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Which defensive chemicals help protect Asteraceae plants?
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Asteraceae
The flowering head of a sunflower (Helianthus annuus) is formed of yellow, petal-like ray flowers and a brown center of minute disk flowers.
The evolutionary success of the Asteraceae family is largely attributed to its diverse arsenal of secondary metabolites, which serve as chemical defenses against herbivores and other threats. These defensive compounds include:
- Sesquiterpene lactones: These are bitter compounds that provide significant protection.1
- Polyacetylenes: These chemicals often feature cyclic, aromatic, or heterocyclic end groups.1
- Terpenoid compounds: These are utilized in various ways, such as in volatile oils or released from the roots of certain species (like marigolds) to kill plant-parasitic nematodes in the soil.1
- Alkaloids: Specifically, pyrrolizidine alkaloids are notable in the tribe Senecioneae.1
- Latex: This substance acts as a physical and chemical barrier against attackers.1
These chemicals allow Asteraceae to thrive in a wide variety of habitats by deterring potential consumers and protecting the plants from damage.1