Patent ID: 7863046

Claim:
A method of producing and maintaining a sustained totipotent embryogenic cell culture of a monocotyledonous plant comprising: (a) cultivating an explant of tissue from a monocotyledonous plant shoot tip to produce a sustained totipotent embryogenic cell culture, wherein the monocotyledonous plant is selected from the group consisting of Arundo spp. and Miscanthus spp.; (b) treating the sustained totipotent embryonic cell culture produced in step (a) with a cold temperature, wherein the cold temperature treatment is for a duration from about 60 days to about 360 days and comprises a temperature in a range from about 4 Â° C. to about 10 Â° C.; (c) removing the sustained totipotent embryogenic cell culture from the cold temperature treatment; and (d) cultivating the sustained totipotent embryogenic cell culture, whereby the sustained totipotent embryogenic cell culture of the monocotyledonous plant has an increased growth rate of the embryogenic cell mass as compared to a control.