English

Abstract

Meloidogyne graminicola infect graminaceous plants but have lesser tendency to infect dicotyledonous plants. Meloidogyne incognita is a pest of dicots and occasionally infects cereals. Evolutionary adaptation of these root-knot nematodes to their preferred hosts might have led to variability in their gene/protein profile which could contribute to their differential behaviour outside and inside the different host crops. Polyclonal and monoclonal antibodies raised against several nematode species showed cross-reactivity to antigens with different molecular weights present in the whole body homogenate of M. incognita and M. graminicola J2. This variability in antigenicity may correspond to specific functions of these molecules in M. incognita and M. graminicola. Using proteomics approach possible amino acid sequence of those antigens was elucidated and showed sequence similarity with several proteins like signal recognition particle protein, galactose binding lectin, zinc finger motif, neurotransmitter gated ion channel, transmembrane protein, etc. from the genomic database of several nematode species. To investigate the function of the identified nematode genes, RNA interference could be used to reduce the expression of these selected genes and determine their importance for nematode development, survival or parasitism.   Key words: Antibodies, antigens, host recognition, secreted-excreted products, surface coat.