@article{oai:iwate-u.repo.nii.ac.jp:00009144, author = {Watanabe, Manabu and Suzuki, Akiara and Komori, Sadao and Bessho, Hideo}, issue = {1}, journal = {Journal of the Japanese Society for Horticultural Science}, month = {Jan}, note = {Seasonal changes of endogenous IAA and cytokinin concentrations in shoots of two columnar type cultivars, 'Maypole' and 'Tuscan', and a normal type apple tree, 'McIntosh', were compared by gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM).The IAA concentrations in both types were higher in June, when shoot growth was vigorous, than in July. However, distinct differences in the IAA concentrations between columnar and normal types were not found. Cytokinin concentrations, particularly zeatin riboside (ZR), in shoots were higher in columnar type trees than in the normal type during the whole growing season in June. These results suggest that the concentration of cytokinins, particularly ZR, in shoots may be related to the growth characteristics of columnar type trees.}, pages = {19--24}, title = {Comparison of Endogenous IAA and Cytokinins in Shoots of Columnar and Normal Type Apple Trees}, volume = {73}, year = {2004} }