Abstract:
Much attention has been focused on examining the sequence of different changes that are triggered upon invasion of a pathogenic organism to a higher plant. Of the most rapid changes are those related to the morphological appearance of the infected plant. In the present work, growth of L.termis in Fusarium-pathogenized soil points to marked increase in root and shoot length, decrease in fresh and dry weights of roots and obvious increase and decrease in fresh and dry weights of shoots, respectively. Such changes were associated with marked decreases in soluble sugars, starch, and Ca and Mn contents of the roots. The present results revealed also a prominent increase in soluble proteins and P content of roots at the 1st 2nd states of growth. With the exception of an elevated level of soluble sugars and Mn, the shoot system of L termis suffered from marked decrease in starch, soluble proteins, P, Ca contents as a result of Fusarium pathogenesis. The chlorophyll content of leaves subjected to obvious decrease (chl. a) and marked increase (chl. b) in response to Fusarium investment. Growth promotion induced by Streptomyces chibaensis was underlain with obvious increases in shoot length, fresh and dry weights of roots and shoots lf L. termis. Enhanced growth of shoots was synchronized with marked increase in soluble sugars, starch, soluble proteins and the chlorophyll a and b contents. Moreover, there was an obvious increase in the shoot content of Ca, P and Mn. On the other hand, a marked decrease in root length and its content of soluble sugars and Ca was observed and was associated with increase in the content of starch, soluble proteins, P and Mn. In response to F. oxysporum the yielded seeds were characterized by a relatively low content of starch, soluble proteins, total nitrogen, P, Ca, Fe, Zn and Mn, associated with high level of soluble sugars and obvious decrease in the activity level of peroxidase and catalase. S. chibaensis when applied alone or in combination with F. oxysporum, on the other hand, induced marked increase in the seed content of all the above mentioned parameters. Moreover, S. chibaensis had provided the seeds with unique proteins which playing crucial role against pathogenic invasion, providing the seeds with rapid reactivity against pathogens. Moreover, some of these proteins have antimicrobial activity and others initiate the lysis of fungal cell walls.
Page(s):
463-472
DOI:
DOI not available
Published:
Journal: International Journal of Agriculture and Biology, Volume: 5, Issue: 4, Year: 2003