Seasonal dynamics of: the pea aphid, Acyrthosiphon pisum (Harris), its natural enemies the seven spotted lady beetle Coccinella septempunctata Linnaeus and variegated lady beetle Hippodamia variegata Goeze, and their parasitoid Dinocampus coccinellae (Schrank)

Abstract

Abstract:Two important lady beetle species commonly found in alfalfa fields in Iran are the variegated lady beetle Hippodamia variegata Goeze and the seven spotted lady beetle Coccinella septempunctata (Linnaeus, 1758) (Coleoptera: Coccinellidae). These two species attack many aphid species including the pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae). In this study, the seasonal population changes of A. pisum, H. variegata, C. septempunctata and the parasitoid, Dinocampus coccinellae (Schrank) (Hymenoptera: Braconidae) were studied in alfalfa fields in the 2012 and 2013 seasonal periods. The highest ladybird densities were noted on July 5, 2012 and on September 6, 2013 (17.2±2.8 and 13.4±1.6) individuals per 20 sweeps, respectively. Parasitism rates by D. coccinellae ranged from approximately 3 to 6% in two subsequent years, respectively. Parasitism was higher early in the growing season. Most parasitised ladybirds were females. There was no significant relationship between the temperature and relative humidity with pea aphid populations, although the aphid populations declined during the hot summer period. In contrast, the relationship between temperature and the H. variegata population was significant and positive in both years of the study. It has been shown that these lady beetle species have a major role in reducing the pea aphid populations in alfalfa fields. Due to the relatively low percentage of field parasitism by D. coccinellae, this parasite might not reduce the biocontrol efficiency of lady beetle species.

Management of the major pests of french bean through development and validation of certain IPM modules, Assam, India

“…The use of predator of aphid and mite as one of the component of the module M II also leads to reduction of these pests. It has been shown that Coccinellid beetle have a major role in reducing the pea aphid populations in alfalfa fields that was conducted in Hamedan, Iran (Soleimani and Hossein, 2015). The findings of Jakhar and Chaudhary (2013) 2).…”

Functional response of Harmonia axyridis preying on Acyrthosiphon pisum nymphs: the effect of temperature

“…Many aphidophagous ladybird beetles (Coleoptera: Coccinellidae) are known to be exploited for conservative or augmentative release biocontrol programs of several economically important aphids in diverse crops, outdoors and in greenhouses 2 , suppressing aphid infestations below economically damaging levels 36 . Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is a generalist predator, is geographically wide-spread 37 , and has been extensively employed as a biocontrol agent of soft-bodied insects, including aphids in a diversity of crops 38 .…”

The Biology and Ecology of Parasitoid Wasps of Predatory Arthropods

“…Multivoltine parasitoid species, such as D. coccinellae, must synchronize their active period with that of their hosts (16), whose availability in turn depends on that of the host's prey. As a result of this and other factors, levels of parasitism may also vary over the course of a growing season (115,138,150). Host dissections showed that, in the field, parasitism rates of H. axyridis and Coleomegilla maculata, a native ladybird species in North America, were similar (67), but due to reduced host suitability, the rate of emergence of adult parasitoids from the former species is much lower (42).…”