Click here Genetic Variation in Resistance of Annual Bluegrass (Poa annua L.) to Snow Molds and Insect Pests and Mechanisms of Resistance (2002-ongoing)

Click here Summary Report on Typhula phacorrhiza Research (2002)

Click here The Fall Application of Potassium to Reduce Pink Snow Mold Damage to Fairways (Final Report 1998-2000)

Click here Fungicidal and Biological Control of Overwintering Diseases (1998)

Click here Marine Glacial Clay for Control of Microdochium nivale (2000)

Click here Effectiveness of Azoxystrobin against Downy Mildew on Turf (1999)

Click here 1997/1998 Fungicide Trials at the Cranbrook Golf Club, Cranbrook BC (1997)

Click here Apron® FL on Perennial Ryegrass Seed to Control Pythium (1997 - Final Report)

Click here Pythium Root Rot of Turfgrass (1997)

Summary Report on Typhula phacorrhiza Research (2002)

Tom Hsiang, Environmental Biology, University of Guelph, Guelph, ON

1994 looking for better strains of a fungus that could suppress snow mold diseases caused by the fungi Typhula ishikariensis and T. incarnata. By 1997, we had identified five strains out of several hundred that work as well at suppressing gray snow mold as conventional fungicides. This work during the first three years was supported by the Canadian Turfgrass Research Foundation with matching funds from the Ontario Ministry of Education. In 1998, we started on a new phase of this research with funding from the Canadian Turfgrass Research Foundation. This money was matched by Nu-Gro Corporation, and then funding from both organizations was matched by a federal program, the Natural Sciences and Engineering Research Council of Canada for 1998 to 2001. As a result of the increased funding, we were able to expand the study to sites across Canada and began more intensive work on biological processes involved in suppression and to prepare a data package for submission to regulatory agencies. Although T. phacorrhiza can be found in abundance in corn fields after spring snow melt, the large majority of these isolates have little or no effect against gray snow mold.

Over the past four years, there have been many spectacular successes with biological control of snow molds with T. phacorrhiza isolate TP94671. There also have been some failures and these are all summarized in Appendix AB. In Fall 2000, a pre-submission package was prepared for the PMRA . By early 2001, the PMRA requested that the package be submitted for joint review to PMRA and EPA. In May, 2001, Suzanne Beattie and Tom Hsiang went to Ottawa to meet with representatives of the PMRA in person and EPA by teleconferencing. The outcome of this meeting was that the PMRA asserted that field produced biocontrol inoculum was not sufficiently safe (for human health), and wanted to see development of an in vitro method of production, as well as other toxicological tests.

At the same time in spring 2001, results were coming in from the largest set of field trials conducted in this project. There were mixed reports, but the most troubling was from Invermere, B.C. where spectacularly good results in spring 2000 were followed by spectacularly bad results in 2001. We suspected that something had gone wrong with the inoculum production since we had been asked to produce almost 200 kg of biocontrol inoculum for the previous fall, where we normally just produce a few kg a year. Some of this inoculum was contaminated by other organisms, since we did not have the facilities for quality control on this scale of production. One good result from 2001, was that the field production of T. phacorrhiza on corn residue near Owen Sound was very successful.

In summer 2001, we collected our field-produced T. phacorrhiza and tested the sclerotia for viability and genetic identity. All were found to be of high viability and of the same genetic strain that was placed there the previous fall. In fall 2001, we tested some of this field-produced inoculum at four sites in Ontario and one in Quebec. The results after snowmelt in 2002 were mostly positive, and the full details are presented in Appendix AA attached, but the field-produced corn-based inoculum did not perform as well as the lab-produced bran-based inoculum. At the same time, another sclerotial production trial was being conducted by Brian Peirce north of Owen Sound. Abundant sclerotia were produced, but these did not resemble the typical T. phacorrhiza. After DNA fingerprinting tests, these sclerotia turned out to be another species of Typhula and not the desired T. phacorrhiza which had been reinoculated onto corn piles in the form of the previous year's corn inoclum.

In May 2001, CTRF re-affirmed its commitment to this project by funding a two-year continuation of the year. In September 2001, Nu-Gro finally agreed to also continue funding this research, but at 40% of the level of

CTRF funding. An application was also made to NSERC for matching funding, but they have not yet decided. In June 2002, Tom Hsiang and Teri Yamada met at Nu-Gro Headquarters in Brantford with Brian Peirce, Suzanne Beattie and Sheldon Witte. Nu-Gro also re-stated its commitment to this project, and Brian Peirce began working on gamma sterilization method to produce sterile wheat bran for T. phacorrhiza production. Our continuing research is to develop ways of growing and formulating the inoculum of a select isolate of T. phacorrhiza that is antagonistic to gray snow mold and pink snow mold, and providing data to satisfy product registration and regulatory requirements.

