Manchanda et al.

number of studies have been conducted in sugarcane

associated with poor regeneration and recalcitrant

dealing with shoot tip culture (Fitch and Moore

behaviour of culture materialfurther affecting callus

1993), callus induction (Rani et al. 2012) and direct

growth, shoot generation, rooting and somatic

plant regeneration (Mittal et al. 2013).

embryogenesis (Pua and Chi 1993). Most of the plant

An efficient tissue culture system for the regeneration

tissues have the tendency to produce ethylene. The

of plants from explants depends upon several

effect of ethylene on in vitro morphogenesis, as with

aspects, of which shoot regeneration and rooting are

other phytohormones, depends on its concentration

the most important aspects (Purnhauser et al. 1987).

in and around the cultured tissues, as well as their

In plant tissue culture and genetic transformation

sensitivity to it (Thorpe 1994). Silver nitrate is usually

experiments, closed vessels are used for the purpose

employed in in vitro studies for inhibiting ethylene

of avoiding contamination. As a result, ethylene

action because of its water solubility and lack of

phytotoxicity at effective concentrations (Beyer

(C ₂ H ), a ubiquitous hormone, is produced which is

4

1976).

Figure 1 Establishment of shoot organogenesis and regeneration in sugarcane cv.CoJ 83

(A) Leaf roll segment placed onMS+ NAA (5 mgl-1) + Kin (0.5 mgl-1) +3.0% sucrose + 0.8% agar medium (B) Direct shoot

regeneration from leaf roll segment after 14-15 days of culturing (C) Shoot elongation from leaf roll segment

(D) Comparison of number of shoots formed on medium supplemented with 3 mgl-1 AgNO3 and control

(E) Rooting of plantlets on liquid MS medium + NAA(3.0 mgl-1) + IBA (2.0 mgl-1) + sucrose (7%) medium

(F) Hardening of rooted plantlet on pre-soaked cotton for 4 days under high light intensity (5000 lux)

(G) Plantlets transferred to polybags containing soil and farmyard manure in 1:1 ratio

760