Submitted to: Euphytica
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/23/2012
Publication Date: 3/10/2012
Publication URL: handle.nal.usda.gov/10113/58537
Citation: Prohens, J., Plazas, M., Raigon, M.D., Stommel, J.R., Vilanova, S. 2012. Characterization of interspecific hybrids and backcross generations from crosses between two cultivated eggplants (Solanum melongena and S. aethiopicum Kumba group)and implications for eggplant breeding. Euphytica. 186:517-538. Interpretive Summary: Common eggplant, Solanum melongena, is one of the most important vegetable crops in the world and has been the subject of considerable efforts in breeding for yield and quality. A related cultivated eggplant species, the scarlet eggplant (Solanum aethiopicum), has received little attention for genetic improvement. Using traditional breeding, molecular markers, and food chemical assays, we evaluated breeding behavior and fruit quality attributes of the scarlet eggplant in order to assess its value in eggplant breeding. Considerable diversity was evident within scarlet eggplant for plant morphology, fruit shape and size, and fruit constituents. The results indicate that breeding for improved scarlet eggplant is possible and that traits can be transferred between scarlet eggplant and common eggplant via breeding. These results will be of value to eggplant breeders and to specialty crop vegetable growers.
Technical Abstract: Common (Solanum melongena L.) and scarlet (S. aethiopicum L.) eggplants are cultivated for their fruits and form part of the same genepool. We have studied plant and fruit characteristics, pollen fertility and seed set, phenolics content, and fruit flesh browning in accessions of S. melongena and S. aethiopicum Kumba group, as well as interspecific hybrids between these species and first backcross generations to each parental species. Respective genotypes were also characterized with 7 polymorphic SSR markers. The results demonstrate that many differences exist for plant and fruit morphology among S. melongena, S. aethiopicum and the interspecific hybrids. The latter are very vigorous and generally intermediate between the two parents, except for fruit size which is smaller (and parthenocarpic due to a high pollen sterility) than those of any of the parents. Backcross progeny also exhibited morphological variation with moderate heritability values for the attributes evaluated. Variation for fruit size was present in the backcross generations but fruit were small resulting in little variation for fruit shape. Backcross plants with moderate fertility produced seeded fruits. Primary hybrids had fruit phenolics content similar to that of S. aethiopicum, the parent with lowest phenolics concentration, and were heterotic for fruit flesh browning. Backcross progeny were quite variable for both traits. SSR markers did not reveal segregation distortion in the backcross generations for these interspecific hybrids. The results demonstrate that generations derived from sexual interspecific hybridization can be a powerful tool for S. melongena and S. aethiopicum Kumba group breeding.