Parasitoids

Parasitoids lay their eggs on or in the bodies of other species of insect, and the parasitoid larvae develop by feeding on the host, causing its eventual death. Known for a long time to applied biologists for their importance in regulating the population densities of economic pests, parasitoids have recently proven to be valuable tools in testing many aspects of evolutionary theory. This book synthesizes the work of both schools of parasitoid biology and asks how a consideration of evolutionary biology can help us understand the behavior, ecology, and diversity of the approximately one to two million species of parasitoid found on earth. After a general introduction to parasitoid natural history and taxonomy, the first part of the book treats the different components of the reproductive strategy of parasitoids: searching for a host, host selection, clutch size, and the sex ratio. Subsequent chapters discuss pathogens and non-Mendelian genetic elements that affect sexual reproduction; evolutionary aspects of the physiological interactions between parasitoid and host; mating strategies; life history theory and community ecology. A special effort is made to discuss the theoretical background to the subject, but without the use of mathematics.

Written by a team of leading international specialists, Behavioral Ecology of Insect Parasitoids examines the optimal behaviors that parasitoids exhibit in order to maximize long term offspring production. It is an essential reference for research scientists and students studying these fascinating insects or for anyone involved in using parasitoids in biological control programs. Reviews topical issues, including cutting edge research on parasitoid decision making and the implications for biological control Explores applications in other fields, provides information on the latest research methods, and includes helpful case studies and statistical tools Creates a deeper understanding of the link between behavioural strategies and host mortality, resulting in more efficient selective pest management programs “Overall, this is a fascinating volume that provides a significant contribution to the literature on parasitoid insects. It goes a long way toward providing insights into numerous aspects of parasitoid behavior and will stimulate a diversity of future projects, something that should be the goal of any such text. I highly recommend Wajnberg et al. for all of those working on the biology or evolution of parasitoids.” Palaios 2009

Most insect parasitoids are related to two insect orders, Diptera and Hymenoptera, some having a specific host while others have a vast host range. As such, the opening chapter of Parasitoids: Biology, Behavior and Ecology discusses the influence of host preference and host specificity in biological control programs and their role in different biological control methods.The behavioral responses of parasitoids can determine the efficiency of a parasitoid species to control host pests. The functional response is one of the most important behavioral responses. The authors show that type II functional response is more common than the other types (I, III, IV and V) of functional response for most parasitoid species. In some research, type III functional response was also reported for parasitoids.The closing study hypothesized that conditioned parasitoids will parasitize more target hosts compared with individuals without prior conditioning. In conditioning experiments, females of the wasp Trichogramma cacoeciae, a generalist egg parasitoid, oviposited in Lobesia botrana eggs while exposed to L. botrana's synthetic sex pheromone. Contrary to the hypothesis, this treatment failed to increase the parasitism rate in a subsequent exposure to the conditioned olfactory cue.

Their natural enemies largely determine the population size and dynamic behavior of many plant-eating insects. Any reduction in enemy number can result in an insect outbreak. Applied biological control is thus one strategy for restoring functional biodiversity in many agroecosystems. Predators and Parasitoids addresses the role of natural enemies i

Egg Parasitoids in Agroecosystems with emphasis on Trichogramma was conceived to help in the promotion of biological control through egg parasitoids by providing both basic and applied information. The book has a series of chapters dedicated to the understanding of egg parasitoid taxonomy, development, nutrition and reproduction, host recognition and utilization, and their distribution and host associations. There are also several chapters focusing on the mass production and commercialization of egg parasitoids for biological control, addressing important issues such as parasitoid quality control, the risk assessment of egg parasitoids to non-target species, the use of egg parasitoids in integrated pest management programs and the impact of GMO on these natural enemies. Chapters provide an in depth analysis of the literature available, are richly illustrated, and propose future trends.

Much is known about the biology of Drosophila parasitoids, which is why they are used as a model for studying other parasitoids. This book brings together the different fields of research that can be explored, thanks to the "Drosophila parasitoid" model. It shows how the complementary knowledge arising from different approaches is inspiring the development of new areas of research on this biological model. It also discusses techniques and methods specifically adapted to the study of larval parasitoid species.

The Ichneumonoidea is a vast and important superfamily of parasitic wasps, with some 60,000 described species and estimated numbers far higher, especially for small-bodied tropical taxa. The superfamily comprises two cosmopolitan families - Braconidae and Ichneumonidae - that have largely attracted separate groups of researchers, and this, to a considerable extent, has meant that understanding of their adaptive features has often been considered in isolation. This book considers both families, highlighting similarities and differences in their adaptations. The classification of the whole of the Ichneumonoidea, along with most other insect orders, has been plagued by typology whereby undue importance has been attributed to particular characters in defining groups. Typology is a common disease of traditional taxonomy such that, until recently, quite a lot of taxa have been associated with the wrong higher clades. The sheer size of the group, and until the last 30 or so years, lack of accessible identification materials, has been a further impediment to research on all but a handful of ‘lab rat’ species usually cultured initially because of their potential in biological control. New evidence, largely in the form of molecular data, have shown that many morphological, behavioural, physiological and anatomical characters associated with basic life history features, specifically whether wasps are ecto- or endoparasitic, or idiobiont or koinobiont, can be grossly misleading in terms of the phylogeny they suggest. This book shows how, with better supported phylogenetic hypotheses entomologists can understand far more about the ways natural selection is acting upon them. This new book also focuses on this superfamily with which the author has great familiarity and provides a detailed coverage of each subfamily, emphasising anatomy, taxonomy and systematics, biology, as well as pointing out the importance and research potential of each group. Fossil taxa are included and it also has sections on biogeography, global species richness, culturing and rearing and preparing specimens for taxonomic study. The book highlights areas where research might be particularly rewarding and suggests systems/groups that need investigation. The author provides a large compendium of references to original research on each group. This book is an essential workmate for all postgraduates and researchers working on ichneumonoid or other parasitic wasps worldwide. It will stand as a reference book for a good number of years, and while rapid advances in various fields such as genomics and host physiological interactions will lead to new information, as an overall synthesis of the current state it will stay relevant for a long time.