Sentence:  Throughout the year pathologists receive numerous samples of yellow, creeping bentgrass or annual bluegrass ("Poa annua") from putting greens. In autumn or spring, superintendents sometimes suspect that yellow tuft ("Sclerophthora macrospora") or <WSD>yellow patch</WSD> ("Rhizoctonia cerealis") diseases are the problem. 
Meaning of the word marked with <WSD> tags:  A disease affecting several varieties of grasses, including bentgrasses, annual bluegrass, some perennial ryegrass and Kentucky bluegrass, which results in the development of yellow or brown rings.