CROP MAKING EFFECTIVE FUNGICIDE DECISIONS MANAGER. FUNGICIDE BASICS How fungicides work PG 4. Three factors to consider PG 3

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1 TOP CROP MANAGER FUNGICIDE GUIDE APRIL 2015 topcropmanager.com MAKING EFFECTIVE FUNGICIDE DECISIONS Three factors to consider PG 3 FUNGICIDE BASICS How fungicides work PG 4

2 Creating a more advanced fungicide with more advanced results was no accident. After years of extensive research in the lab and more importantly in the field, we ve developed our most advanced fungicide ever: new Priaxor fungicide. It helps canola and pulse growers maximize their crops yield potential* thanks to the combination of the new active ingredient Xemium and the proven benefits** of AgCelence. The result is more consistent and continuous disease control. And greater returns for you. Visit agsolutions.ca/priaxor or contact AgSolutions Customer Care at BASF (2273) for more information. *All comparisons are to untreated, unless otherwise stated. **AgCelence benefits refer to products that contain the active ingredient pyraclostrobin. Always read and follow label directions. AgSolutions is a registered trade-mark of BASF Corporation; AgCelence, PRIAXOR, and XEMIUM are registered trade-marks of BASF SE; all used with permission of BASF Canada Inc. PRIAXOR should be used in a preventative disease control program BASF Canada Inc.

3 KNOW. GROW. APRIL 2015 TOP CROP MANAGER WEST PESTS AND DISEASES Fungicide Guide 2015 PESTS AND DISEASES 3 Make the most of fungicide applications by Carolyn King 4 How fungicides work PHOTOS COURTESY OF KELLY TURKINGTON, AAFC. FUNGICIDE CHARTS CEREALS 8 OILSEEDS 8 PULSES 12 POTATOES 12 SPECIALTY CROPS ON THE COVER For leaf spot diseases such as septoria, protecting the upper canopy leaves is key because those leaves make a big contribution to grain fill and yield. PHOTO BY KELLY TURKINGTON, AAFC. Top Crop Manager thanks BASF for sponsoring this year s Fungicide Guide. TOP CROP MANAGER Published as part of Top Crop Manager, April 2015, by Annex Publishing & Printing Inc. PO Box 530, 105 Donly Drive South, Simcoe, ON N3Y 4N5 Canada Tel: (519) Fax: (519) Editor: Janet Kanters Western Field Editor: Bruce Barker Eastern National Account Manager: Steve McCabe Western National Account Manager: Michelle Allison Group Publisher: Diane Kleer Canada s original technical crop production magazine, The Western edition of Top Crop Manager, is published nine times a year. To be sure of your copies, either mail, fax or your name and full postal address to Top Crop Manager, or subscribe at: There is no charge for qualified readers. MAKE THE MOST OF FUNGICIDE APPLICATIONS Evaluating several factors is essential for effective fungicide decisions. by Carolyn King Plant pathologists Kelly Turkington of Agriculture and Agri-Food Canada and Randy Kutcher of the University of Saskatchewan look at how to make the most of your fungicide applications and what kinds of results you can expect from those applications. Disease risk and development depend on the interaction of the host, the environment and the pathogen. Evaluating those three factors in each field is essential for effective fungicide decisions. Consider the host When it comes to the host, the biggest factor is how susceptible the crop variety is to the disease. That affects whether or not a fungicide application is needed, which fungicide to apply, what rate to apply, when to apply it and how to apply it. Turkington and Kutcher note that, if the crop variety is resistant, then spraying a fungicide isn t likely to provide much additional benefit because the crop has resistance genes for controlling the disease. If the variety is susceptible or very susceptible, then the disease could develop very rapidly. So, timely scouting is crucial to enable timely fungicide applications on the key plant tissues that need to be protected. For instance, if the host is a cereal crop and the disease concern is a leaf spot disease, then protecting the upper canopy leaves is key because those leaves make a big contribution to grain fill and yield, Turkington says. The fungicide needs to be applied when those upper leaves have emerged and while they still remain healthy so that the fungicide can protect them from the disease. If the concern is Fusarium head blight, then you apply the fungicide after the head is emerged, and you use application technology, like angled nozzles, to improve your ability to coat the head with fungicide. ABOVE: Fungicides won t kill a pathogen that is already well established in the infected tissue. SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL

