Can Stripe Rust Overwinter in Manitoba?

Short Answer: Yes.

Long Answer: Normally in Manitoba, the majority of our inoculum blows in from the central US states by what is known as the “Puccinia Pathway”. However, according to Dr. Brent McCallum, a Research Scientist with AAFC in Morden, MB, there was evidence of both stripe and leaf rust overwintering on winter wheat in Manitoba a few years ago but at such low levels it wasn’t a concern. Dr. Kelly Turkington, a Research Scientist with AAFC in Lacombe, AB, also indicated overwintering of stripe rust occurred in Alberta and parts of Saskatchewan in 2010/11 where there were measurable losses. In that particular year, there was a breakdown of resistance in the 2010 planted winter wheat crop and that led to higher infections into 2011.

So yes, stripe rust can overwinter. However, the ability of stripe rust to overwinter in Manitoba, or elsewhere, would depend on factors such as the severity of the winter and snowfall amounts.

If stripe rust is seen in the fall, take note of the variety and its resistance rating. Although nothing can be done about variety selection at this point, in the future consider stripe rust resistance when evaluating and selecting winter wheat varieties. Genetics….it’s a fast and easy way to protect your crop from disease pressure!

If winter weather conditions allow for overwintering of stripe rust, it could provide a local source of inoculum early in the spring – as early as the crop starts actively growing. A cool, wet spring could also favor spread and infection of stripe rust, not only to winter wheat but to other crops such as spring wheat.

If you do see stripe rust this fall in your winter wheat crop, mark those fields as ones to watch as soon as the crop breaks dormancy next spring. If stripe rust does overwinter, a fungicide application may be necessary.

Should a fall fungicide application be considered?

There has been some recent research conducted looking at the yield response and economics of a fall fungicide application in winter wheat. From 2011 to 2013, researchers from AAFC conducted a study across Western Canada looking at a variety of management factors, including one looking at a fall fungicide application. Results were recently reported in Top Crop Manager at http://www.topcropmanager.com/business-management/improving-winter-wheat-19554. The following statements are from the article.

In regards to the fall fungicide treatment, “the study showed some benefit from the fall foliar fungicide treatment, however the increase was small and resulted in decreased net returns,” says Turkington (who was involved with the study). “In areas with confirmed stripe rust in the fall, the yields gains were a bit better. However the cost of application is prohibitive at this point compared to no application. ”

More research is currently underway by Turkington and Dr. Randy Kutcher (University of Saskatchewan) looking at a fall fungicide application, a spring fungicide application at flag leaf emergence, and a dual application (one in the fall and one in the spring).  “The preliminary results after the first two years aren’t showing much of a benefit from the fall foliar fungicide application, similar to our recent study,” Turkington says. “Some of the results suggest a dual fall and spring application does not provide any additional benefit over a spring application in Western Canada.”

So for this fall, don’t pull out the sprayer if you see stripe rust in your winter wheat.  But, be ready to scout in the spring! And look for more updates to current winter wheat research underway across Western Canada.

Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist and Holly Derksen, Field Crops Pathologist, Manitoba Agriculture; with assistance from Dr. Brent McCallum, AAFC Morden and Dr. Kelly Turkington, AAFC Lacombe.

Manitoba Agriculture on Twitter: @MBGovAg
Manitoba Agriculture on YouTube: www.youtube.com/ManitobaAgriculture
Manitoba Agriculture website: www.manitoba.ca/agriculture


Have a follow-up question?

Provincial 5-Year Average Yields for Cereal Crops in Manitoba

As Harvest 2016 progresses, there is always the question “How will this year’s yields compare to what producers typically see, i.e. average yields?”

If we use yield data reported by producers to Manitoba Agricultural Services Corporation (MASC)  over the last 5-year period (2011 to 2015), average cereal crop yields are as follows:

  • red spring wheat – 51 bushels per acre
  • feed wheat – 68 bushels per acre
  • CPS wheat – 48 bushels per acre
  • barley – 64 bushels per acre
  • oats – 91 bushels per acre
  • winter wheat – 63 bushels per acre
  • fall rye – 44 bushels per acre

Note: varieties insured as feed wheat can belong to a number of wheat classes, including Canada Western Soft White Spring (CWSWS), Canada Western Special Purpose (CWSP) and Canada Northern Hard Red (CNHR), as well as unregistered varieties.

