown. The sclerotinia risk map is located under the risk analysis tab. Access to this site will be for a limited time only, so anyone interested in long term access can email askus@bayercropscience.com.
The following link has good photos of a canola field progressing through flowering stages (10% to full bloom): http://www.ag.ndsu.edu/pubs/plantsci/crops/pp1410.pdf
to the top
Insects Found – Still Monitoring
Bertha armyworm traps continue to be used for monitoring but so far numbers caught in Manitoba and Alberta indicate the risk is low. However, trap numbers in a few locations in Saskatchewan have surpassed the low threshold and fields in these areas may need to be watched more closely in the coming weeks. A risk map based on trap counts in Saskatchewan is available at the following link: http://www.agriculture.gov.sk.ca/Default.aspx?DN=e7788ad2-6b94-492a-95aa-3c7af80975aa. The map will be updated regularly as trap results come in.
Cabbage root maggots were again reported in Saskatchewan and Alberta. A number of fields in Alberta had considerable damage. Drier conditions earlier this spring are generally not favorable for root maggots so it is a bit surprising to see significant damage. There are only cultural management tools for this insect pest. More information on cabbage maggot is available at: http://www.gov.mb.ca/agriculture/crops/insects/fad04s00.html. An audio discussion on root maggots and other insect pests with Dr. Lloyd Dosdall, University of Alberta is available at ACPC’s website http://www.canola.ab.ca/.
Lygus populations are being monitored in the Peace Region of Alberta where populations have exceeded economic thresholds in the Rolla and Spirit River areas. There is a range for the economic threshold depending on crop stage and price. More information is available at the following link: http://www.gov.mb.ca/agriculture/crops/insects/fad12s00.html
Grasshopper activity increased with recent warm conditions and many areas report spraying of pastures and hayfields. Grasshoppers may become a concern in canola adjacent to a field cut for hay as the insects migrate to continue feeding. Continue scouting for grasshoppers because if caught early perimeter spraying may be all that is needed. A specific economic threshold for grasshoppers in canola has not been established as it is not a preferred host crop, but it is currently considered to be in the range of 7 to 14 per m2, depending on the crop value and cost for control. More information on grasshoppers is available at the following link: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex6463
to the top
Opportunity to Support Canola Research
Dan Johnson at the University of Lethbridge is looking for cooperators to participate in field research for a bio-pesticide for grasshopper control in canola. Information on the pesticide is available at the following link:http://people.uleth.ca/~dan.johnson/metar.htm. A field test would generally fit into 25 acres of infested crop. Growers with grasshoppers in canola who are interested in participating can contact Dan Johnson at dan.johnson@uleth.ca or Morgan Guo at mengjuan.guo@uleth.ca.
to the top
Bud Bouqueting – Thrips to Blame? Send Samples for ID
Reports continued this past week of bud bouqueting -- where flower clusters develop in the centre of the rosette without bolting -- from fields in southern, central and Peace Region of Alberta. The internodes on the primary branch are shortened and, as a result, the buds appear within the centre of the rosette. A number of factors can cause shortened internodes (e.g. environmental stress, chemical damage, insects such as thrips). If growers notice bud bouqueting, the following scouting tips may help discover the cause:
Scout the field thoroughly. Pay close attention along the field edge and corners where the sprayer boom may have swung wide, as this may have resulted in an untreated area. If the symptoms do not appear in the unsprayed area, then perhaps chemical damage is playing a role.
Pull plants and examine the root system. Perhaps there is something below the soil surface that is causing the symptoms.
Make note of any pattern of affected plants within the field. Are low areas more affected than knolls or vice versa? This can often help determine if symptoms are temperature related.
Thrips were believed to be the cause of symptoms in one field near Morinville, Alberta. To scout for thrips pull complete plants and using a piece of paper (often useful to use a white and a colored piece) bang the plants gently on the paper on a hard surface to dislodge any insects that may be hiding within the buds. Thrips are very small (adults 1 mm in length) so a magnifying glass may help. If thrips are found, it is important to have a positive species identification made because some species (e.g. pollen feeders) have been found to increase pollination and others have resulted in yield reductions (feeding during bud stage).
Ken Fry at Olds College will accept insect samples for thrip species identification. Insect samples can be obtained by banging a flower cluster inside a plastic cup and then emptying the contents into a leak-proof vial with a suitable preservative (rubbing or isopropyl alcohol, RV anti-freeze, ethanol). Send these labeled vials in a crush proof package to: Ken Fry, Olds College, 4500-50th Street, Olds, AB T4H 1R6
Anyone noticing symptoms of bud bouqueting can also contact their regional agronomist (contact information below) for further assistance.
