Abstract
Progressively higher concentrations of Paclobutrazol-markedly reduced germination of Valencia sweet orange (Citrus sinensis (L.) Osbeck) seed and induced significant changes in the morphology, growth, and development of roots of Valencia seedlings and rough lemon (C. limon (L.) Burm. f.) leaves. Threshold concentrations for significant visible effect to radical change ranged from 103 to 105 ppm (2.84×10−4 to 2.84×10−2 M) (ai). Initial change was readily evident in reduced lateral and fibrous root development at the lower concentrations (103 ppm). Higher concentrations (105 ppm) resulted in no secondary root formation and progressive basal enlargement terminating in a bulbouslike apex of the primary root. Lack of secondary roots suggests disruption in the pericycle or severe inhibition of meristematic initial cells. Root system changes were not visibly indicated in shoot growth other than strong inhibition of extensions.
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Bausher, M.G., Yelenosky, G. Morphological changes incitrus associated with relatively high concentrations of paclobutrazol. J Plant Growth Regul 5, 139–147 (1987). https://doi.org/10.1007/BF02087182
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DOI: https://doi.org/10.1007/BF02087182