So far in 2016, yields for cereal crops are ranging from average to above the 5-year average.  However, there is variability noted across the province, largely due to the amount of precipitation received over the growing season.

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Data source:  http://www.mmpp.com/mmpp.nsf/mmpp_browser_variety.html

Manitoba Agriculture website: www.manitoba.ca/agriculture
Manitoba Agriculture on Twitter: @MBGovAg
Manitoba Agriculture on YouTube: www.youtube.com/ManitobaAgriculture


Have a follow-up question?

Acreage Seeded to the Various Wheat Classes in Manitoba – 2016

In 2016, there was approximately 2.8 million acres of wheat seeded in Manitoba, as reported by producers for AgriInsurance purposes (pedigree and organic production not included), down from 3.0 million acres in 2015.

The Canada Western Red Spring (CWRS) class remains the largest class of wheat grown in Manitoba.  In 2016, 79.3% of provincial acreage devoted to wheat production is sown to CWRS varieties.  This is down slightly from 86.0% in 2015.

The new wheat class Canada Northern Hard Red (CNHR) is the second largest class of wheat in Manitoba at 12.1% of the total wheat acreage. The class currently includes three varieties: Faller, Prosper and Elgin ND. This class of wheat grew as 7.8% of the total wheat acres were grown to those three varieties in 2015.

Winter wheat, which includes varieties belonging to the Canada Western Red Winter (CWRW) class, and the new Canada Western Special Purpose (CWSP) class, is the third largest category at 4.9% of total wheat acres, down from 5.3% in 2015.  Keep in mind for winter wheat, the number of acres represents what was seeded in the previous fall and does not reflect the number of acres remaining after winter injury or winterkill.

Combined, CWRS, CNHR and winter wheat account for 96.3% of total wheat acres in Manitoba in 2016 (compared to 96.1% in 2015).

The remaining 3.7% of wheat acres in 2016 are comprised of the smaller classes of wheat, including Canada Western Hard White Spring (CWHWS), Canada Western Amber Durum (CWAD), Canada Western Special Purpose (CWSP – spring varieties only), Canada Western Soft White Spring (CWSWS), Canada Prairie Spring Red (CPSR) and unregistered spring wheat varieties. There was a substantial increase in CPSR acres – approximately 59,400 acres in 2016 compared to 3900 acres in 2015. However, the other smaller classes of wheat saw decreases in 2016 acreage from 2015.

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Source: http://www.mmpp.com/mmpp.nsf/sar_varieties_2016.pdf

Have a follow-up question?

Top Red Spring Wheat Varieties in Manitoba – 2016


AAC Brandon at Portage la Prairie, MB (2016). Photo by P. de Rocquigny

In 2016, there was approximately 2.2 million acres of commercial red spring wheat seeded in Manitoba, as reported by producers for AgriInsurance purposes (acres do not include pedigree or organic production).

The variety AAC Brandon, at 37.9% of Manitoba’s commercial red spring wheat acreage, was the most popular variety grown in Manitoba in 2016.  It was the fourth most popular variety in 2015 (10.4%).  AAC Brandon was first released commercially in 2015. AAC Brandon is an awned semi-dwarf variety with strong straw, good yield potential, resistant (R) to both stem and leaf rust, and has a moderately resistant (MR) rating to fusarium head blight and stripe rust.  It was developed by AAFC – Swift Current and is distributed by SeCan.

Cardale remains in second spot at 17.1% of acres, compared to 2015 where it was grown on 20.7% of acres. In third spot is Carberry at 10.2%, and rounding out the top 5 include Glenn at 7.1% and Harvest at 5.8%.  Harvest has consistently placed in the top 5 of most popular CWRS varieties in Manitoba over the past few years, showing its popularity with producers.  However, Harvest is one of the 25 CWRS varieties being reclassified to the Canada Northern Hard Red (CHHR) class by the Canadian Grain Commission effective August 1, 2018.

Rounding out the top ten are the varieties AAC Elie, CDC Plentiful, AC Domain, Muchmore, and CDC Stanley.  The top 10 varieties together were grown on 91.8% of red spring wheat acres in Manitoba. The remaining 8.2% of acres were seeded to 43 other red spring wheat varieties, many of those newer varieties gaining in acres.

Other popular varieties, based on total acres grown, include Faller and Prosper, which belong to the new Canadian Northern Hard Red (CNHR) class. AAC Penhold, a CPSR variety, is also gaining market share in Manitoba.

