Bk. Dennehey et al., COMPARISON OF SELECTIVE AGENTS FOR USE WITH THE SELECTABLE MARKER GENE BAR IN MAIZE TRANSFORMATION, Plant cell, tissue and organ culture, 36(1), 1994, pp. 1-7
The effectiveness of four phosphinothricin (PPT)-based selective agent
s were evaluated for use in maize transformation: glufosinate, bialaph
os, Basta(R) and Herbiace(R). Glufosinate and its commercial formulati
on, Basta(R), were less effective in controlling growth of non-transge
nic corn callus than the tripeptide, bialaphos, or its commercial form
ulation, Herbiace(R). Addition of 25 mM L-proline had no significant e
ffect on selection when using bialaphos. However, when L-proline was i
ncluded with the selective agent glufosinate, selection was inhibited
and callus growth was enhanced. At four weeks, callus growth on 0.3, 1
.0 and 3.0 mg l-1 glufosinate in the presence of proline was 76, 43, a
nd 21% of control growth, respectively, and in the absence of proline
was only 32, 9, and 6% of control growth. Optimized selection protocol
s for Basta(R) and bialaphos yielded comparable numbers of transforman
ts. Using these protocols, fertile transgenic plants were regenerated
from transformed callus cultures.