Optimization of conditions for callus induction and initial analysis of influencing factors for genetic transformation in foxtail millet.

At present,studies on foxtail millet tissue culture and genetic transformation are relatively less,the callus induction of different explants and its transformation efficiency is relatively low.This paper analyzed the formative factors of callus induction and optimized the inducing conditions by using different foxtail millet shoot apex as explants.The results showed that the optimized embryonic callus induction rate could be as high as 75.4% and the callus differentiation rate was about 15%.In addition,we transformed the callus using Agrobacterium tumefaciens-mediated method,and conducted GUS staining analysis.The result indicated that the transformation of callus GUS transient expression efficiency could be up to 22.3%.In this study,shoot tip explants could reduce the restriction of seasons and regions.The preliminary results showed that the optimized callus induction rate was greatly increased and the GUS transformation efficiency was also improved.This result has provided reference data for future studied on millet tissue culture and genetic transformation.