Rapid in vitro plant regeneration of black gram (Vigna mungo L. Hepper) Var. Sarala, an important legume crop

Abstract

Efficient in vitro regeneration of black gram (Vigna mungo L. Hepper) var. Sarala was achieved through organogenesis using cotyledonary explants excised from 4 days old seedlings on MS medium supplemented with 2.0 mg/l BAP. Organogenic calli were developed from cotyledonary tissues within 4-6 weeks of culture on MS medium supplemented with 3.0 mg/l 6-benzylaminopurine (BAP) along with 2.0 mg/l 1-napthaleneacetic acid (NAA). Shoot bud regeneration was achieved on MS medium supplemented with 2.0 mg/l BAP within 3-4 weeks of subculture. The number of shoots per culture varied from 1.12 to 8.75 in different growth media. The cultures incubated initially on dark photoperiod for 2 weeks and subsequently transferred to 16 h photoperiod showed higher number of shoot bud regeneration. The proliferated shoots were further sub-cultured on similar medium for higher rate of shoot bud regeneration. The elongated shoots were rooted on 1/2 strength MS medium fortified with 0.1-0.5 mg/l NAA or indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) with 2 % (w/v) sucrose within 2-3 weeks of culture. The higher percentage of rooting was obtained on 0.1-0.25 mg/l NAA as compared with IBA or IAA. The rooted plantlets were transferred to soil mixture (soil: sand: vermi-compost, 1:1:1 ratio) and kept in the greenhouse with 85 % humidity. The regenerated plantlets were successfully grown with 75 % survival rate. This protocol can be used for genetic improvement of black gram. © 2013 The Author(s).