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Barley chitinase (35
kDa)
reponed in this study showed a broad-spectrum in
vitro antifungal activity against six fungi
B.
cinerea (blight of tobacco).
P.
rheae (leaf
spot of tea). B. oryzue (brown spot of rice), Alrcrnnrio sp. (grain discoloration in
rice),
C.
lunata (leaf spot of clover), and R. s o l u ~ ~ i (sheath blight of rice) even at a
concentration of 100 pg. Barley chitinase induced lysis 2nd fragmentation of the
mycelium. Wall disruption, release of chitin oligosaccharides frorn cell walls
and
cytoplasmic leakage due to chitinase were also observed in ultrastructural studies.
Thus. the reported Bar2chi exhibited potent antifungal properties.
Antimicrobial potential of LTPs against phytopalhogens has been reponed
(Terras et al., 1992; Molina er al., 1993; Segura
ef
al., 1993) although not are all the
LTPs are antimicrobial. LTPs have been established as the members of PR-protein
family (Van Loon and Van Strien, 1999). Some members of the nonspecific-lipid
transfer proteins (ns-LTP) that facilitate in vitro transport of lipids also showed
antimicrobial activity in vitro. Nielsen et al., (1996) reported two novel nearly
identical antifungal proteins (IWFI and IWF2) from sugar beet leaves. Velazhahan el
91.. (2001) reported an antifungal protein from pearl millet seeds with extensive N-
terminal sequence similarity to lipid transfer proteins of cotton, wheat and barley. An
antifungal LTP protein from sunflower seeds showed inhibition of spore germination
against F. soluni f. sp. eumurtii. Wang et al., (2004) reported ns-LTP from mung bean
with antifungal and antibacterial activities against
F.
solani,
F.
oxysporum, Pyrhium
aphanidermatum, Sclerorium rolfsii and Sraphylococcus aureus. As reported earlier.
transgenic rice containing the homologous ns-LTP gene (Ace-AMPI) of Allium cepa
showed antimicrobial activity towards
M.
grisea,
R.
solani and
X.
oryzue pv. oryzae
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