No abstract

A protocol for regeneration and micrografting of shoots of lentil (Lens culinaris Medik) was developed. Multiple shoots (4-5) were regenerated from cotyledonary node explants on Murashige and Skoog (MS) medium containing 8.8 mM 6-benzylaminopurine. In vitro regenerated shoots were micrografted on rootstocks with 96% efficiency. The successful grafts were transplanted to pots in Redi-earth TM , hardened off and were grown to maturity with 100% success. The success of the micrografting was independent of the nature and concentration of growth regulator used in shoot initiation medium and the time period for induction of shoots. The protocol was successful with several cultivars of lentil. The advantages of micrografting over in vitro rooting are discussed.

A rapid regeneration protocol for proembryos of Phaseolus angustissimus as young as 1 day after pollination (DAP) involving pod culture for 1 week followed by embryo culture for 2 weeks and embryo germination for 1 or 2 weeks is provided. Optimization of the media was conducted with pods collected 3 DAP. The best pod culture medium was composed of basal medium [(Phillips and Collins 1979) salts with (Geerts et al. 2001) vitamins], 1000 mg l )1 glutamine, 1000 mg l )1 casein hydrolysate, 3% sucrose and 0.5% agar. Embryo culture medium consisted of basal medium with 500 mg l )1 glutamine, 250 mg l )1 casein hydrolysate, 1.9 lM ABA, 3% sucrose and 0.5% bacto-agar. Embryos developed into plantlets on germination medium containing basal medium with 0.25 lM BA, 3% sucrose and 0.7% bacto-agar. Fertile, normal plants were recovered from direct embryogenesis and from micrografted embryo-derived shoots. Embryos obtained from pods collected 3 DAP regenerated plantlets at a rate of 29.3%, while embryos from pods collected 2 DAP and 1 DAP regenerated at rates of 20.2 and 4%, respectively. A second accession of P. angustissimus regenerated at a rate of 26.2%. Using this 5-week protocol for P. vulgaris resulted in a plantlet regeneration rate of 12.5%.