Kailash Choudhary

The Mucuna pruriens Linn. is an important medicinal legume cover crop. Almost all the parts of the plant are reported to contain l-3,4-dihydroxy phenylalanine (l-DOPA), a non-protein amino acid that acts as precursor for the neurotransmitter dopamine. Here we report a rapid and reliable protocol for high fidelity regeneration of M. pruriens plants via somatic embryogenesis. Embryogenic callus was induced from cotyledon segments of in vitro grown seedlings on Murashige and Skoog medium supplemented with 6.7 μM 2,4-dichlorophenoxy-acetic acid (2,4-D). High-frequency somatic embryogenesis was achieved after transfer of embryogenic callus clumps to MS medium supplemented with 2.3 μM Kinetin (Kn) and 5.4 mM α-naphthaleneacetic acid (NAA) supplemented with 13.6 μM adenine sulphate. The maximum number of cotyledonary-stage embryos (60.5 ± 12.7) was obtained after 10 weeks. Mature somatic embryos were converted to plantlets on half strength MS basal medium with 90% survival rate in the field condition. The whole process required 12–16 weeks of culture for completion of all steps of plant regeneration. The protocol should provide an efficient means for large-scale cultivation and in vitro manipulation of M. pruriens, an important green manure cover-crop with medicinal properties.

An efficient in vitro regeneration protocol for moth bean [Vigna aconitifolia (Jacq.) Marechal] via somatic embryogenesis has been developed. Embryogenic callus cultures were established from the cotyledonary node as explant on semi-solid Murashige and Skoog (MS) medium supplemented with 0.75 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 6-benzylaminopurine (BA) and with various additives (50 mg l−1 ascorbic acid and 25 mg l−1 each of adenine sulphate, citric acid and l-arginine). Numerous somatic embryos differentiated on MS basal nutrient medium supplemented with 0.25 mg l−1 2,4-D and 0.5 mg l−1 of kinetin (Kin). Sustained cell division resulted in the formation of cell aggregates, which progressed to the globular- and heart-shaped somatic embryos and then, if they differentiated properly, to the torpedo shape and cotyledonary stages. The transfer of embryos onto fresh MS basal medium containing 0.2 mg l−1 BA and 2.0 mg l−1 gibberellic acid enabled the embryos to achieve complete maturation and germination. More than 80% of somatic embryos were converted into true-to-type fertile plants. In vitro-regenerated plantlets with well-developed roots were successfully hardened in a greenhouse and established in soil.