Genotypes-Independent Optimization of Nitrogen Supply for Isolated Microspore Cultures in Barley

To establish a high-efficiency system of isolated microspore culture for different barley genotypes, we investigated the effects of nitrogen sources and concentrations on callus induction and plant regeneration in different barley genotypes. The results showed that the organic nitrogen sources greatly increased the callus induction, and the great reduction of total nitrogen sources would significantly decrease the callus induction. And the further optimization experiments revealed that the increasing of organic nitrogen sources was much important in callus induction while it seemed different in plant regeneration. Based on the great effects of organic nitrogen on callus induction, the medium of N6-ANO1/4-2000 might be the best choice for the microspore culture system. In addition, the phylogenetic analysis indicated that there were clear differences of genetic backgrounds among these barley genotypes, and it also suggested that this medium for microspore culture had widespread utilization in different barley genotypes.