Q.Cucumber Leaves Are Getting Dried Out. Dying
My cucumber plants leaves start turning translucent in between the veins and then dies. Everything else is fine
Certified GKH Gardening Expert
Without seeing the rest of the plant, it looks to be overwatered, or the soil is infected. This can happen when trying to compensate for heat. It is necessary to let the soil dry out, thoroughly, down to about 2 or 3 inches between watering, even when it is warm.
Here are some articles that will help:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/edible/vegetables/cucumber/tips-for-growing-cucumbers.htm