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The Amphipalaearctic tiger moth species Diacrisia metelkana (Lederer, 1861) is reported for Kazakhstan for the first time. Data on species’ bionomics in Kazakhstan and general distribution are provided. Species’ habitats in Kazakhstan are illustrated.

Life table and economic threshold (ET) level of Diacrisia casignetum Kollar on jute was calculated in West Bengal condition during 2016-2018 for environmentally benign management and better production of jute. The demographic data of D. casignetum always construct type-III survivorship curve like most of the insects. Potential fecundity (Pf) and total fertility rate (Fx) were 384.667±5.487 and 30893.60±1063.586, respectively. The average intrinsic rate of natural increase (rm) and the daily finite rate of increase (ë) were 0.106±0.001 and 1.111±0.003 respectively with the generation time (Tc) of 41.520±0.069 and doubling time (DT) of 6.563±0.021 days. Their mean population momentum factor of increase (PMF) was 19.676±0.605 including vital index (VI) and trend index (TI) of 0.522±0.003 and 92.359±2.648, respectively with different levels of significance. The economic injury level (EIL) and ET based on percent yield loss of jute were 7.119±2.166 and 6.385±1.969 pests per plant, respectively. At single pest observation per plant, the possible time taken to reach EIL (Ti) and ET (Tt) were 6.377±3.292 and 5.377±3.292 days, respectively which will be useful for better cultivation of jute and other subsequent crops.

The role of jute, Chorchorus capsularis (cv. Sonali; JRC-321), leaf physicochemical cues in the form of cuticular surface ultrastructures and wax chemicals mainly n-alkanes and free fatty acids (FFAs) on attraction and oviposition preference of Diacrisia casignetum Kollar (Lepidoptera: Arctiidae) was studied under laboratory conditions. The GC–MS and GC-FID analyses of mature jute leaf surface wax indicated the presence of 257.04 and 171.36 µg/leaf n-alkanes and FFAs, respectively. Eighteen n-alkanes from n-C16 to n-C36 and 13 FFAs from C12:0 to C20:0 were detected in the leaf surface wax. The cuticular surface ultrastructures and its chemicals have been demonstrated in this work to serve as cues for eliciting attraction and oviposition responses of the adults to mature jute leaves. The synthetic combination mixture mimicking the natural surface wax components of 4 n-alkanes (n-C17, n-C18, n-C27, n-C29) and 5 FFAs (C16:0, C16:1, C18:1, C18:2, C18:3) was most attractive to D. casignetum adults, whereas same mixtures excluding 2 n-alkanes (n-C27, n-C29) indicated significantly optimum oviposition preference at leaf equivalent (µg/leaf) concentrations that may be used for this pest management program as baited trap. The present study will also ensure sustainability of success in integrated pest management (IPM) in the form of green pest management (GPM) in the near future.

Extraction, thin layer chromatography and gas chromatography-mass spectroscopy analyses revealed 13 free fatty acids in young, mature, and senescent leaves of Helianthus annuus L. (Asteraceae) representing 75.65, 75.38, and 68.01% of total free fatty acids, respectively. α-Linolenic acid, linoleic acid, and linoleic acid were the major free fatty acids in young, mature, and senescent leaves, accounting for 22.71, 31.48, and 30.60%, respectively. The free fatty acids from young, mature, and senescent leaves attracted the female insect, Diacrisia casignetum Kollar (Lepidoptera: Arctiidae) at minimal concentrations of 12.5, 12.5, and 25 µg, respectively; whereas the synthetic mixtures of fatty acids mimicking free fatty acids of young, mature, and senescent leaves attracted at minimal concentrations of 12.5, 12.5, and 50 µg, respectively. Diacrisia casignetum insects showed attraction toward an initial amount of individual synthetic palmitic, palmitoleic, stearic, oleic, linoleic, and α-linolenic acids at 2.39, 4.63, 2.28, 3.08, 29.20, and 25.20 µg, respectively. A synthetic blend of 2.39, 4.90, 4.53, 3.14, 43, and 25.20 µg of palmitic, palmitoleic, stearic, oleic, linoleic, and α-linolenic acids, respectively, the proportion present at 100 µg concentration free fatty acids of mature leaves produced highest attractions for D. casignetum and might be used for insect pest management programme such as baited traps.

