In cleistogamous plants, growing on agricultural lands that are regularly sprayed with insecticides, fertilisation and seed formation goes on undisturbed. Give one reason.

Cleistogamous plants which have fully closed flowers. As the flowers are closed the reproductive organs of the flowers too are closed, i.e., unexposed to environment. So in Cleistogamous plants their reproductive organs are not free and are fused and are not exposed to environment so they remain undisturbed of the insecticide fertilisers and seed formation is outside environment.