 I'm Michael Vunch, I'm the plant pathologist here at the NDSU Carington Research Center and we do and we have for a long time done extensive fungicide testing for management of acyclicitoblite of chickpeas. Anyone who grows chickpeas or knows anyone who has grown chickpeas knows that acyclicitoblite is the major limiting factor for chickpea production and obviously under severe disease pressure can cause complete crop loss in chickpeas. Under more moderate disease pressure though it can also cause really severe losses not only in yield but also quality. So acyclicitoblite of course produces foliar lesions which reduce the ability of the plant to capture sunlight and convert that sunlight into sugars and food but it also produces stem lesions that can girdle the stem and keep the water from flowing up the plant, kill off the upper plant but beyond that it also causes pod lesions and the pod lesions are really a problem. When the disease develops very early in the pod development and the developing seeds inside there will often abort completely resulting in empty pods. When the disease develops a little bit later the seeds will still develop but they will often be smaller in size and in other cases and very often actually develop disease lesions on them and so they become necrotic and that seed discoloration is a major quality factor. Seed size is of course another quality factor so these pod lesions result in both seed size reductions and discoloration problems which both impact quality and can result in the chickpea crop being headed to an animal feed market rather than human consumption which drastically reduces the price. So management of acyclicitoblite is really critically important. Now over the years and I have been here, this is my 11th field season, I have worked with chickpea growers and crop advisors for almost the duration of that period and one of the recurring themes I hear over and over again is that such and such fungicide no longer works. Sometimes it's proline no longer works. Sometimes it's priaxer no longer works. But I hear this over and over and over again. Now the acyclicitoblite pathogen has developed resistance to the frac-11, the QOI are also known as strebilion fungicides. In which case the strebilion fungicides they really don't work. But what we find with proline and priaxer and these other fungicides that either have a triazole, frac-3 or an STHI, frac-7, mode of action is that when we use them the next year they work again. And so in this case fungicide resistance has not developed and indeed we haven't recorded it in our laboratory assays. Okay? Instead what's going on here is that under very high disease pressure the fungicide gets overwhelmed by the pathogen. Okay? And what we have found by analyzing all of our efficacy trial results, all the times we've ever tested fungicides for their efficacy in field trials from 2007 all the way through 2019 here in Carrington, out in Minot, over in Wilson, at the irrigated research site east of Wilson in Hoffland. What we find by analyzing all those data is that under low disease pressure you can use just about any registered fungicide. As the disease pressure increases the most effective fungicides still work to a certain point and at a certain point every fungicide gets overwhelmed and the fungicides really differ at the point at which they get overwhelmed. And what we find by plotting the disease pressure as recorded in the non-treater control relative to the yield gain conferred by the fungicide as the disease pressure increases the yield gain conferred by the fungicide keeps on increasing and increasing and increasing to a point. For proline the inflection point is a 50 on a 0-100 scale quantifying disease pressure in the non-treater control across the season. And then after that inflection point the yield conferred by the fungicide actually starts to drop as disease pressure increases. For Proaxer that inflection point is earlier at 44. For Verticin applied at 20 to 20.6 fluid ounces the high rate it's even earlier at 41. But with all of the fungicides for which we've done enough testing to rigorously look at the response of fungicide relative to disease pressure we see the same thing. Disease pressure as it increases will eventually overwhelm the fungicide. The most effective fungicides hang on longer the least effective fungicides fall off earlier. But we still come into this problem well what do you use when it's really cool and wet for an extended period and we're really worried about ascokytoblite. And what we have found really through just a stroke of luck is that back in 2015 we tested a tank mix of a contact fungicide chlorothalinol in this case bravo weather was the commercial formulation with proline so we mixed the two together and we applied that tank mix in this case sequentially all season long normally you would rotate but in these testing in these studies when we're testing efficacy we often apply the same product over and over and what we found there is that we got this drastic improvement in disease control and drastic improvement in yield so we kept on testing it we have now tested this tank mix 11 times every single time we have tested it whether it's here out in Williston or at an on farm site south of my not what we have found is that we consistently improved disease control and or yield and often the improvement is statistically significant and when we get to really high disease pressure is the only way to get a clean field of chickpeas and it's the only thing that doesn't get overwhelmed but the really the interesting part of this is that we're seeing the response even at low disease pressure across three field trials in which we had a lot of moderate pressure we average 750 pound yield gain from proline alone and an additional 800 pound yield gain when we added the bravo weather stick i.e. we more than double our response to the fungicide and under higher disease pressure we're seeing about a 400 to 450 pound on average yield gain from adding the bravo but that's not even the smallest part of it because we're able to produce very clean chickpeas which means we're able to get clean seeds without necrotic lesions and without the shriveled smaller seeds and so it's higher quality the big critical question that we're trying to address this year is do we have to use bravo weather stick bravo weather stick is only one of multiple formulations of chlorothalinol and unfortunately it happens to be the most expensive one and so we are testing this year ecuse 720 from and that corporation and praise from winfield united as alternatives and seeking to learn whether or not those can be utilized with equal success at this point we don't know our testing is focused on bravo weather stick but we hope to learn that for more information including the rate response what we have learned in rate response go to the end issue kerington website google end issue kerington click on plat pathology and scroll down to find the information on chickpeas you'll find a set of slides there that give you information on optimizing the employment of tank mixes with chlorothalinol ok thank you for your time behind me are our chickpea studies this year we have six acres of chickpea fungicide efficacy studies this year just like we did last year we do a lot of work on this on the subject thank you for your time