David Owens, Extension Entomologist, owensd@udel.edu
There was less guessing activity on last week’s pest challenge. Remember, you cannot win Guess The Pest if you do not enter. The disease on last week’s melon transplants may have been seen earlier in the year, but conditions no longer favor it.
This from Jill:
Here’s a sample of watermelon with Pseudomonas leaf spot, caused by Pseudomonas spp. Not to be confused with bacterial fruit blotch–another, more severe, bacterial disease. This disease has tricky symptoms in watermelon, because we’re used to seeing angular leaf lesions with a bacterial disease in cucurbits, but these lesions are more circular. Cool, wet weather favors this pathogen, and it generally isn’t much of an issue after plants are moved into the field unless cool, rainy weather persists.
Here’s a sample of watermelon with Pseudomonas leaf spot, caused by Pseudomonas spp.