Effects of four host-plants, sunflower, castor, jute and sesame, on feeding, growth and reproduction of Diacrisia casignetum Kollar (Lepidoptera: Arctiidae) were studied under laboratory conditions (27 ± 0.5°C, 12 h light : 12 h dark, 65 ± 5% RH). Total larval developmental time of D. casignetum was highest on sesame than the other three host-plants used in this study, but pupal duration was higher on sesame than sunflower but not for other dietary treatments. The longevity of females was generally longer than males. Male and female longevity was higher in sunflower than sesame (P

A phylogenetic model for all the 18 genera of Micrarctiini (Lepidoptera, Arctiidae) of the World fauna is discussed. The SYNAP method was used for development of the model. For these purposes, 47 characters of the general appearance, male and female genitalia, and wing pattern were used. Based on these characteristics, an evolutionary trend from the plesiomorphic to apomorphic states was revealed. The genera Apantesis and Amurrhyparia, as well as Notarctia, differ from the other genera to the greatest extent. The other genera have formed two the main clades: Grammia + (Diacrisia + (Rhyparia + Rhyparioides)). Neoarctia + (Palearctia + Holoarctia + Chelis) and all the other genera have occupied separate positions. The latter group was divided into two clades: Ebertarctia + Tancrea + Divarctia with brachypterous females and Centrarctia + (Sibirarctia + (Micrarctia + Hyperborea)).

27 Diacrisia sannio Rotrandb��r Der Rotrand-B��r fliegt tags��ber bei St��rung aus der Vegetation auf, kommt auch z. T. in gr��sserer Individuenzahl ans Licht. Vertikalverbreitung bis 1900 m; Phaenologie: 21.6. ��� 7.8.; die Talpopulationen sind bivoltin., Published as part of Aistleitner, E., 2014, Biodiversit��tsforschung in Vorarlberg, Austria occ. Zur Schmetterlingsfauna des Verwalls - 1. Teil Tagfalter, Spinner und Schw��rmer (Insecta, Lepidoptera, Diurna, Bombyces et Sphinges sensu, pp. 221-290 in Linzer biologische Beitr��ge 46 (1) on page 257, DOI: 10.5281/zenodo.4526236

Diacrisia sannio 27 Nachweise: n = 29 Kl��sterle, Nenzigast Alpe, 1476 m, 27.+ 28.07.2005, 1.07.2006, 16., 17.+ 18.07.2007, 13., 14.+ 23.07.2009; Silbertal, Wasserstubental, Riedkopf, 1820-1900 m, 20.07.2007; Silbertal, Wildried, 1550 m, 16.07.2007 (M); Silbertal, Unt. D��rrwald Alpe 1470-1500 m, 19.07.2004, 07.07.2008; Silbertal, Unt. Fresch Alpe, 1650 m, 06.08.2008; Silbertal, Ob. Fresch Alpe, 1890 m, 07.08.2008; Silbertal, Ob. Fresch Alpe, Langsee, 1850-1950 m, 05.07.2006; St. Gallenkirch, Zamangweg, 1500 m, 22.07.1978 (D); St. Gallenkirch, 900 m, 03.07.1977 (D); Gaschurn-Partenen, Trilliszug, 1200-1300 m, 21.06.2000; Gaschurn-Partenen, Ganifer Alpe, 1500 m, 21.06.2000; Gaschurn- Partenen, Zeinisjoch, 1820-1840 m, 3.+ 5.08.2002, 22.+ 23.07.2007, 23., 24., 27.+ 28.7.2009; Gaschurn-Partenen, Zeinisjoch, F��dnerspitze 1850-1880 m, 24.07.2007, Published as part of Aistleitner, E., 2014, Biodiversit��tsforschung in Vorarlberg, Austria occ. Zur Schmetterlingsfauna des Verwalls - 1. Teil Tagfalter, Spinner und Schw��rmer (Insecta, Lepidoptera, Diurna, Bombyces et Sphinges sensu, pp. 221-290 in Linzer biologische Beitr��ge 46 (1) on page 289, DOI: 10.5281/zenodo.4526236

27 Diacrisia sannio Rotrandbär Der Rotrand-Bär fliegt tagsüber bei Störung aus der Vegetation auf, kommt auch z. T. in grösserer Individuenzahl ans Licht. Vertikalverbreitung bis 1900 m; Phaenologie: 21.6. – 7.8.; die Talpopulationen sind bivoltin.

Effects of feeding on young, mature, and senescent sunflower leaves were studied under laboratory conditions (27±0.5°C, 12L : 12D,65±5% RH) to evaluate the impact of variation of nutrients on larval food utilization efficiency, larval and pupal development and survival, longevity, and fecundity ofDiacrisia casignetumKollar. The growth rate, which is the ratio between the dry weight gain of insect and duration of experimental period, ofD. casignetumwas in the order of mature leaf > young leaf > senescent leaf of sunflower. This was correlated with nutrient constituents of three kinds of sunflower leaves, which was measured by various biochemical analyses described elsewhere in the text. Total carbohydrates, proteins, lipids, nitrogen, amino acids, and water content are in greater amount in mature leaves when compared to young and senescent leaves, whereas phenol content was highest in young leaves than mature leaves. Hence, higher amount of total carbohydrates, proteins, lipids, nitrogen, amino acids including water and lower amount of total phenol content in mature leaves have influenced higher growth rate, less developmental time, and higher fecundity ofD. casignetum.

