Micro-propagation of air yam (Dioscorea bulbifera L.)
Loading...
Date
2005
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
The present investigation was carried out to optimize conditions
and develop an improved protocol for micropropagation in air yam
(Dioscorea bulbifera L.). Nodal and shoot tip explants were used for
shoot regeneration on different media supplemented with both
synthetic phytohormones as well as cell free extract of phytohormones
producing bacteria (Acetobacter diazotrophicus 767-50 and Azotobacter
chroococcum-103). Response for shoot regeneration was observed
within a week on all the media tested for nodal explants and from
shoot tip explants shoot regeneration was observed only on medium
supplemented with 15 mg/l adenine sulphate and 2 mg/l kinetin.
Nodal explants gave best shoot regeneration (100%) on MS medium
supplemented with adenine sulphate (15 mg/l) and kinetin (2 mg/l).
On the same medium after subculturing of nodal explants, when
shoot induction started maximum (15-20) multiple shoots were
observed in 76.66 per cent of the shoots while in the remaining
shoots, 3-4 shoots per explant were observed Maximum (97.77%)
rooting of shoots was observed on MS medium supplemented with 0.5
mg/l IAA. Healthy and strong rooting was observed on all the media
tested within 15 days of culturing. Survival rate of regenerated
plantlets was observed to be more than 90 per cent on transplantation
to soil.
The earliest shoot regeneration response was observed on 7th
day on all the media supplemented with cell free extract of A.
diazotrophicus, A. chroococcum and combination of both. Maximum
82.22 per cent and 88.88 per cent shoot regeneration response was
observed on MS media supplemented with 15 mg/l adenine sulphate
+ 1.5 ml/l cell free extract of A. diazotrophicus and 15 mg/l. Adenine
sulphate + 1.5 ml/l cell free extract of A. chroococcum, respectively
from nodal explants. Shoot regeneration response was observed
maximum (88.88%) on MS medium supplemented with 15 mg/l
adenine sulphate + 0.5 ml/l cell free extract of A. diazotrophicus + 0.5
ml/l cell free extract of A. chroococcum. Root formation alongwith
shoots was also observed on all the media supplemented with cell free
extracts of both the bacterial strains. The number of shoots per
explant regenerated on MS medium supplemented with cell free
extracts of A. diazotophicus as well as A. chroococcum was found to be
2-3, whereas 3-4 shoots per explants were observed on the media
supplemented with combination of cell free extracts of A.
diazotrophicus and A. chroococcum.