Search

Cryptophlebia distorta (Hampson, 1905) (Tortricidae, Olethreutinae) is recorded from Honshu (Tomogashima Is., Wakayama Prefecture) for the first time. The larva fed on Glochidion obovatum boring into the fruit. The plant was newly recorded as host plant of the moth. The male adult and its genitalia are illustrated. [ABSTRACT FROM AUTHOR]

The locomotor activity of unmated adult Leguminivora glycinivorella（Matsumura）（Lepidoptera: Tortricidae）immediately after emergence was recorded under various photoperiods using an actograph in an incubator. Under a 12L : 12D photoperiod, both sexes displayed an approximately 24-hour cycle rhythm consisting of active and resting periods. Activity was observed around switching from the light to dark period. Under constant dark conditions, rhythms similar to those in the 12L : 12D photoperiod were observed, indicating that the activity is controlled by a circadian clock. The activity phase receded as the beginning of constant darkness was delayed, and the beginning of constant darkness was almost coincident with the median of activity, suggesting that the light stimulus that switches from light to dark is a zeitgebers of the circadian clock. Under constant light conditions, three out of five males and two out of five females were found to have lost their periodicity. Even in the individuals that showed periodicity, there was a significant decrease in 24-hour activity in males and a loss of rhythm after the second day of emergence in females, suggesting that constant light conditions disrupt the circadian clock. Artificial light irradiation at night may suppress mating behavior in soybean fields, leading to damage suppression. [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 evaluated the effects of tannic acid and four major catechins present in tea on the insecticidal activity of Bacillus thuringiensis serovar kurstaki formulation against Adoxophyes honmai Yasuda (Lepidoptera: Tortricidae) using the oral administration method. We also evaluated the insecticidal activity of B. thuringiensis against A. honmai using the leaf dipping method with tea leaves plucked in different tea seasons in 2010 and 2011: in May (hereafter referred to as 1st tea), June to July (hereafter referred to as 2nd tea), August to mid-September (hereafter referred to as 3rd tea), and late September to October (hereafter referred to as 4th tea). The catechin content was measured at the time of each harvest in 2011. Tannic acid and catechins decreased the B. thuringiensis activity in a dose response-dependent manner. The insecticidal activity was decreased by the late tea season and was found to be lowest in the 4th tea. The content of the catechins in the four seasons was in the following order: 2nd tea ＞ 3rd tea ＞ 4th tea ＞ 1st tea. Though these results suggest no direct relationship between the content of catechins and insecticidal activity on tea leaves, other factors might be involved to influence the effects of B. thuringiensis. [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]