Jp. Wubben et al., ACCUMULATION OF PATHOGENESIS-RELATED PROTEINS IN THE EPIDERMIS OF TOMATO LEAVES INFECTED BY CLADOSPORIUM-FULVUM, Netherlands journal of plant pathology, 99, 1993, pp. 231-239
Upon infection by Cladosporium fulvum, tomato plants start to produce
pathogenesis-related (PR) proteins. The PR proteins 1,3-beta-glucanase
, chitinase, and PR-lb accumulated near the stomata in the lower epide
rmis of C fulvum-inoculated tomato leaves as could be determined by im
munolocalization with polyclonal antibodies. However, no differences i
n accumulation of PR proteins between a compatible and an incompatible
interaction were found. Results obtained from enzyme activity measure
ments of 1,3-beta-glucanase and chitinase on similar leaf material as
used for the immunolocalization did not fully reflect the immunolocali
zation data. The antibodies possibly detect only the extracellular but
not the intracellular enzymes. The accumulation of PR proteins near t
he stomata might be part of a general defence response of plants again
st pathogens and potential pathogens.