Blight, early seedlings died off

About 3 - 4 weeks ago I planted spinach, arugula, mesclun lettuce mix, radishes and brocoli rabe. I live in W. Concord MA. They all came up fast and strong but then the spinich wilted and died, then the arugula and now the radishes! These were planted in three 4' x 4' raised beds (boxed in). The lettuce is still fine and the rabe is in another box and is fine. Note the spinach and arugula are in the same box.

I've had spinach do this before with a fall crop but never with arugula and especially radishes.