4 Another host consideration is the crop s yield potential. If the crop is not going to yield very well, then a fungicide application could be a waste of money because, first of all, you re probably not going to get enough of a yield response to cover the cost of the application, and secondly, the crop canopy is going to be so light that the canopy microenvironmental conditions won t be overly conducive for disease development, Turkington explains. If the crop has an extremely high yield potential, then you have potential for a good response to spraying, plus you ll have a dense crop canopy that maintains moisture within the crop, which results in a higher risk of disease. Consider the pathogen When it comes to the pathogen, the first consideration is to make sure you re actually dealing with a fungal pathogen. For example, sometimes leaf damage caused by herbicides or foliar fertilizers or by hail, drought, frost or heat can be mistaken for fungal disease symptoms. Or a bacterial disease might be mistaken for a fungal disease. If the problem isn t caused by a fungus, then applying a fungicide won t help. If you establish the crop does have a fungal disease and you accurately identify the specific fungal disease, then that will CONTINUED ON PAGE 10 HOW FUNGICIDES WORK Fungicides can be grouped in various ways to describe how they work. One approach is to classify them based on their mobility: those that stay on the plant s surface; and those that penetrate into the plant. Contact fungicides Contact, or protectant, fungicides remain on the plant surface. They maintain a fungicidal barrier, protecting the treated tissue from infection, Turkington notes. Because they stay on the outside of the plant, they are susceptible to weathering to being broken down by sunlight or washed off by rainfall so repeated applications are often needed. And because contact fungicides don t spread within the plant, you need to have good application technology and good coverage of the key plant tissues that need to be protected to maintain crop yield. Contact fungicides mainly target spore germination and in some cases very early growth of the spores. Systemic fungicides Systemic, or penetrating, fungicides move into the plant tissue. However, unlike systemic herbicides such as glyphosate, systemic fungicides do not move throughout the whole plant. [Some types of systemic fungicides] have very limited movement, remaining close to the point of contact on the plant tissue. Other types are referred to as translaminar, which means that, if they are sprayed on the upper surface of the leaf, they penetrate into the leaf tissue, through the middle part of the leaf, to the other side of the leaf, Turkington explains. And some other systemic fungicides, depending on their level of solubility in water, get caught up with the water transpiration stream. These types move up from the base of the leaf to its tip, not backwards into the plant, so they don t go down into the roots or up into the growing point. Systemic fungicides act as protectants and also have some ability to limit further pathogen development. But they won t kill a pathogen that is already well established in the infected tissue. These fungicides are most active either before infection or during early stages of infection [within about one to three days after infection, which is often referred to as kick-back action or curative activity], Turkington says. Typically if a plant already has lesions, that infection probably occurred at least seven to 10 days earlier. By the time many lesions have appeared on key plant tissues, a fungicide application will provide little benefit because it will have limited activity against existing lesions. It may limit further development of existing infections, especially if they are relatively new; however, eventually the pathogen will continue to grow and produce spores. Once systemic fungicides are inside the plant, they may be more persistent and have a broader period of activity than contact fungicides. However, they will eventually be metabolized in the plant tissue, so their effectiveness will decline over time. Another way to group fungicides is based on their breadth of activity the number of sites they attack within the pathogen. Single-site fungicides have very specific targets within the pathogen, such as a single metabolic or energy production pathway or a single critical protein or enzyme. Most single-site fungicides are systemic fungicides. Because they are very targeted, single-site fungicides typically don t cause a lot of damage to plant tissue. On the other hand, with only one point of attack, it s easier for the pathogen to develop resistance to the fungicide. So rotating fungicides and using products with more than one active ingredient are especially important to reduce the risk of fungicide resistance. Multi-site fungicides are active against multiple targets within the pathogen, and they may be active on different types of fungi. They are mainly contact fungicides and tend to be older products. Because they have activity against multiple sites, the risk of pathogen resistance is lower. However, in some cases, there may be a higher risk of damage to the plant. The Fungicide Resistance Action Committee (FRAC) classifies fungicides by their resistance risk. For example, single-site fungicides like the strobilurins (Group 11) have a high risk of resistance, the triazoles (Group 3) and carboxamides (Group 7) have a medium risk, and multi-site fungicides, like the dithiocarbamates (Group M3) and the phthalimides (Group M5), have a low risk. Turkington and Kutcher explain how fungicide resistance develops. The population of a pathogen within a field might have millions or billions of individuals, and a few of those individuals might happen to have some difference in their genetic makeup so that they are not affected by a particular fungicide. Those individuals will survive an application of that fungicide and will pass their resistance along to their offspring. Repeated applications of the same fungicide will continue to select for members of that pathogen population that are resistant to that fungicide. Eventually, resistant individuals will predominate in the field, and the fungicide will no longer be an effective option for controlling that pathogen in that field. 4 SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL 2015

