DEVELOPMENT OF A SPECIES-SPECIFIC REVERSE PRIMER FOR THE MOLECULAR DIAGNOSTIC OF PRATYLENCHUS BRACHYURUS

Abstract

Machado, A. C. Z., L. C. C. B. Ferraz, and C. M. G. Oliveira. 2007. Development of a Species-Specific Reverse Primer for the Molecular Diagnostic of Pratylenchus brachyurus. Nematropica 37:249-257. A single step PCR using a species-specific reverse primer for the diagnosis of the economically important phytonematode Pratylenchus brachyurus was developed. The ITS-1 region of rDNA of P. brachyurus was amplified by PCR from genomic DNA. Sequence analysis indicated that the ITS-1 sequences were divergent between this species and other Pratylenchus species (P. coffeae, P. vulnus, and P. zeae). These sequence differences in the ITS-1 were used to synthesize a specific reverse primer to diagnose P. brachyurus. The primer was assessed for its reliability by screening 29 populations of P. brachyurus from Brazil, producing the expected fragment size (267 bp) for all populations tested. Furthermore, when challenged with closely related Pratylenchus species and general nematode communities typical of soil, no PCR product was amplified. Given its specificity, sensitivity and reliability, this diagnostic primer may be of great benefit to phytosanitary services related to agronomical crops.