| Title: | "Nitrogen deficiency increases volicitin-induced volatile emission, jasmonic acid accumulation, and ethylene sensitivity in maize" |
| Author(s): | Schmelz EA; Alborn HT; Engelberth J; Tumlinson JH; |
| Address: | "Center of Medical, Agricultural, and Veterinary Entomology, U.S. Department of Agriculture, Agricultural Research Service, Gainesville, FL 32608, USA. eschmelz@gainesville.usda.ufl.edu" |
| ISSN/ISBN: | 0032-0889 (Print) 1532-2548 (Electronic) 0032-0889 (Linking) |
| 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" |
| Keywords: | "Animals Cyclopentanes/*metabolism Ethylenes/*pharmacology Glutamine/*analogs & derivatives/*pharmacology Immunity, Innate Insecta/growth & development Nitrogen/deficiency/*pharmacology Oxylipins Plant Diseases/parasitology Sesquiterpenes/*metabolism Signa;" |
| Notes: | "MedlineSchmelz, Eric A Alborn, Hans T Engelberth, Juergen Tumlinson, James H eng Research Support, U.S. Gov't, Non-P.H.S. 2003/09/13 Plant Physiol. 2003 Sep; 133(1):295-306. doi: 10.1104/pp.103.024174" |
