The chemosensory ecology of a foraging hawkmoth

While foraging, all animals need to balance their energetic cost and gains. The sensory systems provide the information, which form the bases for these energy-economic decisions and thus, link the sensory input directly to the fitness of the animal. Night-active hawkmoth species particularly rely on their olfactory system which detects the volatiles emitted by those plants visited by the moth. This dissertation examined the olfactory system and the foraging decisions of the hawkmoth Manduca sexta to gain further insights into the ecological pressures which might have directed the evolution of the olfactory system in hawkmoths and their coevolution with the flowers they visit. In order to address these questions we first studied the odour guided flight of M. sexta to flowers of different Nicotiana species, which matched the length of the moth proboscis to different degrees. It was found that the moth already selected the best matching flower at the first encounter with the odour plume emitted by this flower and that foraging on these matching flowers did result in the highest energy gain for the moth. We could further show that M. sexta recognise a plant headspace based on the composition of this blend rather than on its concentration. However, flower odours are readily intermixed with other volatiles and their detection is hence most reliable close to the flower. Here, we show that the moth uses specific olfactory neurons on the tip of its proboscis to evaluate flowers, and that this close range detection is crucial both for foraging as well as pollination. Finally, the effect of flower orientation on the foraging of M. sexta was analysed, finding that the synchronisation of floral volatiles and orientation is crucial for this moth-plant interaction. Taken together our studies on the foraging of hawkmoth might not only help to gain new insights into the evolution of sensory systems, but also on how these systems shapes the interaction between different species

Radar, Insect Population Ecology, and Pest Management

Discussions included: (1) the potential role of radar in insect ecology studies and pest management; (2) the potential role of radar in correlating atmospheric phenomena with insect movement; (3) the present and future radar systems; (4) program objectives required to adapt radar to insect ecology studies and pest management; and (5) the specific action items to achieve the objectives

From Insect Pheromones to Mating Disruption

The present book, a reprint of the successful Insects Special Issue "From Insect Pheromones to Mating Disruption: Theory and Practice", includes laboratory and field studies dealing with insect pheromones, as well as on mating disruption efficacy against insect species of economic importance, with special reference to the development and optimization of mating disruption approaches, their mechanisms of action, and possible non-target effects

The olfactory pathway of the red flour beetle Tribolium castaneum and its comparison to other Coleoptera

Insects are the most successful animals on earth. They have a great impact on almost all terrestrial ecosystems, affecting mankind by beneficial and harmful ways like facilitating vast amounts of human food production via pollination or by being a devastating pest to agricultural products and food stocks as well as spreading diseases. Among insects, Coleoptera are the most divers and species richest order, containing vast quantities of pest species. The majority of insects depends heavily on their olfactory system to master most tasks they encounter during their lifespan, like finding food sources, hosts, native populations, and mates, or to avoid predators. Despite the diversity and species richness of beetles, as well as their impact as pest, not much is known about the olfactory system of these animals. To investigate the olfactory system of Coleoptera, we analyzed 1) the olfactory pathway of one model organism in highly detail and 2) we examined particular brain regions of the olfactory system of many beetles and insects and compared them with each other. 1: For the highly detailed analysis of the olfactory pathway of one species we worked with the red flour beetle Tribolium castaneum, an already established model organism in some fields of biology like in development and evolution. Experiments requiring genetic methods had been performed in cooperation with the Georg-August-Universität Göttingen. Based on immunohistochemical stainings we created 3D-reconstructions of adult and larval brains, helping us to identifying the most prominent brain structures, as a starting point for following projects. On this basis, we decrypted the olfactory pathway of the adult T. castaneum. This includes A) morphological data of the antenna with its olfactory sensilla and neuroanatomical data of the brain structures involved in olfaction, as well as B) molecular data from antennal structures involved in olfaction (like olfactory respectively gustatory receptors or olfactory binding proteins). Furthermore, we identified neuropeptide families within the primary and one higher integration center for olfaction - namely the antennal lobe (AL) and mushroom body (MB) - of T castaneum. Additionally, we investigated one neuropeptide family and its respective receptor within the brain of T. castaneum in detail. We compared this neuropeptide family and its receptor with two structurally similar and closely related neuropeptide families and their receptors. 2: The second focus of this thesis was the investigation of single features of the olfactory pathway and their comparison between different coleopteran-, respectively insect species. In one project we studied the distribution of eight neuropeptide families within the MB of 24 different insect species and compared them with each other, looking for potential evolutionary correlations. Furthermore, we analyzed the AL of 63 different Coleoptera and found an unusual architecture of the AL in some species. In a related project we investigated such an unusual architectured AL of one species (the small hive beetle Aethina tumida) highly detailed. In this thesis, the brain architecture and especially the olfactory system of Coleoptera had been investigated for the first time in high detail. We revealed new insights regarding the olfactory (respectively chemoreceptive) pathway of these animals. The findings will help to establish T. castaneum as the fist coleopteran model organism for insect neuroscience and in particular for insect olfaction. The single projects of this thesis will be described in-depth in the following eight chapters

Area-wide Integrated Pest Management

Over 98% of sprayed insecticides and 95% of herbicides reach a destination other than their target species, including non-target species, air, water and soil. The extensive reliance on insecticide use reduces biodiversity, contributes to pollinator decline, destroys habitat, and threatens endangered species. This book offers a more effective application of the Integrated Pest Management (IPM) approach, on an area-wide (AW) or population-wide (AW-IPM) basis, which aims at the management of the total population of a pest, involving a coordinated effort over often larger areas. For major livestock pests, vectors of human diseases and pests of high-value crops with low pest tolerance, there are compelling economic reasons for participating in AW-IPM. This new textbook attempts to address various fundamental components of AW-IPM, e.g. the importance of relevant problem-solving research, the need for planning and essential baseline data collection, the significance of integrating adequate tools for appropriate control strategies, and the value of pilot trials, etc. With chapters authored by 184 experts from more than 31 countries, the book includes many technical advances in the areas of genetics, molecular biology, microbiology, resistance management, and social sciences that facilitate the planning and implementing of area-wide strategies. The book is essential reading for the academic and applied research community as well as national and regional government plant and human/animal health authorities with responsibility for protecting plant and human/animal health

Area-wide Integrated Pest Management

Extensive reliance on insecticides reduces biodiversity, contributes to pollinator decline, destroys habitat and threatens endangered species. This book offers a more effective application of the Integrated Pest Management (IPM) approach, on an area-wide (AW) or population-wide (AW-IPM) basis. It addresses the importance of problem-solving research, planning and baseline data collection, integrating tools for appropriate control strategies, and pilot trials. The 48 chapters authored by 184 experts cover advances in genetics, molecular biology, biological control, resistance management, modelling, automated surveillance and unmanned aerial release systems