VARIATION AMONGST BRASSICA-JUNCEA CULTIVARS FOR REGENERATION FROM HYPOCOTYL EXPLANTS AND OPTIMIZATION OF CONDITIONS FOR AGROBACTERIUM-MEDIATED GENETIC-TRANSFORMATION
D. Pental et al., VARIATION AMONGST BRASSICA-JUNCEA CULTIVARS FOR REGENERATION FROM HYPOCOTYL EXPLANTS AND OPTIMIZATION OF CONDITIONS FOR AGROBACTERIUM-MEDIATED GENETIC-TRANSFORMATION, Plant cell reports, 12(7-8), 1993, pp. 462-467
Twelve cultivars of Brassica juncea grown in different agroclimatic re
gions of the world were tested for their ability to regenerate in vitr
o from hypocotyl explants and, accordingly, were divided into three gr
oups. One group of cultivars regenerated on MS medium supplemented wit
h 2,4-D, BAP and with NAA, BAP combinations; another group regenerated
only on MS with 2,4-D, BAP; and the third group showed very low regen
eration on both of these combinations. Inclusion of silver nitrate in
the medium was essential for high frequency of regeneration. In genera
l, Indian cultivars were more responsive than the cultivars of CIS and
Australian origin. Using the media optimal for regeneration and an Ag
robacterium-based binary vector carrying hpt and gus-intron genes, con
ditions for genetic transformation of B. juncea hypocotyl explants wer
e optimized. Transformation frequencies, identified by GUS staining at
the initial stages of growth, were lower on MS medium with 2,4-D, BAP
than on MS with NAA, BAP. Plants resistant to 20 mug/ml hygromycin we
re regenerated at a frequency of 11-36% from hypocotyl explants and we
re shown to be transformed by Southern blotting, GUS staining and prog
eny analysis.