Consumption of Cinara spp. (Hemiptera, Aphididae) by Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae)

Abstract

ABSTRACT. Adults and larvae of coccinellids were observed feeding on populations of the giant conifer aphids Cinara spp. on Pinus spp., in Southern Brazil. The objective of this research is to evaluate the consumption capacity of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) on these aphid species, in order to obtain information for biological control programs. Ten larvae of each predator species were fed with aphids of small size (nymphs of 1 st and 2 nd instars), and 10 with aphids of medium size (nymphs of 3 rd and 4 th instars), maintained under 15ºC, 20ºC and 25ºC, 12 h photophase and 70 + 10% relative humidity. The aphids were counted every 24 hours, replacing those that were consumed. The total consumption of Cinara by the larvae of C. sanguinea was not statistically different at the three temperatures: 325.5; 322.2 and 324.8 of small aphids and 121.3; 140.4 and 109.9 of medium ones, respectively at 15ºC, 20ºC and 25ºC. The consumption by H. convergens was higher than by C. sanguinea and increased noticeably with temperature: 444 aphids at 15ºC; 491.3 at 20ºC and 513.3 at 25ºC, considering the small aphids, and 187.1; 205.1 and 216.6 of medium aphids at the three temperatures. The small aphids weigh about half as much as medium ones and were preferred by all larval instars probably because they are easier to manipulate than the large ones. Both predators, especially the 4 th instar larvae, showed high consumption capacity on the Cinara nymphs at all temperatures and can be regarded as promising biological control agents.

Comparative demography of the exotic Harmonia axyridis with other aphidophagous coccinellids reared on artificial diet

“…Taking into account the number of viable eggs, H. convergens and C. sanguinea had similar results; and for the number of eggs per oviposition, H. convergens superseded C. sanguinea (Table 2). Cardoso & Lázzari (2003) observed that adults of C. sanguinea had longevity of 167.1 days when kept at 20 o C and, despite the difference in temperature, these results are close to the values of 147.0 (females) and 162.8 days (males) found in the present study.…”

“…Larval stage duration of H. convergens (11.02 days) was approximately the same as the results by Cardoso & Lázzari (2003) at 25 o C (10.9 days), and shorter than that reported by Kato et al (1999) (13.7 days). The duration of 4.48 days for the pupal period was similar to the 4.5 days obtained by Kato et al (1999), and shorter compared to the 6.3 days determined by Cardoso & Lázzari (2003), who added to this time the pre-pupal stage. Hippodamia convergens sex ratio (50%) was lower than the 60% proportion found by Kato et al (1999).…”

“…In the present study, egg-adult survival for C. sanguinea (42.0%) was lower than that described by Cardoso & Lázzari (2003) Regarding the mean longevity of adults, H. convergens appeared deficient in comparison with the other species, and no significant difference was observed between lifespan of females of C. sanguinea and H. axyridis (Table 2). However, for males, lifespan was longer in H. axyridis, followed by C. sanguinea and H. convergens.…”

“…Santa-Cecilia et al (2001) obtained a shorter time for pupal stage, 3.0 days for both sexes, in comparison to 3.77 days in the present study. Despite the small differences between the duration of each stage, the egg-adult time (17.40 days) was close to the 17.5 days found by Cardoso & Lázzari (2003) o C, 60-80% relative humidity, and 16:8-hour photophase, but less than the 3.4 days reported by Castro et al (2011), for H. axyridis feeding on Cinara atlantica (Wilson) (Hemiptera: Aphididae) at 25±1 o C, 70±10% relative humidity, and 12-hour photophase. The duration of the larval period of this species (9.38 days) was lesser than that reported by other authors: (2001) (4.9 to 6.0 days), but lesser than the 6.6 days reported by Lanzoni et al (2004), who added the pre-pupal period.…”

“…In the current study, the larval stage duration (9.26 days) was longer than those reported by Cardoso & Lázzari (2003) (8.6 days) and Santa-Cecilia et al (2001) (males 8.2 days, and females 8.5 days) for C. sanguinea feeding on Schizaphis graminum (Rondani) (Hemiptera: Aphididae) at 25 o C. In this species, a longer pupal period was observed by Cardoso & Lázzari (2003) (4.7 days), but the authors did not make reference to the pre-pupal period, which was probably included in this count. Santa-Cecilia et al (2001) obtained a shorter time for pupal stage, 3.0 days for both sexes, in comparison to 3.77 days in the present study.…”