title: Synergies and trade-offs between insect and pathogen resistance in maize leaves and roots.
abstract: Determining links between plant defence strategies is important to understand plant evolution and to optimize crop breeding strategies. Although several examples of synergies and trade-offs between defence traits are known for plants that are under attack by multiple organisms, few studies have attempted to measure correlations of defensive strategies using specific single attackers. Such links are hard to detect in natural populations because they are inherently confounded by the evolutionary history of different ecotypes. We therefore used a range of 20 maize inbred lines with considerable differences in resistance traits to determine if correlations exist between leaf and root resistance against pathogens and insects. Aboveground resistance against insects was positively correlated with the plant's capacity to produce volatiles in response to insect attack. Resistance to herbivores and resistance to a pathogen, on the other hand, were negatively correlated. Our results also give first insights into the intraspecific variability of root volatiles release in maize and its positive correlation with leaf volatile production. We show that the breeding history of the different genotypes (dent versus flint) has influenced several defensive parameters. Taken together, our study demonstrates the importance of genetically determined synergies and trade-offs for plant resistance against insects and pathogens.
authors.affiliation: FARCE Laboratory, University of Neuchâtel, Neuchâtel, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Erb
authors.forename: Dirk
authors.initials: D
authors.lastname: Balmer
authors.forename: Elvira S
authors.initials: ES
authors.lastname: De Lange
authors.forename: Georg
authors.initials: G
authors.lastname: Von Merey
authors.forename: Chantal
authors.initials: C
authors.lastname: Planchamp
authors.forename: Christelle A M
authors.initials: CA
authors.lastname: Robert
authors.forename: Gregory
authors.initials: G
authors.lastname: Röder
authors.forename: Islam
authors.initials: I
authors.lastname: Sobhy
authors.forename: Claudia
authors.initials: C
authors.lastname: Zwahlen
authors.forename: Brigitte
authors.initials: B
authors.lastname: Mauch-Mani
authors.forename: Ted C J
authors.initials: TC
authors.lastname: Turlings
mesh_terms: D000818:Animals; D001203:Ascomycota / Q000472:pathogenicity; D018533:Biomass; D001517:Coleoptera / Q000254:growth & development / Q000472:pathogenicity; D020231:Colletotrichum / Q000472:pathogenicity; D005247:Feeding Behavior; D008040:Genetic Linkage; D005838:Genotype; D049452:Green Fluorescent Proteins; D007113:Immunity, Innate; D007814:Larva / Q000254:growth & development / Q000472:pathogenicity; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology / Q000469:parasitology; D018515:Plant Leaves / Q000737:chemistry* / Q000382:microbiology / Q000469:parasitology; D018517:Plant Roots / Q000737:chemistry* / Q000382:microbiology / Q000469:parasitology; D018411:Spodoptera / Q000254:growth & development / Q000472:pathogenicity; D055549:Volatile Organic Compounds / Q000032:analysis / Q000737:chemistry; D003313:Zea mays / Q000235:genetics* / Q000276:immunology / Q000382:microbiology / Q000469:parasitology
chemical_list: D055549:Volatile Organic Compounds; D049452:Green Fluorescent Proteins