Nitrogen deficiency increases volicitin-induced volatile emission, jasmonic acid accumulation, and ethylene sensitivity in maize.

Abstract

Insect herbivore-induced plant volatile emission and the subsequent attraction of natural enemies is facilitated by fatty acid-amino acid conjugate (FAC) elicitors, such as volicitin [N-(17-hydroxylinolenoyl)-L-glutamine], present in caterpillar oral secretions. Insect-induced jasmonic acid (JA) and ethylene (E) are believed to mediate the magnitude of this variable response. In maize (Zea mays) seedlings, we examined the interaction of volicitin, JA, and E on the induction of volatile emission at different levels of nitrogen (N) availability that are known to influence E sensitivity. N availability and volicitin-induced sesquiterpene emission are inversely related as maximal responses were elicited in N-deficient plants. Plants with low N availability demonstrated similar volatile responses to volicitin (1 nmol plant(-1)) and JA (100 nmol plant(-1)). In contrast, plants with medium N availability released much lower amounts of volicitin-induced sesquiterpenes compared with JA, suggesting an alteration in volicitin-induced JA levels. As predicted, low N plants exhibited greater sustained increases in wound- and volicitin-induced JA levels compared with medium N plants. N availability also altered volicitin-E interactions. In low N plants, E synergized volicitin-induced sesquiterpene and indole emission 4- to 12-fold, with significant interactions first detected at 10 nL L(-1) E. Medium N plants demonstrated greatly reduced volicitin-E interactions. Volicitin-induced sesquiterpene emission was increased by E and was decreased by pretreatment the E perception inhibitor 1-methylcyclopropene without alteration in volicitin-induced JA levels. N availability influences plant responses to insect-derived elicitors through changes in E sensitivity and E-independent JA kinetics.

• Authors: Eric A Schmelz, Hans T Alborn, Juergen Engelberth, James H Tumlinson
• Journal: Plant physiology (Plant Physiol) Vol. 133 Issue 1 Pg. 295-306 (Sep 2003) ISSN: 0032-0889 [Print] United States
• PMID: 12970495 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Cyclopentanes
• Ethylenes
• Oxylipins
• Sesquiterpenes
• volicitin
• alpha-Linolenic Acid
• Glutamine
• jasmonic acid
• ethylene
• Nitrogen

Topics

• Animals
• Cyclopentanes (metabolism)
• Ethylenes (pharmacology)
• Glutamine (analogs & derivatives, pharmacology)
• Immunity, Innate
• Insecta (growth & development)
• Nitrogen (deficiency, pharmacology)
• Oxylipins
• Plant Diseases (parasitology)
• Sesquiterpenes (metabolism)
• Signal Transduction (drug effects, physiology)
• Stress, Mechanical
• Volatilization (drug effects)
• Zea mays (drug effects, metabolism, parasitology)
• alpha-Linolenic Acid (analogs & derivatives, pharmacology)