STUDIES ON CULTURE OF IMMATURE COTYLEDONS AND THEIR PROTOPLASTS OF PHASEOLUS AUREUS
Li Xue-bao, Xu Zhi-hong, Wei Zhi-ming, and Bai Yong-yan (National Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology, Academia Sinica, Shanghai 200032) Wuhan Institute of Botany, Academia Sinica, Wuhan 430074.
Immature cotyledons of mung bean (Phaseolus aureus) were cultured on B_5 medium supplemented with 0.2 mg/L 2,4-D, 1 mg/L NAA and 0.5-1mg/L BA, and the nodular calli were induced in two weeks. Shoot formation was initiated and plant regeneration was obtained after the calli were transferred MS medium containing 0.5 mg/L IAA, 2 mg/L BA, 0.5 mg/L KT and 0.5 mg/L ZT. Protoplasts isolated from immature cotyledons of mung bean were cultured in B_5, MS or KM 8 p liquid medium supplemented with 0.2mg/L 2,4-D, 0.5mg/L BA and 1 mg/L NAA, Sustained cell divisions resulted in formation of cell clusters and small calli in B_5 medium, with division frequency of 17%—29% at 10 days. The calli from the protoplasts became yellow-green and nodular on MSB agar me0ium containing 1 mg/L 2,4-D, 0.1—0.5 mg/L ZT, 3—5% mannitol and 560 mg L NaCl. Adventitious roots and green spots formed from protoplastderived calli on MSB medium with low concentration of phytohormone or without phytohormone.