01958nam a2200157 a 450000100080000000500110000800800410001910000200006024500960008026000790017652014610025565000250171670000180174170000240175970000170178318813142011-10-28       2008    bl uuuu     u00u1 u    #d1 aSILVESTRINI, M.  aDefense-related gene expression in response to leaf-miner infection.h[electronic resource]  aIn: INTERNATIONAL CONFERENCE ON COFFEE SCIENCE, 22., 2008, Campinas.c2008  aIn Brazilian coffee plantations, the leaf-miner (Leucoptera coffeella) represents a major threat. Insect control is mainly based on the use of pesticides, as resistant cultivars are not yet available. However, the coffee breeding program of IAC has already selected promising genotypes bearing resistance to the leaf-miner, which was transferred from the diploid species Coffea racemosa. In order to characterize molecular aspects of defense mechanisms associated to the resistance response, expression of key genes was evaluated in coffee leaves, from both resistant and susceptible plants, in response to leaf-miner infection. Infected leavesb were collected at different time-intervals during insect development. Defense-related genes were identified in the Coffee Genome Database, through Blast searches. Gene specific primers were used to amplify corresponding transcripts on sampled leaves using a quantitative RT-PCR approach. Results indicated that there are no significant differences in the expression patterns of evaluated genes when comparing resistant and susceptible infected leaves. Major differences were observed for lipoxygenase, glutathione transferase, protein-kinase receptor and glucanase. However, these differences are mainly associated with expression timing along insect infection rather than with gene regulation, suggesting that resistance to leafminer in coffee may be associated with a previously built basal defense-response.  aLeucoptera Coffeella1 aRAMIRO, D. A.1 aGUERREIRO-FILHO, O.1 aMALUF, M. P.