Delayed mating and reproduction in the autumn gum moth Mnesampela privata

Abstract

1 The success of mating disruption using synthetic sex pheromones depends not only on preventing mating, but also on delaying mating in the target insect. Using the geometrid pest of Eucalyptus plantations, Mnesampela privata (Guenée), we determined the effect of delaying mating when imposed on males only, females only or on both sexes simultaneously, for 1, 3, 5 and 7 days. 2 Delayed mating had a significant negative impact on reproduction, with a 0.89-fold decrease in the likelihood of mating and a 0.67-fold decrease in the likelihood of that mating resulting in fertile eggs for every day that mating is delayed. A mating delay of 7 days reduced the mean number of viable eggs laid to 4-13% of that laid by moths paired immediately after emergence. 3 Male only imposed mating delays had a significantly lower effect on reducing the likelihood of pairs mating than when both sexes were delayed. A delay imposed on one sex only or on both sexes simultaneously, however, had a similar negative impact on the proportion of fertile matings as well as on the total number of fertile eggs laid. 4 Longevity of mated female and male M. privata was significantly different between mating delay treatments, with a significant decline in female longevity when they mated with older males. 5 The underlying mechanisms causing a decline in female reproductive output when a mating delay was imposed on males versus females are discussed in relation to the reproductive biology of M. privata and the potential of using mating disruption strategies to control populations in Eucalyptus plantations.

Managing the white grub beetle Dasylepida ishigakiensis (Coleoptera: Scarabaeidae) in sugarcane fields on Miyako Island, Japan, using sex attractant pheromone: effects of mating delay on the reproductive ability of laboratory-reared and field-collected females

“…Mating success -defined as the proportion of females that produced progeny relative to the number that were mated -was negatively affected when mating occurred relatively late in adulthood. Furthermore, consistent patterns were observed for several other parameters, including the number of eggs laid, number of eggs that produced progeny and hatchability, consistent with reports from lepidopteran species (Kiritani and Kanoh, 1984;Henneberry and Clayton, 1985;Wakamura et al, 1989;Rogers and Marti, 1994;Wakamura and Takai, 1995;Torres-Vila et al, 2002;Huang and Subramanyam, 2003;Michereff et al, 2004;Jiao et al, 2006;Walker and Allen, 2011). On the other hand, lifespan and the time between mating and oviposition were not greatly affected by mating delay.…”

“…1). Other factors potentially responsible for the age-dependent reductions in mating ability and fertility may include the reduced production of sex pheromones, cessation of calling behaviour, reduced female receptivity to mating, loss of egg viability and increases in oocyte degradation products that can interfere with sperm migration and fertilization, as has been observed in other insect species (Torres-Vila et al, 2002;Stelinski and Gut, 2009;Walker and Allen, 2011). In D. ishigakiensis species, female adults change the concentration and chemical make-up of their pheromones as they age Fujiwara-Tsujii et al, 2012).…”

Effect of Increased Male and Female Age at Mating on the Reproductive Performance of <I>Cnaphalocrocis medinalis</I> (Crambidae: Lepidoptera)

“…medinalis male treatment has also been shown to have a signiÞcant negative impact on egg number and hatchability of females over the lifespan, as has been reported in P. interpunctella (Huang and Subramanyam 2003), C. jactatana (Jimé nez-Pé rez and Wang 2003), Leucoptera coffeella (Gué rin-Mé neville) (Michereff et al 2004), and M. privata (Walker and Allen 2011). In these species, the effect of male mating delay on reproduction is less than that of females.…”

“…has been reported in Plodia interpunctella (Hü bner) (Huang and Subramanyam 2003) and Mnesampela privata (Guené e) (Walker and Allen 2011). The amount of sex pheromones in the glands of virgin C. medinalis females increased gradually after age 2, reached a maximum at age 4, and then decreased (Kawazu and Tatsuki 2002).…”

“…Such studies could not compare whether one sex was more severely affected by delayed mating. Only four previous studies on delayed mating in insects have directly compared the effect of delayed mating imposed on males or females with that on both sexes simultaneously (Huang and Subramanyam 2003, Jimé nez-Pé rez and Wang 2003, Stelinski and Gut 2009, Walker and Allen 2011. Only two studies on Cnephasia jactatana Walker (Jimé nez-Pé rez and Wang 2003), Argyrotaenia velutinana (Walker), and Pandemis pyrusana Kearfott (Stelinski and Gut 2009) have shown an additive decrease in female reproductive performance, when ages of both sexes at mating were simultaneously increased.…”