Regeneration of pigeonpea (Cajanus cajan) from cotyledonary node via multiple shoot formation

Abstract

Plant regeneration, which is the major limiting factor for transformation of Cajanus cajan, has been obtained via multiple shoot formation from the cotyledonary node region of seedlings germinated on MS medium containing 2 mgl(-1) 6-benzylaminopurine. A mass of multiple shoot-initials formed at the axillary bud region of the cotyledonary node of the seedlings within two weeks. The cotyledonary node along with the mass of shoot-initials excised from the seedling, continued to form new shoot-initials on MS medium containing 6-benzylaminopurine (2 mgl(-1)) and supplemented topically with indole-3-acetic acid. The formation of new shoot-initials was also observed from the cotyledonary nodal explant, after cutting off its surface layers to completely remove the pre-existing shoot-initials and culturing it on 6-benzylaminopurine (2 mgl(-1)) containing medium. The shoots elongated rapidly on basal MS medium and rooted efficiently in MS medium supplemented with indole-3-butyric acid (0.5 mgl(-1)). The procedure described is efficient, and highly reproducible and a common response was observed for all the six varieties tested.

In vitro regeneration through organogenesis and somatic embryogenesis in pigeon pea [Cajanus cajan (L.) Millsp.] cv. JKR105

“…On the other hand, the explants cultured on <0.5 mg L −1 and >0.5 mg L −1 BAP showed significantly low shoot bud elongation. Furthermore, alteration in media composition (Malik and Saxena 1992b;Shiva Prakash et al 1994), substitution of plant growth regulators (Mohamed et al 1991;Nagi et al 1997), and changes in light conditions had a significant effect on shoot elongation. Franklin et al (2000) observed that the incubation of embryonal axes of pigeon pea, under light-dark conditions, though favored the shoot bud formation, was less efficient for elongation.…”

“…Mehta and Mohan Ram (1980) reported that higher concentration of BAP induced direct shoot regeneration from the cotyledonary surface. While low concentrations of BAP favored the development of shoot buds from the pre-existing meristems (Shiva Prakash et al 1994;Ignacimuthu et al 1997). However, higher number of viable plants were regenerated on KIN medium in several cereal crops (Bhaskaran and Smith 1990).…”

“…In pigeon pea, the regeneration of plants by organogenesis has been reported via pre-existing meristems like apical meristem (Cheema and Bawa 1991), undifferentiated callus (Kumar et al 1983;George and Eapen 1994), differentiated non-meristematic leaf tissue Eapen et al 1998;Geetha et al 1998;Singh et al 2002;Dayal et al 2003;Villiers et al 2008); and seedling tissues such as hypocotyl (Cheema and Bawa 1991;Geetha et al 1998), cotyledon (George and Eapen 1994;Geetha et al 1998;Mohan and Krishnamurthy 1998;Chandra et al 2003), cotyledonary node (Mehta and Mohan Ram 1980;Kumar et al 1983Kumar et al , 1984Naidu et al 1995;Shiva Prakash et al 1994;Geetha et al 1998;Singh et al 2003), epicotyl (Kumar et al 1984;Naidu et al 1995;Geetha et al 1998), and embryonal axes (Sarangi and Gleba 1991;George and Eapen 1994;Naidu et al 1995;Franklin et al 2000).…”

In vitro plant regeneration of Albizia lebbeck (L.) from seed explants

“…The application of intact seedling method in the propagation of multipurpose plant species provides timely supply of plant materials required for the isolation of drugs by the pharmaceutical industries without depleting natural plant resources as well as for reforestation of degraded and exploited lands. Several authors (Malik et al, 1993;Prakash et al, 1994;Bhuyan et al, 1997;Arya et al, 1999;Das et al, 1999;Hussain et al, 2008) have reported the use of intact seedling method in several medicinally and economically important plant species (Lathyrus cicera, Cajanus cajan, Murraya koenigii, Dendrocalamus asper, Litchi chinensis and Sterculia urens) for quick germplasm production and conservation.…”

In vitro multiple shoot bud induction and regeneration from plumule junction explants of pigeon pea [Cajanus cajan (L.) Mill sp.] cultivars

“…In vitro regeneration by organogenesis using diverse explants like leaf discs (Kumar et al, 1983;Eapen and George, 1993;George and Eapen, 1994;Eapen et al, 1998;Geetha et al, 1998;Dayal et al, 2003), cotyledons (Kumar et al, 1983;Mehta and Mohan, 1980;Kumar et al, 1984;Sarangi and Gleba, 1991;Naidu et al, 1995;Srinivasan et al, 2004;Chandra et al, 2003), cotyledonary nodes (Geetha et al, 1998;Shiva et al, 1994) and embryonal axes (George and Eapen, 1994;Sarangi and Gleba, 1991;Naidu et al, 1995;Franklin et al, 2000;Mohan and Krishnamurthy, 1998) has been reported. More than 50 diverse genotypes have been attempted for regeneration via organogenesis to develop suitable regeneration protocol amenable to transformation with desired genes (Krishna et al, 2010).…”