biostudies-literatureUnknown104(25)Will TAphids, which constitute one of the most important groups of agricultural pests, ingest nutrients from sieve tubes, the photoassimilate transport conduits in plants. Aphids are able to successfully puncture sieve tubes with their piercing mouthparts (stylets) and ingest phloem sap without eliciting the sieve tubes' normal occlusion response to injury. Occlusion mechanisms are calcium-triggered and may be prevented by chemical constituents in aphid saliva injected into sieve tubes before and during feeding. We recorded aphid feeding behavior with the electrical penetration graph (EPG) technique and then experimentally induced sieve tube plugging. Initiation of sieve tube occlusion caused a change in aphid behavior from phloem sap ingestion to secretion of watery saliva. Direct proof of "unpProceedings of the National Academy of Sciences of the United States of America10536-41https://www.ebi.ac.uk/biostudies/studies/S-EPMC1965548biostudies-literatureMolecular sabotage of plant defense by aphid saliva.PMC1965548Will TTjallingii WFvan Bel AJThonnessen AfalseMolecular sabotage of plant defense by aphid saliva.Aphids, which constitute one of the most important groups of agricultural pests, ingest nutrients from sieve tubes, the photoassimilate transport conduits in plants. Aphids are able to successfully puncture sieve tubes with their piercing mouthparts (stylets) and ingest phloem sap without eliciting the sieve tubes' normal occlusion response to injury. Occlusion mechanisms are calcium-triggered and may be prevented by chemical constituents in aphid saliva injected into sieve tubes before and during feeding. We recorded aphid feeding behavior with the electrical penetration graph (EPG) technique and then experimentally induced sieve tube plugging. Initiation of sieve tube occlusion caused a change in aphid behavior from phloem sap ingestion to secretion of watery saliva. Direct proof of "unp2007-01-01T00:00:00Z2007 Jun2026-07-15T01:07:04.719Z2026-06-28T03:08:17.993ZS-EPMC19655481755396110.1073/pnas.0703535104