Association of MACE‐based insecticide resistance in Myzus persicae with reproductive rate, response to alarm pheromone and vulnerability to attack by Aphidius colemani

Abstract

Reproductive success and response to alarm pheromone, both potentially important components of fitness, were assessed using clones of Myzus persicae (Sulzer) to establish associations with insecticide resistance conferred by insensitive modified acetylcholinesterase (MACE). Both traits showed significant trends that were apparently related to this mechanism. MACE forms appeared to reproduce at slower rates than non-MACE forms expressing moderate (R1) levels of another resistance mechanism based on elevated carboxylesterase. However, MACE forms were more responsive to alarm pheromone than their non-MACE counterparts. The potential implications for parasitoid performance were tested using two clones showing clear differences in alarm response. The level of parasitism of M persicae by the parasitoid Aphidius colemani (Viereck) was significantly lower in MACE forms on pepper crops compared to non-MACE forms. In addition, the distribution of MACE and non-MACE forms differed on the pepper plants, with more MACE forms being found on the growing points. The presence of the parasitoid A colemani did not alter this change in distribution.

Insecticide Resistance Mechanisms in the Green Peach Aphid Myzus persicae (Hemiptera: Aphididae) II: Costs and Benefits

“…Pleiotropic effects of E4/FE4 gene duplication and kdr mutation on important behavioral traits have been reported for M. persicae , particularly in response to environmental signals such as presence of natural enemies (parasitoids) and low temperatures, which ultimately could lead to reduced fitness [58]–[63]. In addition, the MACE mutation appears to reduce the fitness of individuals that carry it [64]. However, the effect of this mutation by itself has not been clarified yet [65], [66].…”

The Molecular Genetics of Insecticide Resistance

“…Moreover, in highly resistant clones of Myzus, changes in DNA methylation were also shown to be able to switch off the high levels of E 4 production associated with highly duplicated E 4 -encoding genes, thereby presumably reducing the energetic cost of having to make a large amount of esterase in the absence of pesticide (Field et al 1989b). The idea that only carboxylesterase-associated gene duplication could cause resistance persisted until 1990 when both insensitive acetylcholinesterase and altered voltage-gated sodium channels (kdr) were also shown to be involved in resistance to organophosphorus/carbamates and pyrethroids, respectively (MartinezTorres et al 1999;Foster et al 2003). In fact, retrospective surveys of the three resistance mechanisms in the United Kingdom actually showed that their relative frequencies had in fact been changing over time (Field and Foster 2002), suggesting that some mechanisms may show increased levels of fitness (in the absence of pesticide) or efficacy (in the presence of pesticide) over others.…”

Spatial and temporal dynamics of Myzus persicae clones in fields and suction traps

“…Myzus persicae clones with high levels of esterase have maladaptive behaviour affecting their ability to overwinter ( Foster et al , 1996( Foster et al , , 1997 whereas clones with the kdr gene are known to be less responsive to alarm pheromones, which may affect their ability to respond to unfavourable conditions (e.g. over crowding, poor plant nutrition, predation and parasitism; Foster et al , 1999Foster et al , , 2003Foster et al , , 2005.…”