Host plant selection by phytophagous insects pdf merge

Coevolution is the generally accepted theory for the evolution of insecthostplant relationships, however, it can be shown that its main premisses are inadequate. Many people have contributed to the version of the database presented here. However, within the enormous diversity of phytophagous insects, the mechanisms of ecological divergence have been elucidated in few host race systems. Although many insects are dependent on soil for food and shelter, only a few soilborne insects such as weevils, ants, and termites are. Combining mechanisms reduces the likelihood and size.

In the ecological and evolutionary interactions between phytophagous insects and plants jermy and szentesi 2003. Chemicals released from the roots appear to be the. A mechanism of hostplant finding is proposed in which chemical cues start and end the process of hostplant selection and in which the missing central link. Davis and stamps 2004 merged preimaginal condition. If the larvae or nymphs feed on plants, the insect mother usually lays her eggs on a host plant. Evolutionary and mechanistic aspects of insect host plant preference. Ecological speciation via host shifting has contributed to the astonishing diversity of phytophagous insects. Pdf on ecological fitting, plantinsect associations, herbivore host. Current and potential use of phytophagous mites as biological. Mcevoy 2002, it is known that plants influence the evolution of the insects, but it is less clear how much the insects affect the plants.

Insects and phytopathogens differ markedly in their abilities to actively and iteratively choose among individuals within host plant populations. The book also discusses the role of genetic variability in host. Concepts in insect hostplant selection behavior and their. Phytophagous insects from here on simply referred to as insects were collected on native and nonnative plants in two areas. Devising suitable chemically defined diets for phytophagous insects may be a difficult task since it must satisfy the insects nutritional requirements. Deepdyve is the easiest way to get instant access to the academic journals you need.

Sep 25, 2017 in phytophagous insects, adaptation to host plants is thought to play an important role in speciation because host plants provide a site for mating and oviposition and a food resource for progeny 1. Plant viruses alter insect behavior to enhance their spread. Hostplant selection by phytophagous insects contemporary. Concepts in insect hostplant selection behavior and. Dbif is derived from the phytophagous insect data bank see pidb, which was the brainchild of dr lena ward. Special emphasis is addressed to threatened species, phytophagous insects and their natural antagonists and to the symbiotic relationship between xylophagous insects and plant pathogens harmful to forest ecosystems. Host plant selection by insects is often divided into host plant finding. The number of caterpillars is greater in latex free plant species than latex contained plant species diniz et al. Insect parasitology and pathologyphytophagous insects and. Pdf do the mechanisms modulating host preference in. Nevertheless, selection for an accurate assessment of plant quality in herbivorous insects, and especially in polyphagous species, may be constrained by a shortage of information or of the ability to perceive this information.

The sequence of steps in host selection includes habitat location, host location, host acceptance, and host. These artificial diets should however be ideal for growth and development of the test insects at least for many generations. Because phytophagous insects and their green hostplants dominate terrestrial biodiversity, theories which can explain hostplant selection by phytophagous insects would score well under the second criterion. Solms is widely planted as a water ornamental but when environmental conditions are suitable it spreads rapidly obstructing lakes, rivers and rice paddy fields, affecting adversely human activities fishing, water transport and biodiversity. This model can be used to address a number of questions, including the evolution of specialists, generalists, preference hierarchies, and learning. In phytophagous insects, adaptation to hostplants is thought to play an important role in speciation because hostplants provide a site for mating and oviposition and a. Weeds can be defined as plants growing out of place. Specialist versus generalist insect herbivores and plant defense. The food ingested and digested by the insect must fulfil its nutritional requirements for normal growth and development to occur. Adaptive patterns of hostplant selection by phytophagous insects.

Studies comparing how insects find host plants growing in backgrounds of clover and bare soil indicated that it is not chemical, but visual stimuli that govern where the insects land. Sympatric speciation is the splitting of one evolutionary lineage into two without the occurrence of geographic isolation. The sensory systems involved in making the selection are presented together with. Olfactory mechanisms of host selection in phytophagous. The sensory systems involved in making the selection are presented together with relevant functional studies. The ecology of host selection behavior in phytophagous insects.

