Some of my cucumber plants have leaves that are yellowing and curling, as shown in the pictures below.
It may be hard to tell from the pictures, but the leaves have small yellow spots on them, and have turned from a rich, deep green to a somewhat sickly yellow-green. They use to be flat. Now they curl.
The fruit is deformed too. It looks like the cucumber may have hit the side of the container and bounced, leading to the deformation.
These are Japanese cucumbers and are supposed to be slender and straight, not bent and bulging as seen here. (see UPDATE below)
I had to go out of town for a week and left the plants on a watering timer with drip watering. I'm not sure what the weather was like, but there was at least one hot day and some windy days. These cucumbers are in a 25-gallon fabric container filled with what was billed as raised-bed gardening soil.
EDITED TO ADD:
I should add that the blossoms no longer open fully and sometimes even turn gray and papery and fall off without even blooming.
I harvested the two cucumbers on the plants that were bulging. The issue appears to have been uneven pollination rather than disease. The slim part of the cucumber had no seeds. The bulging part had oodles of seeds. The taste of the cucumbers was quite good.