Immuno-pathotyping of Karnal bunt (Tilletia indica) isolates of wheat using anti-mycelial antibodies.

Two types of polyclonal antibodies raised against whole lyophilized (LMA) and fractionated mycelial antigen (FMA) of most virulent, Pantnagar isolate of T. indica were used for the development of immunoassay systems, viz. dot immuno-binding assay (DIBA) and indirect enzyme linked immuno-sorbent assay (ELISA) procedures. The immuno-assays were developed by performing antigen concentration kinetics and antibody dilution curves analyses. These assays were employed for immuno-analysis of diversity amongst KB pathogen based on antibodies reactivity pattern and subsequently categorization into distinct sero-groups. The reactivity of two polyclonal antibodies was tested with 15 (P1-P15) isolates of T. indica. When anti-LMA antibodies were tested, four serologically distinct groups were formed based on percent reactivity (>75%, highly reactive; 60-75%; moderately reactive, <50-25%; low reactive and <25%, non-reactive). However, when anti-FMA antibodies were used, two distinct sero-groups were formed based on reactivity patterns (group I, highly reactive P1, P3, P4, P11 and P13, group II, less reactive P2, P4, P5, P6, P7, P8, P9, P10, P12, P14 and P15).