Armyworms

Mayer and coworkers128 discovered that kojic acid is a moderately effective activator for nicotine insecticides. When tested against the melon worm (Diaphania hyalinata L.) and the southern armyworm (Prodenia eridania Cram.), kojic acid (alone) was not toxic but the toxicity of a 5% nicotine sulfate-pyrophyllite dust was increased 35 %, and that of a 5 % nicotine bentonite-bentonite spray by some 50%, by the addition of 5% of kojic... 

Highly toxic substances, such as cyanides, are sometimes feeding cues and stimulants for specialized insects. For example, instar larvae of the southern armyworm (Spodoptera eridania) strongly prefer cyanogenic foods, such as foliage of the lima bean, a plant with comparatively elevated cyanide content — up to 31 mg/kg in some varieties — in the form of linamurin (Brattsten et al. 1983). Feeding was stimulated in southern army worms at dietary levels up to 508 mg KCN/kg... 

Experimental studies with southern armyworm larvae and thiocyanate — one of the in vivo cyanide metabolites — showed that 5000 mg thiocyanate/kg diet reduced pupation by 77%, completely inhibited oviposition, and reduced adult emergence by 80% (Brattsten et al. 1983), strongly suggesting that thiocyanate poisoning is the primary effect of high dietary cyanide levels in southern army worms. 

Resistant species, such as southern armyworms, require injected doses up to 800 mg KCN/kg BW (332 mg HCN/kg BW) or diets of 3600 mg KCN/kg for 50% mortality (Brattsten et al. 1983), but data are scarce for other terrestrial invertebrates. Exposure to 8 mg HCN/L air inhibits respiration in the granary weevil (Sitophilus granarius) within 15 min and kills 50% in 4 h some weevils recover after cessation of 4-h exposure (Towill et al. 1978). 

Brattsten, L.B., J.H. Samuelian, K.Y. Long, S.A. Kincaid, and C.K. Evans. 1983. Cyanide as afeeding stimulant for the southern armyworm, Spodoptera eridania. Ecol. Entomol. 8 125-132. 

Wadleigh RW, Yu SJ (1987) Glutathione transferase activity of fall armyworm larvae toward alpha-, beta-unsaturated carbonyl allelochemicals and its induction by allelochemicals. Insect Biochem 17 759-764... 

Yu SJ (1982) Host plant induction of glutathione S-transferases in the fall armyworm. Pestic Biochem Physiol 19 101-106... 

Yu SJ (1983) Induction of detoxifying enzymes by allelochemicals and host plants in the fall armyworm. Pestic Biochem Physiol 19 330-336 Yu SJ (1984) Interactions of allelochemicals with detoxification enzymes of insecticide-susceptible and resistant fall armyworms. Pestic Biochem Physiol 22 60-68 Yu SJ (1986) Consequences of induced foreign compound-metabolizing enzymes in insects. In Brattsten LB, Ahmad S (eds) Molecular aspects of insect-plant associations. Plenum, New York, pp 153-174... 

In Mexico there exist two major insect pests of corn, an armyworm Laphygma frugiperda (A. S.), which breeds and feeds in the leaf whorls of young corn, and the larvae of certain coleoptera which inhabit the soil and feed upon the roots of the corn plants. Of these two the armyworm is the most important. Its attack is particularly severe on corn grown during the summer but, as it is able to breed continuously, it is a problem in corn grown throughout the year in the tropics. 

In vitro dieldrin production increased proportionally to larval concentration (enzyme concentration) up to 5 larvae/ml and each 10X increase in substrate (aldrin) concentration tripled and doubled, respectively, dieldrin formation. An approximation of 2 X 10-5 M aldrin as the Km value for midge epoxidase was obtained from a double reciprocal plot of data in Table VII, which closely corresponds to values for aldrin epoxidase in the house fly (28) and the southern armyworm (11). 

Electron microscopic examination of midge microsomes prepared by a slightly different procedure than Table VIII revealed a homogeneous mixture of vesicles derived from rough and smooth endoplasmic reticulum, ribosomes and a few mitochondria. Midge preparations are similar in composition to microsomal fractions of southern armyworm fat body and gut (44). 

Ground Beetles Large, shiiy, dark brown beetles Feed on caterpillars, armyworms and cutworms... 

Cuts from the silica gel column were incorporated into artificial diets optimized for several economically-important agricultural pest insects, the pink bollworm Pectinophora gossypiella> the tobacco budworm Heliothis virescens> the corn earworm H. zea and the fall armyworm Spodoptera frugiperda. > Monitoring with this artificial diet bioassay, further column chromatography and preparative TLC on silica gel in diethylether-petrol yielded five... 

Although southern armyworms were used for the development of QSARs the other insects listed in Figure 2 were used in topical or foliar assays to monitor spectrum and performance under field conditions. 

It was clear, from even a qualitative inspection of the data, that the presence of a methyl or fluoro group in the meta position had the effect of not only increasing activity versus the design insect, the southern armyworm, but also lead to dramatic increases in level of topical activity against other species. 

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