Life table and predation rates of the syrphid fly Allograpta exotica, a control agent of the cowpea aphid Aphis craccivora

Abstract

Please cite this article as: Arcaya, E., Pérez-bañ ón, C., Mengual, X., zubcoff-vallejo, J.j., Rojo, S., Life table and predation rates of the syrphid fly Allograpta exotica, a control agent of the cowpea aphid Aphis craccivora, Biological Control (2017), doi: http://dx.doi.org/10. 1016/j.biocontrol.2017.09.009 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. The average recorded duration of A. exotica development was 2.0, 7.4 and 5.7 days for eggs, larvae and pupae respectively, and 15.04 days from egg to adult emergence. The adult longevity was not significantly sex dependent, but imagoes lived longer than in previous studies. The offspring sex ratio was favorable to males. The mortality and survival rate were recorded on a daily basis for all immature stages and adults. The age specific survival rate was determined and the highest mortality occurred in eggs followed by mortality in 1st and 2nd instar larva.Moreover, in the present study different levels of aphid densities 10, 30, 40, 50, 60, 70, 80 and 100 were used to calculate the functional response. Based on logistic regression analyses the three instar larvae and the whole larval stage (first to third instar) exhibited a type II functional response. Handling time was shortest for the third larval instar followed by second and first instars. Potential use of A. exotica in augmentative biological control is discussed.

Demography and population parameters of two species of eristaline flower flies (Diptera, Syrphidae, Eristalini)

“…In both species, the greatest life expectancy was found in the adult stage as a result of the considerable mortality found in the preadult stages and the adults being the longest‐living stage in their life cycles (Figure ). This mortality in the larval stage seems to be more critical in comparison with other dipterous species analysed with the same life table method, in which the greatest life expectancy is commonly found at the larval stage (Arcaya, Pérez‐Bañón, Mengual, Zubcoff‐Vallejo, & Rojo, ; Gabre, Adham, & Chi, ; Samayoa & Hwang, ). For the two species analysed in this study, life expectancy reached higher values in the case of E. aeneus at all stages of its life cycle (Figure ).…”

Dual ecosystem services of syrphid flies (Diptera: Syrphidae): pollinators and biological control agents

“…For a predator to be an active biological control agent, it should be suitable for the particular environment and be able to control its prey population size (thus limiting plant injury) . The functional response defines the voracity and rate at which predators attack prey; this is a decisive factor in predator–prey population dynamics . Factors such as temperature, competition, prey availability and syrphid developmental stage influence the functional response of syrphid larvae …”

“…Life stage and aphid density drive the voracity of aphidophagous syrphid larvae. In general, the third larval stage – third instar – is the most voracious . Larval voracity also increases with aphid density, which is a useful feature as it might allow syrphid larvae to match prey consumption rates to changes in aphid population density .…”

Development cycle of a potential biocontrol agent: the American hoverfly, Eupeodes americanus, and comparison with the commercial biocontrol agent Aphidoletes aphidimyza

“…This favors a faster control of the prey population in agrosystems (Amano & Chant, 1977). In E. americanus, it was shorter than several other predators used for aphid control such as the ladybeetles Hippodamia variegata (Goeze) (18.1 days) and Adalia bipunctata (L.) (21.3 days) at 23 °C on M. persicae (Lanzoni et al, 2004;Jalali et al, 2009), and the hoverfly E. balteatus (21.2 days) on A. gossypii (at 26.6 °C) (Hong & Hung, 2010), but remains comparable to that of Sphaerophoria scripta (L.) (16.3 days) on Aphis craccivora Koch (at 22 and 25 °C) and Allograpta exotica (Wiedemann) (15.0 days, at 25 °C) (Moetamedinia et al, 2004;Arcaya et al, 2017).…”