Eight species of the genus Cercospora from different localities in Northern provinces of Iran were obtained and examined during spring-autumn 2010. Cercospora acnidae (from Amaranthus chlorostachys var. chlorostachys), C. beticola (from Beta vulgaris), C. iridis (from Iris sp.), C. lactucae-sativae (from Lactuca sativa), C. mercurialis (from Mercurialis annua), C. sorghi (from Sorghum halepense...

A long-standing hypothesis asserts that plant-feeding insects specialize on particular host plants because of negative interactions (trade-offs) between adaptations to alternative hosts, yet empirical evidence for such trade-offs is scarce. Most studies have looked for microevolutionary performance trade-offs within insect species, but host use could also be constrained by macroevolutionary tra...

Most studies on plant defenses against insect herbivores investigate direct and indirect plant defenses independently. However, these defenses are not necessarily mutually exclusive. Plant metabolites can be transmitted through the food chain and can also affect the herbivore’s natural enemies. A conflict may arise when a natural enemy is attracted to a plant that is suboptimal in terms of its ...

Determining the macroevolutionary importance of plant chemistry on herbivore host shifts is critical to understanding the evolution of insect-plant interactions. Molecular phylogenies of the ancient and speciose Blepharida (Coleoptera)-Bursera (Burseraceae) system were reconstructed and terpenoid chemical profiles for the plant species obtained. Statistical analyses show that the historical pat...

Host plant selection by insects is often divided into „host plant finding‟ and „host plant acceptance.‟ While the two are easy to separate conceptually, in practice, they are really part of a continuum of three, rather than two, inextricably bonded links. However, the central link of host plant finding, thought previously to be governed by volatile chemicals, has, until now, proved intractable ...

Throughout evolution, a wide number of organisms specialized in parasitizing plants. Plants are not exceptions; certain plant species evolved as parasites of their own kind. Parasitic angiosperms evolved at least 12 times and show various lifestyles. For example, facultative parasitic plants can complete their life cycle and produce seeds without hosts, whereas obligate parasitic plants totally...

agrobacterium tumefaciens is capable of gene transfer to both plant and non-plant organisms. indeed, upon infection of eukaryotic cells, agrobacterium tumefaciens transfers a piece of its tumor inducing (ti)-plasmid, called t-dna, to the host cell nucleus, which subsequently integrates into the host genome. the vird2 virulence protein which has relaxase endonuclease activities covalently binds ...

The difficulties specialized phytophagous insects face in finding habitats with an appropriate host should constrain their dispersal. Within the concept of metacommunities, this leads to the prediction that host-plant specialists should sort into local assemblages according to the local environmental conditions, i.e. habitat conditions, whereas assemblages of host-plant generalists should depen...

Microbial diversity is generally far higher than plant diversity, but the relationship between microbial diversity and plant diversity remains enigmatic. To shed light on this problem, we examined the diversity of a key guild of root-associated microbes,that is, ectomycorrhizal (EM) fungi along a plant diversity gradient in a Chinese subtropical forest. The results indicated that EM fungal dive...

Divergent selection between environments can result in changes to the behavior of an organism. In many insects, volatile compounds are a primary means by which host plants are recognized and shifts in plant availability can result in changes to host preference. Both the plant substrate and microorganisms can influence this behavior, and host plant choice can have an impact on the performance of...