Studies on Seed Germination, Plant Regeneration, and Soil Acclimatization of Nepeta binaloudensis Jamzad (Lamiaceae)

Abstract

Nepeta binaloudensis Jamzad is an Iranian endemic and rare plant species. This endangered species needs to be urgently protected due to excessive harvesting and habitat destruction. Nepeta species have played a crucial role in Iranian traditional medicine to treat disorders. Plant tissue culture can make a significant contribution to the conservation of endangered plants. In this study, an effort has been made for the efficient regeneration of N. binaloudensis by in vitro tissue culture. For this purpose, the experiments were set up to characterize the potential role of explants (the shoot tip, leaf, or stem), media (MS, ½ MS, and B5), and different concentrations of BAP alone or in combination with IAA for increasing N. binaloudensis propagation. Analysis of some morphological characteristics showed that stem-segment explant and macro-half strength (½ MS) medium were appropriate for inducing shoot formation. Enhancing shoot formation was correlated with an increased concentration of 1.5 mg L−1 BAP in combination with 1.5 mg L−1 IAA. An increase in IAA concentrations led to modulation of adventitious root formation, where the maximum rate of root formation was assayed under a combination of 1.5 mg L−1 IAA and 1.5 mg L−1 BAP. Results showed that about 30% of soil-cultivated plantlets survived when transferred to the field condition. This study describes a rapid protocol to conserve N. binaloudensis to meet future demand.