Abstract |
Baculoviruses have a significant potential as biological pesticides.
Spodoptera littoralis multicapsid nucleopolyhedrovirus (SpliMNPV) could
thus find an application to protect plants against the African Cotton
Leafworm. For the in vitro production of SpliMNPV a cellular system has to
be established. For this purpose three new continuous cell lines were
established from the embryonic tissue of the cotton leaf worm S.
littoralis.The three cell lines were designated Spli-C, Spli-S and Spli-B.
They consisted mostly of spherical cells, but also contained spindle and
giant cells. The population doubling time for the three cell lines Spli-C,
Spli-S and Spli-B were 30.5, 31 and 44.5 hrs, respectively, at passage 19,
while at passage 120 it decreased to 26, 27 and 32 hrs, respectively. RAPD
and DAF DNA fingerprint confirmed that the cell lines originated from S.
littoralis tissues. The lactate dehydrogenase (LDH) isozyme analysis
demonstrated a distinguishable difference between the three new S.
littoralis cell lines and the other insect cell lines which we use in our
laboratory. All three new cell lines were susceptible to SpliMNPV and thus
are suitable for virus multipication. Cells were immobilized using sodium
cellulose sulfate (NaCS) and poly diallyl dimethyl ammoniumchloride
(PDADMAC) capsules to protect cells from shear stress. This is caused
during cultivation by agitation and gas sparging during supply of
sufficient oxygen in order to reach high cell densities. The cell
densities increased from 4-5x10^6 cells/ml in suspension culture to
1.3x10^7 cells/ml in capsules. Our results suggest that large-scale
production of SpliMNPV as a biopesticide is possible with these cell lines.
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