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Source: http://www.mmpp.com/mmpp.nsf/sar_varieties_2016.pdf

Have a follow-up question?

Estimating Harvest Losses in Cereals – Don’t Just Rely on the Grain Loss Monitor!


Winter wheat and fall rye harvest is underway in Manitoba. Since final yields aren’t determined until the crop is in the bin, attention now has to be focused on the harvest operation. Grain loss at harvesting time is a direct loss of income. The more grain saved, the greater the returns. The following information comes from 2 articles: ‘Grain Harvest Losses’ by V. Hofman with edits by Dr. J Wiersma & T. Allrich (University of Minnesota) and ‘Estimating Harvest Loss’ by G. Carlson & D. Clay (South Dakota State University).

Grain harvest losses result from shattering of the standing grain, shattering during windrowing (swathing) or direct combining, picking up the swath with the combine, and threshing, separating and cleaning within the combine. Estimates of acceptable losses for small grains such as wheat, barley and oats are placed at 3% of total yield (total yield equals harvested yield plus harvest losses).

It is usually very difficult to reduce total losses below 1 to 2% so the operator must decide on the value of the crop, the cost of combining and the time available for combining or climate conditions. Some harvest loss is unavoidable in order to get harvesting done in the time available with an end goal of cleaned harvested grain.

Estimating Harvest Losses.  Advancements in engineering have greatly improved harvest operations. Combines have various types of monitoring equipment available, including grain loss monitors, to help alert the operator to any potential problems.  A grain loss monitor is a good guide in selecting travel speed for varying conditions such as size of windrow and moisture conditions. A grain loss monitor must be calibrated to provide an acceptable grain loss reading. If the combine is used on different crops, the monitors are not only useful in limiting maximum speeds and losses, but can be used to properly feed the combine for optimum capacity.

However, a grain loss monitor is not a substitute for careful machine adjustments and good old fashioned monitoring, i.e. getting out of the combine to estimate losses. Or even better, when your local retail agronomist comes out with cold beverages, put him/her to work to estimate harvest losses.

A simple and rough estimate of grain loss requires the use of a one-foot square frame. A rough estimate of how much grain is left behind in a harvested field can be done with a few simple steps:

  1. Pick a typical area of the field after the combine has passed.
  2. Place a 1 ft by 1 ft (inside dimension) box on the ground and count the kernels found within the box. To improve accuracy, three counts (one behind the left side of the header, one behind the centre of the combine, and one behind the right side of the combine) are better.
  3. A one (1) bushel per acre loss equates to 20 wheat kernels/ft2, 14 barley kernels/ft2 and 10 oat kernels/ft2. Keep in mind that this is a ‘fudge factor’ but for the purpose of rough field estimation is an adequate estimate. There are more accurate ways to estimate harvest losses which take into consideration the width of windrower cut and combine cylinder.

If losses are on the high end, some investigation is warranted to try and identify the source of loss.  Is the crop shattering prior to the arrival of the combine (to check for losses that occurred prior to the arrival of the combine, i.e. shattering, use the method above in the unharvested areas of the field)? Are there header losses? Or are the losses due to less than perfect threshing/separation of grain within the combine?  Finding the answer may help to adjust the harvest operation and maximize the amount of grain going into the bin!

Good luck with #Harvest16!

Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Manitoba Agriculture website: www.manitoba.ca/agriculture
Manitoba Agriculture on Twitter: @MBGovAg
Manitoba Agriculture on YouTube: www.youtube.com/ManitobaAgriculture
Have a follow-up question?


Modified from Post Originally Published July 30, 2014

Staging a crop for preharvest glyphosate application for perennial weed control can be difficult when there is variability of crop staging within the targeted field.  As well, kernels in the same spike will reach physiological maturity at different times, with the middle of the head maturing first. To go back to the basics, for wheat you want to apply the preharvest glyphosate when grain moisture of the wheat crop is less than 30%.  In terms of visual assessment, the wheat crop must be in the hard dough stage.  This is when the kernel has become firm and hard and a thumbnail impression remains on the seed (see Figure 1).  Remember….you can’t rely on the color of the field as an indicator.  Walk the field and hand thresh heads to determine kernel staging.

Figure 1:  Kernels at various times during grain filling: a) kernel at watery ripe, b) kernel at late milk, c) kernel at soft dough, d) kernel at hard dough showing loss of green color, and e) kernel ripe for harvest.

