Originally Posted by Nicolas Naranja

I worked for a plant physiologist a few years ago, and have a Master's in Agronomy, my expertise however is not bananas. However, plants in general respond to evaporative demand which is based on heat and humidity and if evaporative demand is high the stomata will close and the plants growth will cease. Another issue related to the UV light that you mentioned might very well have to do with photorespiration which is the wasteful evolution of carbon dioxide due to sunlight in C3 plants.