Physiology and costs of resistance to herbivory and disease in Brassica
1996
Mitchell-Olds, T. | Siemens, D. | Pedersen, D.
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 plantpathogen interactions.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library