Salicylic Acid and Chitinase in Infected Cucumber Plants

Local and Systemic Biosynthesis of Salicylic Acid in Infected Cucumber Plants

“…It ís known that cucumber plants accumulate SA systemically (Métraux et al, 1990;Rasmussen et al, 1991;Meuwly et al, 1994;Mdlders et al, 1994) and display SAR in leaf 2 of a plant infected on leaf 1 (Métraux et al, 1990;P. Meuwly, M. Crausaz, A. Buchala, and J.-P. Métraux, unpublished data).…”

“…In tobacco, free and bound SA are produced around the infection site, whereas only free SA is detected in dista1 regions (Yalpani et al, 1991;Enyedi et al, 1992;. In cucumber Meuwly et al, 1994;Molders et al, 1994) ' This work was partially supported by grant No. 31-37098.92 * Corresponding author; e-mail jean-pierre.metraux@unifr.ch; from the Swiss National Science Foundation.…”

Salicylic acid accumulates in the roots and hypocotyl after inoculation of cucumber leaves with Colletotrichum lagenarium

“…The accumulation of SA in the upper leaves was between 400 and 3000 ng/g, which was greater than that induced by the Tobacco necrotic virus, and similar or greater than that induced by P. lachrymans in cucumber plants (Meuwly and Métraux, 1993;Meuwly et al, 1994;Mölders et al, 1994Mölders et al, , 1996. The magnitude of the increase in SA differed according to the species of pathogen and the inoculation method used.…”

“…Our present results confirm the accumulation of SA in the root and hypocotyl below the inoculated leaves, although the increase in the lower leaf was not significant. SA accumulation in cucumber roots after inoculation with Pseudomonas lachrymans into the cotyledons was mentioned by Meuwly et al (1994), but was not described in detail. The increase in concentration of SA in the root occurred subsequently to the increase in the upper leaves and stem.…”

“…The increase in concentration of SA in the upper leaves also occurred later than in the stem parts (Métraux et al, 1990), possibly suggesting a time lag in the translocation of the signal. The transport of signals to the lower, lateral and opposite sides of plants to induce SAR and SA accumulation has suggested the involvement of pathways other than the vascular bundles (Chen et al, 1999;Gessler and Kuć, 1982;Guedes et al, 1980;Jenns and Kuć, 1977;Kiefer and Slusarenko, 2003;Abiko, 2000, 2001;Madi and Katan, 1998;Meuwly et al, 1994;Reglinski et al, 2001;Tjamos, 1979;Xue et al, 1998). The signal is presumed to use both the phloem and alternative pathways.…”