Novel Methodology for Delivering Putrescine into the Apple Explants Using Hormone Anchored Nanotube

Abstract Multi wall carbon nanotubes have been successfully exploited as growth regulator for manipulation of plant development. Also, nanoparticles are gradually involved in target delivery systems as the carrier of hormones. Polyamines and their derivations play crucial roles in plant growth and development. Take the mentioned subjects into consideration, putrescine anchored carbon nanotube which had been labeled with fluorescein was synthetized in this study. A set of physiological and morphological parameters were assessed in an attempt to examine the usage potential of de novo synthetized nanotube in terms of plant in-vitro culture. For this purpose, the nanotube was applied onto the in-vitro plantlets of Malus niedzwetzkyana in three concentrations (0, 50 and 100 mg/l). Localization of the nanotube in the plantlets was accomplished using fluorescence microscopy. Bio-imaging of tissues indicated the existence of nanotube in nearly all studied organs. Application of the nanotube at both concentrations (50 and 100 mg/l) increased the rate of leaf formation and speeding up the plastochron. Also, proliferation of the plantlets was enhanced using the nanotube. The levels of the photosynthetic pigments, including chlorophyll a, b and carotenoids increased following application of the nanotube. Glutathione peroxidase activity was significantly affected by the nanotube. However, polyphenol oxidase and peroxidase were not influenced by the nanotube. Stomatal density was increased by treatment of the plantlets with the nanotube. Representing geometrical transformation of shape as a thin plate spline revealed that the nanotube effectively increased longitudinally of stomata and changes their aspect ratio.