Co-Authors:
Zaffryar, S., Department of Ornamental Horticulture, Volcani Center, Bet Dagan 50250, Israel
Zimerman, B., Department of Ornamental Horticulture, Volcani Center, Bet Dagan 50250, Israel
Abu-Abied, M., Department of Ornamental Horticulture, Volcani Center, Bet Dagan 50250, Israel
Belausov, E., Department of Ornamental Horticulture, Volcani Center, Bet Dagan 50250, Israel
Lurya, G., Agricultural Extension Service, Ministry of Agriculture and Rural Development, Bet Dagan, Israel
Vainstein, A., Institute of Plant Sciences and Genetics in Agriculture, Faculty of Agricultural, Food, and Environmental Quality Sciences, Hebrew University of Jerusalem, Rehovot, Israel
Kamenetsky, R., Department of Ornamental Horticulture, Volcani Center, Bet Dagan 50250, Israel
Sadot, E., Department of Ornamental Horticulture, Volcani Center, Bet Dagan 50250, Israel
Abstract:
Narcissus tazetta is one of the major geophyte crops worldwide, but little is known about its cell biology. The narcissus storage organ was studied by monitoring scale cell biology during the growth stage and dormancy, and it was found that amyloplasts gradually increased in size and reached a maximum at dormancy. In parallel, microtubules changed their organisation: during the growth phase (February to March) they were oblique; during April and May, microtubules formed a network with round "holes"; by late June and the beginning of July, when dormancy started, they were organised in parallel arrays. The holes formed in the microtubule array corresponded to amyloplasts. A closer look showed that during a short time window, while the plants were preparing for dormancy, the microtubules surrounded the amyloplasts. In vitro reconfirmation of this phenomenon was obtained when fluorescent bovine brain microtubules enwrapped isolated amyloplasts that had been purified between April and July but not those purified between January and March. Interestingly, protease treatment of amyloplasts did not completely prevent binding of microtubules, which suggests the existence of a protease-resistant factor that docks microtubules to the outer membrane of amyloplasts. © 2007 Springer-Verlag.