Evolution of Protein Molecules

What is ecological speciation

Insect pathogens as biological control agents: Back to the future.

Plants have the capacity to synthesize, accumulate and emit volatiles that may act as aroma and flavor molecules due to interactions with human receptors. These low-molecular-weight substances derived from the fatty acid, amino acid and carbohydrate pools constitute a heterogenous group of molecules with saturated and unsaturated, straight-chain, branched-chain and cyclic structures bearing various functional groups (e.g. alcohols, aldehydes, ketones, esters and ethers) and also nitrogen and sulfur. They are commercially important for the food, pharmaceutical, agricultural and chemical industries as flavorants, drugs, pesticides and industrial feedstocks. Due to the low abundance of the volatiles in their plant sources, many of the natural products had been replaced by their synthetic analogues by the end of the last century. However, the foreseeable shortage of the crude oil that is the source for many of the artificial flavors and fragrances has prompted recent interest in understanding the formation of these compounds and engineering their biosynthesis. Although many of the volatile constituents of flavors and aromas have been identified, many of the enzymes and genes involved in their biosynthesis are still not known. However, modification of flavor by genetic engineering is dependent on the knowledge and availability of genes that encode enzymes of key reactions that influence or divert the biosynthetic pathways of plant-derived volatiles. Major progress has resulted from the use of molecular and biochemical techniques, and a large number of genes encoding enzymes of volatile biosynthesis have recently been reported.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-313X.2008.03446.x

Biosynthesis of plant-derived flavor compounds.

The idea of using species-specific behavior-modifying chemicals for the management of noxious insects in agriculture, horticulture, forestry, stored products, and for insect vectors of diseases has been a driving ambition through five decades of pheromone research. Hundreds of pheromones and other semiochemicals have been discovered that are used to monitor the presence and abundance of insects and to protect plants and animals against insects. The estimated annual production of lures for monitoring and mass trapping is on the order of tens of millions, covering at least 10 million hectares. Insect populations are controlled by air permeation and attract-and-kill techniques on at least 1 million hectares. Here, we review the most important and widespread practical applications. Pheromones are increasingly efficient at low population densities, they do not adversely affect natural enemies, and they can, therefore, bring about a long-term reduction in insect populations that cannot be accomplished with conventional insecticides. A changing climate with higher growing season temperatures and altered rainfall patterns makes control of native and invasive insects an increasingly urgent challenge. Intensified insecticide use will not provide a solution, but pheromones and other semiochemicals instead can be implemented for sustainable area-wide management and will thus improve food security for a growing population. Given the scale of the challenges we face to mitigate the impacts of climate change, the time is right to intensify goal-oriented interdisciplinary research on semiochemicals, involving chemists, entomologists, and plant protection experts, in order to provide the urgently needed, and cost-effective technical solutions for sustainable insect management worldwide.

Sex pheromones and their impact on pest management.

Specific response to herbivore-induced de novo

The female sex pheromone (Z)-4-undecenal mediates flight attraction and courtship in Drosophila melanogaster

The spotted wing Drosophila, Drosophila suzukii, has emerged within the past decade as an invasive species on a global scale, and is one of the most economically important pests in fruit and berry production in Europe and North America. Insect ecology, to a strong degree, depends on the chemosensory modalities of smell and taste. Extensive research on the sensory receptors of the olfactory and gustatory systems in Drosophila melanogaster provide an excellent frame of reference to better understand the fundamentals of the chemosensory systems of D. suzukii. This knowledge may enhance the development of semiochemicals for sustainable management of D. suzukii, which is urgently needed. Here, using a transcriptomic approach we report the chemosensory receptor expression profiles in D. suzukii female and male antennae, and for the first time, in larval heads including the dorsal organ that houses larval olfactory sensory neurons. In D. suzukii adults, we generally observed a lack of sexually dimorphic expression levels in male and female antennae. While there was generally conservation of antennal expression of odorant and ionotropic receptor orthologues for D. melanogaster and D. suzukii, gustatory receptors showed more distinct species-specific profiles. In larval head tissues, for all three receptor gene families, there was also a greater degree of species-specific gene expression patterns. Analysis of chemosensory receptor repertoires in the pest species, D. suzukii relative to those of the genetic model D. melanogaster enables comparative studies of the chemosensory, physiology, and ecology of D. suzukii. 

Comparative transcriptomic assessment of the chemosensory receptor repertoire of Drosophila suzukii adult and larval olfactory organs.

Cette note concerne la description de l'habitus et des genitalia d'une nouvelle espece de Tordeuse (Cydia turcianae n. sp.) de Turquie, capturee au moyen de pieges englues appâtes avec des attractifs sexuels de synthese.

Une nouvelle Tordeuse en Turquie, Cydia turcianae n. sp. (Lepidoptera, Tortricidae)

The present invention relates to a composition for control of a pest in- sect, such as Lepidoptera, said composition comprising an insect pathogen and a microorganism that is naturally associated with the larvae of the pest insect.

Peter Witzgall

Papers

Specific response to herbivore-induced de novo

The female sex pheromone (Z)-4-undecenal mediates flight attraction and courtship in Drosophila melanogaster

Comparative transcriptomic assessment of the chemosensory receptor repertoire of Drosophila suzukii adult and larval olfactory organs.

Une nouvelle Tordeuse en Turquie, Cydia turcianae n. sp. (Lepidoptera, Tortricidae)

A method for controlling insects, using an insect pathogen and a microorganism that is naturally associated with the larvae of the insects