Host plant finding

Schutz, S., Weissenbecker, B. and Hummel, H. E. (1995). Impact of elevated atmospheric ozone on host plant finding of the Colorado beetle (Leptinotarsa decemlineata Say). Mededelingen van de Faculteit Landbouw Universiteit Gent 60 819-824. 

FINCH, S., Volatile plant chemicals and their effect on host plant finding by the cabbage root fly. Entomol. Exp. Appl., 1978,24, 150-159. 

WHEN AND WHY USE CHEMICALS IN HOST-PLANT FINDING AND ACCEPTING... 

Klingauf, F.. In Aphids Their Biology, Natural Enemies and Control. Minks, A. K and Harrewijn, P., Eds. Host Plant Finding and Acceptance Elsevier New York, NY, 1987 Vol. 2A p 209-233. 

Finch, S. 1986. Assessing host-plant finding by insects. In Insect-Plant Interactions, eds., J.R. Miller T.A. Miller, pp. 23-63, Springer-Verlag, New York. 

A fine example of this problem Is the detection of an NP responsible for one species of insect finding its host plant. An analysis of the volatile chemicals made by the plant showed some chemicals made in large amounts, others in smaller amounts and some in minute amounts. By analysing the nerve output of the insect s olfactory cells to these chemicals, the insect was found to be responding to one of the very minor chemicals. 

Chapters in this volume consider how plants use chemicals to defend themselves from insect herbivores the complexity of floral odors that mediate insect pollination tritrophic interactions of plants, herbivores, and parasitoids, and the chemical cues that parasitoids use to find their herbivore hosts the semiochemically mediated behaviors of mites pheromone communication in spiders and cockroaches the ecological dependence of tiger moths on the chemistry of their host plants and the selective forces that shape the pheromone communication channel of moths. 

One perceives from the world only what one has been prepared to perceive. In humans and in most mammals, different senses are used to make sense of life. In contrast, in insects, chemical senses involving odorants and contact chemosensory molecules play a vital role. The olfactory system is the primary sense insects use in analyzing the environment, in crucial tasks such as finding food, nesting, mating and in conspecifics. Contact chemosensation is used especially to analyze specific substrates to assist in the identification of suitable oviposition sites, the recognition of host plants, the selection of tastants and the search for further nutrient chemicals. Dedicated to survival, both olfactory and contact chemosensory systems in insects have developed to extremely high levels of sensitivity and selectivity. 

Most insects are herbivores, and adaptation to host plants and their chemistry is often very close and complex 1,4,10,14,15,28-33, 494-496,503). Whereas insects rely on plants for food, many plants need insects for pollination and seed dispersal. In the latter context we often find that plants attract insects by chemical means (colors, fragrances, sugars, amino acids). At the same time, other secondary metabolites are employed to discourage the feeding on flowers and seeds. 

Host plant-specific specialists occur within bacteria, fungi, and herbivores. The interaction of the former two groups is a central topic for plant pathologists. They often find that susceptible and nonsusceptible microbe strains exist. In most cases, it is not known how these microbial specialists achieved a relationship with the host plant chemistry, for example, whether they degrade secondary metabolites or whether they simply toler-... 

A key question is How do we find lures. There are two main routes. In one of these—the isolation approach—an attempt is made to isolate a natural substance known to be an attractant, determine its chemical structure, and synthesize the active ingredient. This approach is exemplified by the work relating to sex attractants of the gypsy moth l 4y 25y 30y 56y 68, 10) and the silkworm moth [Bombyx mori (L.)] (27, 28, 29, 51, 58). However, the attractant may be a host plant 43, 91, 98, 99), or animal (22, 26), or even a substance like petroleum oil 8, 86). 

Most fungi reproduce by spores, which function about the same way as seeds. Fungal spores are often miaoscopic in size and are produced in tremendous numbers. Most of them die because they do not find a host plant to attack. Some can survive for weeks or months without a host plant. Water or high humidity (above 90 percent) are nearly always essential for... 

Insects eat an incredible variety of foods leaves, roots, plant sap, wood, other insects, other arthropods, blood of birds and mammals, decaying plant material, pollen, nectar, dung, particles of algae, and even fungi. Some, like cockroaches, can digest nearly anything they can get their mandibles (jaws) on, while others must find a particular species of plant to eat or they will die. The disappearance of many butterfly species is due to the loss of their particular host plants as wild areas are cultivated or paved. 

Jf you have damaged plants and aren t sure what insect is causing the injury, use this table to narrow the list of possible culprits. Look for the description of damage symptoms in the left-hand column that matches your plant s symptoms. Next, find the appropriate category of host plants that... 

The sugarcane rootstalk borer weevil is attracted to aggregate by food, others of its kind, and by their frass.161 If the pheromones involved can be identified, they can be used in traps. Insects interact with the terpenes in plants in a variety of ways.162 The insect may find the host plant in this way, either to eat it, or to lay eggs in it. Terpenes such as pulegone (11.34),163 thujone, camphor, and citronellal repel insects (11.35). Linalool has been used as an insecticide on house plants. 

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