The root knot nematode Meloidogyne ethiopica was recently discovered in Chile where it is broadly distributed. Host range includes tomato and grapevine, on which the nematode may cause severe losses and root damage. Species identification was based on traditional diagnostic characters, including perineal patterns and other morphological criteria as well as on isoenzymes and host range tests. In a preliminary study we investigated the rDNA genes of this species, in order to provide information on specific and subspecific grouping. Molecular identification based on polymerase chain reaction (PCR) was applied to determine the species identities of single females. A population associated to grapevine var. Pinot Noir proceeding from Casablanca (V Región) was used. For M. ethiopica identification, a pair of PCR primers was selected for its ability to amplify a single band of approx. 260 nucleotides from single females. The amplified product included a portion of the ITS1 and 5.8S regions. Blast analysis did not show high levels of similarity with rDNA sequences obtained from other Meloidogyne spp. deposited in Gen Bank. The closest sequence scored were U96304, AY438554, AY438555 and U96303, produced from M. incognita, M. arenaria, M. javanica and M. hapla, respectively. The degree of nucleotidic similarity was 88, 87, 87 and 80%, respectively. The rDNA region sequenced from M. ethiopica appeared as a useful starting point to design species-specific primers and probes for identification of single females and detection of the nematode from galls or plant roots.
Preliminary molecular characterization of rDNA genes from Meloidogyne ethiopica.
Rosso LC;Ciancio A
2005
Abstract
The root knot nematode Meloidogyne ethiopica was recently discovered in Chile where it is broadly distributed. Host range includes tomato and grapevine, on which the nematode may cause severe losses and root damage. Species identification was based on traditional diagnostic characters, including perineal patterns and other morphological criteria as well as on isoenzymes and host range tests. In a preliminary study we investigated the rDNA genes of this species, in order to provide information on specific and subspecific grouping. Molecular identification based on polymerase chain reaction (PCR) was applied to determine the species identities of single females. A population associated to grapevine var. Pinot Noir proceeding from Casablanca (V Región) was used. For M. ethiopica identification, a pair of PCR primers was selected for its ability to amplify a single band of approx. 260 nucleotides from single females. The amplified product included a portion of the ITS1 and 5.8S regions. Blast analysis did not show high levels of similarity with rDNA sequences obtained from other Meloidogyne spp. deposited in Gen Bank. The closest sequence scored were U96304, AY438554, AY438555 and U96303, produced from M. incognita, M. arenaria, M. javanica and M. hapla, respectively. The degree of nucleotidic similarity was 88, 87, 87 and 80%, respectively. The rDNA region sequenced from M. ethiopica appeared as a useful starting point to design species-specific primers and probes for identification of single females and detection of the nematode from galls or plant roots.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