A photo of a thrip is available at the Canola Council of Canada’s photo gallery at the following link: http://www.canola-council.org/gallery/855/pests_insects.aspx.
More information on thrips can be found in this ornamental factsheet from BC Ministry of Agriculture, Food and Fisheries: http://www.agf.gov.bc.ca/ornamentals/publications/pesticide/insect/THRIPS.pdf
to the top
Affected Patches Appearing – Find out Why
At this time of year as the canola crop finishes flowering and begins to pod, stressed or affected patches often appear within the field. These patches are often most noticeable because they come out of flower sooner than the rest of the field. This is a good opportunity to scout and to determine what is happening with the canola crop. Are these stressed patches located on knolls (e.g. lacking moisture sooner or could soil fertility be playing a role)? Are root maggots present? Pull plants with roots intact and check for root maggots. Plant disease symptoms can also begin to appear at this time so take a closer look to determine if blackleg or sclerotinia stem rot are present. Clubroot disease may be another potential explanation. In the first few Canola Watch issues this spring, it was reported that a soil test from west-central Saskatchewan had shown the potential presence of the clubroot pathogen’s DNA. Further testing was being conducted to confirm the results. This past week, SaskCanola, reported that the DNA diagnostic test and a canola plant bioassay confirmed that trace levels of the clubroot pathogen (Plasmodiophora brassicae) were present in that soil sample. More information is found in the press release issued at: http://www.saskcanola.com/news/2009-0721-clubroot.html
While scouting, it is important to follow field entry protocols to maintain proper sanitation and limit the spread of clubroot. More information on sanitation guidelines is available at the following link: http://www.canolacouncil.org/clubroot/docs/field_entry_1.pdf and more general information on clubroot is available at http://www.clubroot.ca/
to the top
Harvest Approaching – Start Planning Now
If warm, dry conditions continue, cutting of the earliest canola fields may begin within three to four weeks. After flowering (pod filling), is a good time to assess yield potential leading up to harvest. The variable staging this year has not evened out and will require more management at harvest. It may be beneficial to mark or section off fields based on similar staging and yield potential. Know where the greatest yield potential is within the field and plan to focus on protecting it the most. The greatest yield potential includes the plants with most seeds but also earliest maturing to escape a fall frost. Yield potential can be assessed by counting the number of pods on a plant, and determining the number of seeds per pod. Pods can be plucked and held up to the light to determine the number of seeds within the pod. While scouting, think about the approach needed for harvest. Is the staging so variable that a desiccant may be needed to hasten maturity on the latest plants? Would swathing be better than straight cutting or vice versa? Is there a lot of green weed growth that will require a pre-harvest application?
to the top
Keep Malathion OUT of Canola Bins
As bins are prepared for the coming harvest, keep in mind that using malathion on canola seed or in canola storage bins will result in detectable levels of malathion residue because malathion has a strong attraction to the oil in canola seed. Consequently, malathion can move into canola seed from storage bin walls. Detection of malathion residue in canola seed above the allowable limit will result in rejected shipments and increased monitoring. DO NOT use malathion to treat bins destined to store canola. More information is available at the following link: http://www.canola-council.org/pesticide_link2.aspx
to the top
Questions & Contacts
Direct questions regarding this report to John Mayko, Senior Agronomy Specialist with the Canola Council of Canada at maykoj@canolacouncil.org, 780-764-2593.