5 Without protection from sclerotinia, you could be missing a golden opportunity. Growing the best canola crop takes a lot of work all season long. So make sure you protect your investment and all of your effort from late-season disease. A preventative application of Lance fungicide delivers unprecedented control of the potentially devastating disease, sclerotinia. Without protection, your crop is vulnerable to losing the valuable yield potential you ve worked so hard to build. So why overlook what you ve gained? Follow through with Lance fungicide. For details, visit agsolutions.ca/lance or call AgSolutions Customer Care at BASF (2273). Always read and follow label directions. AgSolutions is a registered trade-mark of BASF Corporation; and LANCE is a registered trade-mark of BASF SE; all used with permission by BASF Canada Inc. LANCE fungicide should be used in a preventative disease control program BASF Canada Inc.

6 FUNGICIDES 2015 FUNGICIDE CEREALS ACAPELA (picoxystrobin) BLANKET (azoxystrobin, propiconazole) BRAVO ZN (chlorothalonil) BUMPER 418EC CARAMBA (metconazole) DITHANE DG RAINSHIELD ECHO 72 (chlorothalonil) EVITO (fluoxastrobin) FOLICUR EW (tebuconazole) FUSE (tebuconazole) FUNGICIDE GROUP 11 3,11 M 3 3 M M RESISTANCE RISK High Med Low Med Med Low Low High Med Med WHEAT Fusarium Head Blight S S S S S Powdery Mildew Leaf Rust Stem Rust Stripe Rust Septoria Glume Blotch Septoria Leaf Spot Spot Blotch S Tan Spot BARLEY Fusarium Head Blight S Net Blotch Powdery Mildew Barley Leaf Rust Stem Rust Stripe Rust Scald Septoria Leaf Spot Spot Blotch S OAT Crown Rust Septoria Leaf Spot Stem Rust RYE Powdery Mildew Leaf Rust Scald CORN Gray Leaf Spot Leaf Blight and Eye Spot Common Rust NOTES: Fungicide effective against the disease S Suppression only 6 SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL 2015

7 FUNGICIDES 2015 FUNGICIDE HEADLINE EC (pyraclostrobin) MANZATE PRODUCTS NUFARM PROPICONAZOLE PALLISER (tebuconazole) PENNCOZEB 75 DF PIVOT 418 EC PRIAXOR (fluxapyroxad, pyraclostrobin) PROLINE 480 SC (prothioconazole) PROPEL PROSARO 250 EC (tebuconazole, prothioconazole) QUADRIS (azoxystrobin) QUILT (azoxystrobin, propiconazole) TILT 250E TWINLINE (metconazole, pyraclostrobin) VERTISAN (penthiopyrad) 11 M 3 3 M 3 7, ,3 11 3,11 3 3,11 7 High Low Med Med Low Med Med Med Med Med High Med Med Med Med S S S S S S S S S S S SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL

