ABSTRACT
A cephalosporin antibiotic, cefotaxime (Omnatax™) promoted somatic embryogenesis and subsequent shoot regeneration in vitro from spindle in sugarcane irrespective of the genotypes as (CoJ 83, CoJ 88 and CoJ 64) culturered on MS medium with 2,4-D (2.5 mgl(-1)) and kinetin (0.5 mgl(-1)). Seven different concentrations of cefotaxime (100, 200, 300, 400, 500, 600 and 700 mgl(-1)) were tested to find the optimal concentration of cefotaxime for somatic embryogenesis from callus cultures. Among the three varieties, calli of variety CoJ 83 incubated on MS medium with 2,4-D (2.5 mgl(-1)) + kinetin (0.5 mgl(-1)) + cefotaxime (500 mgl(-1)) exhibited maximum somatic embryogenesis. To improve shoot regeneration, the callus was transferred to MS medium with BAP (0.5 mgl(-1)) + kinetin (0.5 mgl(-1)) in combination with different levels of cefotaxime. Highest frequency of shoot regeneration was observed in callus of CoJ 83 in the presence of 500 mgl(-1) cefotaxime. The plantlets could be successfully hardened in polybags and transferred to soil, where they exhibited normal growth. Our results convincingly demonstrated that cefotaxime improves somatic embryogenesis from spindle and regeneration from embryogenic calli of sugarcane and hence can be strongly recommended for rapid and large scale multiplication of sugarcane.
ABSTRACT
An antibiotic, cefotaxime (Omnatax) has been found to promote somatic embryogenesis and subsequent plant regeneration in vitro in indica-type basmati rice cultures. Response was highly genotype specific. The number, mass and morphology of the calli formed on the scutellar tissues were dependent on the growth medium (with or without cefotaxime). The embryogenic nature of nodular calli was confirmed through histological analysis and their plant regeneration ability. The calli of variety Pusa basmati 1 grown on medium supplemented with cefotaxime (100 mg/L) exhibited up to 70.5% plant regeneration as compared to control (51.51%). Plants regenerated from emryogenic calli were phenotypically normal and identical to seed-derived plants and exhibited normal fertility. A limited humidity and an optimal aeration of the culture tubes further enhanced the frequency of somatic embryogenesis and plant regeneration.
