Explanation:

coffee cultivation was abandoned in sri lanka due to leaf rust disease which affects the leaf and fruit of coffee.Hemileia vastatrix is a fungus of the order Pucciniales (previously also known as Uredinales) that causes coffee leaf rust (CLR), a disease that is devastating to susceptible coffee plantations. Coffee serves as the obligate host of coffee rust, that is, the rust must have access to and come into physical contact with coffee (Coffea sp.) in order to survive.