American Journal of Plant Sciences, 2014, 5, 1-6
Published Online January 2014 (http://www.scirp.org/journal/ajps )
http://dx.doi.org/10.4236/ajps.2014.51001
Efficient Regeneration System for Genetic Transformation
of Mulberry (Morus indica L. Cultivar S-36) Using
in Vitro Derived Shoot Meristems
D. S. Vijaya Chitra
1*
, Bhaskarrao Chinthapalli
1
, G. Padmaja
2
1
Department of Biology, College of Natural Sciences, Arba Minch University, Arba Minch, Ethiopia;
2
Department of Plant Sciences,
School of Life Sciences, India University of Hyderabad, Hyderabad, India.
Email:
*
ds_chitra@fastmail.fm
Received November 13
th
, 2013; revised December 14
th
, 2013; accepted December 25
th
, 2013
Copyright © 2014 D. S. Vijaya Chitra et al. This is an open access article distributed under the Creative Commons Attribution Li-
cense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In
accordance of the Creative Commons Attribution License all Copyrights © 2014 are reserved for SCIRP and the owner of the intel-
lectual property D. S. Vijaya Chitra et al. All Copyright © 2014 are guarded by law and by SCIRP as a guardian.
ABSTRACT
Shoot meristems used for the study were exercised from the in vitro regenerated shoots cultured on MS medium
supplemented with 0.5 mg/L of BAP for multiplication. The sensitivity of the in vitro regenerated was studied
using shoot meristems of 0.5 cm. Shoot meristems were cultured on medium containing 10 - 100 mg/l kanamycin
to determine the concentration that was lethal for multiple shoot induction and root induction. The response of
shoot multiplication decreased (66.2% - 6.2%) as the concentration of kanamycin increased (10.0 - 70.0 mg/L)
with complete inhibition of shoot proliferation at 100 mg/L kanamycin. The rooting phase was very sensitive to
kanamycin compared to shoot multiplication. The percentage of shoots that rooted decreased (53.8% - 4.8%)
with increase in the concentration of kanamycin (10.0 - 70.0 mg/l) on IBA and 2,4-D supplemented medium. For
transformation studies, the shoot tips that were infected with Agrobacterium strain were placed on selection me-
dium containing MS medium with 0.5 mg/L BAP and 100 mg/L kanamycin and scored for the putative trans-
formed shoots. An average of 62.2% of shoot tips developed shoot buds from the base and the shoots reached a
length of 0.5 - 1.0 cm at the end of 30 days of culture on the selective medium in comparison to control which
showed no response. An average of 66.7% of the regenerated plants showed GUS expression on selection me-
dium where 43.2% and 65% of GUS expression was recorded in the leaves and callus. Leaves and callus induced
from the controls did not show GUS activity. Stable integration of nptII gene with the genomic DNA from these
transformed plants was confirmed through PCR analysis. Our result presents an efficient regeneration system
using in vitro derived shoot meristems for Agrobacterium mediated gene transfer.
KEYWORDS
Morus indica L. Cultivar S-36; In Vitro Regeneration; Shoot Meristems; Kanamycin; Genetic Transformation
1. Introduction
Mulberry (Morus spp.), a woody perennial tree plant
plays a significant role in sericulture, as its foliage con-
stitutes the main diet for silkworm (Bombyx mori L.).
The most important factor in the management of sericul-
ture is the improvement of mulberry cultivation for
achieving higher leaf yields. Mulberry leaves are essen-
tial for the survival of silkworms, since silkworms are
monophagus insects, which grow only by feeding on
mulberry leaves. Thus the cultivation of mulberry is the
most important factor in the production of silkworm eggs,
rearing of silkworm eggs, rearing of silkworm cocoons
and on the whole in the entire operation of sericulture.
Mulberry cultivation is fraught with many problems in
the form of biotic and abiotic stresses. Among the vari-
ous biotic stresses, fungal diseases cause a major damage
to this crop [1]. Mulberry is improved qualitatively and
quantitatively by conventional genetic approaches. How-
*
Corresponding author.
OPEN ACCESS AJPS