| Autor: |
Ramsey S. Lewis, David P. Eickholt |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
Crop Science. 53:2384-2391 |
| ISSN: |
0011-183X |
| Popis: |
Methods for rapid inbreeding are desirable for reducing the time required to complete a breed - ing cycle and to increase genetic gain per year. Constitutive expression of FLOWERING LOCUS T (FT) derived from Arabidopsis has previ - ously been shown to reduce generation time in tobacco ( Nicotiana tabacum L.) and other crop plants. Here, we used tobacco as a model sys - tem to investigate the utility of a modified sin- gle-seed descent (SSD) breeding method where transgenic expression of 35S :FT was used to reduce generation time during inbreeding. The transgene was maintained in hemizygous condi - tion during inbreeding, and null segregants were isolated in the F 4:5 generation to create nontrans - genic F 5:6 lines that were produced in nearly half the time that would have been required using conventional SSD. opportunities for selec - tion among 35S :FT plants during inbreeding were demonstrated by selecting for quantita - tive levels of resistance to the soil-borne patho - gen Phytophthora nicotianae. populations of selected lines exhibited significantly higher lev- els of resistance relative to random lines, greater frequencies of highly resistant genotypes, and lower frequencies of highly susceptible geno - types. The system outlined here could lead to more rapid commercialization of improved cul - tivars in crop species amenable to manipulation of flowering time via transgenic expression of FT-like genes. Strategies to enhance the fre - quency of favorable alleles in resulting popula - tions can be incorporated into the method. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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