Most insects are equipped with wings, vision and chemotropisms that govern oriented flight, and. This paper examines if this is so for adaptive theories. Yet the whole process of host plant selection and host plant specificity amongst insects depends on behavior, and selection for behavioral differences must be a prime factor in the evolution of host plant specificity. I outline a conceptual model, the gapeandpinch gap model, of insect response to hostplant trait. View phytophagous insects research papers on academia. Though the relationship between plant host, parasite, and insect host appears simple, in reality it is unknown to what extent different phytomonas species can be spread by different insects or can colonise different plants. These studies are focused on insects which have a relevant role in forest ecosystems, from different points of view. Host plant resistance to insects in integrated pest. Host plant selection in phytophagous insects is a crucial. Scientific name for the insect order that contains butterflies and moths. Olfactory mechanisms of host selection in phytophagous insects. Hostplant selection by phytophagous insects elizabeth a.

Field collections of these organisms may be contaminated with described and undescribed organisms such as plants, hyperparasites, plant pathogens, entopathogens, arthropods, etc. Collier horticulture research international wellesbourne, warwick, united kingdom. Host plant resource quality, insect herbivores and biocontrol. Chapter two external microflora of four phytophagous insect.

For example, water hyacinth eichhornia crassipes mart. Soil provides a structure for a plant to anchor its roots and is a source of nutrition and water necessary for plant growth. The initial results from the field survey suggest that gwss host plant use depends on the type and condition of host plants available as well as the time of year. In comparison to the major ecological and evolutionary questions, it may seem trivial. However, some phytophagous insects have generalist diets, suggesting that maintenance of a diverse diet may confer certain fitness advantages that outweigh diet specialization.

Hostplant seictionby phytophagous insects contemporary topics in entomology series editors thomas a. Yet the whole process of hostplant selection and hostplant specificity amongst insects depends on behavior, and selection for behavioral differences must be a prime factor in the evolution of hostplant specificity. Use of hostplant trait space by phytophagous insects during. Insectplant interactions james ray miller, thomas a. The importance for host shifting of trait differences between alternative host plants is well established, but much less is known about trait variation within hosts. The pea aphid complex as a model of ecological speciation. Why are phytophagous insects typically specialists. Agrawal department of ecology and evolutionary biology, cornell university, e425 corson hall, ithaca, ny 148532701, usa there has been a longstanding hypothesis that specialist and generalist insects interact with plants in distinct ways. The regional institute host plant finding by insects. There are two ways of searching for host taxa contained with dbif. Insect host plant selection in complex environments. Jan, 2010 observations on phytophagous plant eating insects showed that what the insect eats and how much it eats largely determines its economic importance. Can we expect novel chemicals to be more common in some plant groups than others. The nutritional requirements of phytophagous insects.

The signal value of a blend has been shown to be determined by the blend. The concept has been intimately tied to entomology since the 1860s, when benjamin walsh proposed that many host specific phytophagous insects originate by shifting and adapting to new host plant species. As in host selection by other phytophagous insects 104, phytochemical information is particularly important in determining aphid behavior at man y stages of the host selection process 89, 120. Specialized insect herbivores have evolved a high preference for vigorous plant parts because, generally, larval survival is highest on these parts. Because phytophagous insects and their green host plants dominate terrestrial biodiversity, theories which can explain host plant selection by phytophagous insects would score well under the second criterion. Sweeps and visual inspection were different in the quantity of insects detected, although they roughly mirrored one another in monitoring trends in tcah and gwss populations. The potential role of generalist natural enemies is presented as one of the important ecological pressures that select for narrow host range in phytophagous insects, and dominant relative to physiological bases for specialization. Why do entomologists and plant pathologists approach trophic. A mechanism of host plant finding is proposed in which chemical cues start and end the process of host plant selection and in which the missing central link. The authoritative overviews in this volume provide a wealth of practical information on current approaches to the study of insectplant interactions. A general model for host plant selection in phytophagous insects. Encyclopedia of life support systems eolss foraging and food choice in phytophagous insects chapman, r.

