Whiteflies glycosylate salicylic acid and secrete the conjugate via their honeydew.

During insect feeding, a complex interaction takes place at the feeding site, with plants deciphering molecular information associated with the feeding herbivore, resulting in the upregulation of the appropriate defenses, and the herbivore avoiding or preventing these defenses from taking effect. Whiteflies can feed on plants without causing significant damage to mesophyll cells, making their detection extra challenging for the plant. However, whiteflies secrete honeydew that ends up on the plant surface at the feeding site and on distal plant parts below the feeding site.

Resistance to sap-sucking insects in modern-day agriculture.

Plants and herbivores have co-evolved in their natural habitats for about 350 million years, but since the domestication of crops, plant resistance against insects has taken a different turn. With the onset of monoculture-driven modern agriculture, selective pressure on insects to overcome resistances has dramatically increased. Therefore plant breeders have resorted to high-tech tools to continuously create new insect-resistant crops.

Improved herbivore resistance in cultivated tomato with the sesquiterpene biosynthetic pathway from a wild relative.

Tomato breeding has been tremendously efficient in increasing fruit quality and quantity but did not focus on improving herbivore resistance. The biosynthetic pathway for the production of 7-epizingiberene in a wild tomato was introduced into a cultivated greenhouse variety with the aim to obtain herbivore resistance. 7-Epizingiberene is a specific sesquiterpene with toxic and repellent properties that is produced and stored in glandular trichomes.

JA-Ile signalling in Solanum nigrum is not required for defence responses in nature.

Jasmonate signalling plays a central role in activating the plethora of responses that are elicited by herbivory. Solanum nigrum plants silenced in the expression of genes involved in jasmonic acid biosynthesis (irlox3), conjugation (irjar4) and perception (ircoi1) were used to study the function of these genes in the field and in the regulation of transcriptional and metabolic responses. In the field, damage from Noctuidea larvae was four- to fivefold higher on irlox3 and ircoi1 than on wild-type (WT) plants, whereas damage to irjar4 plants was similar to WT levels.

Herbivore-associated elicitors: FAC signaling and metabolism.

The recognition of insect and pathogen attack requires the plant's ability to perceive chemical cues generated by the attacker. In contrast to the recognition of microbe-associated molecular patterns and effectors, little is known about the molecular recognition of herbivore-associated elicitors (HAEs) and the signaling mechanisms operating in plants after their perception. HAE perception depends strongly on the natural history of both plants and insects and it is therefore expected that many of the responses induced by different HAEs are specific to the species involved in the interaction.

Regulation of jasmonate metabolism and activation of systemic signaling in Solanum nigrum: COI1 and JAR4 play overlapping yet distinct roles.

• Jasmonates are ubiquitous messengers in land plants essential for the activation of defense responses. However, their signaling properties, accumulation and metabolism vary substantially among species. Solanum nigrum is a wild Solanaceous species developed as a model to study defense responses.

Lipoxygenase-mediated modification of insect elicitors: generating chemical diversity on the leaf wound surface.

Plants can distinguish mechanical damage from larval folivory through the recognition of specific constituents of larval oral secretions (OS) which are deposited on the surface of leaf wounds during feeding. Fatty acid-amino acid conjugates (FACs) are major constituents of the OS of Lepidopteran larvae and they are strong elicitors of herbivore-induced defense responses in several plant species, including the wild tobacco Nicotiana attenuata. When OS from Manduca sexta larvae is deposited on N.

Rapid modification of the insect elicitor N-linolenoyl-glutamate via a lipoxygenase-mediated mechanism on Nicotiana attenuata leaves.

Background: Some plants distinguish mechanical wounding from herbivore attack by recognizing specific constituents of larval oral secretions (OS) which are introduced into plant wounds during feeding. Fatty acid-amino acid conjugates (FACs) are major constituents of Manduca sexta OS and strong elicitors of herbivore-induced defense responses in Nicotiana attenuata plants.

Results: The metabolism of one of the major FACs in M.