Effects of genotypes and medium on callus induction of proso millet derived from anther culture

Proso millet is a promising species for rich nutrition and drought tolerance. Factors influencing anther-derived callus induction efficiency were investigated when microspores of anthers taken at the late-uninucleate to early- binucleate stage were used as explants. The results indicate that callus induction is strongly affected by genotype. Several highly responsive cultivars of proso millet with desired traits have been identified that could be directly used in crop improvement by breeding. Cold pre-treatment of spikes for three weeks, followed by 32.5°C heat treatment for a short time significantly improved callus yield. Moreover, W14 basal medium and a combination of 60 g/L sucrose with 60 g/L maltose as carbon source were optimal for anther culture of proso millet in this study. To our knowledge, this is the first report on successful regeneration of plants from pollen-derived callus in proso millet for use as a source to accelerate breeding programs.   Key words: Proso millet, temperature, medium, genotype, carbohydrate.