An Efficient In Vitro Regeneration System in Lentil (Lens culinaris) using Cotyledons with Half Embryonic Axes

Lentil (Lens culinaris Medik) crops are affected by a number of stresses such as drought, diseases (Fusarium wilt, Ascochyta blight) and pests (Etiella zinckenella and aphids). Lack of resistant sources within lentil gene pool prevents development of improved lentil varieties to resistant to these stresses. Gene technology could be an alternative approach for the development of elite genotypes resistant to the above stresses. However, one of the pre-requisites of genetic transformation methods is availability of an efficient and reliable in vitro regeneration and transformation protocol. We optimized an in vitro regeneration system in lentil using cotyledons with half embryonic axes as explants. For in vitro shoot regeneration, SIM medium (SIM6) supplemented with 1mg/L of 6-Benzyl amino purine (BAP) and kinetin (1mg/l) was found suitable. While shoot elongation was achieved on medium containing 0.5mg/L BAP (SEM3), the cotyledonary explants produced highest (8.3) number of multiple shoots per explant on SIM6 followed by SEM3 medium. The healthy shoots were rooted on MS basal medium after dipping the base of shoots in 1 mg/l IBA and rooted plantlets were established in soil. The protocol showed in vitro regeneration efficiency of 90.6%. Thus we developed an efficient in vitro regeneration protocol in lentil.