COMPARATIVE EFFICACY OF BORIC ACID AND PENCYCURON FOR MANAGEMENT OF BLACK SCURF OF POTATO

Black scurf of potato caused by Rhizoctonia solani is an important disease of potato throughout the world. Disease infected seed tubers are the major source of infection. Boric acid and pencycuron are the two chemicals which are frequently used by Indian farmers to control the disease. Application of boric acid to seed tubers is recommended as dip seed treatment prior to cold storage where as pencycuron can be applied to the sprouted tubers at planting. Since many farmers apply seed treatment to the sprouted tubers after its removal from cold stores prior to their planting in field, a comparison of efficacy and cost of seed treatment with boric acid and pencycuron applied by different methods to the sprouted tubers at planting, was carried out in field trials during 2009-10 and 2010-11. The study revealed that seed tuber treatment with pencycuron @ 0.057% a.i. or boric acid (3%) as spray on the seed tubers prior to planting could control the disease effectively without affecting crop emergence and thus were efficient and economical options available for control of black scurf.