Responses of an Aphidophagous Ladybird Beetle,AnegleisCardoni, to Varying Densities ofAphis gossypii

Abstract

Laboratory experiments were conducted to determine the functional and numerical responses of fourth instar larvae, adult male, and adult female ladybird beetles, Anegleis cardoni Weise (Coleoptera: Coccinellidae), to different densities of aphids, Aphis gossypii Glover (Hemiptera: Aphididae), on the bottle gourd, Lagenaria vulgaris Seringe (Cucurbitales: Cucurbitaceae). The results revealed a density dependent, Type II functional response of A. cardoni. Prey consumption increased curvilinearly with an increase in prey density for all three predatory stages. Numerical responses revealed significant increases in oviposition with increases in prey density. The food exploitation efficiency and the efficiency of conversion of ingested food decreased with increases in prey density. The attack rate was highest for adult females, followed by fourth instar larvae and adult males. Prey consumption was highest and handling time lowest in fourth instar larvae, followed by adult females and males. Therefore, fourth instar larvae of A. cardoni may be considered the most efficient predatory stage in aphid management strategies.

Feeding Efficiency of Six Beetle Species against Mustard Aphid, Lipaphis erysimi (Kalt.) in Uttarakhand

“…Similar findings were also reported by Omkar and Kumar (2013) in the management strategies of A. cordoni against mustard aphid. Omkar et al, (2009) further reported that the performance of A. cardoni was preydependent and the order of suitability of the prey tested was A. gossypii > A. craccivora > L. erysimi.…”

Functional response and predatory interactions in conspecific and heterospecific combinations of two congeneric species (Coleoptera: Coccinellidae)

“…In the present study, negative linear coefficients (P 1 ) for conspecific and heterospecific groups of two females reveal that the rate of consumption of prey by these predators decreases with increase in abundance of prey, which indicate a Type II functional response (Bayoumy, 2011a, b;Osman & Bayoumy, 2011;Omkar & Kumar, 2013). The curves of the proportions of prey consumed by C7 + C7, Ct + Ct and C7 + Ct pairs of females are similar and appear to take the form of a decelerating type II functional response when provided with a low to optimal supply of prey, followed by an accelerating type III functional response when provided with an optimal to abundant supply of prey.…”

“…a sigmoidal functional response (e.g., Sarmento et al, 2007;Abdollahi et al, 2010;Bayoumy, 2011a). Several studies have evaluated the functional responses of particular species of lady beetles (Sarmento et al, 2007;Abdollahi et al, 2010;Bayoumy, 2011a;Osman & Bayoumy, 2011;Gupta et al, 2012;Omkar & Kumar, 2013) and the nature of their predator-predator interactions (synergistic /additive /antagonistic) within aphidophagous guilds (Losey & Denno, 1998, 1999Snyder & Ives, 2003;Costamagna et al, 2007;Snyder, 2009;Grez et al, 2007Grez et al, , 2011Grez et al, , 2012. However, studies of the functional response of species within predatory guilds (Omkar & Pervez, 2011;Jamour & Shishehbor, 2012;Vanacloacha et al, 2013) coupled with that of the interaction between predators are scanty (Snyder & Ives, 2003;Omkar & Pervez, 2011).…”

“…One of the most informative ways of studying predatorprey interactions is to measure the functional response of a predator to prey abundance, which can be used as a measure of searching efficiency and is often correlated with its biocontrol efficiency (Fathipour et al, 2006;Bayoumy, 2011a, b;Bayoumy & Michaud, 2012;Omkar & Kumar, 2013). There are five types of functional responses, viz.…”

“…Several studies on different species of lady beetles, however, reveal that in lady beetles the type II functional response predominates (e.g., Omkar & Pervez, 2011;Osman & Bayoumy, 2011;Gupta et al, 2012). It is characterized by a curvilinear increase in predation with increase in prey density, becoming asymptotic at high prey densities and thereafter remaining constant due to satiation (Mills, 1982;Jalali et al, 2010) and is not stage specific (Omkar & Srivastava, 2001;Omkar & Kumar, 2013). However, some studies also report type III of reproductive diapause in males, pre-hibernation mating, storage of sperm by females during winter and ecological plasticity in terms of both genetic and phenotypic polymorphism (Hodek & Michaud, 2008).…”