INVESTIGADORES
GARRIZ andres
artículos
Título:
Polyamine metabolism during the germination of Sclerotinia sclerotiorum ascospores and its relation with host infection
Autor/es:
GARRIZ A, DALMASSO MC, MARINA M, RIVAS EI, RUIZ O.A. AND PIECKENSTAIN FL
Revista:
NEW PHYTOLOGIST
Editorial:
Blackwell
Referencias:
Lugar: Sheffield, Inglaterra; Año: 2004 vol. 161 p. 847 - 854
ISSN:
0028-646X
Resumen:
 Polyamine biosynthesis inhibitors were used to study polyamine metabolism during the germination of Sclerotinia sclerotiorum ascospores, and to evaluate the potential of polyamine biosynthesis inhibition for the control of ascospore-borne diseases in plants. ? The effects of inhibitors on ascospore germination, free polyamine levels, ornithine decarboxylase activity and development of disease symptoms on tobacco (Nicotiana tabacum) leaf discs inoculated with ascospores were determined. ? á-Difluoromethylornithine inhibited ornithine decarboxylase and decreased free spermidine levels, but had no effect on ascospore germination. Both, the spermidine synthase inhibitor cyclohexylamine and the S-adenosyl-methionine decarboxylase inhibitor methylglyoxal bis-[guanyl hydrazone] decreased free spermidine levels, but only the latter inhibited ascospore germination, at concentrations of 5 mm or higher. Lesion development on leaf discs was reduced by cyclohexylamine and methylglyoxal bis-[guanyl hydrazone], but not by á-difluoromethylornithine. In the absence of inhibitors, dormant ascospores contained higher polyamine levels than mycelium. ? Ascospore germination did not depend on ornithine decarboxylase activity and inhibitors of this enzyme will probably have a limited potential for the control of ascospore?borne plant diseases. On the contrary, spermidine synthase and S-adenosyl-methionine decarboxylase could be more suitable targets for fungicidal action. The relative insensitivity of ascospore germination to polyamine biosynthesis inhibitors may be caused by their high polyamine content.