I think I would. Personally, without knowing specifically what type of fungi we are dealing with, I would use a general purpose spray. I think I would go with Kocide (metalic copper) and spray it down well. Copper can be toxic if the levels get too high. However, under normal circumstances this isn't a problem. You might be able to find a general copper base fungicide at a local garden center. (I think Kocide comes in 50# bags!)
Based on the labels I can locate at the moment, a heavy dose for Kocide would be about .64 oz /gallon or 3.2 oz/5 gallons. If an acre has 43,560 square feet and the spray rate on the label is 150 gallons/acre, we end up with a gallon for about 290 square feet. With disease present, they suggest a heavy spray at 5-7 day intervals. I personally would mix a gallon and spray it on your beds letting it soak in well. This should burn off any fungi present on the surface and may help slightly with anything below the surface too. You might want to repeat this again in a week just to feel safe and then plant after that. Or, you might plant and mulch and apply the second spray to the mulch.
I often use Kocide this way in the early spring to spray the beds before emergence. This helps to kill off anything that wintered over and might affect the plants as they emerge through the mulch.
Which ever fungicide you use -if any- be sure to follow the label directions and go from there.
Disclaimer: I am not an expert. This is my best guess at trying to help somone solve a problem. I accept no responsibility for any suitability of these recommendations for any purpose and specifically refuse all liability for any results including any potential damages for the following of these suggestions.