Molecular Characterization of Indian Populations of Maize Cyst Nematode, Heterodera zeae using PCR-RFLP of Ribosomal DNA

The maize cyst nematode, Heterodera zeae, is a major nematode pest of maize, sugarcane, wheat, barley and other cereals. Six populations of H. zeae collected from Himachal Pradesh, Delhi, Bihar, Punjab and Haryana were analyzed by PCR-RFLP of Internal transcribed spacers (ITS 1 and 2) of rDNA for detecting intraspecies variation. PCR-RFLP analysis of ITS 1 and 2 with different restriction enzymes Alu1, Ava1, Dra 1, Hha1, Hind III, Hinf1, Msp1 and Rsa1 indicated that Samastipur population which is known to be a more virulent strain differed from all the other populations in having a distinct pattern with five of the eight enzymes studied. The UPGMA dendrogram also revealed that the Samstipur and Delhi populations were more variable and distant compared to the other four populations. The observed variation has implications in resistance breeding, regulatory and epidemiological aspects.