Indirect in vitro regeneration of lentil (Lens culinaris Medik.)

Establishment of an efficient and reproducible regeneration protocol is one of the basic prerequisites for genetic transformation of any crop plant. In vitro culture of lentil has proven to be difficult. In spite of a number of reports on the regeneration of this plant, very few satisfying and reproducible protocol has yet been reported. This study carried out for investigation of different hormone treatments and explants in order to establish a reproducible protocol for indirect in vitro regeneration of the cultivar Gachsaran  (commonly grown in Iran). For this purpose, the effects of 13 different hormone treatments and 4 explants on callus induction and regeneration were studied. Callus with the highest fresh and dry weight was produced on modified Murashige and Skoog (MS) medium containing 1 mg/L α-naphthaleneacetic acid (NAA)and 1 mg/L Zeatin (medium E). Among the explants, decapitated embryos attached to 1/4 of the cotyledon (DEAC) produced callus with the highest fresh and dry weights. In the regeneration stage, calli induced on media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) alone or in combination with other hormones did not result in shooting or rooting responses. The highest shooting and rooting responses (75%) were observed for callus induction medium E, using decapitated embryos with a quarter of the cotyledon as the explant.