8 FUNGICIDES 2015 OILSEEDS & PULSES ACAPELA (picoxystrobin) ALLEGRO 500F (fluazinam) ASTOUND (cyprodinil, fludioxonil) BRAVO 500 (chlorothalonil) BUMPER 418EC CARAMBA (metconazole) CONTANS - (bio-fungicide) (Coniothyrium minitans strain) COPPER 53W (copper sulphate) DELARO (prothioconazole, trifloxystrobin) DITHANE DG RAINSHIELD ECHO 720 (chlorothalonil) EVITO (fluoxastrobin) FOLICUR EW (tebuconazole) HEADLINE DUO (boscalid, pyraclostrobin) HEADLINE EC (pyraclostrobin) KOCIDE 2000 (copper hydroxide) FUNGICIDE GROUP ,12 M 3 3 N/A M 3,11 M M ,11 11 M RESISTANCE RISK High Low Med Low Med Med N/A Low Med Low Low High Med Med High Low OILSEEDS CANOLA Alternaria Black Spot Blackleg Sclerotinia White Mould FLAX Pasmo RAPESEED, ORIENTAL MUSTARD Sclerotinia White Mould SOYBEAN Asian Soybean Rust Anthracnose Frogeye/Cercospora Leaf Spot S Powdery Mildew Sclerotinia White Mould S S S PULSES BEAN Anthracnose Asian Soybean Rust Bacterial Blight Botrytis Gray Mould Downy Mildew Powdery Mildew Uromyces (Rust) Sclerotinia White Mould S CHICKPEA Ascochyta Blight Asian Soybean Rust Botrytis Gray Mould Sclerotinia White Mould S FABABEAN Ascochyta Blight Asian Soybean Rust Powdery Mildew Sclerotinia White Mould LENTIL Anthracnose Ascochyta Blight Asian Soybean Rust Botrytis Gray Mould Sclerotinia White Mould S FIELD PEA Ascochyta Blight Asian Soybean Rust Botrytis Gray Mould Mycosphaerella Blight Powdery Mildew Sclerotinia White Mould S NOTES: Fungicide effective against the disease S Suppression only 8 SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL 2015

9 FUNGICIDES 2015 KUMULUS DF (sulphur) LANCE (boscalid) MANZATE PRODUCTS NUFARM PROPICONAZOLE 418EC OVERALL 240 SC (iprodione) PARASOL PRODUCTS (copper hydroxide) PENNCOZEB 75 DF PIVOT 418 EC PRIAXOR (fluxapyroxad, pyraclostrobin) PRIAXOR DS (fluxapyroxad, pyraclostrobin) PROLINE (prothioconazole) PROPEL PROPULSE (prothioconazole + fluopyram) QUADRIS (azoxystrobin) QUASH (metconazole) QUILT (azoxystrobin, propiconazole) ROVRAL FLO/ROVRAL RX (iprodione) SENATOR 70WP (thiophanate-methyl) SERENADE CPB - (bio-fungicide) (Bacillus subtilis - QST 713 strain) STRATEGO (propiconazole, trifloxystrobin) TILT 250E VERISAN (penthiopyrad) M 7 M 3 2 M M 3 7,11 7, , , , Low Med Low Med Med- High Low Low Med Med Med Med Med Med High Med Med Med- High High Low Med Med Med S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL

