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The developmental times and reproduction of the burdock-infesting aphid, Uroleucon gobonis （Matsumura）, were determined at different temperatures. The developmental zero, effective cumulative temperature, and intrinsic optimum temperature for the development of this aphid were estimated to be 5.27°C, 141.71 degree-days, and 19.22°C, respectively. This species had growth retardation at 27°C, and no nymphs reached the adult stage at 32°C. Like other aphids, it was found to be strong against low temperatures and weak against high temperatures. The intrinsic rate of natural increase of U. gobonis was 0.26 at 12°C, followed by 0.29 at 17°C, and 0.51 at 22°C suggesting that U. gobonis has a higher reproductive ability at low temperatures than other reported aphid species. Assessment of insecticide susceptibility using the leaf and body dipping methods showed that U. gobonis was highly susceptible to the recommended field rates of the 10 insecticides tested. Clothianidin granules（6 kg/10 a）applied to depths of 2 or 5 cm in the soil significantly suppressed aphid densities compared to surface treatment and the nontreated control. Acetamiprid granules（6 kg/10 a）also showed the same effect as clothianidin granules（6 kg/10 a）on the aphid density, and halving the dose showed no reduction in effectiveness. [ABSTRACT FROM AUTHOR]

The toxicity of 85 insecticides, 20 acaricides, 70 fungicides, and 15 spreaders was tested against the predatory mite, Neoseiulus californicus（McGregor）（Acari: Phytoseiidae）. Four neonicotinoids, 1 sulfoximine, 2 pyridine azomethine derivatives, 2 Bacillus thuringiensis and the insecticidal proteins they produce, 6 benzoylureas, 1 buprofezin, 3 diacylhydrazines, 1 oxadiazine, 1 semicarbazone, 6 diamides, flonicamid, pyridalyl, flometoquin, 9 acaricides, 4 spiracle-blocking insecticides, 52 fungicides, and 13 spreaders were harmless to the survival of adult females and immature individuals. These pesticides had little effect on the survival of adult females but 2 neonicotinoids, 1 semicarbazone, flometoquin, 3 acaricides, 2 spiracle-blocking insecticides, 11 fungicides, and 4 spreaders reduced the fecundity. The residual toxicity of 7 insecticides, 6 acaricides, and 5 fungicides were examined against the adult females. These pesticides could be divided into 3 groups: Group A（materials that were harmful as less than 14-day-old residues）: fenitrothion, imidacloprid, spinosad, spinetoram, emamectin, milbemectin, bifenazate, and pyflubumide ＋ fenpyroximate, Group B（materials that were harmful as 14- to 21-day-old residues）: thiamethoxam, spirotetramat, etoxazole, propineb, mancozeb, and chinomethionat, and Group C（materials that were harmful as 21- to 28-day-old residues）: amitraz, pyridaben, thiophanate-methyl, and diethofencarb ＋ thiophanate-methyl. [ABSTRACT FROM AUTHOR]

We examined the susceptibility of two populations of soybean pod borer, Leguminivora glycinivorella Matsumura（Lepidoptera: Tortricidae ）, in Tottori Prefecture to five insecticides: diamides （chlorantraniliprole and flubendiamide）, organic phosphorus（MEP）, synthetic pyrethroid（etofenprox）, and neonicotinoid（acetamiprid）. For both populations, we detected decreasing susceptibility to diamides and synthetic pyrethroid, and organic phosphorus and neonicotinoid were highly toxic. Soybean farmers in Tottori Prefecture use chlorantraniliprole and etofenprox, but not flubendiamide, for pest control, suggesting that cross-resistance may develop between chlorantraniliprole and flubendiamide. To manage diamide resistance in the soybean pod borer in the future, pest management systems should be updated or improved. [ABSTRACT FROM AUTHOR]

We investigated the efficacy of various insecticides, including diamide, on the oriental tea tortrix, Homona magnanima Diakonoff (Lepidoptera: Tortricidae), a major pest of tea (Camellia cinensis), in Kagoshima Prefecture, Japan. The results showed that diamide insecticides had low efficacy against the oriental tea tortrix in the southern part of the prefecture (Nansatsu region; Makurazaki City, Minamikyushu City). The LC50 values ranged from 28.26 to 267.62 ppm(Resistance Ratio(RR): 41.0–387.9)for flubendiamide, 40.60 to 67.75 ppm(RR: 24.9–41.6)for chlorantraniliprole, and 40.33 to 107.49 ppm (RR: 93.8–250.0) for cyantraniliprole, indicating that the oriental tea tortrix has developed resistance to diamide insecticides. The insecticides other than diamide and benzoylurea IGR were highly effective. However, in other areas of the prefecture, all insecticides(including diamide)tested showed high efficiency. Furthermore, crossbreeding experiments showed that diamide resistance is autosomal, incompletely recessive. In the future, it is necessary to monitor the recovery of susceptibility against diamide insecticides in the Nansatsu region while avoiding the expansion of resistance development. [ABSTRACT FROM AUTHOR]

