THE SCREENING OF SEVERAL MOLDAVIAN TOMATO CULTIVARS FOR IDENTIFICATION OF MI-NEMATODE RESISTANCE GENE

Twenty two tomato cultivars grown in the Republic of Moldova were screened for resistance to root-knot nematode by molecular marker analysis and nematode bioassay. DNA based test and nematode bioassay were used to determine the presence of the root-knot nematode resistance gene Mi in these tomato cultivars. PCR product digestion with Taq I enzyme was performed to distinguish the homozygous and the heterozygous state of a particular allele at the Mi locus. One tomato line (348-III-2) was identified as homozygous resistant for the Mi gene, one variety (Djina) and two lines (35-IX-1, 351-IV-1) as heterozygous. The rest of the tomato genotypes tested were homozygous for the susceptible allele. Nematode bioassays were in agreement with the molecular marker analysis. This screening represents the first study of resistance to root-knot nematodes of tomatoes cultivated in the Republic of Moldova.