Root malformation is the major hinder faced by carrot growers. Root knot nematodes, Meloiodogyne spp. acts as a prime cause for the carrot root malformation. Hence, an extensive random survey was conducted in different locations from leading carrot growing districts of Tamil Nadu viz., The Nilgiris, Dindigul, Erode and Krishnagiri districts for root knot nematodes parasitizing carrot, and their infestation was recorded everywhere except Erode. The compound microscopic images of posterior cuticular pattern of females collected from tropical and temperate ecosystems revealed the high dorsal arch and flattened ovoid shape, vindicating Meloidogyne incognita and M. hapla, respectively. The 560 bp amplicon 18S rDNA region of females from the tropical and temperate ecosystems of Tamil Nadu were greater than 98 per cent similar to M. incognita and M. hapla, respectively. The present study confirmed the parasitisation of M. incognita and M. hapla in carrots cultivated from tropical and temperat

Carrot, root knot nematodes, posterior cuticular pattern, polymerase chain reaction and Tamil Nadu