Direct specific questions regarding regional issues to one of the following Canola Council of Canada regional agronomists or provincial oilseed specialists:
Derwyn Hammond, Senior Agronomy Specialist Manitoba, hammondd@canolacouncil.org, 204-729-9011
Anastasia Kubinec, Manitoba Agriculture, Food and Rural Initiatives, anastasia.kubinec@gov.mb.ca, 204-745-5645
Jim Bessel, Senior Agronomy Specialist, Central Saskatchewan, besselj@canolacouncil.org, 306-373-6771
Tiffany Martinka, Agronomy Specialist, Eastern Saskatchewan, martinkat@canolacouncil.org, 306-231-3663
Venkata Vakulabharanam, Saskatchewan Ministry of Agriculture, Venkata.Vakulabharanam@gov.sk.ca, (306)787-4668
Doug Moisey, Senior Agronomy Specialist, East Central Alberta and Northwestern Saskatchewan, moiseyd@canolacouncil.org, 780-645-9205
Erin Brock, Agronomy Specialist, Peace Region, brocke@canolacouncil.org,
780-568-3326
Murray Hartman, Alberta Agriculture and Rural Development, murray.hartman@gov.ab.ca, 403-782-8024
Kerry Clark, BC Ministry of Agriculture and Lands, Kerry.Clark@gov.bc.ca, 250-784-2559
The Canola Watch Report provides just-in-time information on canola production to growers and industry. Contributors to the Canola Agronomy Network are:
Alberta Canola Producers Commission; Alberta Agriculture and Rural Development, SaskCanola, Saskatchewan Canola Growers Association, Saskatchewan Ministry of Agriculture, Manitoba Canola Growers Association, Manitoba Agriculture, Food and Rural Initiatives, Peace River Agriculture Development Fund, B.C. Ministry of Agriculture & Lands, Agriculture and Agri-Food Canada, and the Canola Council of Canada.
July 29, 2009
In This Issue
Warm and Dry
Hail Reported Again
Canola Flowering – Time to Evaluate Sclerotina Risk
How to Apply a Fungicide with Variable Stages
Insects Found – Still Monitoring
Opportunity to Support Canola Research
Bud Bouqueting – Thrips to Blame? Send Samples for ID
Affected Patches Appearing – Find out Why
Harvest Approaching – Start Planning Now
Keep Malathion OUT of Canola Bins
Questions & Contacts
This report is supported by each of the provincial canola grower associations. For more information on some of their activities check out the following links:
The Alberta Canola Producers Commission (ACPC) has developed an e-newsletter called Alberta Canola Connections. Sign up today http://www.canola.ab.ca/newsletter.html to receive the latest information on agronomy, marketing, coming events and more, or check out their website at http://www.canola.ab.ca/.
In Manitoba sign up for the Manitoba Canola Growers Association newsletter at Canola Growers E-update by visiting their website located at http://www.mcgacanola.org/
For information on activities in Saskatchewan, visit SaskCanola at http://www.saskcanola.com/.
Warm and Dry
Relatively warm temperatures occurred across much of western Canada last week with very little precipitation. Much of the Prairies are dry and require additional moisture soon with the exception of the eastern and Interlake regions of Manitoba, which continue to be wet in many areas. In areas with inadequate soil moisture, the relatively high temperatures are beginning to stress much of the canola crop. Heat stress (wilting) and flower blasting have been observed in many areas across the Prairies. Although crop development was accelerated with recent warm conditions, most areas continue to report crop maturity about one to two weeks later than normal. Flower blasting is undesirable because yield will be impacted. However, the trade-off is that a termination to flowering hastens maturity. Earliest seeded canola fields are at the 50% bloom to fully podded stage and re-seeded fields are bolting to early flower.
Maps of current moisture conditions in western Canada from PFRA are available at:
http://www.agr.gc.ca/pfra/drought/prpay09_e.htm
http://www.agr.gc.ca/pfra/drought/prpgs09_e.htm
Additional moisture information for Alberta is available from Alberta Environment at:
http://www.environment.alberta.ca/forecasting/data/precipmaps/weekly.pdf
The latest crop report from Manitoba Agriculture, Food & Rural Initiatives is available at: http://web2.gov.mb.ca/agriculture/mwcr/index.php
The latest crop report from Saskatchewan Ministry of Agriculture is available at: http://www.agriculture.gov.sk.ca/crprpt090723
The latest crop report from Alberta Agriculture and Rural Development is available at:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/sdd4191#2009
The following maps show growing degree days accumulating across western Canada this growing season: http://www.agr.gc.ca/pfra/drought/prtgdd_e.htm
to the top
Hail Reported Again
Thunderstorms last week and over the weekend brought hail to a number of locations again. Mid-season hail damage not only causes physical injury on the plant but is also a concern for disease access. The hail wounds on the plant can provide points of entry for disease pathogens such as sclerotinia stem rot, alternaria black spot or blackleg if environmental conditions have been conducive to spore production and disease development. If growers are contemplating a fungicide application, they may also consider yield potential of the remaining crop and the risk of fall frost due to the delayed maturity, which could negate the benefits of the application. More information about hail damage to canola is available at the following link: http://www.canola-council.org/chapter5.aspx.
to the top
Canola Flowering – Time to Evaluate Sclerotina Risk
Late-seeded and re-seeded canola fields are beginning to flower. These fields should now be assessed for risk to sclerotinia stem rot infection to determine if a fungicide application will be economical. Remember, many factors affect the risk of infection including:
Heaviness of the crop canopy
Amount of moisture received in the two weeks prior to flowering and potential for further rainfall
Years since last host crop
Disease incidence in the past
Presence of apothecia in neighboring fields
Thin stands which result in a light, open canopy will likely help lower risk in a number of locations this year. However, regular precipitation and high humidity at early flowering can still lead to significant disease development in thin stands, especially if plants begin to lodge.
