caa a22 4500 397520700 CHVBK 20180308164631.0 cr unu---uuuuu 161202e199509 xx s 000 0 eng 10.1093/jxb/46.9.1085 doi (NATIONALLICENCE)oxford-10.1093/jxb/46.9.1085 Effect of the Rht3 dwarfing gene on dynamics of cell extension in wheat leaves, and its modification by gibberellic acid and paclobutrazol [Elektronische Daten] [C.L. Tonkinson, R.F. Lyndon, G.M. Arnold, J.R. Lenton] The second leaf of wheat was used as a model system to examine the effects of the Rht3 dwarfing gene on leaf growth. Compared to the rht3 wild type, the Rht3allele decreased final leaf length, surface area and dry mass by reducing the maximum growth rates, but without affecting growth duration. Gibberellic acid (GA3) increased final leaf length and maximum growth rate in the rht3 wild type, but was without effect on the Rht3 mutant, which is generally regarded as being non-responsive to gibberellin (GA). Paclobutrazol, an inhibitor of GA biosynthesis, decreased final leaf length and maximum growth rate in the rht3 wild type to values similar to those in the untreated Rht3 mutant. Neither GA3 nor paclobutrazol affected the duration of leaf growth. The decrease in leaf length was produced by reduction of cell length rather than cell number. The maximum relative elemental growth rate (REGR) for cell extension was essentially the same in all treatments, as was the time between the cells leaving the meristem and achieving maximum extension rate. The differences between the genotypes and treatments were all almost entirely due to differences in the time taken from the attainment of maximum REGR of cell extension to the cessation of extension. This was reflected in the length of the extension zone, which was approximately 6-8 per cent of final leaf length. The effects of the Rht3 allele, GA3 and paclobutrazol all appear to be on the processes which promote the cessation of cell elongation. © Oxford University Press RESEARCH PAPERS nationallicence Cell extension nationallicence gibberellin nationallicence leaf growth nationallicence Rht3 gene nationallicence Triticum nationallicence wheat nationallicence Tonkinson C.L. Institute of Cell and Molecular Biology, University of Edinburgh Mayfield Road, Edinburgh EH93JH, UK aut Lyndon R.F. Institute of Cell and Molecular Biology, University of Edinburgh Mayfield Road, Edinburgh EH93JH, UK aut Arnold G.M. IACR, Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol Bristol BS18 9AF, UK aut Lenton J.R. IACR, Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol Bristol BS18 9AF, UK aut Journal of Experimental Botany Oxford University Press 46/9(1995-09), 1085-1092 0022-0957 46:9<1085 1995 46 exbotj https://doi.org/10.1093/jxb/46.9.1085 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jxb/46.9.1085 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tonkinson C.L. Institute of Cell and Molecular Biology, University of Edinburgh Mayfield Road, Edinburgh EH93JH, UK aut NATIONALLICENCE 700 1- Lyndon R.F. Institute of Cell and Molecular Biology, University of Edinburgh Mayfield Road, Edinburgh EH93JH, UK aut NATIONALLICENCE 700 1- Arnold G.M. IACR, Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol Bristol BS18 9AF, UK aut NATIONALLICENCE 700 1- Lenton J.R. IACR, Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol Bristol BS18 9AF, UK aut NATIONALLICENCE 773 0- Journal of Experimental Botany Oxford University Press 46/9(1995-09), 1085-1092 0022-0957 46:9<1085 1995 46 exbotj Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford