Mate choice confers direct benefits to females of Anastrepha fraterculus (Diptera: Tephritidae)

Abstract

Exposure to plant compounds and analogues of juvenile hormone (JH) increase male mating success in several species of tephritid fruit flies. Most of these species exhibit a lek mating system, characterized by active female choice. Although the pattern of enhanced male mating success is evident, few studies have investigated what benefits, if any, females gain via choice of exposed males in the lek mating system. In the South American fruit fly, Anastrepha fraterculus , females mate preferentially with males that were exposed to volatiles released by guava fruit or treated with methoprene (a JH analogue). Here, we tested the hypothesis that female choice confers direct fitness benefits in terms of fecundity and fertility. We first carried out mate choice experiments presenting females with males treated and non-treated with guava volatiles or, alternatively, treated and non-treated with methoprene. After we confirmed female preference for treated males, we compared the fecundity and fertility between females mated with treated males and non-treated ones. We found that A . fraterculus females that mated with males exposed to guava volatiles showed higher fecundity than females mated to non-exposed males. On the other hand, females that mated methoprene-treated males showed no evidence of direct benefits. Our findings represent the first evidence of a direct benefit associated to female preference for males that were exposed to host fruit odors in tephritid fruit flies. Differences between the two treatments are discussed in evolutionary and pest management terms.

Lemon and Schinus polygama essential oils enhance male mating success of Anastrepha fraterculus

“…This is in agreement with Vera et al (2013) for A. fraterculus and Flores et al (2011) for other Anastrepha species but contrasts with Bachman et al (2019), who found that copulations involving males exposed to guava volatiles lasted longer than those involving non‐exposed males. Although there is some controversy about the duration of copula as an indicator of male reproductive success in tephritid fruit flies, the evidence collected so far for A. fraterculus indicates that longer copulas correlate with lower tendency to remate and longer refractory period in the female (Abraham et al, 2011) and in higher fecundity (Bachmann et al, 2019). This high fecundity without remating would ensure high fitness to the male and, in the context of the SIT, may imply higher induced sterility in the wild population (Bachmann et al, 2019).…”

“…The essential oil from lemon largely consists of monoterpene hydrocarbons (91.9%), including limonene as the predominant compound (Ruiz et al, 2015), whereas the essential oil of S. polygama is composed mainly of monoterpene hydrocarbons and hydrocarbon sesquiterpenes with no single compound being predominant (Jofré‐Barud et al, 2014; Jofré‐Barud, 2018). Male enhancement in A. fraterculus was also achieved after exposure to guava volatiles (Vera et al, 2013; Bachmann et al, 2015, 2019), in which there is no predominant chemical group (Pino et al, 2001) and in an artificial mixture of seven compounds present in the guava volatiles, including limonene, in even proportions (Bachmann et al, 2015). Therefore, further studies are required in order to identify candidate compound(s) responsible of male enhancement.…”

“…Although there is some controversy about the duration of copula as an indicator of male reproductive success in tephritid fruit flies, the evidence collected so far for A. fraterculus indicates that longer copulas correlate with lower tendency to remate and longer refractory period in the female (Abraham et al, 2011) and in higher fecundity (Bachmann et al, 2019). This high fecundity without remating would ensure high fitness to the male and, in the context of the SIT, may imply higher induced sterility in the wild population (Bachmann et al, 2019).…”

“…This diet has been proven highly nutritious and a great boost to reproduction in females (Jaldo et al, 2001). Males were fed the same diet that we used in our previous studies focused on evaluating the role of fruit volatiles as male enhancers (Vera et al, 2013; Bachmann et al, 2015, 2019; Bachman, 2016), which consists of brewer’s yeast (Calsa; El Manantial, Tucumán, Argentina) and sugar (1:3 ratio). Flies were kept in separate rooms during the period of sexual maturation (10‐12 days) to avoid any effect of pheromone exposure before the mating test.…”

Symbionts do not affect the mating incompatibility between the Brazilian-1 and Peruvian morphotypes of the Anastrepha fraterculus cryptic species complex

“…However, an infected status may represent possible fitness costs, as the latency to mate decreased and the mating duration increased when flies were cured from Wolbachia . These characteristics have been proposed to be advantageous 43,44 . In the case of AfC, the absence of Wolbachia in both sexes correlates with a lower tendency to copulate, again suggesting a negative effect associated with the curing protocol.…”