The link https://canola-council.merchantsecure.com/canola_resources/product11.aspx is a "Canola Disease Scouting and Risk Assessment Card" which can help with risk assessment: This card will help determine if fungicide applications are warranted, particularly where yield potential is reduced by late maturity or low plant numbers.
Alberta Canola Producers Commission has an audio discussion on scouting for sclerotinia and making fungicide decisions with Dr. Kelly Turkington, Agriculture and Agri-Food Canada at the following link: http://www.canola.ab.ca/.
to the top
How to Apply a Fungicide with Variable Stages
This year has certainly been challenging for canola production and as a result, crop staging is wide ranging in some fields. Should a fungicide be applied now when the oldest plants flower or later with the later-flowering plants? Each field should be assessed individually for risk of infection from sclerotinia stem rot. A few things to keep in mind:
Thin plant stands are more open and will dry out more readily during the day. Infection risk will be lower unless regular showers or high relative humidity with heavy dews keep the canopy damp.
Recent rains do not necessarily mean increased risk of infection. Sclerotia require good soil moisture (one to two inches of rain in one to two week period) to germinate into apothecia and produce spores for infection. Surface soil moisture has certainly been limited recently in many parts of western Manitoba, southwestern Saskatchewan and Alberta. With recent rains it may take about a week for sclerotia to germinate into apothecia and release spores that cause infection. Canola staging may advance enough that this late release of spores is too late to cause significant disease development in earlier maturing fields.
Scout for apothecia (small golf tee shaped mushrooms that produce the spores) in fields where susceptible crops, such as canola, pulses and sunflowers were grown last year. The more you find the greater the potential for spore production.
Generally, earliest infections cause the greatest yield loss. If one application is being made, scout fields well to determine when the majority of plants (that are the biggest yield contributors) are at the appropriate stage for fungicide application.
If the crop staging (and ultimately flowering) is variable, consider a split application. The first application can be made when the first plants reach recommended staging. If necessary, a second application can be made when the remaining plants are ready to be sprayed. In Manitoba, fungicides are being sprayed on portions of a field because of the variable staging. This too may be an option. Refer to current crop protection guides to determine which products are registered for split application and recommended rates of application: http://www.gov.mb.ca/agriculture/crops/cropproduction/gaa01d01.html
Consider the lateness of the season and frost-free days remaining. Be realistic with yield goals. If the crop is flowering late, is there enough time to gain a return on the fungicide investment?
Bayer Weather Command Centre produces a risk map daily for sclerotinia infection based on weather data (temperature and relative humidity) collected from Weatherbug stations located throughout western Canada. If interested in viewing the risk map, visit the following link http://www.bayerweather.ca/ and login into the site with Canola as the ‘username’ and Grower as the ‘password’. Please take note that the login information must be typed with capital and lower case letters exactly as shown. The sclerotinia risk map is located under the risk analysis tab. Access to this site will be for a limited time only, so anyone interested in long term access can email askus@bayercropscience.com.
The following link has good photos of a canola field progressing through flowering stages (10% to full bloom): http://www.ag.ndsu.edu/pubs/plantsci/crops/pp1410.pdf
to the top
Insects Found – Still Monitoring
Bertha armyworm traps continue to be used for monitoring but so far numbers caught in Manitoba and Alberta indicate the risk is low. However, trap numbers in a few locations in Saskatchewan have surpassed the low threshold and fields in these areas may need to be watched more closely in the coming weeks. A risk map based on trap counts in Saskatchewan is available at the following link: http://www.agriculture.gov.sk.ca/Default.aspx?DN=e7788ad2-6b94-492a-95aa-3c7af80975aa. The map will be updated regularly as trap results come in.
