EFFECTS OF PACLOBUTRAZOL ON THE GROWTH AND ANATOMY OF STEMS AND LEAVES OF <em>SYZYGIUM</em> <em>CAMPANULATUM</em>

Abstract

AHMAD NAZARUDIN, M. R., MOHD FAUZI, R. & TSAN, F. Y. 2007. Effects of paclobutrazol on the growth and anatomy of stems and leaves of Syzygium campanulatum. A study was conducted to determine the effects of paclobutrazol on plant height and leaf area of Syzygium campanulatum. The height of paclobutrazoltreated (1.25, 2.50 and 3.75 g l^–1) plants was found to be inhibited compared with non-treated plants. The treated plants had smaller leaves compared with those of non-treated plants, one month after treatment. However, there was no difference in plant height and leaf area between plants treated with different rates of paclobutrazol. Scanning electron micrographs of stems showed reduction in xylem thickness, while in the leaves, palisade and spongy parenchyma cells were more closely arranged in response to paclobutrazol. There was also an increase in palisade thickness of leaves of plants treated with 3.75 g l^–1 paclobutrazol. Paclobutrazol was found to effectively inhibit plant height and leaf expansion and alter the stem and leaf anatomy of S. campanulatum.