Genet. Biol. 49 , 847 – 855 .
Cowger , C. and Mundt , C. C. ( 2002 ): Aggressiveness of Mycosphaerella graminicola isolates from susceptible and partially resistant wheat cultivars . Phytopathology 92 , 624 – 630 .
Delmotte , F
, F. , Robert , C. and Lannou , C. ( 2012 ): Variation in aggressiveness is detected among Puccinia triticina isolates of the same pathotype and clonal lineage in the adult plant stage . Eur. J. Plant Pathol. 134 , 733 – 743 .
Radwan , O
Pathogenicity including virulence and aggressiveness characteristics was studied on three Plasmopara halstedii (the causal agent of downy mildew) isolates of races 710, 714 and 704 using five single zoosporangium isolates per pathogen isolate. Based on the reaction for the P. halstedii isolates to four sunflower hybrids H1 to H4 varying only in their downy mildew resistance genes, there were differences in virulence spectrum in pathogen isolates. Analysis of five single zoosporangium isolates for P. halstedii isolates showed significant variability within pathogen isolate for all aggressiveness criteria. There were no significant differences among pathogen isolates for all aggressiveness criteria. There were significant differences in the morphology of zoosporangia and sporangiophores for pathogen isolates. Genetic relationships were detected between pathogen isolates using 12 EST-derived markers. There was no intra-race genetic variation, but three genetically-identified groups were detected among pathogen isolates.
The fitness cost associated with virulence was analyzed in a local Plasmopara halstedii (sunflower downy mildew) population. Pathogenic and molecular analyses were carried out on seven pathogen isolates including five progeny isolates of five P. halstedii races arising from two parental ones. P. halstedii isolates showed significant differences for all aggressiveness criteria and important genetic variations. Two cases of relationship (positive and negative) between virulence and aggressiveness for progeny isolates as compared with parental ones were found. Mean virulence cost values varied between 19.9% for positive relationship between the two components of pathogenicity and 50.8% for negative one. For solving the presence of two cases in pathogenicity, the relationship between virulence and aggressiveness among the isolates of three different races localized in the same genetic clade was positive. The hypothesis explaining these cases are discussed.
-based territoriality in water striders, Gerris remigis . Anim. Behav. 42 , 147 – 149 . Chase , I. , Bartolomeo , C. and Dugatkin , L. ( 1994 ): Aggressive interactions and inter-contest interval: how long do winners keep winning? Anim. Behav. 48 , 393