Cabbage root maggots were again reported in Saskatchewan and Alberta. A number of fields in Alberta had considerable damage. Drier conditions earlier this spring are generally not favorable for root maggots so it is a bit surprising to see significant damage. There are only cultural management tools for this insect pest. More information on cabbage maggot is available at: http://www.gov.mb.ca/agriculture/crops/insects/fad04s00.html. An audio discussion on root maggots and other insect pests with Dr. Lloyd Dosdall, University of Alberta is available at ACPC’s website http://www.canola.ab.ca/.
Lygus populations are being monitored in the Peace Region of Alberta where populations have exceeded economic thresholds in the Rolla and Spirit River areas. There is a range for the economic threshold depending on crop stage and price. More information is available at the following link: http://www.gov.mb.ca/agriculture/crops/insects/fad12s00.html
Grasshopper activity increased with recent warm conditions and many areas report spraying of pastures and hayfields. Grasshoppers may become a concern in canola adjacent to a field cut for hay as the insects migrate to continue feeding. Continue scouting for grasshoppers because if caught early perimeter spraying may be all that is needed. A specific economic threshold for grasshoppers in canola has not been established as it is not a preferred host crop, but it is currently considered to be in the range of 7 to 14 per m2, depending on the crop value and cost for control. More information on grasshoppers is available at the following link: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex6463
to the top
Opportunity to Support Canola Research
Dan Johnson at the University of Lethbridge is looking for cooperators to participate in field research for a bio-pesticide for grasshopper control in canola. Information on the pesticide is available at the following link:http://people.uleth.ca/~dan.johnson/metar.htm. A field test would generally fit into 25 acres of infested crop. Growers with grasshoppers in canola who are interested in participating can contact Dan Johnson at dan.johnson@uleth.ca or Morgan Guo at mengjuan.guo@uleth.ca.
to the top
Bud Bouqueting – Thrips to Blame? Send Samples for ID
Reports continued this past week of bud bouqueting -- where flower clusters develop in the centre of the rosette without bolting -- from fields in southern, central and Peace Region of Alberta. The internodes on the primary branch are shortened and, as a result, the buds appear within the centre of the rosette. A number of factors can cause shortened internodes (e.g. environmental stress, chemical damage, insects such as thrips). If growers notice bud bouqueting, the following scouting tips may help discover the cause:
Scout the field thoroughly. Pay close attention along the field edge and corners where the sprayer boom may have swung wide, as this may have resulted in an untreated area. If the symptoms do not appear in the unsprayed area, then perhaps chemical damage is playing a role.
Pull plants and examine the root system. Perhaps there is something below the soil surface that is causing the symptoms.
Make note of any pattern of affected plants within the field. Are low areas more affected than knolls or vice versa? This can often help determine if symptoms are temperature related.
Thrips were believed to be the cause of symptoms in one field near Morinville, Alberta. To scout for thrips pull complete plants and using a piece of paper (often useful to use a white and a colored piece) bang the plants gently on the paper on a hard surface to dislodge any insects that may be hiding within the buds. Thrips are very small (adults 1 mm in length) so a magnifying glass may help. If thrips are found, it is important to have a positive species identification made because some species (e.g. pollen feeders) have been found to increase pollination and others have resulted in yield reductions (feeding during bud stage).
Ken Fry at Olds College will accept insect samples for thrip species identification. Insect samples can be obtained by banging a flower cluster inside a plastic cup and then emptying the contents into a leak-proof vial with a suitable preservative (rubbing or isopropyl alcohol, RV anti-freeze, ethanol). Send these labeled vials in a crush proof package to: Ken Fry, Olds College, 4500-50th Street, Olds, AB T4H 1R6
Anyone noticing symptoms of bud bouqueting can also contact their regional agronomist (contact information below) for further assistance.
A photo of a thrip is available at the Canola Council of Canada’s photo gallery at the following link: http://www.canola-council.org/gallery/855/pests_insects.aspx.
