DETECTION AND CHARACTERIZATION OF MELOIDOGYNE SPECIES ASSOCIATED WITH PEPPER IN INDIAN PUNJAB

Abstract

A survey in the Central and Western agro climatic zones of pepper-growing areas of the Indian Punjab was conducted to identify and characterize species of root-knot nematode (RKN) infecting the pepper crop. Morphological, morphometric, and DNA sequence analysis were used to identify the nematodes. Soil and root samples were collected from farmer’s fields and single egg mass progenies were maintained for identification and characterization. Progenies were identified by morphological studies and then confirmed by PCR amplification of DNA using species-specific SCAR (sequence characterized amplified region) primers, cloning, sequencing, and NCBI-BLASTn analysis of the target product. Results showed a mixed incidence of M. incognita and M. javanica in the Central agro climatic zone, whereas only M. incognita was detected in the Western agro climatic zone. The present study revealed that M. incognita and M. javanica are the main root-knot species infecting pepper in these regions of the Punjab. Phylogenetic analysis showed that SCAR sequences obtained in the present study were grouped closely with SCAR sequences for the respective Meloidogyne species identified from other parts of the world, emphasizing the reliability of the species-specific SCAR markers for quick detection of root-knot species with PCR assays.