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Á. PÉREZ CABO y C. GARCÍA MENDOZA AN. R. ACAD. NAC. FARM.

All these results suggest possible alternative strategies to
overcome the verticillium disease without the routinary use of
fungicides as could be, the production of A. bisporus and P. ostreatus
genetically lectin transformants, or the use of analogous molecules
to the V. fungicola glucogalactomannan ligand which can be
recognized by the carbohydrate-binding site(s) of each lectin.

This report may be the first establishing a close relationship
between the verticillium disease in A. bisporus and P. ostreatus fruit
bodies, demonstrating that the glucogalactomannan of V. fungicola
cell walls and a lectin from each mushroom behave as the «target
molecules» initiators of the subsequent molecular signaling which,
successively, will produce the respective «dry bubble» disease with
the necrosis of the fruit bodies. The present studies suggest that the
same glucogalactomannan-lectin interaction may occur in the V.
fungicola mycoparasitism described in the «hot mushroom» Agaricus
bitorquis also commercially grown (16) and, although up to now it
has not been described the presence of any lectin in these fruit
bodies, it presumably may exist.

Moreover, this article also suggests that other important
verticillium wilt diseases described in several crop plants (olive,
cotton etc.) could exhibit a rather similar mechanism of recognition
and binding between determined cell wall polysaccharides from
V. albo-atrum, V. dahliae, etc. (17) and their specific complementary
plant lectins, as the necessary step for the development of their
corresponding mycosis processes. Further studies are required to
prove whether this is a common phenomenon in the strategy of
Verticillium infections or if it occurred only in the cases previously
reported.

ACKNOWLEDGEMENTS

The authors acknowledge the Comisión Interministerial de Ciencia
y Tecnología (CICYT, AGL 2001-1885 and REN 2002-00660) and the
Junta de Comunidades de Castilla-La Mancha (188/CH-51) for
financial support, and the Centro de Investigación, Experimentación
y Servicios del Champiñón (CIES) for supplying the A. bisporus and
P. ostreatus fruit bodies.

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