Spodoptera exigua, beet armyworm

Z)-9-tetradecenyl acetate [16725-534] CH3(CH2)3CH=CH(CH2)8OOCCH3 southern armyworm, Spodoptera eridania (with (Z)-9,(E)-12-tetradecadienyl acetate) beet armyworm, Spodoptera exigua... 

From females of the beet armyworm, Spodoptera exigua, the (Z,E)- and (Z,Z)-tetradecadienyl acetates, the (Z)-9- and (Z)-l1-tetradecenyl acetates and tetra-decanyl acetate were isolated and identified. Synthetic mixtures of some of these components attract male moths in field tests. 

The beet armyworm, Spodoptera exigua, is a rather recent pest in Holland, where it is now called the Florida moth. After it was accidentally introduced into the Netherlands in 1976, it immediately became a grave pest in greenhouses, mainly for chrysanthemums and gerberae, but to a lesser extent also for egg-plants. As application of insecticides such as synthetic pyrethroids, initially effective, soon proved to have become inadequate, other methods were needed, and pheromones were investigated as possible alternatives. 

Mrozik et al. [23] have identified a series of novel 4"-amino-4"-deoxyavermect-ins with excellent insecticidal activity. The most effective members of this class are 12 and 13 which show 1,500 fold higher activity than avermectin (abamectin) against beet armyworm, Spodoptera exigua and other lepidopteran larvae. 

The silkworm is a useful insect rather than a pest, and thus it was necessary to determine whether okaramines would also exhibit activity against harmful insects. Okaramines A (1) and B (2) were tested against various harmful insects. As a result, the most active of the 18 okaramines, compound 2 exhibited the same activity against the second instar larvae of the beet armyworm (Spodoptera exigua) as against silkworms, and thus this compound was considered to have potential use in practical applications. 

Van Laecke K, Degheele D. Detoxification of diflubenzuron and teflubenzuron in the larvae of the beet armyworm (Spodoptera exigua) (Lepidoptera Noctuidae). Pestic. Biochem. Physiol. 1991, 40(2), 181-190. 

One effect of these chemical modifications is that DE-175 is intrinsically more active against pest insect species than spinosad. For example, in a laboratory bioassay of topical toxicity to beet armyworm Spodoptera exigua) larvae, DE-175 is 48X more active than spinosad (Table 29.3.3). Similar results are observed in a bioassay of ingestion activity, where DE-175 is 58 x more active on beet army-worm than spinosad. Improved potency of DE-175 is also observed against other lepidopterous insects, though to a lesser degree (Table 29.3.3). 

Differences in the transport and metabolism do not seem to play an important role in tebufenozide s lack of toxicity to coleopteran species. Studies in which a highly susceptible caterpillar species (Spodoptera eridania) and a non-susceptible larval beetle species (Mexican bean beetle, Epilachna varivestis) were fed equal amounts of Relabelled tebufenozide showed surprisingly similar patterns of tebufenozide uptake, metabolism, and overall tissue distribution (13). The minor differences observed in this study were clearly insufficient to account for the greater than 2,800-fold difference in tebufenozide susceptibility between these two species (LC50 = 0.7 ppm for Spodoptera, >2,000 ppm for Epilachna) (12). Studies comparing beet armyworm (Spodoptera exigua) with Colorado potato beetle (Leptinotarsa decemlineata) yielded similar results (15). 

TBW = tobacco budworm, Heliothis virescens BAW = beet armyworm, Spodoptera exigua DBM = diamondback moth, Plutella xylostella ppm = parts per million... 

Tanada (57) reported that the Hawaiian strain of the armyworm, ftewda/et/a unipuncta, granulosis virus (GV) enhanced infectivity of the armyworm NPV when they were fed simultaneously. Since then, a viral lipoprotein in the GV occlusion body was identified as the synergistic factor (SF). Preliminary tests indicated that the SF enhanced infectivity of GVs and NPVs of the armyworm, the cabbage looper (Trichoplusia ni and the beet armyworm (Spodoptera exigua) in their respective hosts (38). Uchima et sd. (59) demonstrated that the SF binds to midgut membranes and may serve as attachment sites for the enveloped virions. 

Spodoptera eridania (Lepidoptera Noctuidae) - the southern armyworm. This species was chosen for study because it is closely related to S. exigua, the beet armyworm, an insect which has periodically damaged fields of cultivated sunflower in the southern Great Plains (47). A laboratory colony of Sj, exigua could not be successfully maintained. Both S eridania and S. exigua are termed generalist feeders because they can feed on various organs of a variety of taxonomically-unrelated plants (48, 49). Experiments on S. eridania were performed in collaboration with Dr. K. Nakanishi s laboratory at Columbia University. 

Spodoptera exigua (beet armyworm) Brassicas, cotton, finiting vegetables, vegetables leafy... 

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