More information on thrips can be found in this ornamental factsheet from BC Ministry of Agriculture, Food and Fisheries: http://www.agf.gov.bc.ca/ornamentals/publications/pesticide/insect/THRIPS.pdf
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Affected Patches Appearing – Find out Why
At this time of year as the canola crop finishes flowering and begins to pod, stressed or affected patches often appear within the field. These patches are often most noticeable because they come out of flower sooner than the rest of the field. This is a good opportunity to scout and to determine what is happening with the canola crop. Are these stressed patches located on knolls (e.g. lacking moisture sooner or could soil fertility be playing a role)? Are root maggots present? Pull plants with roots intact and check for root maggots. Plant disease symptoms can also begin to appear at this time so take a closer look to determine if blackleg or sclerotinia stem rot are present. Clubroot disease may be another potential explanation. In the first few Canola Watch issues this spring, it was reported that a soil test from west-central Saskatchewan had shown the potential presence of the clubroot pathogen’s DNA. Further testing was being conducted to confirm the results. This past week, SaskCanola, reported that the DNA diagnostic test and a canola plant bioassay confirmed that trace levels of the clubroot pathogen (Plasmodiophora brassicae) were present in that soil sample. More information is found in the press release issued at: http://www.saskcanola.com/news/2009-0721-clubroot.html
While scouting, it is important to follow field entry protocols to maintain proper sanitation and limit the spread of clubroot. More information on sanitation guidelines is available at the following link: http://www.canolacouncil.org/clubroot/docs/field_entry_1.pdf and more general information on clubroot is available at http://www.clubroot.ca/
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Harvest Approaching – Start Planning Now
If warm, dry conditions continue, cutting of the earliest canola fields may begin within three to four weeks. After flowering (pod filling), is a good time to assess yield potential leading up to harvest. The variable staging this year has not evened out and will require more management at harvest. It may be beneficial to mark or section off fields based on similar staging and yield potential. Know where the greatest yield potential is within the field and plan to focus on protecting it the most. The greatest yield potential includes the plants with most seeds but also earliest maturing to escape a fall frost. Yield potential can be assessed by counting the number of pods on a plant, and determining the number of seeds per pod. Pods can be plucked and held up to the light to determine the number of seeds within the pod. While scouting, think about the approach needed for harvest. Is the staging so variable that a desiccant may be needed to hasten maturity on the latest plants? Would swathing be better than straight cutting or vice versa? Is there a lot of green weed growth that will require a pre-harvest application?
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Keep Malathion OUT of Canola Bins
As bins are prepared for the coming harvest, keep in mind that using malathion on canola seed or in canola storage bins will result in detectable levels of malathion residue because malathion has a strong attraction to the oil in canola seed. Consequently, malathion can move into canola seed from storage bin walls. Detection of malathion residue in canola seed above the allowable limit will result in rejected shipments and increased monitoring. DO NOT use malathion to treat bins destined to store canola. More information is available at the following link: http://www.canola-council.org/pesticide_link2.aspx
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Questions & Contacts
Direct questions regarding this report to John Mayko, Senior Agronomy Specialist with the Canola Council of Canada at maykoj@canolacouncil.org, 780-764-2593.
Direct specific questions regarding regional issues to one of the following Canola Council of Canada regional agronomists or provincial oilseed specialists:
Derwyn Hammond, Senior Agronomy Specialist Manitoba, hammondd@canolacouncil.org, 204-729-9011
Anastasia Kubinec, Manitoba Agriculture, Food and Rural Initiatives, anastasia.kubinec@gov.mb.ca, 204-745-5645
Jim Bessel, Senior Agronomy Specialist, Central Saskatchewan, besselj@canolacouncil.org, 306-373-6771
Tiffany Martinka, Agronomy Specialist, Eastern Saskatchewan, martinkat@canolacouncil.org, 306-231-3663
Venkata Vakulabharanam, Saskatchewan Ministry of Agriculture, Venkata.Vakulabharanam@gov.sk.ca, (306)787-4668
Doug Moisey, Senior Agronomy Specialist, East Central Alberta and Northwestern Saskatchewan, moiseyd@canolacouncil.org, 780-645-9205
Erin Brock, Agronomy Specialist, Peace Region, brocke@canolacouncil.org,
780-568-3326
Murray Hartman, Alberta Agriculture and Rural Development, murray.hartman@gov.ab.ca, 403-782-8024
Kerry Clark, BC Ministry of Agriculture and Lands, Kerry.Clark@gov.bc.ca, 250-784-2559
The Canola Watch Report provides just-in-time information on canola production to growers and industry. Contributors to the Canola Agronomy Network are:
Alberta Canola Producers Commission; Alberta Agriculture and Rural Development, SaskCanola, Saskatchewan Canola Growers Association, Saskatchewan Ministry of Agriculture, Manitoba Canola Growers Association, Manitoba Agriculture, Food and Rural Initiatives, Peace River Agriculture Development Fund, B.C. Ministry of Agriculture & Lands, Agriculture and Agri-Food Canada, and the Canola Council of Canada.