scholarly journals Efficacy of Botanical Insecticides against the Pea Aphid, Acyrthosiphon pisum (Harris) and Effect on Some of Its Natural Enemies on Field Pea in South Central Ethiopia

2016 ◽  
Vol 4 (2) ◽  
pp. 53 ◽  
Author(s):  
Lemmessa Gemmeda ◽  
Gashawbeza Ayalew
2005 ◽  
Vol 95 (2) ◽  
pp. 125-131 ◽  
Author(s):  
G. Kunert ◽  
W.W. Weisser

AbstractThe pea aphidAcyrthosiphon pisumHarris has been shown to produce an increasing proportion of winged morphs among its offspring when exposed to natural enemies, in particular hoverfly larvae, lacewing larvae, adult and larval ladybirds and aphidiid parasitoids. While these results suggest that wing induction in the presence of predators and parasitoids is a general response of the pea aphid, the cues and mechanisms underlying this response are still unclear. Tactile stimuli and the perception of chemical signals as well as visual signals are candidates for suitable cues in the presence of natural enemies. In this paper the hypothesis that the aphids' antennae are crucial for the wing induction in the presence of natural enemies is tested. Antennae of pea aphids were ablated and morph production was scored when aphids were reared either in the presence or the absence of predatory lacewing larvae over a six-day period. Ablation of antennae resulted in a drastic drop in the proportion of winged morphs among the offspring, both in the presence and the absence of a predator whereas predator presence increased wing induction in aphids with intact antennae, as reported in previous experiments. The results show that antennae are necessary for wing induction in the presence of natural enemies. Critical re-examination of early work on the importance of aphid antennae and tactile stimuli for wing induction suggests that a combination of tactile and chemical cues is likely to be involved not only in predator-induced wing formation but also for wing induction in response to factors such as crowding in the aphid colony.


2002 ◽  
Vol 92 (4) ◽  
pp. 351-357 ◽  
Author(s):  
D.A. Stacey ◽  
M.D.E. Fellowes

AbstractThe ability to resist or avoid natural enemy attack is a critically important insect life history trait, yet little is understood of how these traits may be affected by temperature. This study investigated how different genotypes of the pea aphidAcyrthosiphon pisumHarris, a pest of leguminous crops, varied in resistance to three different natural enemies (a fungal pathogen, two species of parasitoid wasp and a coccinellid beetle), and whether expression of resistance was influenced by temperature. Substantial clonal variation in resistance to the three natural enemies was found. Temperature influenced the number of aphids succumbing to the fungal pathogenErynia neoaphidisRemaudière & Hennebert, with resistance increasing at higher temperatures (18 vs. 28°C). A temperature difference of 5°C (18 vs. 23°C) did not affect the ability ofA. pisumto resist attack by the parasitoidsAphidius erviHaliday andA. eadyiStarý, González & Hall. Escape behaviour from foraging coccinellid beetles (Hippodamia convergensGuerin-Meneville) was not directly influenced by aphid clone or temperature (16 vs. 21°C). However, there were significant interactions between clone and temperature (while most clones did not respond to temperature, one was less likely to escape at 16°C), and between aphid clone and ladybird presence (some clones showed greater changes in escape behaviour in response to the presence of foraging coccinellids than others). Therefore, while larger temperature differences may alter interactions betweenAcyrthosiphon pisumand an entomopathogen, there is little evidence to suggest that smaller changes in temperature will alter pea aphid–natural enemy interactions.


1987 ◽  
Vol 119 (11) ◽  
pp. 1055-1057 ◽  
Author(s):  
R.L. Thiboldeaux ◽  
W.D. Hutchison ◽  
D.B. Hogg

The pea aphid, Acyrthosiphon pisum (Harris), is an important pest of alfalfa, Medicago sativa L., in Wisconsin because of its characteristic potential for exponential population growth (Hutchison and Hogg 1984, 1985) and the subsequent damage in both hay quality and quantity inflicted by high populations (Cuperus et al. 1982). In Wisconsin, as in most alfalfa-producing states, there is a vast complex of natural enemies (Hutchison and Hogg 1985) that influence pea aphid population dynamics, including the hymenopteran primary parasitoids from the Aphidiidae. These primary species, however, are also attacked by several secondary parasitoids from the families Megaspilidae, Pteromalidae, and Alloxystidae.


