• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.154-159
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• 1996

To isolate Bacillus thuringiensis toxic to Spodoptera species, we collected soil samples in Korea. In these samples, we characterized 7 B. thuringiensis isolates toxic to spodoptera exigua or S. litura from soil, granary and sericultural farm samples. The 7 isolates were named B. thuringiensis STB-1, STB-2, STB-3, STB-4, STB-5, STB-6 and STB-7, respectively. The bioassay of these isolates against S. exigua and S. litura showed highly insecticidal activity. The serotypes of them were determined by agglutination tests using 33 antisera ; STB-1 an STB-2 are identical to B. thuringiensis subsp. kurastaki, and STB-3, STB-4 and STB-5 are identical to subsp. kenyae. STB-6 and STB-7 did not react with 33 antisera. STB-1 and STB-3 which have different gene types from B. thuringiensis subsp. kurastaki and subsp. kenyae are identified new isolates. STB-6 and STB-7 which show no agglutination in serological tests havd cryIA(a), cryIA(b), cryIC, and cryII genes are also identified new isolates. Molecular weights of parasporal inclusions of all isolates were determined approximately 130 kDa by SDS-polyacrylamide gel elctrophoresis.

• Animal cells and systems
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• v.1 no.3
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• pp.457-462
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• 1997

Antibacterial activity was induced in the haemolymph of the common cutworm, Spodoptera litura by the artificial injection of E, coli Ek132. Antibacterial peptides were purified from the immunized haemolymph by heat treatment, ion-exchange chromatography, gel filtration chromatography, and reverse phase FPLC, and their physicochemical characteristics were investigated. These purified antibacterial peptides designated as spodopsin la and Ib were named after Spodoptera litura. Spodopsin la and Ib had the apparent molecular masses of 3, 823 Da and 3, 886 Da, respectively, and about 20% of the sequences had basic amino acids, such as lysine and arginine but no cysteine. Also, spodopsin l was confirmed to be a new member of cecropin family having a similar amino acid sequence to cecropin of lepidopteran insects, such as Bombyx mori and Hyalophora cecropia. The purified spodopsin was active against gram-positive as well as gram-negative bacteria.

• International Journal of Industrial Entomology and Biomaterials
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• v.32 no.2
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• pp.60-68
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• 2016

Pheromone orientation in moths is an exemplar of olfactory sensitivity. To avoid cross mating, the responses of males to pheromone blends must be high specificity and temporal resolution. We tested the effects of olfactory self- and cross-adaptation of pheromone compounds and mixtures in Spodoptera litura moths by electroantennogram (EAG) recordings. The challenge of S. litura antennae to a pulse train of its own pheromone blends of Z9,E11-14:OAc and Z9,E12-14:OAc with 200 ms on/off and 1 s on/off indicated that the repetitive stimulation by 200 ms on/off with high dosages resulted in greater adaptation than that by 1 s on/off with low dosages and the adaptation index of Z9,E11-14:OAc in all treatments is significantly larger than that of Z9,E12-14:OAc, suggesting that high dosages with more frequent stimulation prefer to induce sensory adaptations and a different odor coding exist between the two components in the antennal periphery in this moth. The cross-adaptation EAG test among the two pheromone compounds and Z7-12:OAc and Z9-14:OH from congeneric species of S. litura showed that each of these compounds adapted the antenna more to that specific compound. The significantly higher adaptation to Z7-12:OAc and Z9-14:OH than to the pheromone components of S. litura induced by themselves suggested that both of them are coded by specific odor receptor neurons which are different from those tuned to the pheromone components of S. litura . Thus, we proposed that Z7-12:OAc and Z9-14:OH may play an important role in avoidance of heterospecific mating between S. litura and its sympatric moth species.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.149-149
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• 2016

Pheromone orientation in moths is an exemplar of olfactory sensitivity. To avoid cross mating, the responses of males to pheromone blends must be high specificity and temporal resolution. We tested the effects of olfactory self-and cross-adaptation of pheromone compounds and mixtures in Spodoptera litura moths by electroantennogram (EAG) recordings. The challenge of S. litura antennae to a pulse train of its own pheromone blends of Z9,E11-14:OAc and Z9,E12-14:OAc with 200 ms on/off and 1 s on/off indicated that the repetitive stimulation by 200 ms on/off with high dosages resulted in greater adaptation than that by 1 s on/off with low dosages and the adaptation index of Z9,E11-14:OAc in all treatments is significantly larger than that of Z9,E12-14:OAc, suggesting that high dosages with more frequent stimulation prefer to induce sensory adaptations and a different odor coding exist between the two components in the antennal periphery in this moth. The cross-adaptation EAG test among the two pheromone compounds and Z7-12:OAc and Z9-14:OH from congeneric species of S. litura showed that each of these compounds adapted the antenna more to that specific compound. The significantly higher adaptation to Z7-12:OAc and Z9-14:OH than to the pheromone components of S. litura induced by themselves suggested that both of them are coded by specific odor receptor neurons which are different from those tuned to the pheromone components of S. litura. Thus, we proposed that Z7-12:OAc and Z9-14:OH may play an important role in avoidance of heterospecific mating between S. litura and its sympatric moth species.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.77-83
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• 2022

