Objective To investigate the factors significantly affecting the shoot buds regeneration of Carthamus tinctorius from Jimsar （CTJ）. Methods Through tissue culture experiments, the influences of culture temperature, illuminance, relative humidity, explants type, seedlings age, and plant growth regulators added in culture media on in vitro regeneration of CTJ were investigated. Results The culture temperature was set at 24 ℃ in daytime and 16 ℃ at night, illuminance at 9000 lx, and 60% relative humidity were suitable for CTJ regeneration. Cotyledons excised from 6-8 d old seedlings were more responsive than even-aged euphyll, hypocotyl, and root explants because of inducing adventitious buds. The highest percentage of regenerated shoots （79. 1%） with about five adventitious buds per responding explant was obtained from MS basal medium containing 12.0 mg/LTDZ, 2.5 mg/L IBA, and 1.5 mg/L 2-ip （No. 14 medium）. Regenerated shoot buds （80%） could elongate successfully after 1-2 weeks transferred to shoot elongation medium. Conclusion Suitable factors of shoot buds regeneration for CTJ were determined. It may also make a useful reference for regeneration researches of other C. tinctorius varieties in China.
Background: Safflower regeneration through tissue culture has long been limited to low frequency and lack of an efficient protocol that suitable for most safflower cultivars. In past decades, researches had been carried out to investigate safflower regeneration through tissue culture and great progress had been made. Objective: To investigate factors that affect safflower regeneration through tissue culture principally. Methods: This article summarized available literatures about advancements in safflower regeneration, especially discussed factors affecting safflower tissue culture in detail. Results: Safflower regeneration was fairly hard than other congeneric plants, such as chrysanthemum. The genotype, seedling age, type of explants, medium components, plant growth regulators and other additives all had specific influences on safflower tissue culture. More deepgoing researches need to be undertaken to establish an effective safflower regeneration system.
