The impact of insecticide resistance in the currant‐lettuce aphid, Nasonovia ribisnigri, on pest management in lettuce

Abstract

1 This paper reports on experiments to determine how two different insecticide resistance phenotypes in the aphid Nasonovia ribisnigri (Mosley), which is a major pest of lettuce, change its susceptibility to pyrethroid insecticides and the carbamate pirimicarb. 2 A novel statistical approach determined how the effectiveness of different insecticides was changed by the two resistance phenotypes. This compared the between-plant distribution of aphid numbers, as opposed to the mean number of aphids per plant. 3 Results from field cage experiments showed that the effect of the resistances differed. Pyrethroid resistance resulted in lower mortality immediately after application of pyrethroids, whereas resistance to pirimicarb shortened the time over which the chemical was effective. 4 The results of laboratory bioassays suggested that these two resistances were not found together in N. ribisnigri. However, the results reported here contradict this assertion. 5 Experiments with insecticide residues showed that reproduction of resistant N. ribisnigri was greater than that of susceptible N. ribisnigri on plants with ageing insecticide residues, even in circumstances where mortality of resistant and susceptible clones of N. ribisnigri were similar. 6 If more than a few aphids are found on a plant then a whole consignment can be rejected for processing. The results reported here suggest that the effect of both insecticide resistances in N. ribsinigri will be to increase the proportion of lettuce heads with an unacceptable number of aphids on them, leading to increased rejection of plants for processing.

The effects of a plant defence priming compound, β-aminobutyric acid, on multitrophic interactions with an insect herbivore and a hymenopterous parasitoid

“…Control of aphids, particularly in a field crop situation, is still largely performed with the use of contact and systemic chemical insecticides (Dewar 2007). However, the need to develop more environmentally sustainable agricultural practices, along with the rising number of cases of insect resistance, have led to an increasing awareness of the need to reduce, or integrate, the use of conventional biocides (Kift et al 2004;Parker et al 2006). Two alternative forms of crop protection that are much discussed are the application of chemical compounds that enhance the plant's natural defences and the use of arthropod antagonists as biocontrol agents.…”

Effects of prey species and its density on larval performance of two species of hoverfly larvae, Episyrphus balteatus de Geer and Eupeodes corollae Fabricius (Diptera: Syrphidae)

“…Aphids are one of the most devastating insect pests for many agricultural crops and fruits due to the characteristic sucking of plant phloem sap and transmission of plant viruses (Power, 1987;Werker et al, 1998;Dusi and Peters, 1999;Elibuyuk, 2003;Fiebig et al, 2004;Rassaby et al, 2004), and they easily develop insecticide resistance (Herron et al, 2001;Kift et al, 2004). Nowadays, environmental hazards due to regular and rather intensive chemical insecticide spraying is a growing concern.…”

The activity of a selected extract of Drimys winteri bark and polygodial on settling and probing behavior of the lettuce aphid Nasonovia ribisnigri

“…As a result, the percentage of marketable lettuce heads decreases, causing great financial losses for lettuce growers. Insecticide applications is the most common strategy to control the lettuce aphid, but the insecticide effectiveness is often limited because this aphid species has developed resistance to many registered insecticides (Kift et al 2004;Rufingier et al 1997). Cultivars of aphid-resistant lettuce have also been developed, but it is not clear if this resistance will persist over time (van der Arend 2003).…”