Source:  Growth and development guide for spring wheat. 1995.  S.R. Simmons, E.A. Oekle & P.M. Anderson.  Photographer:  Dave Hansen.


Another visual indicator for wheat is a change in color of the peduncle, which is the part of the stem located just below the head.  It will have turned very light green or yellow at physiological maturity (Figure 2).

Source: Topics Addressing Small Grain Crop Dry-down and Harvest . 2015. Jochum Wiersma, Small Grains Specialist; Doug Holen, Crops Extension Educator and Phyllis Bongard, Educational Development and Communications Specialist


So what is special about this 30% moisture content?  At the end of the hard dough stage, the kernel has reached its maximum dry weight and the wheat is therefore physiologically mature, i.e. no more weight is added to the grain.  Therefore, final yield has been determined.

If application of a preharvest glyphosate occurs prior to the 30% moisture content, yield can be reduced, along with quality factors such as test weightIn addition, early application prior to the recommended timing may result in grain with glyphosate levels above maximum residue limits.  This could have implications depending upon target market.

So in timing an application on a variable field, this will be difficult but remember its likely better to apply on the later side than too early.  Also remember that depending on weather conditions, glyphosate can take up to 2 weeks for optimal weed control. However, under hot, dry conditions harvest could commence is as little as 7 days after application.  So keep harvest timing and weather forecasts in mind as well when planning your preharvest application.

Notes: Do not apply to wheat, or any crops, grown for seed.  Not all glyphosate products are registered for preharvest application on all crop species – always refer to individual crop labels for a list of registered uses and crop species. Check with malt barley or milling oat buyers prior to application to confirm acceptance of glyphosate-treated grain.

Following label instructions and keeping in mind pre-harvest intervals are also key component in Cereals Canada’s Keep It Clean initiative. More information is available at http://www.cerealscanada.ca/keep-it-clean/

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Have a follow-up question?

Historically, what has been seeding progress prior to May 1st?

Some producers have started their 2016 seeding operations, with spring wheat being seeded and from what I’ve heard a few acres of corn as well.  With some seeding done, I’ve been asked the question: “What has been seeding progress prior to May 1st in Manitoba in recent years?”.

Producers who participate in AgriInsurance provides seeding date information to Manitoba Agricultural Services Corporation (MASC).  This dataset provides us a historical perspective of when seeding has taken place in the past.

In Table 1, cumulative seeding progress prior to May 1st for six crop types is provided.  A five year (2010-2014) average cumulative seeding progress is noted, along with what was seeded prior to May 1st in 2015. Please note that data is for final insured crop in the ground.

Table 1:  Seeding progress in Manitoba prior to May 1st.

Historical Planting Progress prior to May 1st

Data Source:  Manitoba Agricultural Services Corporation (MASC)

What the table doesn’t show is the wide range of seeding progress prior to May 1st over the past few years.  If we look at seeding progress for red spring wheat in Manitoba, we’ve seen less than 1% of acres seeded prior to May 1st (2009, 2011, 2013 and 2014) but as many as 65% of acres (2010) planted in April.

Look for future updates to historical seeding progress as we enter May!

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Follow Manitoba Agriculture on Twitter (@MBGovAg) to receive updates on seeding progress through the weekly Manitoba Crop Report.
The weekly crop report is also available at Manitoba Crop Report.


Have a follow-up question?

Have you thought about your seedling mortality?

You’ve chosen the variety or varieties you want to grow in 2016. You’ve decided on your target plant stand. And from your seed test results, you have the percent germination and thousand kernel weight (TKW). But have you given any thought to your seedling mortality?

When calculating the seeding rate needed to achieve your target plant stand, you often hear about TKW and percent germination. But remember when calculating seeding rates, you need to take into account the seedling mortality rate, i.e. what percent of viable seed will germinate but not produce a plant.

Seedling mortality can vary greatly from year to year, and field to field. For cereals, seedling mortality rates can range from 5 to 20%.  Many farmers and agronomists have found a 5 to 10% mortality rate can be assumed. However, farmers may need to make adjustments to their seedling mortality based on factors such as available moisture, soil temperature, residue cover, seed quality, amount of seed-placed fertilizer, seeding depth, seeding date, and disease and insect pressure.

