Localization of genes for bacterial canker resistance in Lycopersicon peruvianum using RFLPs

Area of Science:

• Plant Pathology
• Genetics
• Molecular Biology

Background:

• Bacterial canker, caused by Clavibacter michiganensis ssp. michiganensis, is a significant disease affecting tomato production.
• Understanding the genetic basis of resistance is crucial for developing resistant cultivars.

Purpose of the Study:

• To map the genetic loci conferring resistance to bacterial canker in *Lycopersicon peruvianum*.
• To investigate the inheritance pattern of bacterial canker resistance.

Main Methods:

• A backcross population was generated between resistant (*L. peruvianum* LA 2157) and susceptible (*L. peruvianum* LA 2172) accessions.
• Disease severity was scored using an ordinal scale.
• Segregation of resistance and RFLP markers was analyzed using the Kruskal-Wallis rank-sum test.

Main Results:

• Mapping of resistance was complicated by distorted segregation ratios and quantitative inheritance.
• Five chromosomal regions on chromosomes 1, 6, 7, 8, and 10 were identified as potentially harboring resistance genes.

Conclusions:

• The genetic control of bacterial canker resistance in *L. peruvianum* is complex, involving multiple loci.
• Further studies are needed to fine-map these resistance regions and identify the specific genes involved.