A technique for rearing the harmful mushroom fly Neoempheria ferruginea, in the sawdust-based cultivation of shiitake, Lentinula edodes, using shiitake mycelial blocks was developed. One male and one female fly were placed in a polyethylene bag with a stalk of shiitake mushroom and a sheet of filter paper moistened with distilled water for the female to deposit eggs. The eggs were picked up, placed on another filter paper using forceps, and the filter paper was placed on an unwrapped mycelial block. The larvae grew by eating the surface of the mycelial blocks and fruit bodies protruding from the mycelial blocks. They then pupated on the surfaces of the mycelial blocks. When a mycelial block was used immediately after unwrapping, or when the fruit bodies were left as larval food, the emergence rate from inoculated larvae was high, the developmental time from egg to adult decreased, and large pupae were obtained. The flies were reared from egg to adult at combinations of five temperatures (12, 15, 20, 23, and 25°C) and two photoperiodic regimes (LD16:8 and LD10:14). The developmental zero (T₀) and thermal constant (K) from egg to adult of males and females reared under LD16:8 were 7.2°C and 293.6 degree-days and 7.3°C and 304.3 degree-days, respectively. By contrast, those of males and females reared under LD10:14 were 7.0°C and 280.5 degree-days and 7.1°C and 293.6 degree-days, respectively.

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The effect of pesticides on the Nauru biotype, a common biotype of Bemisia tabaci in the Ryukyu Islands, was compared with that on the B biotype under laboratory conditions. Twenty-four commercial agrochemicals were tested on adults, third instar larvae, and eggs. Overall, the majority of the pesticides tested were effective (>70% mortality) for Nauru, but not for the B biotype. Fourteen insecticides were effective for all stages of the Nauru biotype, while only two (pyridaben and emamectine benzoate) were effective for all stages of the B biotype. The effects of synthetic pyrethroid, imidacloprid, and some acaricides were clearly greater in the Nauru biotype than in the B biotype. The results suggest that the Nauru biotype is a less important pest than the B biotype because of the greater susceptibility to insecticides of the former.

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Nutritional status of post-overwintering adults of Halyomorpha halys at their hibernating site was investigated in Akita Prefecture, northern Japan from 2000 to 2005. Nutritional levels of the adults were significantly lower than those of pre-hibernating adults, and the fat body did not develop. Additionally, nutritional levels of the adults recently exited from the hibernating site were significantly lower than those of the adults at their hibernating site in April in 2001 and 2002. Almost all the adults given only water in field from late April could not survive until late May in 2002. These observations suggested that post-overwintering adults of H. halys exiting from the hibernating sites cannot survive for a long period, if they cannot feed on their suitable food plant.

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To understand the biological functions of male-produced pheromone of Nezara antennata Scott, we investigated the physiological status of N. antennata attracted to conspecific adult males. Most females captured in traps baited with adult males had immature ovaries and were unmated. Males attracted in July had entirely undeveloped ectodermal accessory gland, which are involved in reproduction. Many adults were attracted from June to July, when the bugs were considered to be in summer diapause. It is suggested that N. antennata use the volatiles emitted by adult males for reasons other than as mating cues. The nutritional status of most N. antennata adults captured in traps was poor. These results suggested that N. antennata use the volatiles emitted by adult males as cues to find food.

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The diel activity pattern of Neoempheria ferruginea, a harmful fungus fly in the sawdust-based cultivation of shiitake, Lentinula edodes, was studied at 20°C under a photoperiodic regime consisting of a 16-h photophase and an 8-h scotophase. Adult eclosion occurred at photophase in 93% of males and 95% of females. Adult activities showed two peaks: one around when the light was turned off and the other soon after the light was turned on. Copulation occurred mainly around when the light was turned off (40%)or on (40%). These results suggest that the adults are active mainly at dusk and dawn under natural conditions. The duration of copulation was 16.6±7.7 h (mean±SD).

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The bean webworm, Pleuroptya ruralis (Scopoli), is known as a serious pest of soybeans. The overwintering generation and summer generation use the nettles (Urticales, Urticaceae) and soybeans as host plants, respectively. Parasitoids of P. ruralis larvae were investigated in nettle colonies and soybean fields in 2009 and 2010. Eleven species of parasitoids that belong to Braconidae, Ichneumonidae and Bethylidae emerged from the P. ruralis. Percentage parasitism in overwintering generation is higher than that in summer generation. The predominant parasitoid in overwintering generation was Macrocentrus cingulum Brischke in Braconidae .

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We evaluated the efficiency of a pheromone trap for monitoring the sorghum plant bug, Stenotus rubrovittatus. The most effective trap position in a paddy field was ≥7 m inside the field's edge. We also evaluated the pheromone trap as an alternative to capture by sweeping. The number of males captured in traps increased before the increase by sweeping three paddy fields. These results suggest that the pheromone trap can be utilized as a tool to support the decision for control or damage estimation of S. rubrovittatus in the early stage of insect invasion into paddy fields.

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