Host plant quality and fecundity in herbivorous insects caroline s. Besides chemical content of plant, latex concentration of plant also play a vital role for specific host plant choice by phytophagous insect. Chapter two external microflora of four phytophagous. This book, containing 8 chapters, focuses on the behaviour of hostplant selection by plant feeding insects.

Hostplant selection by phytophagous insects springerlink. This book, containing 8 chapters, focuses on the behaviour of host plant selection by plant feeding insects. During inspections or reinspections of your facility, united states department of agriculture. Plantderived cues play a role in hostplant selection by herbivorous insects and influence behaviors crucial to insect fitness and survival, such as feeding, mating, and oviposition bruce et al. Populations of phytophagous bugs influenced by crop background and wild plants rev. Type a species name, or part of a species name, in the search box and hit the display button. Observations on phytophagous planteating insects showed that what the insect eats and how much it eats largely determines its economic importance. External microflora of four phytophagous insect species 2. The concept has been intimately tied to entomology since the 1860s, when benjamin walsh proposed that many hostspecific phytophagous insects originate by shifting and adapting to new host plant species. Adaptive patterns of hostplant selection by phytophagous. The tritrophic interactions hypothesis, integrating bottomup plantherbivore and topdown herbivorenatural enemies effects, predicts that specialist herbivores should outcompete generalists. The specialization in host use would be one of the scenarios in the evolutionary process of feeding habits in phytophagous insects, because the evolution of host plant use was a highly dynamic process. Insects use a number of sensory cues in host selection including visual, olfactory, gustatory, and tactile stimuli as well as humidity and light intensity bernays and chapman, 1994. We first examined host plant selection preferences of infective reared on virusinfected plants and noninfective reared on virusfree plants r.

Insects are by far the most diverse group of organisms on earth. Pdf in holometabolous phytophagous insects, adult females and larvae determine host plant selection. Many insects, like caterpillars and leaf beetles, feed on plants. Deepdyve is the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Plant architecture and the diversity of phytophagous insects. These cues stimulate receptors, generating sensory input and finally behavioral responses. Variable plants and herbivores in natural and managed systems. Chemical ecology foraging and food choice in phytophagous insects chapman, r. This relationship between plant host, parasite, and insect host is further complicated by the nomenclature of the parasites. Hostplant selection by phytophagous insects nhbs academic.

Mayhewadaptive patterns of host plant selection by phytophagous insects. The tritrophic interactions hypothesis, integrating bottomup plant herbivore and topdown herbivorenatural enemies effects, predicts that specialist herbivores should outcompete generalists. Department of entomology university ofcalifornia riverside. A general model for host plant selection in phytophagous. Some phytophagous insects eat a variety of plant species, while others specialize in eating only one, or just a few. Supporters of the symmetrical view believe that insects affect the population dynamics and. The authoritative overviews in this volume provide a wealth of practical information on current approaches to the study of insect plant interactions. Insects use a number of sensory cues in host selection including visual.

In particular, insects couple complex behavioral repertoires with directed long. Host specialization has been thought to be related with the plant chemistry and natural enemies. Mckey 1980 argues that new chemicals commonly form when two separate biosynthetic pathways merge. Special plant species determines diet breadth of phytophagous. This was first recognized in parasitoids and later in phytophagous insects e. Pdf insect host plant selection in complex environments khu thi.

When selecting host plants, insects may use a variety of senses, such as the sense of smell olfaction, taste, vision, and touch. The first book that focuses on the behaviour of hostplant selection by plantfeeding insects, the authors cover the patterns found in nature and the chemical features of plants that determine host selection. It describes the patterns of host plant use, the chemical features of the host plant which determine their selection, the physiology of the insect sensory system, and insect behaviour, with an emphasis on the mechanism. Soilinhabiting insects also utilize this substrate for part of or for their entire life. Immune benefits from alternative host plants could maintain. Methods described include direct behavioral observation. Phytophagous insects on native and nonnative host plants. Aug 15, 2012 we first examined host plant selection preferences of infective reared on virusinfected plants and noninfective reared on virusfree plants r.