ISSN:
1570-7458
Keywords:
Leptosphaeria maculans
;
Peronospora parasitica
;
fungal pathogens
;
Phyllotreta cruciferae
;
flea beetles
;
Coleoptera
;
Chrysomelidae
;
Cruciferae
;
chitinase
;
myrosinase
;
allocation costs
;
plant defense mechanisms
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract We used artificial selection experiments to study genetic allocation costs and physiological mechanisms of resistance to herbivory and fungal disease. Genetic costs to resistance were present in some instances and absent in others. Genetic resistance to the fungal pathogen, Leptosphaeria maculans was cost-free, while resistance to Peronospora parasitica showed a negative genetic correlation between disease resistance and growth rate. Leptosphaeria resistant genotypes had 13% higher chitinase activity. Genetic increases in myrosinase activity were correlated with increased resistance to flea beetles (Phyllotreta cruciferae), but resulted in lower plant fecundity, presumably due to production costs of myrosinase. Genetic costs of resistance may maintain genetic variation in natural plant populations. These studies demonstrate the predictive and explanatory power of a functional approach to plant-herbivore and plant-pathogen interactions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00194764
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