10 Stripe rust on winter wheat (early symptoms, left, and mature symptoms, right): Because stripe rust inoculum comes from outside the field, spraying a fungicide when the disease is starting to develop can provide very effective control. determine which fungicide products to consider, depending on whether that disease is on the label. The specific fungal disease also determines the source of inoculum, which influences fungicide effectiveness and timing. A good example is leaf spot diseases versus stripe rust in wheat. For leaf diseases like tan spot or septoria in wheat or net blotch or scald in barley, the inoculum is largely coming from infested crop residues on the soil surface. If you have early-season infections and you spray a fungicide at the herbicide timing, you are only protecting the green leaf tissue that is out at that time. So if you sprayed at the two- or three-leaf stage, then the fourth leaf will not be protected at all, Turkington says. Because the inoculum is continually coming from the residue within the field and from well-established lesions in the crop, new plant tissue will be exposed to the disease as the plant grows. Research and experience show herbicide timing is not the best option for cereal leaf disease management. In contrast, with stripe rust, the inoculum is coming from outside of the field. Because of that, sometimes if you spray early when the disease is starting to develop, the fungicide can provide very effective control of the disease. Now, you may still have inoculum in the area, so you ll probably have to spray again to protect the upper canopy leaves as the crop comes into the flag leaf or head emergence stage. Another factor is whether the disease is monocyclic, with one infection cycle each year, or polycyclic, with multiple infection cycles each year. The two pathologists explain that, often with a monocyclic disease, there is a key crop growth stage that should be targeted with the fungicide. For example, with sclerotinia, the key stage to protect is flowering. For Fusarium head blight, the key stage is anthesis (flowering), once the head has come out of the boot. In contrast, with a polycyclic disease, such as ascochyta in chickpeas, multiple fungicide applications may be needed during the growing season, especially with a susceptible crop variety. How the pathogen reproduces is also a factor. For instance, in a pathogen that reproduces asexually, one generation is usually genetically the same as the next, although mutations can occur occasionally. So the pathogen s ability to develop new strains is relatively low. In contrast, in a pathogen that reproduces sexually, genetic recombination occurs all the time, so there s a much higher likelihood some of the offspring may happen to have the ability to resist the fungicide. Consider the environment With the environment, a major factor is whether the weather conditions favour or restrict disease development, which influences inoculum production, infection potential and disease development. High moisture and moderate temperatures are extremely favourable for disease development. Under those conditions, you need to be scouting and thinking about whether you need to use a fungicide or not. Weather conditions also influence fungicide application success, persistence and period of activity. For instance, if it rains heavily soon after a fungicide is applied, the rain could wash the fungicide off. The weather also affects whether you can spray the field without getting stuck or whether an aerial application might be needed. Consider the fungicide Plant pathologists always get asked: What product is best? But the biggest factor influencing the economics and potential return from CONTINUED ON PAGE SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL 2015

11 The majority of yield potential is determined at flag-leaf. This is no time to compromise. Because up to 65% of the crop s yield potential is determined at flag-leaf 1, disease control is critical at this stage. Twinline doesn t stop there. Unlike other fungicides, in addition to exceptional disease control, it delivers the unique plant health benefits 2 of AgCelence. In short that means greener, larger leaves and stronger stems, resulting in higher yield potential. 3 So it s no wonder Twinline is ranked the #1 leaf disease fungicide by growers 4. Check it out for yourself at agsolutions.ca/twinline or call AgSolutions Customer Care at BASF (2273). 1 HGCA Wheat disease management guide, AgCelence benefits refer to products that contain the active ingredient pyraclostrobin. 3 All comparisons are to untreated, unless otherwise stated. 4 Stratus, Always read and follow label directions. AgSolutions is a registered trade-mark of BASF Corporation; AgCelence, and TWINLINE are registered trade-marks of BASF SE; all used with permission by BASF Canada Inc. TWINLINE fungicide should be used in a preventative disease control program BASF Canada Inc.

