Canadian Journal of Botany - Revue Canadienne de Botanique (1992) 70, 1824-1833

Hamed K. Abbas, Rex N. Paul, C. Douglas Boyette, Stephen O. Duke and Ronald F. Vesonder (1992)
Physiological and ultrastructural effects of fumonisin on jimsonweed leaves
Canadian Journal of Botany - Revue Canadienne de Botanique 70 (9), 1824-1833
Abstract: The physiological and ultrastructural effects of fumonisin B₁, a phytotoxin obtained from Fusarium moniliforme, on jimsonweed (Datura stramonium L.) were studied. When fumonisin B₁ was applied at concentrations of 3 to 1000 μg/mL (4.1 to 1388 μM) to jimsonweed leaves, effects such as electrolyte leakage, autolysis, and photobleaching of tissues were noted in less than 12 h after exposure to light (480 μmol per m^-2 per s^-1, PAR) at 25 °C. The degree of damage was directly proportional to the concentration and duration of exposure in all cases. Chlorophyll reduction from 5 to 73% occurred after 48 h in the light. In darkness, electrolyte leakage above control levels was noted only in treated samples after 72 h. However, when these dark-treated samples were subsequently placed in the light, electrolyte leakage occurred in 12 h. Ultrastructural damage in mesophyll palisade cells exposed to 500 μg/mL fumonisin B₁ began at 6 h and intensified after 12 h. Cytoplasmic degeneration occurred first, followed by disruption of the chloroplasts and accumulation of intracellular debris. The close structural analogue, AAL-toxin, has previously been reported to act by inhibiting nucleotide synthesis. The phytotoxic activity of both AAL-toxin and fumonisin was not influenced by supplying supplemental aspartic or orotic acid, indicating that neither toxin acts by inhibiting nucleotide synthesis. These results indicated that fumonisin B₁ caused rapid, light-dependent cytoplasmic and chloroplast disruption, through an unknown mechanism.
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Link to article at publishers website
Database assignments for author(s): Stephen O. Duke, Hamed K. Abbas

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
damage/losses/economics

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Fusarium verticillioides