Effects of n-butanol on barley microspore embryogenesis

Doubled haploid (DH) production is an efficient tool in barley breeding, but efficiency of DH methods is not consistent. Hence, the aim of this study was to study the effect of n-butanol application on DH barley plant production efficiency. Five elite cultivars of barley and thirteen breeding crosses with different microspore embryogenesis capacities were selected for n-butanol application in anther and isolated microspore cultures. Application of 0.1 % n-butanol after a mannitol stress treatment in anther culture significantly increased the number of embryos (up to almost twice) and green plants (from 1.7 to 3 times) in three low-responding cultivars: Albacete, Astoria and Majestic. No significant differences on microspore embryogenesis efficiency were observed in medium and high responding cultivars. The application of n-butanol treatment to isolated microspores from cold treated spikes in thirteen spring breeding crosses with a low or very low androgenetic response did not have a significant effect on the overall number of green plants. Nevertheless, an increase in the number of green plants was observed when 0.2 % n-butanol was applied in four out of seven low-responding crosses. Therefore, application of n-butanol could be routinely applied to anther cultures using mannitol treatment, in low-responding material. However, further studies are needed to determine optimal conditions in protocols using cold treatment and isolated microspore cultures.