Life table and demographic parameters of the coccinellid predatory species, Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) when fed on two aphid species

Abstract

The study aimed to determine the effect of two aphid species; Lipaphis erysimi (Kaltenbach) and Aphis gossypii Glover (Hemiptera: Aphididae) on life table and demographic parameters of Hippodamia convergens Gu`erin-M´eneville (Coleoptera: Coccinellidae). The developmental period of all life stages of H. convergens was shorter when fed on L. erysimi. Net reproductive rate (Ro) was higher (159.85 offspring/individual) on L. erysimi, while it was 87.85 offspring/individual on A. gossypii. Mean generation time (T) was shorter (30.49 d) on L. erysimi than on A. gossypii (45.1 days). Values of the intrinsic rate of increase (r) and finite rate of increase (λ) were calculated as 0.166 days−1 and 1.181 days−1, respectively, on L. erysimi that were higher than on A. gossypii (0.099 days−1 and 1.104 days−1, respectively). Similarly, the survival rate was also higher when the predator was fed on L. erysimi. Overall, the findings suggest using L. erysimi as a better source of prey than A. gossypii for rearing H. convergens.

Life tables of the ladybird beetles Harmonia axyridis, Cycloneda sanguinea and Hippodamia convergens reared on the greenbug Schizaphis graminum

“…The instantaneous rate of population increase (r m ) refers to the maximum population growth rate under optimal space, food, and intraspecific influence, and is considered the most useful life table parameter for comparing the growth rates of different populations (Price, 1984). The r m values found for C. sanguinea, H. convergens, and H. axyridis in this study are higher than those reported in previous studies (Lanzoni et al, 2004;Milléo et al, 2014;Zazycki et al, 2015;Arshad et al, 2020). The high values of r m shown by these coccinellids here demonstrated that S. graminum is a suitable essential prey for them (Hodek and Evans, 2012).…”

“…Female coccinellids tend to disperse as a strategy to disperse their eggs widely in the area where they live (Evans, 2003). Although the dynamics of searching behavior of coccinellids is not sufficiently understood (Pervez and Yadav, 2018), the present findings indicated that the almost constant reproductive activity that continues through the entire In comparison to the fecundity values found for the coccinellids in the current study, Arshad et al (2020) reported lower values for H. convergens fed on the aphids Aphis gossypii Glover (251.0 eggs per female) and Lipaphis erysimi (Kalt.) (319.7 eggs per female) (Hemiptera: Aphididae).…”

“…The net replacement rate (R 0 ) and the population doubling time (DT) of C. sanguinea, H. axyridis, and H. convergens differed from those in earlier studies (Abdel-Salam and Abdel-Baky, 2001;Lanzoni et al, 2004;Milléo et al, 2014;Arshad et al, 2020). Milléo et al (2014), using a diet consisting of E. kuehniella eggs, found higher R 0 values for H. axyridis (2226.89 female offspring), C. sanguinea (499.0 female offspring), and H. convergens (450.15 female offspring) than the values found in this study.…”

“…R 0 values for H. convergens differed significantly when the species was reared on L. erysimi (R 0 = 159.85 female offspring) and A. gossypii (R 0 = 87.85 female offspring) (Arshad et al, 2020). In addition to fecundity, other biological traits of coccinellids such as survival, longevity, and consequently life table parameters can be affected by the quality and quantity of food (Hodek and Evans, 2012;Nedvěd and Honěk, 2012;Arshad et al, 2020). These potentially influencing factors help to clarify the differences in the values for net replacement rate (R 0 ) and population doubling time (DT) observed in the above-mentioned studies.…”

“…Castro-Guedes et al ( 2016) reported a similar DT, but a significantly higher R 0 for H. axyridis reared on Brevicoryne brassicae (L., 1758) (R 0 = 320.5 female offspring) and Cinara atlantica (Wilson, 1919) (R 0 = 373.77 female offspring) (Hemiptera: Aphididae) than on frozen eggs of E. kuehniella (R 0 = 277.43 female offspring). R 0 values for H. convergens differed significantly when the species was reared on L. erysimi (R 0 = 159.85 female offspring) and A. gossypii (R 0 = 87.85 female offspring) (Arshad et al, 2020). In addition to fecundity, other biological traits of coccinellids such as survival, longevity, and consequently life table parameters can be affected by the quality and quantity of food (Hodek and Evans, 2012;Nedvěd and Honěk, 2012;Arshad et al, 2020).…”