Silicon promotes shoot proliferation and shoot growth of Salvia splendens under salt stress in vitro

Abstract

Silicon (Si) is known to have beneficial effects on plants especially in monocots such as rice, wheat, and sugarcane. The objective of this study was to examine the effect of Si against NaCl on axillary shoot proliferation and shoot growth of in vitro of Salvia splendens 'Hot Jazz', one of the important floricultural plants. In vitro study was chosen because in such controlled environment the mechanism of Si alleviation can be clearly studied without any external hindrance. Nodal explants have been cultured on the MS medium supplemented with 3.0 mg center dot L-1 6-benzylaminopurine (BAP) and 0.5 mg center dot L-1 indole-3-acetic acid (IAA) with or without 50 or 100 mM NaCl as the salt stress source and 50 or 100 mg center dot L-1 K2SiO3 as the Si source. Salt stress exhibited strong retardation on growth parameters such as number and length of shoots and internodes, chlorophyll content, and the fresh and dry weights of shoots. At 50 mM NaCl both 50 and 100 mg center dot L-1 K2SiO3 helped to overcome the salt effect and maximized the plant growth. Though the Si gave tolerance and increased growth even in the 100 mM NaCl treatment, it was not as much effective as in the 50 mM NaCl treatment. In conclusion, these results put forward an experimental evidence for further studies of Si on salinity stress in ornamental plants.