INVESTIGADORES
BUTELER micaela
artículos
Título:
Oviposition behavior of the wheat stem sawfly when encountering plants infested with cryptic conspecifics
Autor/es:
BUTELER, M.; D. K. WEAVER; PETERSON, R.K
Revista:
ENVIRONMENTAL ENTOMOLOGY
Editorial:
Entomological Society of America
Referencias:
Lugar: Lanham, MD; Año: 2009
ISSN:
0046-225X
Resumen:
Insect herbivores typically oviposit on the most suitable hosts, but choices can be
modulated by detection of potential competition among conspeciÞcs, especially when eggs are
deposited cryptically. Larvae of the wheat stem sawßy, Cephus cinctus Norton, developing within an
already infested stem, experience elevated risk because only one will survive because of cannibalism.
To increase our understanding of host selection when the choices made by females can lead to severe
intraspeciÞc competition, females were presented with either uninfested wheat plants or with plants
previously exposed to other females in laboratory choice tests. The oviposition behavior of this insect
was described by recording the behavioral sequences that lead to and follow the insertion of the
ovipositor in both previously infested and uninfested stems. No signiÞcant differences were found in
frequencies of speciÞc behaviors or behavioral transitions associated with oviposition. In choice tests,
there was no difference in the numbers of eggs laid in infested and uninfested plants. Taller plants
received more eggs, irrespective of infestation. Females neither preferred nor avoided previously
infested hosts. Other characteristics of the host, such as stem height, may be more important in
determining suitability for oviposition. These Þndings support the use of management tactics relying
on the manipulation of oviposition behavior, such as trap cropping. Given that there is no evidence
for response to previously infested hosts, the infested plants in a trap crop would remain as suitable
as they were when uninfested, which could also lead to an increase in mortality caused by intraspeciÞc
competition.Cephus cinctus Norton, developing within an
already infested stem, experience elevated risk because only one will survive because of cannibalism.
To increase our understanding of host selection when the choices made by females can lead to severe
intraspeciÞc competition, females were presented with either uninfested wheat plants or with plants
previously exposed to other females in laboratory choice tests. The oviposition behavior of this insect
was described by recording the behavioral sequences that lead to and follow the insertion of the
ovipositor in both previously infested and uninfested stems. No signiÞcant differences were found in
frequencies of speciÞc behaviors or behavioral transitions associated with oviposition. In choice tests,
there was no difference in the numbers of eggs laid in infested and uninfested plants. Taller plants
received more eggs, irrespective of infestation. Females neither preferred nor avoided previously
infested hosts. Other characteristics of the host, such as stem height, may be more important in
determining suitability for oviposition. These Þndings support the use of management tactics relying
on the manipulation of oviposition behavior, such as trap cropping. Given that there is no evidence
for response to previously infested hosts, the infested plants in a trap crop would remain as suitable
as they were when uninfested, which could also lead to an increase in mortality caused by intraspeciÞc
competition.