Recently, poleward range expansions in association with recent climate warming have been reported in several species around the world. In Japan, Nezara viridula, a serious pest of various crops, has been expanding its range northward, possibly due to climate warming. Data on the current distribution and accurate prediction of range expansion are important for pest management. Here, we show that the current distribution of N. viridula in the Kinki district has been expanded northward. Moreover, comparison of the current distribution with the data from five and fifty years ago reveals that the speed of range expansion has accelerated. In addition, the current distribution cannot be simply explained by temperature, which was previously believed to determine the northern limit of N. viridula, because the temperature in the current northern limit area does not meet the conditions. This suggests that factors other than temperature are also involved in the northward range expansion of N. viridula. To understand the impact of climate warming on the northward range expansion, it is important to consider not only temperature but also other factors, including physiological and/or behavioral adaptations.

View full abstract

Courtship behavior of the pear barkminer moth, Spulerina astaurota (Meyrick) (Lepidoptera: Gracillariidae), was investigated under laboratory conditions. Female moths showed a calling posture, i.e. exposing abdominal tips with the wings raised, mainly in the middle of the scotophase. Mean mating duration of 26 pairs was 82.9±5.0 min. Males responded to virgin females by showing a series of six behavioral components; orientation walk with fierce antennal swing (OW), orientation flight (OF), landing on female (LF), touching a female's abdomen (TF), abdominal contact (AC) and copulation (CP). One female equivalent of a crude pheromone extract and several doses of a synthetic pheromone universally elicited OW, OF and LF in 1-day-old and older males, mainly 4.5–7.5 hours after lights off, but 0-day-old males mainly showed these mating behaviors at and after 6.5 hours after lights off. While a similar frequency of OW, OF and LF was observed at various doses of the synthetic pheromone, the response of some males exposed to 10 and 100 ng synthetic pheromone stopped at the OW.

View full abstract

Field experiments were replicated three times from 2008 to 2011 to evaluate the effectiveness of a polyphagous indigenous predator, Campylomma chinensis, to control Frankliniella intonsa and Bemisia tabaci in sweet pepper greenhouses in Okinawa, southwestern Japan. C. chinensis was released three or four times in each trial, with a density of one adult per plant per release (0.5 adults/m²). The C. chinensis population was successfully established in the greenhouse in all experiments. The density of F. intonsa in the greenhouse where C. chinensis was released was consistently lower than that in the non-released greenhouse in all experiments. The density of B. tabaci in the greenhouse where C. chinensis was released was lower than that in the non-released greenhouse except for one experiment in which the density of B. tabaci did not increase in the non-released greenhouse. The percentage of fruit damaged by F. intonsa and B. tabaci was also examined in two of the three experiments; the percentage in the C. chinensis-released greenhouse was consistently lower than that in the non-released greenhouse in both experiments. These results strongly suggest that C. chinensis is a promising biological control agent for F. intonsa and B. tabaci in sweet pepper greenhouse cultivation.

View full abstract

The seasonal prevalence of the sycamore lace bug, Corythucha ciliata (Say) (Heteroptera: Tingidae), infesting sycamore trees (Platanus spp.) planted along a street was surveyed in Kyoto city, Kyoto Prefecture, from 2007 to 2008. In 2007, C. ciliata adults appeared from early May, and increased in numbers from late July, peaking in late August. Nymphs were found from mid-May to mid-September, and numbers peaked in mid-August. Eggs were found from early May, peaking in early August. In 2008, adults appeared from late April, and increased in number from early July, peaking in mid-August. Nymphs were found from late May, with numbers peaking in late July. Eggs were found from late April, peaking in early July. The population densities of adults and nymphs in 2008 were less than those in 2007. The degree of seasonal damage to Platanus spp. caused by C. ciliata was also surveyed in Kyoto city. In 2007, the degree of damage increased from mid-July, and peaked in mid-September. In 2008, the degree of damage peaked in mid-August. To suppress C. ciliata, light pruning and defoliation of the trees were carried out in early August. As a consequence, the degree of damage decreased after late August.

View full abstract

An anthocorid bug species, Dufouriellus ater (Dufour, 1833), which was abundantly collected by light trap for stored food insect pests in a factory in Gunma Prefecture, is recorded from Japan for the first time. This species is known mainly from the Holarctic Region, and recently introduced to the South America and Hawaii. Introduced populations in North America and Hawaii have been found from stored products and wood products. It is assumed that this species has been accidentally introduced to Japan recently as its occurrence is mainly restricted to certain areas in Kantô District. Brief notes on the diagnostic characters and biological information are also provided.

View full abstract

The larvae of the fungivorous moth Diomea cremata were reared using two commercial artificial diets for herbivorous insects. One diet consisted of INSECTA LFM (Nosan Co.) and dried shiitake mushroom, Lentinula edodes, powder at the ratio of 7 : 3. The other diet was ready-to-use, INSECTA LFS (Nosan Co.). The emergence rates from 1st instar larvae were not significantly different between the two diets. It was clarified that larvae of the fungivorous moth D. cremata could be reared on artificial diets for herbivorous insects.

View full abstract