Rapid multiple shoot production from cotyledonary node explants of pea (Pisum sativum L.)

Multiple shoots were produced from cotyledonary node explants of pea (Pisum sativum L.) cultured on MS medium containing$1 mg l^{-1}$BAP. The number of buds formed could be increased by scraping the nodes before culture or by increasing the cytokinin concentration. However, cytokinin levels over$5 mg l^{-1}$increasingly produced shoots that were vitrified and difficult to root. With all the genotypes tested, developing buds were visible as soon as 5 days after culture and elongated shoots could be removed after 21 days. Histological studies indicated that the buds and shoots were formed from superficial layers of tissue. The efficiency of this regeneration system compared favorably with previously published methods. The rapid, genotype-independent, high frequency system described here may be of use in the production of transgenic pea plants.