Cytochemistry of defense responses in cassava infected by Xanthomonas campestris pv. manihotis
Material type:![Article](/opac-tmpl/lib/famfamfam/AR.png)
- 61226
Item type | Current library | Collection | Call number | Copy number | Status | Date due | Barcode | Item holds | |
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CIAT Library Document collection CINFOS | Document Collection CINFOS | 61226 (Browse shelf(Opens below)) | c.1 | Short Loan | 100073657 |
Stems of susceptible and resistant cassava plants have ken cytologically investigated for their defense reactions to an aggressive strain of Xanthomonas campestris pv. Manihotis. Histochemistry, in conjunction with gold cytochemistry, revealed that in susceptible and resistant plants, phloem and xylem parenchyma cells displayed a wide ranged of responses that limited the bacterial growth within the infected plants. Lignification and suberization associated with callose deposition were effective mechanisms that reinforced host barriers in the phloem. In the infected xylem, vessels were plugged by a material of pectic and (or) lignin-like origin. Flavonoids have been seen to be incorporated in secondary cell wall coatings. These reactions occurred at a higher intensity in the resistant plants. The number of phloem and xylem cells producing autofluorescent compounds was higher in infected resistant plants than is susceptible plants. Reactions have been observed in the resistant variety only, such as secretion of phenol-like molecules by tyloses and hyperplasic activity of phloem cells that compartmentalized bacterial lysis pockets, which are potent secondary inoculum sources. eng