Trade‐off between mobility and fitness inCydia pomonellaL. (Lepidoptera: Tortricidae)

Abstract

Abstract. 1. The codling moth Cydia pomonella, one of the most important pest insects of apple fruit orchards worldwide, is regarded as a ‘sedentary’ insect, but the natural populations consist of both mobile and sedentary genotypes that display different dispersal capacity in the field. The current study investigated whether there is a fitness consequence of being mobile in this species by comparing two strains with contrasting levels of mobility obtained through bi‐directional selection. 2. Female moths of the sedentary strain were significantly larger, laid more eggs during their lifespan, and both male and female moths of this strain lived longer, when compared with the mobile strain. 3. The age‐specific fecundity of female moths from the sedentary strain was significantly greater, in particular between 3 and 5 days after emergence when the peaks of both oviposition and flight capacity occur, relative to the mobile moths, thereby leading to a greater reproductive function. 4. These differences resulted in different demographic parameters between the two strains. The sedentary strain had a significantly greater net reproductive rate (Ro) and a higher intrinsic rate of natural increase (rm), although the generation time (T) was similar, hence requiring a shorter time to double the population size, in comparison to the mobile strain. 5. This study provides empirical evidence for the cost of being mobile in C. pomonella. Trade‐offs between mobility and fitness might have contributed to the existence of genetic variance for dispersal behaviour in the natural populations and the maintenance of relative sedentariness in the species.

Body mass and wing geometric morphology of the codling moth (Lepidoptera: Tortricidae) according to sex, location and host plant in the region of Maule, Chile

“…Our results support previous reports of sexual dimorphism in body mass and wing morphology in the codling moth (Schumacher et al, 1997a;Gu et al, 2006), with females showing larger thorax, abdomen and body mass than males. Larger body size is related to higher detoxification capacity, which confers resistance towards insecticides (Reyes et al, 2004(Reyes et al, , 2015Fuentes-Contreras et al, 2007).…”

“…However, no major differences in flight capacity between males and females were found in another study (Schumacher et al, 1997b). Flight activity was related with the circadian rhythm, age and mating status rather than sex (Schumacher et al, 1997b;Keil et al, 2001;Gu et al, 2006). Additionally, flight activity was higher in mated than virgin females and increased during the egg-laying period; therefore, little dispersal occurs before mating (Schumacher et al, 1997b).…”

“…Body size has also been related to dispersal capability in the codling moth: in the same population, larger females tend to be more fecund, live longer, and disperse less than smaller females (Gu et al, 2006). Flight distance was also negatively correlated with body weight and wing size in the codling moth, suggesting a trade-off between fitness and dispersal for this species (Schumacher et al, 1997a).…”

Relationship of flight and reproduction in beet armyworm, Spodoptera exigua (Lepidoptera: Noctuidae), a migrant lacking the oogenesis-flight syndrome

“…It would extend the option for individuals to escape unfavorable conditions and to exploit new habitat across a wide temporal window (Southwood, 1962;Lidicker and Caldwell, 1982;Rankin and Singer, 1984). Unlike migratory insects exhibiting the oogenesis-flight syndrome (Rankin et al, , 1994Colvin and Gatehouse, 1993;Keil et al, 2001;Gu et al, 2006;Lorenz, 2007), we hypothesize that S. exigua pursues multiple matings during the migratory phase and that it oviposits part of its eggs en route. Supporting this is that mating frequency and the numbers of eggs laid up to 7 days post-eclosion have no negative influence on flight performance, which is consistent with synchronous migratory behavior.…”

“…The cost is usually manifested, especially in wing dimorphic species, as decreased reproductive output caused by a prolonged pre-oviposition period, decreased longevity, and decreased lifetime egg production (Dingle and Arora, 1973;Walters and Dixon, 1983;Roff, 1984;Zera, 1984;Zera and Mole, 1994). Physiological management of the migration-reproduction trade-off often includes a package of adaptations referred to as the oogenesis-flight syndrome, which was taken for many years as a fundamental trait of insect migrants (Johnson, 1969;Rankin et al, 1986Rankin et al, , 1994Colvin and Gatehouse, 1993;Keil et al, 2001;Gu et al, 2006;Lorenz, 2007). The syndrome describes a pattern in which the flight apparatus develops soon after eclosion to support migratory flight, migratory flight is initiated during the adult prereproductive stage when ovarian development and mating behavior are suppressed, and females switch to egg development and oviposition activity rapidly after termination of migration.…”