I investigated the impact of insecticide application on the population density of Panonychus citri （McGregor）in two citrus orchards in Shizuoka Prefecture with different species of mite predators. In one citrus orchard, Neoseiulus californicus（McGregor）was the main mite predator species. The application of tolfenpyrad reduced the density of N. californicus and resulted in an increase of P. citri, whereas the application of imidacloprid or chlorfenapyr did not affect the densities of N. californicus and P. citri. In the other citrus orchard, Stethorus spp. were the main mite predator. The application of imidacloprid reduced the density of the predators and increased the density of P. citri, whereas the application of chlorfenapyr did not affect the density of P. citri and the predators. The application of tolfenpyrad reduced the density of the predators, but P. citri did not increase. These results demonstrate that biological control of P. citri requires careful selection of insecticides that will not have a detrimental effect on the regionspecific species of mite predators in citrus orchards. [ABSTRACT FROM AUTHOR]

A new artificial arena was developed for efficient toxicological tests of generalist phytoseiid species. The toxicity of 22 insecticides and 7 acaricides was tested against four native species, Amblyseius eharai Amitai and Swirski, Amblyseius tsugawai Ehara, Euseius sojaensis（Ehara）, and Typhlodromus vulgaris Ehara, which are abundantly found in fruit orchards in Japan. Flubendiamide, chlorantraniliprole, cyantraniliprole, diflubenzuron, teflubenzuron, flonicamid, and pyrifluquinazon were harmless or slightly harmful to the survival and fecundity of adult females and immature individuals in all four species tested in this study. Buprofezin and Bacillus thuringiensis were also slightly toxic to adult females and immature individuals except those of E. sojaensis. All neonicotinoids had little effect on the survival of adult females but they reduced the fecundity. Although the effects of neonicotinoids on the fecundity and survival of immature individuals varied among the different chemicals and phytoseiid species, thiacloprid and dinotefuran were moderately toxic to all four species. Thiamethoxam was also moderately toxic for all species except E. sojaensis. Fenitrothion, permethrin, bifenthrin, silafluofen, spinosad, and spinetoram were toxic to all four species. Among acaricides, cyflumetofen and pyflubumide were nontoxic or slightly toxic to all four species. Furthermore, cyenopyrafen was nontoxic or slightly toxic to adult females and immature individuals except immature E. sojaensis. [ABSTRACT FROM AUTHOR]

An assessment method wherein an aphid colony-infected leaf disk was dipped in an insecticide for 10 s and placed in a plastic zipper bag was developed to easily estimate the number of surviving aphids. This number after 48 h could be estimated by counting the number of honeydew droplets produced by aphids in the bags after 24 h. Although this survey method cannot accurately calculate the mortality rate, it is easy and inexpensive. Therefore, this method is considered to be useful as a simple method for estimating the number of surviving aphids and as a method for easily determining insecticides with reduced effects. [ABSTRACT FROM AUTHOR]

We investigated the efficacy of insecticides to control the tea leaf roller, Caloptilia theivora, which is a majorpest of tea fields throughout Kagoshima Prefecture. Benzoylurea analog insect growth regulator insecticide（s IGRs）exhibited low efficacy against the tea leaf roller in the Nansatsu region（Makurazaki City, Minamikyushu City）. Ina subsequent investigation on the sensitivity of different tea leaf roller populations in different regions of KagoshimaPrefecture, the LC50 for flufenoxuron in the Nansatsu population was found to range from 21.5 to 57.0 ppm（resistanceratio of 239- to 356-fold）, confirming the population’s reduced sensitivity. We speculate that this is due to the continuoususe of this chemical to control a range of insects, including the tea leaf roller, for more than ten years. In addition,benzoylurea analog IGRs exhibited high efficacy in all other populations outside the Nansatsu region. Meanwhile, diacylhydrazineanalog IGRs（methoxyfenozide）, neonicotinoid（dinotefuran）, and diamide（chlorantraniliprole）wereconfirmed to be effective against the tea leaf roller in all regions of the prefecture. In the future, it will be important toimplement integrated pest management using insecticides with different modes of action depending on the region. [ABSTRACT FROM AUTHOR]

The whitefly Bemisia tabaci （Gennadius） is an important economic pest, being a vector of Tomato yellow leaf curl virus （TYLCV）. In this study, we evaluated the inhibitory effect of two insecticides on TYLCV transmission by whiteflies. Tomato plants pretreated with pyrifluquinazon or dinotefuran （0 and 7 days before inoculation） were significantly less infected with TYLCV than untreated plants, while plants pretreated 14 day before inoculation did not show any difference. In contrast, the survival rates of viruliferous whitefly on pretreated plants 0, 7, 14 days before inoculation were significantly lower than those on untreated plants. These results indicate that sprays of these insecticides at 7-day intervals were effective in inhibiting the incidence of TYLCV transmission by whiteflies. [ABSTRACT FROM AUTHOR]

Human biomonitoring (HBM) is a technique to evaluate chemical exposure level by measuring the levels of chemicals or related substances such as their metabolites or adducts in biological samples (e.g., urine or blood). Compared with exposure assessment by an approach to estimate insecticide intake from diet or the environment, HBM can provide information more specific to an individual exposure dose and can reflect the exact body burden condition at the time of measurement. If the analytical sensitivities, completeness and cost-effectiveness of the method are improved further, HBM might be widely applicable to not only research fields such as epidemiological and occupational study but also routine analysis for effective prevention of the exposure of the human body to chemical substances. In this article, we provide an overview of HBM as a determination method for insecticide exposure markers in urine and its applications, and discuss future research perspectives in the field of environmental and occupational health.