12 FUNGICIDES 2015 POTATOES FUNGICIDE GROUP ACTIVE INGREDIENT RESISTANCE RISK Acrobat WP 40 dimethomorph Low - Medium Allegro 500F 29 fluazinam Low Bravo ZN M chlorothalonil Low Cabrio Plus 11, M2 pyraclostrobin, metiram Medium Cantus 7 boscalid Medium Contans (bio-fungicide) n/c Coniothyrium minitans strain Unknown Copper 53W M copper sulphate Low Copper Spray M copper oxychloride Low Curzate 60 DF 27, M3 cymoxanil Low - Medium Dithane DG Rainshield M mancozeb Low Echo 720/90DF M chlorothalonil Low Evito 11 fluoxastrobin High Gavel 75 DF 22, M3 mancozeb, zoxamide Low - Medium Headline EC 11 pyraclostrobin High Kocide 2000 M copper hydroxide Low Lance 7 boscalid Medium Luna Tranquility 7,9 fluopyram, pyrimethanil Medium Manzate Products - 200, 75DF, Pro-stick M mancozeb Low Parasol Products - DP, WP, Flowable, WG M copper hydroxide Low Penncozeb 75DF Raincoat M mancozeb Low Polyram DF M metiram Low Presidio 43 fluopicolide n/c Quadris 11 azoxystrobin High Quadris Top 11, 3 azoxystrobin, difenoconazole Medium Quash 3 metconazole Medium Ranman 400 SC 21 cyazofamid Medium - High Reason 500SC 11 fenamidone High Revus 40 mandipropamid Low - Medium Ridomil Gold / Bravo, Ridomil Gold SL / Bravo 4,M chlorothalonil, metalaxyl-m Low Ridomil Gold 480EC, Ridomil Gold 480SL 4 metalaxyl-m High Ridomil Gold MZ 68WP 4,M metalaxyl, mancozeb Low Scala SC 9 pyrimethanil Medium Serenade SOIL (bio-fungicide) 44 Bacillus subtilis (QST 713 strain) Low Serenade MAX (bio-fungicide) 44 Bacillus subtilis (QST 713 strain) Low Tanos 50 DF 11, 27 famoxadone, cymoxanil High Tattoo C 28, M propamocarb HCl, chlorothalonil Low - Medium Vertisan 7 penthiopyrad Medium Zampro 40, 45 ametoctradin, dimethomorph Low NOTES: Fungicide effective against the disease a Must not be used alone, only as a tank mix b In-furrow treatment (suppression only) c Suppression only SPECIALTY CROPS BUMPER 418EC DITHANE DG RAINSHIELD FUNGICIDE HEADLINE EC (pyraclostrobin) LANCE (boscalid) MANZATE PRODUCTS NUFARM PROPICONAZOLE 418EC FUNGICIDE GROUP 3 M 11 7 M 3 RESISTANCE RISK Med Low High Med Low Med ALFALFA (GROWN FOR SEED) Blossom Blight Common Leaf Spot Spring Black Stem & Leaf Spot Sclerotinia CANARY SEED Septoria Leaf Mottle S S CORIANDER Blossom Blight GRASSES (GROWN FOR SEED) Leaf Rust & Stem Rust Powdery Mildew TIMOTHY Purple Eye Spot NOTES: Fungicide effective against the disease S Suppression only 12 SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL 2015

13 BOTRYTIS GRAY MOULD / BOTRYTIS VINE ROT EARLY BLIGHT LATE BLIGHT LATE BLIGHT TUBER ROT DISEASES PYTHIUM LEAK FUNGICIDES 2015 PINK ROT RHIZOCTONIA CANKER, BLACK SCURF SILVER SCURF WHITE MOULD / SCLEROTINIA ROT a a a c b b d a d b b d c c b c c c c c c d d c c d May be beneficial to tank mix with protectant to control Group 11 (strobilurin)-insensitive strains n/c Not classified OVERALL 240 SC (iprodione) PENNCOZEB 75 DF PIVOT 418 EC PRIAXOR (fluxapyroxad, pyraclostrobin) FUNGICIDE PROPEL QUADRIS (azoxystrobin) ROVRAL FLO/ROVRAL RX (iprodione) TILT 250E 2 M 3 7, Med-High Low Med Med Med High Med-High Med S S S S SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL

