| Plants guard themselves against various pathogenic and herbivore attacks by implementing both general and specific induced defenses. Many plants can recognize caterpillar-related elicitors and modify their defense response targeting the specific herbivore. Studies have shown that some plants have a more consistent, overall transcriptional response to generalist herbivores than specialist herbivores. In this study, microarrays were used to examine gene expression of Solanum lycopersicum, tomato plants, after being fed on by Helicoverpa zea (generalist) and Manduca sexta (specialist). H. zea and M. sexta were allowed to feed on tomato leaves for forty-eight hours, then RNA was extracted and aRNA was labeled using Cy-3 and Cy-5 dyes. Microarray data revealed that approximately, 456 expressed genes were significantly altered (P<0.01 ANOVA) by herbivory on tomato plants. Unknown genes account for 36% of altered gene expression. H. zea altered gene expression of 251 genes of the known 289 genes, while M. sexta altered expression of 197 genes (P<0.05 2 tailed t-test). Overall, H. zea herbivory stimulated 163 genes and suppressed 88 genes in comparison to the non-wounded plants. M. sexta herbivory stimulated 119 genes and suppressed 78 genes in comparison to non-wounded. In comparison between H. zea and M. sexta, 29 % of the genes were significantly different. The results showed many similar transcriptional genes in categories such as defense, photosynthesis, biosynthesis, transcription, and stress. |
