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Research Papers in Chemical Ecology

All Publications by John Byers John A. Byers and Coauthors
Host Plant Selection:
1. Avoidance of nonhost tree and plant volatiles by pine bark beetles
Study area near Sjöbo, Sweden, in Scotch Pine Forest

2. Avoidance of host and nonhost tree volatiles by pine bark beetles
Study area near Sjöbo, Sweden, in Scotch Pine Forest

3. Birch volatiles inhibit spruce bark beetles
forest of birch (Betula pendula and B. pubescens) and Norway spruce (Picea abies), Torsby, Sweden

4. Attraction to ethanol and monoterpenes

5. Host- and mate-recognition
Pityogenes chalcographus on Norway spruce bark (with young needles)

6. Olfactory recognition of host-tree susceptibility
Tomicus piniperda on Scotch pine (bark cut away with resin exudation)

7. Host unsuitability recognized in flight

8. Attraction of elm bark beetle to elm

9. Attraction of tea aphid to tea

Pheromone Biosynthesis:
1. Pheromone precursor in 5 Pine species
Digger (left, background) and ponderosa pine (right) in California

2. Myrcene from host tree as pheromone precursor

3. Symbiotic microorganisms and pheromone biosynthesis?
Ips paraconfusus on synthetic diet

4. Sex, maturity, and host-tree effects on biosynthesis
mature and callow Ips paraconfusus

5. Ips paraconfusus pheromone biosynthesis
Ips paraconfusus hindgut vs. blue sewing thread

6. Male-specific biosynthesis of inhibitor

Alarm and Defensive Chemicals:
1. Cost of aphid alarm pheromone production
cotton aphids on cotton

2. Defensive chemicals of plant bug Lygus hesperus
Lygus hesperus plant bugs, male and female, on cotton leaf

3. Individual variation of alarm and defensive semiochemicals
Harvester ant Pogonomyrmex barbatus and braconid Leiophron uniformis

Competition and Reproductive Isolation:
1. Mutual avoidance of competition
Spacing apart of Pityogenes chalcographus and Ips typographus attacks on Norway spruce

2. Review: Avoiding competition in bark beetles

3. Female bark beetle avoids trans-verbenol and competition
Paper carton trap above sticky trap

4. Regulation of competition in Ips paraconfusus by pheromone
boring dust (frass) from entrance hole of Ips paraconfusus in ponderosa pine

5. Interspecific inhibition and competition
John Byers shinnying up ponderosa pine as a graduate student at Berkeley

6. Reproductive isolation by olfaction
Rotating traps in Scotch pine forest in Skåne (Sweden)

7. Lygus plant bug sex pheromones
Lygus hesperus (male) and Lygus lineolaris (male)

Mating and Colonization Ecology:
1. Mate-finding behavior of pine shoot beetles
Tomicus piniperda (female) on Scotch pine

2. Pheromones regulating competition and host colonization
Resin-covered pair of Dendroctonus brevicomis at entrance hole on ponderosa pine

3. Effect of mating on pheromone
Stridulatory organ of female Ips paraconfusus

4. Antiaphrodisiac in
male Lygus bugs

Antiaphrodisiac in male Lygus bugs renders females unattractive

Isolation of Semiochemicals:
1. Isolation of P. chalcographus aggregation pheromone
Pityogenes chalcographus on Norway spruce

2. Isolation of Ips duplicatus aggregation pheromone

3. Subtractive - Combination method
comparison of additive- and subtractive combinations of chemical fractions for bioassay

4. Heater Coils for Transfer Lines
heated transfer line softward

5. Canada Thistle

Bee species on Canada thistle flower in western Colorado

Dispersal and Host-Finding Models:
1. Searching for susceptible host trees
Norway spruce (Picea abies) forest, Värmland, Sweden

2. Dispersal out through rings of pheromone traps Program to use EAR in rings of traps to catch insects dispersing outward from center

3. Insect population control by pheromone traps

4. Effective Attraction Radius: EAR 12-m poles with cylindrical sticky traps for EAR

Orientation Behavior:
1. Odor-modulated anemotaxis and clumped arrival
portable fraction collector to monitor bark beetle arrival to pheromone

2. Orientation of bark beetles in a grid of pheromone traps
puddle trap catching bark beetles attracted to pheromone

3. Rotating windvane traps and upwind orientation

4. Interacting plumes
ponderosa pine forest near Oakhurst, California

5. Interspecific effects on attraction
Bioassay table (original) used in Berkeley, CA, for Ph.D. Thesis

6. Behavioral differences when flying or walking
A walking Pityogenes chalcographus (work on Pityogenes bidentatus)

Host Plant Chemistry and Semiochemicals:
1. Host tree chemistry affecting bark beetles
Conifers on campus of SLU-Alnarp, Sweden

2. Chemical Ecology of Bark Beetles

3. Plant galls and growth hormones induced by insects

4. Monoterpene diversity of ponderoda pine
ponderosa chemodiversity on Boulder mountain

5. Isoprenoid products of guayule rubber plants
Guayule latex rubber production plant

6. Lesquerella Oil-Seed Crops
Lesquerella fendleri field - Porapak Q odor collection of volatiles

Evolution and Chemical Structures:
1. Chalcogran and Methyl 2,4-Decadienoate
active enantiomer of chalcogran, a pheromone component of Pityogenes chalcographus

2. Constraints on Moth Pheromone Isomers
Java software to calculate number of moth pheromone isomers

3. Evolution of Communication Channels
Moth communication channels and speciation

4. Evolution of Host Selection and Insecticide Resistance
Gene frequencies of various alleles for detoxification and behavior

Release of Semiochemicals:
1. Diffusion - Dilution method

2. Piezoelectric Sprayer
Rotating funnel traps with plexiglass barrier above trap in foreground with piezoelectric sprayer

Models in Chemical Ecology:
1. Mating Disruption
and Mass Trapping

Java software to simulate mating disruption or mass trapping

2. Active Space versus EAR
Java software to simulate insect search and Effective Attraction Radius (EAR)

3. Flight layer
and EAR in 3D

Java software to simulate insect flight in 3D and EAR

4. Vertical Flight

Java software to simulate insect flight in 3D and EAR

5. Estimating Densities
of Flying Insects

Java software to simulate insect flight densities using EAR

6. Female or Male
Mass Trapping

Java software to simulate mass trapping of searching females (some other insects) or males (moths)

7. Dose-response curves
antennae / catch

Java software to simulate molecular fluxes and antennal saturation in dose-response curves

8. Pink bollworm and invasive species

Java software to simulate invasive species detection

Locust Semiochemicals:
1. Pheromones and chemical ecology of locusts

Trends in Chemical Ecology :
1. Computer analysis of trends in Chemical Ecology

2. Internet programs for drawing moth pheromone analogs
drawing moth analogs on Internet

Images © 1996-2013 by John A. Byers, Present address:

Research Supported by Grants to D.L. Wood, UC Berkeley (USDA, NSF); J. Löfqvist (NFR, SJFR), Lund Univ.; J.A. Byers (SJFR at Lund Univ. and SLU Alnarp); and USDA-ARS to Integrated Pest Management and Biological Control Unit of Arid-Land Agricultural Research Center, Maricopa, Arizona.