14 With net form net blotch and other leaf spot diseases in cereals, inoculum is continually coming from infested residues in the field, so new plant tissue will be exposed to the disease as the plant grows. spraying is the decision whether or not to spray, Turkington says. The next biggest factor is application timing and application technology, like using adequate volumes of water, and getting good coverage and penetration into the crop canopy. And the factor with the least impact is the particular product you choose. As long as the products are registered for the disease of concern and you re using label rates and fungicide resistance hasn t developed for any of the products, then the main consideration when choosing between one product and another is which one is cheapest. Since the decision on whether or not to spray is so crucial, it follows that timely scouting, accurate disease diagnosis, and accurate assessment of the disease risk are all very important. For many diseases, the risk level will be higher if the crop rotation is very short, the crop variety is susceptible to the disease, the field or neighbouring fields have a history of the disease, and the weather conditions are moist with moderate temperatures. However, the only way to be sure about how much disease would have occurred in the field if you hadn t applied a fungicide is to have a check strip for comparison. That comparative information is really important to help you fine-tune your fungicide decisions in the future. One way of getting around putting in a whole check strip is just to turn the boom off for 10 to 15 feet at a few spots in the field, Turkington notes. That won t have a significant impact on the crop as a whole, but it will allow you to compare those spots where you didn t apply a fungicide to the rest of the field to see whether or not the fungicide had a significant impact on disease. Realistic expectations Growers may sometimes have unrealistic expectations about what a fungicide application can achieve. Perhaps they are comparing a fungicide application to a herbicide application; often if a herbicide application is well timed and it s an effective herbicide, they ll see complete weed death. But a fungicide application does not mean you ll have a completely disease-free crop, says Turkington. Instead, you should expect to have a significant reduction in the amount of disease and to maintain the productivity of that crop compared to an unprotected crop. This emphasizes the need for check strips or areas in the field. The level of control will depend in part on the disease issue. For instance, with Fusarium head blight, you can expect about 50 per cent control at best. So you re getting suppression; the disease will still be there but you ll reduce it significantly, he notes. Consequently, for managing Fusarium head blight, it is especially important to use a fungicide in combination with crop rotation and a resistant variety. With most leaf spot diseases, you can expect about 80 per cent control. Sometimes with good application technology, good timing and a good product, you can get over 90 per cent control. And with the rusts, sometimes you can get 90 to 95 per cent control with a well-timed application. If you spray a fungicide and find that you have a completely disease-free crop, then chances are the issue you had is not a disease, Turkington says, adding it is likely some other problem like herbicide injury, and as long as the injury is not too severe the crop will recover. We have seen this in research plots at Lacombe where a particular herbicide, when applied under cool conditions, caused symptoms that mimicked scald symptoms. Initially the barley plots looked awful as a result of the injury, but three weeks later they looked just fine, while the herbicide injury remained confined to the leaves that were emerged at the time of spraying. For more on fungicides, visit 14 SUPPLEMENT TO TOP CROP MANAGER (WEST) - APRIL 2015

15 A WHOLE SEASON OF WORK IS RIDING ON THIS MOMENT. NO PRESSURE. A lot of hard work, time and money go into growing cereals. So this is no time to take chances. Protect your investment with Caramba fungicide. It defends against profit-robbing leaf diseases and fusarium head blight (FHB) to help optimize grade and quality. So it should come as no surprise that Caramba is ranked the most preferred FHB fungicide by growers.* Ensure your grain measures up when it counts by visiting agsolutions.ca/caramba or call AgSolutions Customer Care at BASF (2273). *Source: Stratus, 2013 Always read and follow label directions. AgSolutions is a registered trade-mark of BASF Corporation; CARAMBA is a registered trade-mark of BASF Agro B.V.; all used with permission by BASF Canada Inc. CARAMBA fungicide should be used in a preventative disease control program BASF Canada Inc.

16 Tested in the lab. Proven in the field. Trusted by thousands of Canadian growers. It s no wonder more and more growers are choosing AgCelence -branded fungicides, including new Priaxor, Twinline, Headline and Insure Cereal seed treatment. They re the only ones proven to control disease, increase growth efficiency and better manage minor stress.* It all adds up to increased yield potential no matter what the season brings. So growers who trust fungicides with AgCelence benefits** don t just expect more. They get it. For more details, visit agsolutions.ca/agcelence or contact AgSolutions Customer Care at BASF (2273). *All comparisons are to untreated unless otherwise stated. **AgCelence benefits refer to products that contain the active ingredient pyraclostrobin. Always read and follow label directions. AgSolutions, and HEADLINE are registered trade-marks of BASF Corporation; AgCelence, INSURE, PRIAXOR, and TWINLINE are registered trade-marks of BASF SE; all used with permission of BASF Canada Inc. INSURE CEREAL fungicide seed treatment, HEADLINE, PRIAXOR and TWINLINE fungicides should be used in a preventative disease control program BASF Canada Inc.