ISSN:
1432-2242
Keywords:
Tomato
;
Lycopersicon esculentum
;
Root knot nematode resistance
;
Meloidogyne
;
RFLP markers
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The Mi gene originating from the wild tomato species Lycopersicon peruvianum confers resistance to all major root knot nematodes (Meloidogyne spp.). This single dominant gene is located on chromosome 6 and is very closely linked to the acid phosphatase-1 (Aps-1) locus. Resistance to nematodes has been introgressed into various cultivars of the cultivated tomato (L. esculentum), in many cultivars along with the linked L. peruvianum Aps-1 1 allele. By using a pair of nearly isogenic lines differing in a small chromosomal region containing the Mi and Aps-1 loci, we have identified two RFLP markers, GP79 and H6A2c2, which are located in the introgressed L. peruvianum region. Analysis of a test panel of 51 L. esculentum genotypes of various origins indicated that GP79 is very tightly linked to the Mi gene and allows both homozygous and heterozygous nematode-resistant genotypes to be distinguished from susceptible genotypes, irrespective of their Aps-1 alleles. Marker H6A2c2 is linked to the Aps-1 locus and is capable of discriminating between the L. peruvianum Aps-1 1 allele and the L. esculentum Aps-1 3 and Aps-1 + alleles. In combination, these RFLP markers may provide a powerful tool in breeding tomatoes for nematode resistance.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00226734
