 This is the SugarBeat Report, bringing you the latest information from NDSU throughout the SugarBeat growing season. Now that the valley has received some notable rainfall, we're discussing the management of Circospa Leaf Spot in SugarBeat with Dr. Ashok Chanda, Extension SugarBeat Pathologist with the University of Minnesota and Northwest Research and Outreach Center in Crookston, Minnesota. Ashok, in a field, where exactly do you find Circospa Leaf Spot? So that's a great question, actually. Now if you think about Circospa, you know, most of the Circospa develops from the previously infected SugarBeat debris, you know, this is from the previous growing seasons. These fungus can survive in this debris for up to 22 months, right? So if you want to scout for Circospa, you should be looking at, you know, close to shelter belts or waterways, the fields that were adjacent to previously infected fields, you know. That's where the disease first develops and it's going to move into the fields. Typically, you see just about circular sparks which are about eighth of an inch and sometimes they may have reddish-purple or brownish border. If you're not sure, you can always send in a sample to our lab in Crookston for proper diagnosis. Are you finding any Circospa so far this season? Yes. Since 2022, the SugarBeat cooperatives are sampling leaves and these are randomly from growers' fields and from multiple locations and these samples are being analyzed at Dr. Nathan Wyatt's lab at ESDA facility in Fargo where they're using DNA-based assay for detecting Circospa in the leaf tissues. In 2022, 100% of the samples were positive for Circospa by July 6th. But so far this year, as of last week, about 78% of the fields were positive. But one thing to note is the Moorhead and Hillsport affected districts in 100% of the samples were positive. In terms of DIV values, right, we call these as daily infection values. These are slightly higher compared to 2022, which means the weather conditions are favorable for development of Circospa this year as well. Do the new CR Plus SugarBeat varieties require a fungicide application? I would say yes, based on what we see in the inoculative research trials at the Fox Home location. We believe that there is subset of Circospa types that are able to infect CR Plus varieties. But it's going to take some time before these populations can build up and can cause extensive damage in a growers' field. Compared to the traditional susceptible varieties, the CR Plus varieties will need fewer fungicide applications. But the most important thing is the early applications, such as the first and second applications are key in preventing the buildup of these isolates later in the season. Ashok, what are the main things growers need to be aware of in terms of fungicide applications? If you're thinking about fungicide like EBDC, you know, typically like a Mancozeb, this is the only fungicide that can be applied by itself. Something else needs to be tank mixed. Trizol fungicides, you know, Proline, Inspire XT, Provisol or Minerva, they have to be mixed with EBDC or another partner like a Copper. And if you're using tin-based fungicides such as Super 10, you can only use one or two times during the season. The second most thing is fungicide rotation. Except Mancozeb, you cannot use any other fungicide class, you know, for example trizol fungicide back to back, which means if you use trizol in spray one, then you have to wait until spray three, or if it's in spray two, not until spray four. And the other important thing with the fungicides is, you know, the spray volume, right? So most of the stochastra initially develops in the bottom portion of the canopy, you know, where the older leaves are, and then slowly it makes its way onto the top. So if you're using ground rigs, you know, or the tractors, at least 15 to 20 gallons should give you adequate coverage. But, you know, if the field is a little wet with the rain, you can do the aerial application, but they have to use at least five gallons. Spray intervals typically 10 to 12 days between the fungicide applications. But, you know, if there is a lot of rain, there should be a shorter interval up to, you know, seven to eight days. If you want to time your next fungicide application, you have to look at the daily infection values and also the amount of disease that you're seeing in the field. And so it'll be helpful for you to plan your next application. Thanks, Ashok. Our guest has been Ashok Chanda, Extension sugar beet pathologist with the University of Minnesota and Northwest Research and Outreach Center in Crookston, Minnesota. This is the Sugar Beet Report, bringing you the latest information from NDSU throughout the sugar beet growing season.