Somatic Embryogenesis and Plant Regeneration from Juice Vesicles of Mexican Lime (Citrus aurantifolia L.)

Callus production, somatic embryogenesis and plant regeneration were achieved from juice vesicles of Mexican lime. First, three types of culture media, Murashige and Skoog (MS), Murashige and Tucker (MT) and Grosser and Gmitter (H+H) and different levels of 2,4-Dicholorophenoxy acetic acid (2,4-D) were used to study their effects on production and proliferation of embryogenic calli from juice vesicles. Second, for initiation of somatic embryos from embryogenic calli, five different media and twenty combinations of growth regulator treatments were investigated. Results showed that MS medium supplemented with 0.5 mg/l 2,4-D produced maximum embryogenic calli. In MT and H+H media, maximum calli were obtained with 0.5 and 1.5 mg/l 2,4-D, respectively. Somatic embryos were formed only by the use of MT medium containing 500 to 700 mg/l malt extract. Embryos germinated and completed their growth on MS medium supplemented with 1.0 mg/l Gibberlic acid (GA3) and 0.02 mg/l α-Naphthalene acetic acid (NAA). Maximum shoot length and leaf number were observed when 1.0 mg/l GA3 was added to the MS medium. Plantlets were transferred into pots containing of 1:2:2 volume ratio of soil mixture (sand, peat moss and perlite, respectively) and the rate of survival was 100%.