Ultrastructure and histochemistry of the resistant tissue surrounding lesions of tomato bushy stunt virus in Gomphrena globosa leaves

Unusual Phenolic Compounds in the Hypersensitive Reaction of Gomphrena globosa to Tomato Bushy Stunt Virus

“…The hypersensitive reaction is a complex phenomenon during whidi at least two distinct events have been recognized (JOCKUSCH 1966, MARTIN and GALLET 1966, PENNAZIO et al 1976, SHIMOMURA 1971, TAKAHASHI 1975: virus localization and necrogenesis. In this connection, the appearance of newly synthesized compounds may be interpreted in different ways: (1) they are a consequence or by-products of the necrotic process; (2) they represent markers of necrogenesis, i.e.…”

“…(1) its appearance is delayed and quantitatively reduced when systemic instead of local infection takes place {compare Table 2 with Tables 4 and 6); (2) it is present in tissues surrounding local lesions, were a localized acquired resistance has been demonstrated ; (3) it is present in tissues showing the highest level of hypersensitivity, such as mature leaves (PENNAZIO et al 1976).…”

“…Gomphrena globosa L. plants normally react with local lesions to tomato bushy stunt virus (TBSV) infection (PENNAZIO et al 1976). The morphological changes occurring in the local lesions and In the surrounding tissues suggest that morphological barriers do not play a primary role in virus localization.…”

“…We report here the presence of unusual compounds during the hypersensitive reaction of G. globosa to TBSV, whidi do not appear to be incidental by-products of necrogenesis. previously described (PENNAZIO et al 1976).…”

“…With reference to the plastodiron index (PI) and leaf plastodiron index (LPI) as previously defined for G.globosa (PENNAZIO et al 1976), all the experiments were performed on PI 5 plants (i.e. those having four pairs of fully developed leaves) and viruses were inoculated on LPI 1 leaves (the fourth pair).…”