Effects of Short-term Red Radiation and Choline Compounds on Cytokinin Content, Chlorophyll Accumulation and Photomorphogenesis in Wheat Seedlings
- 77 Downloads
Effects of choline compounds (2-chloroethyltrimethylammonium chloride and 2-ethyltrimethylammonium chloride) as well as red radiation (R) pulse on the dynamics of cytokinin changes, growth and chlorophyll (a + b) accumulation were studied during the growth and greening of etiolated wheat seedlings (Triticum aestivum L., var. Mironovskaya-808). The seedlings were grown for 120 h in the dark and then exposed for 72 h to white light. Pre-treatment of caryopses with cholines and pre-irradiation of etiolated seedlings with R inhibited elongation of both coleoptile and first leaf; but the same factors accelerated these growth responses when seedlings were exposed to white light. Chlorophyll (Chl) accumulation and the first leaf appearance from coleoptile were accelerated by the pre-treatments as well. Far-red radiation (FR) reversed all effects of R but choline pre-treatment eliminated partly R/FR photoreversibility. Two compounds with high cytokinin activity (tested on a fresh weight basis by the bioassay with Amaranthus caudatus L.) were found in shoots and first leaves. One of them had Rf, UV absorbance spectrum and the biological activity similar to N6-(Δ2-isopentenyl)adenosine. Another cytokinin-like substance was not identified with the used standards. Stimulation of greening by R pulse and cholines was accompanied with accelerated accumulation of both cytokinin-like substances. We conclude that the influence of R and cholines on the concentration of substances with cytokinin activities detected in the leaves might be involved in the stimulation of Chl accumulation.
Key wordsCholine compounds Cytokinins Greening Growth Phytochrome Triticum aestivum L.
2-ethyltrimethylammonium chloride (choline chloride)
(2-chloroethyltrimethylammonium chloride (chlorocholine chloride)
chlorophyll (a + b)
Unable to display preview. Download preview PDF.
- Behringer, F.J., Davies, P.J., Reid, J.B. 1990Genetic analysis of the role of gibberellins in the red light inhibition of stem elongation in etiolated seedlingsPlant Physiol.94432439Google Scholar
- Briggs, W.R., Mosinger, E., Shafer, E. 1988Phytochrome regulation of greening in barley-effects on chlorophyll accumulationPlant Physiol.86435440Google Scholar
- Greef, J.A., Friderico, H. 1983Photomorphogenesis and HormonesShropshire, W.Mohr, H. eds. PhotomorphogenesisSpringer-VerlagBerlin, Heidelberg, New-York, Tokio401427Google Scholar
- Deeva, V.P. 1980Retardants as Regulators of Plant GrowthNauka TekhnikaMinskGoogle Scholar
- Evans, A., Smith, H. 1976Localization of phytochrome in etioplasts and its regulation in vitro of gibberellin levelsProc. Natl. Acad. Sci. USA.73138142Google Scholar
- Ford, M., Kasemir, H., Mohr, H. 1981The influence of phytochrome and kinetin on chlorophyll accumulation in mustard cotyledons. A two factor analysisBer. Dtsch. Bot. Ges.943541Google Scholar
- Kuznetsov, E.D., Vasilenko, V.F., Kreslavsky, V.D. 1992Stimulation effects of short-term red light and plant growth retardants on greening and formation of photosynthetic apparatusPlant Physiol. Biochem.30559564Google Scholar
- Ladygin, V.G., Shirshikova, G.N., Semenova, G.A., Kreslavski, V.D. 2002Effect of choline chloride on chloroplast ultrastructure and cell growth of green alga Chlamydomonas reingardtiiBiophizika46256264Google Scholar
- Lichtenthaler, H.K, Wellburn, A.R. 1983Determination of total carotenoids and chlorophylls a and b of leaf extracts in different solventsBiochem. Soc. Trans.11591592Google Scholar
- Miura, G.A., Shih, T.M. 1984Cholinergic constituents in plants: characterization and distribution of acetylcholine and cholinePhysiol. Plant.61417421Google Scholar
- Mohr H. 1984. Phytochrome and chloroplast development. In: Baker N.R. and Barber J. (eds.) Chloroplast Biogenesis. Elsevier Science Publishers B.V., pp. 307–345.Google Scholar
- Quail, P.H. 1994Photosensory perception and signal transduction in plantsCurr. Opin. Genet. Dev.661328Google Scholar
- Smith, H., Whitelam, G. 1990Phytochrome is a family of photoreceptors with multiple physiological rolesPlant Cell Environ.130695707Google Scholar
- Vasilenko, V.F., Kreslavski, V.D., Kuznetsov, E.D. 1991Chlorocholine chloride as a modifier of number of phytochrome-controlled processes of growth and photosynthesisDokl. Acad. Nauk SSSR31615121514Google Scholar