Effect of explant type and culture medium on in vitro establishment and growth of Solenostemon rotundifolius

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Résumé

In Burkina Faso, Solenostemon rotundifolius [(Poir.) J.K. Morton] is an underutilized tuber crop of considerable economic and medicinal importance. However, the conservation of stored planting material is constrained by microbial contamination, which can adversely affect subsequent plant development in the field. This study aimed to identify the most suitable explant type for the in vitro regeneration of the species. The experiment was conducted under laboratory conditions using a completely randomized 3 × 4 factorial arrangement with 15 replicates per treatment combination. The first factor was explant type (buds, simple cuttings, and uninodal cuttings), and the second factor was culture medium at four levels: M0 (Murashige and Skoog (MS) basal medium without plant growth regulators); M1 (MS medium supplemented with 5.0 mg/L 6-benzyladenine (BA) and 0.1 mg/L naphthaleneacetic acid (NAA)); M2 (MS medium supplemented with 1.0 mg/L BA); and M3 (MS medium supplemented with 0.5 mg/L indole-3-butyric acid (IBA)). Explant recovery rate, plantlet height, root length, and numbers of leaves, nodes, stems, and roots were evaluated. Significant differences among explant types were observed for the measured growth parameters. The highest treatment-specific recovery rates were recorded for simple cuttings on M0 (93.33 ± 5.25%) and buds on M2 (60.00 ± 13.09%). M0 favoured rooting and establishment, whereas M2 promoted shoot development and proliferation. S. rotundifolius plantlets derived from simple cuttings showed the strongest overall vegetative performance. These findings highlight the importance of explant physiological status and growth-regulator balance in improving regeneration efficiency in this species.

Mots-clés

explant regeneration; in vitro culture; neglected and underutilised crops; rhizogenesis; shoot proliferation; Solenostemon rotundifolius; tissue culture