It is generally correct to think of plants as the hearty autotrophs, gamely harnessing photons to make food and existing perennially (or annually) at the bottom of the food chain. However, thousands of plant species have lost the ability to feed themselves and have become adapted, instead, to live as parasites of other plants. Not surprisingly, these parasitic plants, especially witchweed root ...

This article summarizes the knowledge to date on biology of the potato leafhopper, Empoasca fabae (Harris), including its distribution, development, migration, agricultural host plants, and mechanics of injury to host plants. Damage to alfalfa, potatoes, soybeans, and snap beans, and treatment guidelines, are summarized. Particular attention is given to integrated pest management options in alf...

Ovipositing females of the pipevine swallowtail butterfly, Battus philenor, detect the presence of eggs laid by other females on their host plants . The presence of eggs on a plant inhibits oviposition by a female that discovers it . The selection pressure responsible for the evolution and maintenance of discrimination against plants with eggs appears to be lower survival from egg to adult of e...

The sweetpotato whitefly, Bemisia tabaci biotype B is extremely polyphagous with >600 species of host plants. We hypothesized that previous experience of the whitefly on a given host plant affects their host selection and performance on the plants without previous experience. We investigated the host selection for feeding and oviposition of adults and development and survival of immatures of th...

The Alaskan swallowtail butterfly, Papilio machaon aliaska (Lepidoptera: Papilionidae), uses three plant species as host plants. Cnidium cnidiifolium (Turcz.) Schischk. belongs to the family Apiaceae, the ancestral host-plant family of the P. machaon group. Artemisia arctica Less. and Petasites frigidus (L.) Franch, in contrast, belong to the distantly related Asteraceae family and were coloniz...

Most aphids are highly specialized on one or two related plant species and generalist species often include sympatric populations adapted to different host plants. Our aim was to test the hypothesis of the existence of host specialized lineages of the aphid Melanaphis sacchari in Reunion Island. To this end, we investigated the genetic diversity of the aphid and its association with host plants...

The rust fungi are a monophyletic group of approximately 7000 species in the basidiomycota and are highly specialized obligate parasites of plants. The life cycle of rusts can be complex. Some rusts have up to five spore stages that alternate between haploid and dikaryotic nuclear conditions and that can occur on two taxonomically unrelated host plants. The rusts have evolved specialized struct...

Aphids and other phytophagous insects often show intra-specific variations in relation to host plant utilization. In several instances, intra-species variations lead to host-plant specialization. These are considered to be important source of speciation. In a recent study ( Foottit RG et al. 2010 . Zootaxa 2358: 25–38) two forms of the banana aphid, Pentalonia nigronervosa f typica Coquerel (He...

abstract during a survey for detection of pvs in potato fields in northern khorasan province, some tubers from the plants which have been already marked and showing mosaic, rugosity, undulation on leaf margins, little leaf and slightly vein deepening, were collected in bodjunrd region, also, some tubers from potato fields of mashhad, chenaran, ghoochan, faruj and shirvan regions were randomly c...