DOI: 10.5061/dryad.q573n5tq3
title: Data from: Fecundity of diamondback moth females when offered honey with pyridalyl, a selective insecticide

description: We previously reported that the presence of pyridalyl, a selective
 insecticide, in aqueous honey  (50 % v/v) negatively affects the
 survival of diamondback moth (Plutella xylostella: DBM) adults. However,
 it remains unclear whether toxicity of pyridalyl in aqueous honey affects
 the fecundity of adult female DBMs. We analyzed the survival and fecundity
 of adult DBM under the water, honey, or honey + pyridalyl conditions in
 glass tubes containing Japanese mustard spinach (Brassica rapa: Komatsuna)
 leaves for 10 days. The survival of adults under the honey (50 % v/v) and
 honey + pyridalyl (100-fold dilution) conditions was significantly higher
 and lower, respectively, than under the water condition during the
 experimental period. The number of eggs laid by DBM females each day
 (fecundity) under the water condition was significantly lower than that
 under the honey condition throughout the experimental period, except on
 day 1. In contrast, the numbers under the water, and honey + pyridalyl
 conditions were not significantly different, except on day 2 (the honey +
 pyridalyl condition was significantly lower). To study the effects of
 plants grown in pots on the survival and fecundity of DBM females, we
 conducted experiments using acrylic cages containing potted komatsuna
 plants. The survival trends under the honey, and honey + pyridalyl
 conditions in the cages were similar to those in the glass tubes.
 Fecundity was evaluated based on the total number of subsequent
 generations (DBM larvae and pupae) on day 10. The numbers were
 significantly higher in the honey condition than in the water condition.
 In contrast, the number in the honey + pyridalyl condition was not
 significantly different from that in the water condition. Based on these
 findings, the possible use of pyridalyl in honey for the biological
 control of DBM is discussed.
description: <strong>Food sources
 </strong> A
 commercial formulation of pyridalyl (Pleo<sup>®</sup>
 flowable: pyridalyl 10 % in water; Sumitomo Chemical Company Limited,
 Osaka, Japan) was used as the selective insecticide. A 100-fold dilution
 of pyridalyl in aqueous honey solution was selected as the test food
 source (see Introduction). An aqueous honey solution (50 % v/v) was
 provided to DBM adults as a positive control food source. As a negative
 control, we offered a non-sugary food source (water only) to DBM
 adults. <strong>Experiments</strong> Experiments were conducted in glass tubes and acrylic cages. Glass tube experiments were designed to isolate and examine the effects of pyridalyl on honey. Acrylic cage experiments were structured to evaluate how the combination of plants and pyridalyl in honey affected the performance of DBM adults.   <em>Glass tube experiment.</em><strong><em> </em></strong>The effects of different food sources on the survival and number of eggs laid by DBM females were observed in a glass tube (1.8 cm diameter; length: 12 cm) containing a piece of komatsuna leaf (1 cm × 3 cm) as an oviposition substrate (Uefune et al. 2016). A piece of cotton wool (1 cm × 1 cm) impregnated with 500 mL of either honey or honey plus pyridalyl was placed in a tube. For the non-sugary food condition, a piece of moist cotton wool (1 cm × 1 cm) was placed near the tube opening. One female and one male were introduced into each tube. When females did not deposit eggs on the day following the commencement of the experiment (i.e., mating did not occur in the tube on the first day), the experiment was terminated.  The number of eggs laid on the leaf pieces and the surface of the glass tube were counted daily. The glass tubes were renewed daily using cotton wool and leaf pieces. We repeated the experiments 18 times for honey, and non-sugary food conditions and 17 times for the honey + pyridalyl condition by using different males and females in the climate-controlled room (25 ± 3 °C, 50 ± 10 % relative humidity) for 10 days.<strong> </strong> <em>Acrylic cage experiment.</em> The effects of the food source on the survival and number of the next generation (larvae and pupae) were also determined in an acrylic cage (60 cm × 60 cm × 60 cm) equipped with two windows (25 cm × 25 cm) covered with nylon gauze on opposite sides and a 30 cm × 30 cm sliding door at the front, set in the climate-controlled room. Nine potted komatsuna plants were placed in cages (3 × 3 formations) to study the effects of plants grown in soil on the survival and fecundity of DBM females. To water the plants, a komatsuna pot was placed in a plastic cup (upper diameter: 12 cm, lower diameter: 9.5 cm, depth: 6 cm) filled with water. Three experimental conditions were examined: water only, honey, and honey + pyridalyl. Two food-feeding devices (either dish or bottle devices; see section below) were placed in the cage separately near the meshed windows in a symmetrical position. Three females and six males were released. The food-feeding devices were replaced with new ones three and six days after release. Observations were conducted 3, 6, and 10 d after the start of the experiment. On day-3 and day-6, the number of live DBM adults in the cage was visually counted. On day-10, the number of DBM larvae and pupae was counted. The plants were removed, and the number of adults introduced on day 0 (dead or alive) and the larvae and pupae of the next generation were counted. The experiments for each type of food-feeding device were repeated three times on three experimental days in the climate-controlled room. <strong>Food-feeding </strong><strong>devices</strong> In the acrylic cage, we used two different types of food-feeding devices to feed the adults. The first type had a wide accessible space for DBM adults: a plastic rectangular dish (14.0 cm × 10.0 cm × 1.5 cm) with a sheet of cotton wool in which the food source (100 mL) was impregnated (dish device). The second type was originally designed to feed <em>C. vestalis</em> which has a narrow accessible space for DBM adults: a glass vial (3.0 cm diameter; 5.8 cm height: 30 mL) with a yellow lid through which a fiber rod (1.2 cm diameter; 7.0 cm height) was vertically pierced was used to supply food (vial device) (revision of Shimoda et al., 2014). The vials were filled with 25 mL of sugary food. 
description: # Fecundity of diamondback moth females when offered honey with pyridalyl,
 a selective insecticide
 [https://doi.org/10.5061/dryad.q573n5tq3](https://doi.org/10.5061/dryad.q573n5tq3) Data contents: Figure 1. (a) Survival curves of female diamondback moths maintained under the water, honey, and honey + pyridalyl conditions in a glass tube for 10 days. (b) The relative number of adults survived on the three experimental day under the water, honey, and honey + pyridalyl conditions in an acrylic cage. Figure 2. Number of diamondback moth eggs per day in the glass tube. Figure 3. (a) Total number of diamondback moth eggs in the glass tube during day 10. (b) Numbers of diamondback moths (larvae and pupae) in an acrylic cage.