This study was conducted to determine the optimal composition of sex attractant for monitoring adults of the tobacco cutworm, Spodoptera litura, in Korea. Lures of different compositions from the two sex pheromone components the female, (Z,E)-9,11-tetradecadienyl acetate (Z9E11-14:Ac) and (Z,E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac), were compared for male attraction using synthetic chemicals, rubber septa, and funnel traps in soybean and peanut fields. After sequential tests were conducted using three sets of the two components different ranges from 5:5 to 10:1, from 9:1 to 99:1, and from 9:1 to 39:1, the 19:1 ratio was identified as the most efficient composition. However, S. litura males were barely caught in the trap of the Z9E11-14Ac single component lure. The results show that both the sex attractant compounds are necessary for monitoring adults S. litura males. The higher the pheromone amount in the dispenser in the range from 0.1 to 10 mg, the more males were attracted. Furthermore, the trap height of 1.5 m was optimal for male capture.

• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.1
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• pp.87-91
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• 2007

A diverse kind of environment-friendly agricultural materials(EFAM) for the control of insect pests is on the market. These EFAMs are a part of essential sources for the accomplishment of successful, sustainable, and environment-friendly agriculture. Thus, accurate information of these EFAMs is one that required for the success of environment-friendly agriculture, but, in reality, still appropriate information is absolutely in shortage. In this study, we, therefore, tested the efficacy of commercial EFAMs against two lepidopteran insect larvae, the diamondback moth Plutella xylostella(Lepidoptera: plutellidae) and the tobacco cutworm Spodoptera litura(Lepidoptera: Noctuidae). After the two insect pests were successfully stabilized in indoor environment the larvicidal activity was tested at $24{\pm}1^{\circ}C$, relative humidity(RH) of $60{\pm}5%$, and a photoperiod of 16L:8D, and mortality was determined 48 hrs after EFAMs are treated. The EFAMs that showed more than 90% of larvicidal activity were each six among 16 against both P. xylostella and S. litura and only three of them showed consistent larvicidal activity against both species, signifying species specificity of EFAMs and importance of selection of proper EFAMs depending on target insect pest.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.503-508
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• 1994

Methanol extracts from 45 species of oriental medicinal plants belonging to 17 families were subjected to a screening test for their larvicidal and antifeeding activities against two species of lepidopteran larvae, diamondback moth (Plutella xylostella L.) and tobacco cutworm (Spodoptera litura F.) by a leaf-dipping method. At a concentration of 8,000 ppm, methanol extract of Corydalis turrschaninovii roots only was found to have potent larvicidal activity against S. litura. At 5,000 ppm, strong antifeeding activity against both larvae was observed from the extracts of Clerodendron trichotomum, C. trichotomum var. esculentum, Inura helenium, Arctium lappa, Artemisia messerschmidtiana, Anthriscus sylvestris, Angelica dahurica, and C. turrschaninovii.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.252-256
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• 1990

Viral insecticides were formulated with Spodoptera litura nuclear polyhedrosis virus and different U.V. protectants based on white carbon, molasses, and white carbon and molasses mixture to use as microbial control agents. Effect of rainfall on the attachment of formulated viruses to leaves was no different between the treated and the non-treated experiment. Persistence of the formulations was lated 5 days on the surface-sprayed leaves and 12 days on the under-sprayed leaves which was showing 60% mortality. Total mortality of the viral insecticides was more than 97% with no differences among them. Field evaluation of three viral insecticides in soybean field was very successful then carried out in Chinju, a southern part of Korea. Mortality by the formulation in the field during 14 days was more than 93%, but the formulations contained molasses showed phytotoxicity on soybean leaves. Spray effect of the viral insecticides was begun to appear from 7 days later than that of chemical insecticide.

• Korean journal of applied entomology
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• v.27 no.4
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• pp.211-218
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• 1988

Polyhedral proteins and the endogenous alkaline protease associated with larval-derived polyhedra of nuclear viruses isolated from Spodoptera litura, Bombyx mori, and Hyphantria cunea were investigated. Polyhedral proteins prepared under alkaline protease heat-inactivated condition were separated as one band with 31Kd in S. litura a H. cunea NpV and 30Kd in B. mori NPV by the SDS-polyacrylamide gel electroptoresis. Whereas polyhedral proteins without heat-inactivation were degraded into smaller polypeptides with a certain pattern in alkaline solution. The results of double-immunodiffusion and western blot analysis with antisera against polyhedral proteins indicated that those three polyhedral proteins had common antigenic determinants and the degradation of polyhedral proteins by alkaline protease could be confirmed.

• The Zoological Society Korea : Newsletter
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• v.12 no.2
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• pp.117.2-117
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• 1995