Detection of Meloidogyne enterolobii in potatoes in South Africa and phylogenetic analysis based on intergenic region and the mitochondrial DNA sequences

摘要

Root-knot nematodes (Meloidogyne spp.) are a major problem facing crop production globally includingpotatoes. During the 2011/2012 potato growing season, root-knot nematode infested potato tuberswere obtained from different potato growing regions in South Africa for identification of Meloidogynespp. Using the intergenic region of the ribosomal DNA (IGS-rDNA) together with the region between thecytochrome oxidase small subunit II (COII) and the 16S rRNA gene in the mitochondrial DNA (mtDNA),five of the 78 composite samples received produced amplicon sizes of 705bp for COII and 780bp forIGS typical of M. enterolobii. These five samples were from the KwaZulu-Natal potato producing region.Nucleotide sequencing and phylogenetic analysis of the COII and IGS fragment showed that the fiveMeloidogyne populations were 100% similar and they clustered closely with those of M. enterolobii inthe GenBank database. The high damage potential of resistance-breaking populations of Meloidogynespecies is a threat to profitable potato production and will require effective pest managementprogrammes to be put in place.