Preliminary Study Of Light And Brassinolide On Cotton Embryogenic Callus

In this study,the effects of different light qualities and BRs on callus morphology and embryogenic callus induction in cotton were evaluated.Embryogenic callus formation was affected by cotton materials CCRI24.1 Red light treatments during the induction phase significantly promoted the formation of embryogenic calli,reaching 94.0%,and the differentiation period was reduced to 30 d compared with more than 60 d under white light conditions.Calli were of a moderate size and had moderate peroxidase,superoxidase dismutase,and catalase activity levels under red light conditions,which may maintain the balance between callus growth and differentiation.The highest total polyamine,spermidine,and spermine contents,and the lowest putrescine content,were detected during red light treatments.Additionally,endogenous auxin levels were significantly greater in red light-treated calli.The expression levels of the somatic embryogenesis marker genes AGAMOUS-like 15,LEAFY COTYLEDON1,LEAFY COTYLEDON2,BABY BOOM,and WUSCHEL were up-regulated under red light compared with white light conditions.2 The differentiation rate of embryogenic callus in cotton showed significant difference when BRZ was applied in the medium at different concentrations.With the increase of BRZ concentration 0-60nm,the differentiation rate of EC increased gradually.When BRZ concentration was 60nm,EC differentiation rate was the highest,reaching 89.6%.Transcription profiling analysis,physiological and biochemical experiment showed that the BR for cotton embryonic callus differentiation is needed,the appropriate concentration of BR could significantly promote the differentiation of embryonic callus.