01914naa a2200205 a 450000100080000000500110000800800410001910000210006024501230008126000090020452012970021365000310151065000100154165300110155165300100156265300160157265300210158870000210160977300780163010501322024-01-16       1987    bl uuuu     u00u1 u    #d1 aCADENA-GOMEZ, G.  aPapila formation and associated peroxidase activityba non-specific response to attempted fungal penetration of maize.  c1987  aThe timing of papilla formation in the epidermis of the maize mesocotyl was followed after inoculation with Helminthosporium maydis and Colletotrichum graminicola. histochemical tests showed the presence of phenols and lignin in papillae and the surrounding cell wall material. Peroxidase enzyme activity was detected histochemically in the granules which appear prior to papilla formation and in the pappillae themselves. Soluble and ionically bound peroxidases were extracted from epidermal tissue during the time of papilla formation. The pattern of soluble anionic isozymes in epidermis which had been undergoing papilla formation was different from the pattern of isozymes from uninoculated epidermis or inoculated epidermis which had not yet started to form papillae. Eight isozymes were present in the soluble peroxidase fraction of uninoculated tissue and tissue inoculated but not yet forming papillae. Two new isozymes were detected in tissue in which papillae had been formed but in which fungal penetration had not yet occurred. The identical isozyme pattern was found in two maize cultivars during papilla formation in response to two different pathogenic fungi, suggesting that the occurrence of isozymes was part of a non-specific host response to attempted fungal penetration.  aColletotrichum Graminicola  aFungo  aFungus  aMaize  aPenetration  aReacao da planta1 aNICHOLSON, R. L.  tPhysiological and Molecular Plant Pathologygv. 31, n. 1, p. 51-67, 1987.