Comparison of six anther culture methods for the production of doubled haploids in eggplant (Solanum melongena L.)

Eggplant (Solanum melongena L.) is one of the most produced and high value vegetable crop in the world. Hybrid breeding toward high yielding variety of eggplants with many interesting traits are needed. To produce hybrid variety, production of pure lines as parents are needed. Pure lines in doubled haploid (DH) form can be produced through anther culture. The purpose of this study was to compare six anther culture methods to determine the most effective method to produce in vitro androgenic regenerated plants in eggplant. Anther culture methods used were 4 existing methods (DDV, TAS, ARI, and VUR), and two new method modified from ARI dan VUR, respectively. The anther donor plant genotypes used were Mustang F1 (long purple), Hitavi F1 (long green), and Provita F1 (striated round green) eggplant varieties. The result showed that androgenesis through the direct embryogenesis process in eggplant was still genotype dependent and the heat shock treatment at 35 °C is basically required, but the duration between 2 and 8 days were not significantly different to stimulate microspore embryogenesis. Modification 1 method was found as the most effective method as indicated by the fastest embryo initiation time, the highest percentage of anther producing embryo, the highest percentage of embryogenesis, the highest percentage of regeneration and the highest efficiency of anther culture. Ploidy level analysis by flow cytometry revealed the ploidy status of regenerants. Rate of spontaneous DH plant formation was 25.9%. The ploidy of regenerants has been validated by anatomy and plant morphology observations.