2005 ◽  
Vol 83 (8) ◽  
pp. 1138-1141 ◽  
Author(s):  
Joshua O Podjasek ◽  
Lisa M Bosnjak ◽  
Daniel J Brooker ◽  
Edward B Mondor

In response to increased predation risk, many organisms exhibit transgenerational polyphenisms whereby offspring have behavioural and (or) morphological adaptations to avoid natural enemies. The mechanisms underlying altered phenotypic expression, however, are not well understood. Aphids commonly exhibit a transgenerational wing-induction polyphenism in response to predators and parasitoids, but the stimuli inducing winged offspring production have not yet been identified. As aphids commonly emit the alarm pheromone (E)-β-farnesene (EBF) when physically attacked, this compound is a reliable signal of increased predation risk for asexual conspecifics. Here we show that maternal detection of EBF induces a transgenerational wing polyphenism in offspring of the pea aphid, Acyrthosiphon pisum (Harris, 1776). In response to 50, 500, or 5000 ng of EBF vapor, aphids responded with 2.5-, 5.0-, and 6.0-fold increases in winged offspring production, respectively. Thus, alarm pheromone may alter aphid transgenerational phenotypic expression, thereby influencing aphid – natural enemy dynamics.


2007 ◽  
Vol 98 (1) ◽  
pp. 59-62 ◽  
Author(s):  
G. Kunert ◽  
K. Schmoock-Ortlepp ◽  
U. Reissmann ◽  
S. Creutzburg ◽  
W.W. Weisser

AbstractPrevious studies have shown that the aphid species, Aphis fabae Scopoli and Megoura viciae Buckton, do not produce winged offspring in the presence of natural enemies, in contrast to results for the pea aphid (Acyrthosiphon pisum (Harris)) and the cotton aphid (Aphis gossypii Glover); but these studies did not involve exposing aphids directly to natural enemies. We exposed colonies of both A. fabae and M. viciae to foraging lacewing (Chrysoperla carnea (Stephens)) larvae and found that the predators did not induce winged morphs among offspring compared to unexposed controls. Colonies of A. fabae responded to an increase in aphid density with increasing winged morph production, while such response was not found for M. viciae. We suggest that different aphid species differ in their susceptibility to natural enemy attack, as well as in their sensitivity to contact.


1990 ◽  
Vol 122 (6) ◽  
pp. 1193-1199 ◽  
Author(s):  
J.J. Soroka ◽  
P.A. Mackay

AbstractA comparison of the effects of infestation by known numbers of pea aphids, Acyrthosiphon pisum (Harris), on six field pea cultivars was made in field cage tests. The largest population of aphids developed on the cultivar Trapper and the smallest on the cultivar Century, with differences in aphid numbers between these cultivars significant for mature plants. Infested plants of Trapper had a significantly lower number of pods per plant, and infested plants of all cultivars had decreased seed weights, both per metre row and of 250 seeds, when compared with control plants. In all cultivars except Trapper, the most severely affected yield component was weight of 250 seeds.


2012 ◽  
Vol 86 (2) ◽  
pp. 235-244 ◽  
Author(s):  
Cory S. Straub ◽  
Nathan P. Simasek ◽  
Mark R. Gapinski ◽  
Regan Dohm ◽  
Ellen O. Aikens ◽  
...  

2013 ◽  
Vol 80 (2) ◽  
pp. 525-533 ◽  
Author(s):  
Tsutomu Tsuchida ◽  
Ryuichi Koga ◽  
Akiko Fujiwara ◽  
Takema Fukatsu

ABSTRACTA gammaproteobacterial facultative symbiont of the genusRickettsiellawas recently identified in the pea aphid,Acyrthosiphon pisum. Infection with this symbiont altered the color of the aphid body from red to green, potentially affecting the host's ecological characteristics, such as attractiveness to different natural enemies. In European populations ofA. pisum, the majority ofRickettsiella-infected aphids also harbor another facultative symbiont, of the genusHamiltonella. We investigated thisRickettsiellasymbiont for its interactions with the coinfectingHamiltonellasymbiont, its phenotypic effects onA. pisumwith and withoutHamiltonellacoinfection, and its infection prevalence inA. pisumpopulations. Histological analyses revealed that coinfectingRickettsiellaandHamiltonellaexhibited overlapping localizations in secondary bacteriocytes, sheath cells, and hemolymph, whileRickettsiella-specific localization was found in oenocytes.Rickettsiellainfections consistently altered hosts' body color from red to green, where the greenish hue was affected by both host and symbiont genotypes.Rickettsiella-Hamiltonellacoinfections also changed red aphids to green; this greenish hue tended to be enhanced byHamiltonellacoinfection. With different host genotypes,Rickettsiellainfection exhibited either weakly beneficial or nearly neutral effects on host fitness, whereasHamiltonellainfection andRickettsiella-Hamiltonellacoinfection had negative effects. Despite considerable frequencies ofRickettsiellainfection in European and North AmericanA. pisumpopulations, noRickettsiellainfection was detected among 1,093 insects collected from 14 sites in Japan. On the basis of these results, we discuss possible mechanisms for the interaction ofRickettsiellawith other facultative symbionts, their effects on their hosts' phenotypes, and their persistence in natural host populations. We propose the designation “CandidatusRickettsiella viridis” for the symbiont.


Sign in / Sign up

Export Citation Format

Share Document