One additional factor you maybe should consider is the impact of seeding rate itself on seedling mortality or stand loss. Grant Mehring from North Dakota State University shared some recent work at the 2015 Manitoba Agronomists Conference looking at optimum seeding rates for hard red spring wheat. Across 23 environments from 2013 to 2015, his research showed increased stand loss as seeding rate increased (from a percent stand loss of 3% at the lowest seeding rate up to 21% at the highest seeding rate). His research suggests using a seedling mortality of 10 to 20%, even under good seed bed conditions.

Determining seedling mortality is not easy. Since mortality depends on the combination of conditions and management practices of individual farms, producers should keep records of emergence (and thus mortality) in their fields each year. The data collected will help in the future when calculating seeding rates.

Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Follow Manitoba Agriculture on:
Twitter: @MBGovAg
YouTube: www.youtube.com/ManitobaAgriculture


Have a follow-up question?

Why are there tall plants in my semi-dwarf wheat?

If the differences in height are sporadic throughout the field, i.e. the odd plant here and there, it is probably one of three things causing these ‘tall-types’:

  1. a result if seed of another variety was inadvertently comingled with the variety you think you have (through cleaning of equipment, bins, harvest, etc.).
  2. a variety that is segregating for plant height – is less common but in extreme growing conditions can bring differences in plant height that previously had gone unnoticed.
  3. with introduction of semi-dwarf genes (Rht1), it’s been noticed that in certain lines and genetic backgrounds a number of tall plants would appear at a low frequency from one generation to the next generation.  Fancy terms is some plants become aneuploids, meaning individual progeny has one or more chromosome missing or extra.  Monosomic deletions, i.e. plants missing one chromosome, are most commonly encountered. Because Rht1 act as a suppressor of height, their reduced dosage as in monosomics, produces plants taller than in the euploid condition.If seed is saved, half the plants derived from these tall-types should revert back to the original variety, while the other half of the plants will be the taller-types again.

There is a very good article in the Saskatchewan Seed Guide last year (page 20) further explaining these ‘tall types’ in semi-dwarf wheat: http://www.saskseed.ca/images/seed_guide2015.pdf.

Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture


Manitoba Agriculture website: www.manitoba.ca/agriculture
Manitoba Agriculture on Twitter: @MBGovAg
Manitoba Agriculture on YouTube: www.youtube.com/ManitobaAgriculture


Have a follow-up question?

Leaf Rust in Winter Wheat

Over the past few weeks, I have been touring the MCVET winter cereal sites.  This week (June 16th), I found leaf rust in a winter wheat trial near Carman, Manitoba (see Figure 1).

Leaf Rust Pustule - Winter Wheat 2015 (P.de Rocquigny)

Figure 1: Leaf Rust Pustule – Winter Wheat 2015 (Photo by Pam de Rocquigny)

Wheat leaf rust, caused by Puccinia triticina, is one of the most common diseases of wheat on worldwide.  The most characteristic signs of leaf rust infection are the rusty-red spores in round to oval pustules breaking through the leaf surface.

Yield loss and reduction of test weight are related to disease severity and time of infection. Yield losses of 30 percent to 40 percent have been recorded when severe infection occurred before flowering and damage on the flag leaf was high (> 60 percent to 100 percent).  However, if severe leaf rust does not occur until dough stages of kernel development or beyond, yield losses may be in the range of 5 percent to 15 percent.

Genetic resistance in varieties to leaf rust limits infection and retards fungus growth and spore formation. The population of the leaf rust fungus is genetically diverse and made up of many races. Different races have the ability to cause infection on varieties with different resistance genes. The leaf rust pathogen is dynamic, and races are constantly changing. Varieties formerly considered resistant can become susceptible if new rust races develop. Resistant levels are reviewed (and updated if necessary) each year for varieties and are provided in SEED MANITOBA (www.seedmb.ca).

Surveys & Monitoring is Important!  Field surveys conducted during the growing season by AAFC and MAFRD is critical as it allows the sampling of the natural populations of pathogens in the field to determine the virulence in the populations.  This in turn provides an indication of the effectiveness of current resistance sources for new crop cultivars. Growers should also monitor their crops throughout the season and be aware of disease developments in their local area. Monitoring, and early detection and reporting of rust will improve disease management outcomes.

For more information on leaf rust, its symptoms, biology, and control measures , visit MAFRD’s website at http://www.gov.mb.ca/agriculture/crops/plant-diseases/leaf-rust-wheat-barley-oats.html

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, MAFRD


Have a follow-up question?