title: Identification of markers tightly linked to tomato  yellow leaf curl disease and root-knot nematode resistance by multiplex PCR.
abstract: Seven different commercial F₁ hybrids and two F₂ populations were evaluated by multiplex PCR to identify plants that are homozygous or heterozygous for Ty-1 and Mi, which confer resistance to tomato yellow leaf curl disease and root-knot nematode, respectively. The Ty-1 and Mi markers were amplified by PCR and identified by digestion of the amplicons with the TaqI enzyme. The hybrids E13 and 288 were found to be Ty/ty heterozygous plants with 398-, 303-, and 95-bp bands, and B08, 314, 198, and A10 were found to be ty/ty homozygous plants with a 398-bp band; whereas 098 did not give any PCR products. The hybrids E13 and 198 were found to be Mi/Mi homozygous plants with 570- and 180-bp bands, and 288 and A10 were found to be Mi/mi heterozygous plants, with 750-, 570- and 180-bp bands, and B08, 109 and 314 were found to be mi/mi homozygous plants with only a 750-bp band. We additionally developed a multiplex PCR technique for JB-1 and Mi, which confer resistance to tomato yellow leaf curl disease and root-knot nematode. The JB-1 marker identified the genotype of the Ty gene, and the plants that produced the 400-bp band were ty/ty homozygous plants, whereas the plants that produced 400- and 500-bp bands were resistant to tomato yellow leaf curl disease. We conclude that multiplex PCRs can be used to reproducibly and efficiently detect these resistance genes.
authors.affiliation: College of Horticulture, Northwest A & F University, Key Laboratory of Horticultural Plant Germplasm Resources Utilization in Northwest, Yangling Shaanxi, P.R. China. shuxiachen@nwsuaf.edu.cn
authors.forename: S X
authors.initials: SX
authors.lastname: Chen
authors.forename: J N
authors.initials: JN
authors.lastname: Du
authors.forename: L N
authors.initials: LN
authors.lastname: Hao
authors.forename: C Y
authors.initials: CY
authors.lastname: Wang
authors.forename: Q
authors.initials: Q
authors.lastname: Chen
authors.forename: Y X
authors.initials: YX
authors.lastname: Chang
mesh_terms: D000818:Animals; D003433:Crosses, Genetic; D017931:DNA Primers; D004262:DNA Restriction Enzymes; D060467:Disease Resistance / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics; D008040:Genetic Linkage; D005819:Genetic Markers; D006824:Hybridization, Genetic; D018551:Solanum lycopersicum / Q000235:genetics* / Q000276:immunology / Q000469:parasitology / Q000821:virology; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D009348:Nematoda / Q000502:physiology*; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology / Q000469:parasitology* / Q000821:virology*; D018517:Plant Roots / Q000469:parasitology; D011110:Polymorphism, Genetic
chemical_list: D017931:DNA Primers; D005819:Genetic Markers; D004262:DNA Restriction Enzymes