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FREEDOM PALESTINE FREEDOM PALESTINE FREEDOM PALESTINE
Chemical Control 187
Fungus species and
taxonomic group
Aspergillus niger v. Tiegh.
A. flavus Link
A. ochraceus Wilhelm
Geotrichum candidum Link
Botrytis cinerea Pers.
Fusarium moniliforme Sheld.
Trichoderma viride Pers. ex Fries
Diplodia natalensis P.E.
Stemphylium botryosum Wall.
Alternaria tenuis Nees
Cladosporium herbarum (Pres.)
Link
Chemical
category^
Chitin-P-glucan
WGA
+
+
+
+
+
+
+
+
+
+
+
Lectin^
SBA PNA ConA
±
±
+
H-
±
±
-
-
-
-
—
± +
± +
+ +
- +
- +
- +
- +
- ±
-
-
— —
The binding of PNA and SBA occurred typically along the hyphal
walls, with no pronounced binding at the tips and septa, indicating that
both lectins bind preferentially to relatively mature regions of the
hyphae. The binding pattern of WGA, on the other hand, emphasized
that this lectin binds to regions of the hyphae in which chitin is actively
synthesized (Barkai-Golan et al., 1978).
The three lectins were also found to inhibit the incorporation of
acetate, N-acetyl-glucoseamine and galactose into young hyphae of
Aspergillus ocharaceus, indicating the interference with normal fungal
activity and growth (Barkai-Golan et al., 1978).
These results suggest that lectins may be useful in studies of chemical
composition of hyphal wall surfaces. Lectins with different sugar
specificities have actually been efficient in studying hyphal cell walls of
mycobionts isolated from different lichens (Galun et al., 1976) and were a
useful aid for the study of cell wall composition of yeasts of different
taxonomic groups (Barkai-Golan and Sharon, 1978). However, the
findings also support the suggestion that one role of lectins in plants is
protection against fungal pathogens.
Additional support for the antifungal capacity of lectins was
contributed by an extensive study with 11 purified lectins, representing
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