Diverse parasite taxa share hosts both at the population level and within individual hosts, and their interactions, ranging from competitive exclusion to facilitation, can drive community structure and dynamics. Emergent pathogens have the potential to greatly alter community interactions. We found that an emergent fungal entomopathogen dominated pre-existing lethal parasites in populations of ...

The potato psyllid, Bactericera cockerelli (šulc), has been detrimental to potato, tomato, and other solanaceous crop production in many countries. Management of B. cockerelli is dominated by frequent insecticide applications, but other approaches need consideration, including biological control. The sole arrhenotokous ectoparasitoid of nymphal potato psyllids is Tamarixia triozae (Burks) (Hyme...

Experimental studies have shown that parasites can reduce host density and even drive host population to extinction. Existing mathematical models for parasite-host interactions, while can address the host density reduction scenario, fail to explain such deterministic extinction phenomena. In order to understand the parasite induced host extinction, Ebert et al. (2000) formulated a plausible but...

Ecological processes that determine the abundance of species within ecological communities vary across space and time. These scale-dependent processes are especially important when they affect key members of a community, such as ecosystem engineers that create shelter and food resources for other species. Yet, few studies have examined the suite of processes that shape the abundance of ecosyste...

Interactions of the parasitoids Palmistichus elaeisis Delvare & LaSalle and Trichospilus diatraeae Cherian & Margabandhu (Hymenoptera: Eulophidae) with its alternative host Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae) affect the success or failure of the mass production of these parasitoids for use in integrated pest management programs. The aim of this study was to evaluate changes ...

Multiple invasions (MIs) or infections, i.e. those by more than 1 parasite in the same erythrocyte, could be the result of parasite density or, alternatively, to parasite-related factors or host-related factors. According to the last possibility, to our knowledge, only 3 laboratory studies of malaria have found an increase in the occurrence of MIs when antibodies to parasite antigens were prese...

Natural parasitoid systems exhibit considerable variation in their life history properties yet little is known about the effects of development time on parasitoid fitness or of the conditions that might select for rapid development at the expense of reduced parasitoid growth. In this study the techniques of adaptive dynamics are applied to a discrete time host-parasitoid model to examine the ev...

To determine the role of natural enemies and host-plant quality in the population dynamics of Cameraria hamadryadella. we examined survival patterns and causes of mortality of a single population of C. hamadryadella during the epidemic vcars of 1982-1984 and the endemic years of 198,S-1990. C hamadryadella is a leat-mining microlepidopteran whose primary host is white oak, Quercus alba. Populat...