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The Fall Application of Potassium to Reduce Pink Snow Mold Damage to Fairways (2000) 1999/2000 and 2000/2001 (final report)

Dave Sullivan, Master Superintendent at the Castlegar Golf Club, Castlegar, BC & Leslie MacDonald, Plant Pathologist at the BC Ministry of Agriculture, Food & Fisheries, Abbotsford, BC

Executive Summary
The wet, cool spring, lack of frozen ground on the course through the winter, and low soil temperatures in March and April 2000 contributed to higher disease levels at susceptible locations in comparison to previous years. However, trial results in spring 2000 had a high degree of variability because the experimental design was not set up properly. This made it difficult to draw conclusions.

Results in spring 2001 showed that fall potassium applications at 1.72 lbs. K2O/1000 sq. ft. were beneficial in reducing pink snow mold damage. Potassium at this rate had an average of only 6% damage. There was no significant difference in control between the 1.72 lb. rate and the 2.97 lb. rate indicating no advantage to using a higher rate at this golf course. However, the 1.72 lb. rate was significantly better than the 1.15 lb. and 0 lb. rates. These observations suggest that a fall potassium application is an important part of a winter disease management program. The other components of this program include the provision of good drainage on the fairway and over-seeding with well-adapted varieties. Drainage minimizes the moisture which the fungus needs for infection. Over-seeding encourages recovery and provides competition for Poa annua.

One application of Quintozene 75WP at 8 oz/1000 sq. ft. gave excellent control (0.3% damage) for spring 2001. In this trial, the level of control from the fungicide treatment was not statistically different in comparison to the fall application of 1.72 lbs. K2O/1000 sq. ft. However, one could actually observe that the quintozene treatment did provide better disease control, which was the difference between 6% and 0.3%. Cost, member feedback and philosophy on fungicide use are the major considerations required in deciding which fairway program to use. Observations in golfer expectations suggest that once a golf course starts to pursue high quality fairways in the spring through a fungicide treatment, golfers will come to expect high quality each spring. There will likely be tremendous pressure to continue the use of fungicides each year.

Fall potassium applications may have a role in reducing pink snow mold damage on middle to lower budget golf courses if used in conjunction with good drainage and over-seeding. However, if quintozene becomes unavailable in the future, there is no ready fungicide substitute that is as cost-effective and reliable for fairway applications. Fall potassium use may be revisited by courses previously relying on a fungicide application.

There is debate about which nitrogen:potassium ratio is best. The ratio of 1:1.8 was used for the 1.72 lbs, K2O/1000 sq. ft. treatment. There should be no problem with this rate. The main concern when applying extra potassium is to use caution when base saturation levels of magnesium are low, especially when the soil CEC is low. High levels of potassium may saturate the CEC sites at the expense of other cations such as magnesium. Soil tests are needed to monitor the situation.

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Fungicidal and Biological Control of Overwintering Diseases (1998)

D.W. Li and J. B. Ross, Prairie Turfgrass Research Centre, Olds, AB

Summary This trial was developed to determine the effectiveness of various control products for use on overwintering diseases in Golden, British Columbia. The treatment that consisted of Rovral Green 360ml, Daconil 375ml with Tersan 1991 60g, Typhula phacorrhiza 100grams/m2 was the only treatment that showed significantly less disease than the untreated controls.

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Marine Glacial Clay for Control of Microdochium nivale (2000)

Ray Benedetti, Assistant Superintendent, Arthur Riome, Superintendent, Fairview Mountain Golf Club, Oliver, BC Tim Garland, Inland Machiner MFG Ltd., and Leslie MacDonald, BC Ministry of Agriculture, Food & Fisheries

Abstract
There was no significant difference between the clay treatments and the untreated turfgrass for disease control, colour or vigour. However, there were no detrimental effects observed on the turfgrass.

The quintozene treatment provided the best disease control against pink snow mold. It also gave better turfgrass vigour for the first week after snowfall.

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Effectiveness of Azoxystrobin against Downy Mildew on Turf (1999)

Dave Sandulo, Ernie Whitelaw, Leslie MacDonald and Elizabeth Hudgins, Ladysmith, BC

Azoxystrobin was applied at three different rates to downy mildew infected bentgrass and Poa annua on a practice green on Vancouver Island during the spring of 1999. It did not improve colour or vigour during the three weeks after the second application. There was no damage to the turf from any of the application rates, and the product did not make downy mildew more severe. Azoxystrobin is marketed as Heritage in the U.S.

Azoxystrobin may inhibit the growth of Sclerophthora sp. (which causes downy mildew) and may help reduce the future level of disease but that cannot be determined from this study. Cultural controls recommended for downy mildew such as avoiding nitrogen deficiency, and reducing moisture and humidity in the plant canopy continue to be the recommended practices.

