Seed germination and seedling growth in Solanaceous species to water stress under in vitro conditions

Abstract

A study on seed germination and seedling growth was conducted with five cultivars of Solanum melongena L. (cvs. Arka Nidhi, B.P.L.H.-1, Arka Neelakanth, Arka Keshav and Mattu Gulla) and a wild species Solanum macrocarpon L. under different levels of osmotic potential induced by polyethylene glycol (PEG 8000). Germination declined progressively in response to decreasing (more negative) water potential, and no germination was found beyond -0.4MPa in any of the cultivars/species. Except for cvs. Arka Nidhi, B.P.L.H.-1 and Mattu Gulla, no germination was seen at -0.4MPa Cultivar Arka Neelkanth failed to germinate under any of the osmotic concentrations tested. Response in term of root growth was better in Arka Neelkanth, followed by Arka Nidhi and B.P.L.H.-1, upto transfer from different levels of osmotic potential to Control (0MPa). Germination of primed seeds within 24h indicates that many processes leading to normal germination would have been completed during the priming process itself. In contrast to germination, growth extension in radicle was less sensitive to water stress.