title: The Contrasting Effects of Elevated CO2on TYLCV Infection of Tomato Genotypes with and without the Resistance Gene,Mi-1.2.
abstract: Elevated atmospheric CO2typically enhances photosynthesis of C3 plants and alters primary and secondary metabolites in plant tissue. By modifying the defensive signaling pathways in host plants, elevated CO2could potentially affect the interactions between plants, viruses, and insects that vector viruses.Rgene-mediated resistance in plants represents an efficient and highly specific defense against pathogens and herbivorous insects. The current study determined the effect of elevated CO2on tomato plants with and without the nematode resistance geneMi-1.2, which also confers resistance to some sap-sucking insects including whitefly,Bemisia tabaci. Furthermore, the subsequent effects of elevated CO2on the performance of the vector whiteflies and the severity ofTomato yellow leaf curl virus(TYLCV) were also determined. The results showed that elevated CO2increased the biomass, plant height, and photosynthetic rate of both the Moneymaker and theMi-1.2genotype. Elevated CO2decreased TYLCV disease incidence and severity for Moneymaker plants but had the opposite effect onMi-1.2plants whether the plants were agroinoculated or inoculated viaB. tabacifeeding. Elevated CO2increased the salicylic acid (SA)-dependent signaling pathway on Moneymaker plants but decreased the SA-signaling pathway onMi-1.2plants when infected by TYLCV. Elevated CO2did not significantly affectB. tabacifitness or the ability of viruliferousB. tabacito transmit virus regardless of plant genotype. The results indicate that elevated CO2increases the resistance of Moneymaker plants but decreases the resistance ofMi-1.2plants against TYLCV, whether the plants are agroinoculated or inoculated by the vector. Our results suggest that plant genotypes containing the R geneMi-1.2will be more vulnerable to TYLCV and perhaps to other plant viruses under elevated CO2conditions.
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences Beijing, China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of SciencesBeijing, China; Tourism and Air Service College, Guizhou Minzu UniversityGuizhou, China.
authors.forename: Lichao
authors.initials: L
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences Beijing, China.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of SciencesBeijing, China; University of Chinese Academy of SciencesBeijing, China.
authors.forename: Honggang
authors.initials: H
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences Beijing, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Ge
keywords: Mi-1.2 gene; TYLCV; elevated CO2; resistance; tomato; whitefly