PLANT PHYSIOLOGY , Vol 103, Issue 4 1339-1346, Copyright © 1993 by American Society of Plant Biologists
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DEVELOPMENT AND GROWTH REGULATION |
Sorbitol as the Primary Carbon Source for the Growth of Embryogenic Callus of Maize
B. Swedlund and R. D. Locy
Agridyne Technologies, Inc., 417 Wakara Way, Salt Lake City, Utah 84108 (B.S.)
The effects of various carbon sources on initiation and maintenance of
embryogenic callus of maize (Zea mays L.) and on the regeneration of plants
from embryogenic callus were studied. Growth of embryogenic callus tissue
on media containing sucrose was typified by the subsequent growth of both
embryogenic (regenerable) and nonembryogenic (nonregenerable) callus.
Growth of embryogenic callus on sorbitol was unique among the carbon
sources tested in that sorbitol supported the subsequent growth of only
embryogenic callus. Further experiments demonstrated that embryogenic
callus grown on sorbitol had a greater regenerative capacity (more plants
produced per gram fresh weight of callus) than callus grown on sucrose.
Sorbitol dehydrogenase was detected in embryogenic callus of maize at a
specific activity roughly equivalent to that found in zygotic embryos of
developing seeds. Nonembryogenic callus did not contain significant levels
of sorbitol dehydrogenase activity.