Title: Heritability of early blight resistance in a Lycopersicon esculentum x Lycopersicon hirsutum cross estimated by correlation between parent and progeny
Abstract:Abstract Sixteen‐hundred BC 1 plants of a cross between an early blight (EB) susceptible tomato ( Lycopersicon esculentum Mill.) breeding line (‘NC84173’ maternal and recurrent parent) and a resistant...Abstract Sixteen‐hundred BC 1 plants of a cross between an early blight (EB) susceptible tomato ( Lycopersicon esculentum Mill.) breeding line (‘NC84173’ maternal and recurrent parent) and a resistant accession (‘PI126445’) of the tomato wild species Lycopersicon hirsutum Humb. and Bonpl. were grown in a field in 1998. This population was segregating (among other traits) for growth habit, self‐incompatibility and earliness in maturity. To eliminate confounding effects of these factors on disease evaluation and h 2 estimation, plants that were self‐incompatible, indeterminate and/or late‐maturing were eliminated. The remaining plants (146), which were self‐compatible and determinate (sp./sp.) in growth habit, with early‐ to mid‐season maturity, were evaluated for EB resistance and self‐pollinated to produce BC 1 S 1 seed. The 146 BC 1 S 1 progeny families, consisting of 30 plants per family, were grown in a replicated field trial in 1999 and evaluated for EB resistance and plant maturity. For each of the 146 BC 1 plants and corresponding BC 1 families, the area under the disease progress curve (AUDPC) and final disease severity (final percentage defoliation) were determined and used to measure disease resistance. The distributions of the AUDPC and final percentage defoliation values in the BC 1 and BC 1 S 1 generations indicated that resistance from ‘PI126445’ was quantitative in nature. Estimates of h 2 for EB resistance, computed by correlation between BC 1 S 1 progeny family means and BC 1 individual plant values, ranged from 0.69 to 0.70, indicating that EB resistance of ‘P1126445’ was heritable. Across BC 1 S 1 families, a small, but significant, negative correlation (r = ‐0.26, P < 0.01) was observed between disease resistance and earliness in maturity. However, several BC 1 S 1 families were identified with considerable EB resistance and reasonably early maturity. These families should be useful for the development of commercially acceptable EB‐resistant tomato lines.Read More
Publication Year: 2001
Publication Date: 2001-04-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 24
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot