Abstract

                                Thirty three isolates of Fusarium udum obtained from pigeonpea (Cajanus cajan) plant showing wilt symptoms were collected from various states in India and tested for variability in Amplified Fragment Length Polymorphism (AFLP). AFLP analysis of 33 F. udum isolates using four primer combinations generated a total of 72 fragments with 68 being polymorphic (94.38 % polymorphism). Cluster and Principal Component Analysis had grouped Fusarium udum isolates collected from different parts of India into four races. Among the races identified, race 3 had maximum number of isolates grouped into it and its presence in five pigeonpea growing states of India whereas race 1 and 2 were present only in Karnataka and Andhra Pradesh. In Karnataka state all four races were observed indicating that varieties with horizontal resistance against all four races are important to combat this disease.

Key words : Amplified Fragment Length Polymorphism, Cajanus cajan, Fusarium udum.