Effect of genotypical factors on the effectiveness of anther culture in eggplant (Solanum melongena L.)

Abstract

The aim of this study was to determine the androgenic capacity of some eggplant (Solanum melongena L.) varieties and breeding lines, and to establish the effectiveness of androgenesis induction in the less responsive genotypes by crossing with more responsive genotypes that have a high ability for haploid embryo formation. Flower buds containing greenish-yellow anthers were collected when the microspores were at the late uninucleate stage, which is equivalent to a bud size where petals are not visible. The anthers were kept in the dark at 35 degrees C for 8 days, then incubated with a 12 h light period at 25 degrees C for 4 days on C medium, and then transferred to solid R medium, supplemented with 30 g/L sucrose and 0.1 mg/L kinetin. Topan, Halep Karasi, and Teorem F-1 varieties and 2 breeding lines [Vd-1 and Vd-2 (LS 2346)] that have a tolerance to Verticillium dahliae Kleb. were used as the plant materials during the first part of the study. Haploid embryos were obtained from Topan and Halep Karasi at the rate of 4.16% and 2.63%, respectively. The responses of Topan and Halep Karasi eggplant varieties to the anther culture were better than those of the Teorem F-1 cultivar and the Vd-1 and Vd-2 lines. Because of their responses to anther culture, the Topan and Halep Karasi varieties were used as donor parents, and they were crossed with the other 3 genotypes (Teorem F-1, Vd-1, and Vd-2) reciprocally. Gametic embryogenesis among hybrids was only obtained from the Topan x Teorem F-1, and Teorem F-1 x Topan combinations (0.87% and 2.57%, respectively). Development of the haploid embryos and plant formation occurred at the rates of 0.69% and 2.57%, respectively. This study revealed that the effectiveness of androgenesis in eggplant strongly depended on genotypes. This crossing technique could be useful for increasing the opportunity for haploid embryogenesis from genotypes that are unlikely to form haploid embryos, and crossing between the fair-responsive and poor/nonresponsive genotypes could be a good system for qualifying androgenic response in eggplant.