Insect regurgitant and wounding elicit similar defense responses in poplar leaves: not something to spit at?
How plants perceive insect attacks is an area of active research. Numerous studies have shown that regurgitant from feeding insects elicits a defense response in plants, which is often assumed to be distinct from a wound response. We have characterized the inducible defense response in hybrid poplar and found it to be qualitatively similar between wounding and application of regurgitant from forest tent caterpillar. We suggest that this is likely attributable to our wounding treatment which is much more intense compared to most other studies. These overlapping responses appear to be activated via jasmonic acid signaling, and we speculate that they are both triggered by elicitors of plant origin. Wounding would release such elicitor molecules when leaf cells are disrupted, and regurgitant may contain them in a modified or processed form. This hypothesis could explain why some other necrosis-inducing stresses also induce herbivore defense genes.
Major
Ian T
IT
Centre for Forest Biology & Biology Department; University of Victoria; Victoria, Canada.
Constabel
C Peter
CP
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15939667
Plant Physiol. 2006 Sep;142(1):352-63
16829584
New Phytol. 2002 Nov;156(2):145-169
33873279
Plant Physiol. 2005 Mar;137(3):1160-8
15728342
New Phytol. 2006;172(4):617-35
17096789
Plant Physiol. 2000 Sep;124(1):285-95
10982443
Plant Cell. 2004 Nov;16(11):3132-47
15494554
Plant Physiol. 2006 Apr;140(4):1222-32
16428598
Proc Natl Acad Sci U S A. 2006 Jun 6;103(23):8894-9
16720701
Mol Ecol. 2004 Aug;13(8):2421-33
15245414
Genetics. 2006 Dec;174(4):1811-24
17028338
Plant Physiol. 2002 Jun;129(2):661-77
12068110
Plant Cell Environ. 2006 Aug;29(8):1545-70
16898017
Plant Physiol. 2003 Aug;132(4):2098-107
12913164
Arch Insect Biochem Physiol. 2005 Feb;58(2):128-37
15660363