Influence of taxonomic relatedness and medium composition on meristematic nodule and adventitious shoot formation in nine pine species

Abstract

Embryos of Pinusechinata Mill., Pinustaeda L., Pinusserotina Michx., Pinuseldarica Medwed., Pinuscaribaea Morelet, Pinusoocarpa Scheide, Pinustecunumanii (Schwd.) Equiluz & Perry, Pinusstrobus L., and Pinusradiata D. Don were cultured following the protocol for Pinusradiata to determine if a perpetual meristem culture could be produced. Two subsequent experiments were done that included modifications to the medium's mineral composition, strength (modified LePoivre and Murashige and Skoog at half-strength and full strength), cytokinin concentration (1.0, 2.5, and 5.0 mg/L benzyladenine), and auxin concentration (0 and 0.1 mg/L indolebutyric acid). Pines in subsection Australes performed poorly in culture relative to those species in subsection Oocarpae. Pinusradiata and Pinuseldarica were the only species to produce long-term subculturable meristematic tissue, although shoots were obtained with seven of the species. Half-strength modified LePoivre medium containing 2.5 mg/L benzyladenine but no auxin gave the best results with most species. Significant differences in shoot production were found among Pinusoocarpa provenances.