An observation was that the treated green seemed to be less disease-prone throughout the summer and into the fall. No Fusarium patch was observed on this green. (summary by Leslie Macdonald)

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1997/1998 Fungicide Trials at the Cranbrook Golf Club (1997)

Mike Baden,C.G.S.A., Supintendent & Peter Kruetz, Assistant Superintendent Cranbrook Golf Club, Cranbrook, BC

Conclusions
The best protection was with the Banner. Little to no mold was present on all 8 plots. Some mold present on the Poa green but definitely the least. One side effect at the rates used was that it burned the leaf tips (especially the poa) although after a few mowings in the spring this damage was gone. These plots turned a darker green and remained a noticeably darker colour up until August (time of writing this report). This is apparently called a Cytokinin effect. The Banner label says to make 1 application for snow mold control at the high rate. We found that it is important to make no more than 1 application of Banner for snow mold to avoid burning tips. If more fungicides are needed, then a different one should be used. One should also consider a lower rate for Banner or an alternate fungicide for application on severely stressed greens."

Second best was the FFII and the Heritage which were very close to the same. The biggest difference was that the FFII was a lot greener due to its fertilizer content.

Rovral/Daconil finished last and although there was not a lot of mold on any plots it definitely didn't perform as good as the others in this test.

NOTE: On the Poa green the only good protection was the Banner. The others were equally poor with 30-40% mold damage.

Although this past winter was relatively light with regards to disease pressure, we feel that the results give an accurate account of product performance on this course. This project was a worthwhile undertaking for us to find a combination that would give us effective control and I would encourage others who are in a similar situation to give it a try. We need more "real world" experiments like this to help us determine how products perform "in the field".

Next year
From what we have learned at this course, our basic treatment plan next winter for most of our greens will probably be; fertilizer/DSB (for fall dollar spot)-Banner (at a lower rate to avoid tip burn)-FFII-FFII.

At this course we are always trying different ways of reducing chemical use but so far the use of fungicides is required for adequate snow mold control and avoid unemployment!

Practical applications (how does this project affect you)
This study demonstrated that the effects of fungicides, or combinations of fungicides, at controlling snow mold vary according to the age of the green, its health status and the turf species present. In addition to providing disease control, some products offered additional benefits such as early spring green up.

Although complete snow mold control still requires several fungicide applications, good control can be achieved with a reduced number of the right combination of products. It is however important to test the products or the combination of products, and evaluate fungicide performance on specific green conditions.

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Apron® FL on Perennial Ryegrass Seed to Control Pythium (1997 - Final Report)

Syd Pickerell, P.Ag. and John Bittner, B.Sc., Dawson Seed Co. Ltd., Langley, BC

Summary
To date, on the four sites we have seeded, we have not observed any difference in performance between Apron® FL treated Perennial Ryegrass and untreated (bare) Perennial Ryegrass. Top growth and root depth did not display any measurable differences. It was obvious the seed was not challenged by Pythium at these particular sites; this was born out when the soil samples, collected at each site, were analyzed by IG Micromed Environmental Inc. in Richmond, B.C.

Practical applications (how does this project affect you):
The purpose of the trial was to evaluate the merit of Apron FL treated perennial ryegrass seed in the battle against Pythium. The 1997 treatment sites were composed of two golf courses and one athletic field. Observations during the germination and growing phases (July to October 1997) indicated no differences in turfgrass performance between the Apron FL treated perennial Ryegrass and the untreated one.

Observations at the various sites also seemed to indicate that Pythium was either absent or present in insufficient level to cause damage. Results from the analysis of the soil samples, collected prior to the establishment of the trials, will provide confirmation of the presence or absence of Pythium.

A second plot was seeded in the spring of 1998 to evaluate the merit of this seed treatment under more stressful growing conditions. As Pythium is a major problem for the turf industry, and can have devastating effects on turf establishment and growth, the use of treated seeds offer a useful and valuable way to help produce a healthy, dense turf stand.

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Pythium Root Rot of Turfgrass (1997)

Sharon de Jong, BC Ministry of Agriculture and Food, Abbotsford, BC

Practical applications (how does this project affect you)
1- Pathogenicity tests of Fraser Valley Pythium isolates on bentgrass
Only certain Pythium isolates cause moderate to severe disease symptoms on bentgrass in the Fraser Valley. Amongs the aggressive species, Pythium volutum is the most common pathogenic species associated with Pythium crown and root rot of turfgrass in BC. Testing for the presence of specific isolates using the molecular technique is possible and can provide an indication of the disease potential of a particular area.

2- Microdochium bolleyi and Pythium interaction trial
Although Microdochium bolleyi is often found associated with Pythium, its presence does not produce significant levels of disease, nor does it affect the level of disease caused by Pythium.

3- Fungicidal control of Pythium root rot on bentgrass
Although the fungicide efficacy trials were inconclusive, they indicated that drench applications of fosetyl-Al, etridiazole and metalaxyl were not harmful to turfgrass plants.
An application however would only be cost-effective when known pathogenic Pythium species are present.

4- Traditional and molecular detection of Pythium
This study provided additional information on Pythium species and structures, which will help improve the accuracy of Pythium diagnoses.
Molecular techniques can detect species prior to the development of disease symptoms; it can be used as a tool for disease monitoring. The study also showed that although Pythium may be present in a sample, its effect may be secondary and its presence may be the result of a different problem. Knowing which Pythium species we are dealing with will help in making the appropriate management decision.
The use of both traditional and molecular detection methods will provide accurate tools to diagnose and manage Pythium diseases.

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