Patterns of locomotion of arctiid caterpillars,Diacrisia virginicaFabr., deprived of all external chemosensory organs were recorded in a field where there was patchy distribution of two of the most favored food plants,Plantago majorL. andTaraxacum officinaleWalker, on a background of grass and mixed forbs. Each track traced in the field was retraced on a digitizing tablet from its point of origin in the center of a circle of 30 cm radius to the circumference. The length of the path was a measure of tortuosity. The patterns of paths followed by normal, antennectomized, maxillectomized, and antennectomized + maxillectomized larvae were compared. No differences in meander were found. The ability of larvae of each class to locate, discriminate among, and feed upon food plants was tested in field-plot tests and cafeteria tests. Different degrees of chemosensory deprivation did not affect ability to locate and begin feeding on plants but did impair ability to discriminate among species. Execution of normal patterns of meandering by chemosensorily deprived larvae and successful encounters with food plants support the hypothesis that food-related search behavior by this species of caterpillar is neither initiated nor steered by chemical stimuli provided by food plants.

Models of feeding regulation postulate that chemosensory information from available food both initiates and maintains feeding. However, we find that removing antennae and maxillae (AM) from Manduca sexta and Diacrisia virginica larvae has little effect on amounts eaten, patterns of feeding, and the microstructure (each bite and pause) of feeding, as quickly as two days after the operation. However, there was a small change in the microstructure of feeding of AM D. virginica . Bite frequency of AM D. virginica was significantly lower than for controls when larvae began meals without exploring the food first. Exploring was also followed by longer chewing bouts. Acute effects of the ablation were tested using only Manduca . Six hours after the operation larvae ate less than most controls by eating fewer meals and by biting more slowly. Unilateral ablates also ate less 6 h post-operatively, by eating fewer meals; their bite frequency was not low. These observations suggest that chemosensory input affects bite frequency but not other aspects of feeding. As quickly as 24 h post-operatively other sensory input to the CNS of AM larvae may compensate for the reduction in chemosensory information, but overall, chemosensory input appears relatively unimportant in non-choice situations.

The relationships of Afrotropical tiger moths remain relatively poorly analyzed (see Goodger & Watson 1995), despite some noticeable new generic descriptions (see Goodger & Watson 1995, Dubatolov 2006a, 2006b, 2009, 2009, Dubatolov & Haynes 2008). While studying series of tiger moths from the Natural History Museum and Manchester Museum, some specimens of “ Diacrisia ” epicaste Fawcett, 1915 (synonyms include “ Spilosoma ” occidentalis Bartel, 1903 and “ Amsacta ” melanogastra Holland, 1897) were found to have genitalia unlike any known Spilosomina genus, and are transferred to a newly described genus as follows.

The interactions between the Diacrisia virginica granulosis virus (DGV) and the Hyphantria cunea baculovirus isolates were determined, utilizing defined differences between the time-mortality responses of these viruses fed to H. cunea larvae. The DGV, having a prolonged incubation period, when given an advantage in time or in the number of capsules, was able to prevent the expression of the more lethal H. cunea granulosis virus (HcGV) isolate. The time-mortality response of test larvae simultaneously fed equivalent dosages of HcGV and DGV was intermediate to that achieved with HcGV alone or DGV alone. Larvae infected with the DGV isolate were still susceptible to double infection by the nucleopolyhedrosis virus. The time-mortality response demonstrated that the development of nucleopolyhedrosis was only partly inhibited by preinfecting the test larvae with the DGV isolate.

Laboratory evaluation of food consumption, food utilization, weight gain, development, fecundity and egg-hatchability were made from the beginning of the first instar to sixth instar on castor, groundnut, Indian bean, jute, sesame and sunflower. Total food consumption was highest on castor and lowest on jute. Development was fastest on castor, and castor was most efficiently digested followed by sunflower, sesame, groundnut, Indian bean and jute. Consumption index and digestive efficiency on all host plants declined with larval age. Digested portion of jute was most efficiently converted into body matter. Variations in fecundity and egg-hatchability for different host plants were statistically significant at P = 0.01. The differences in these parameters may be due to the variations in the nutritional quality of the hosts. Une evaluation de la comsomation et utilisation de la nourriture, gain en poids, developpement, fecondite et eclosion des ouefs au laboratoire fut entreprise du premier au sixieme stage larvaire sur les arachides, le zesame, le tournesol, la jute, le pois indien et la ricine. La comsomation totalede la ricine etait la plus elevee mais celle de la jute etait la plus basse. D’autre part le developpement des insectes etait rapide sur la ricine. La ricine fut efficacement digerer et fut suivit du tournesol, du sezame, de l’arachide, du pois indien et de la jute. L’index de la comsomation et l’efficacite digestive fut reduite sur toute les plantes en fonction de l’âge des larves. Les portions de la jute digerees ne furent pas efficacement converties en matieres organiques. Les variations de la fecondite et l’eclosion des ouefs pour les differentes plantes furent statistiquement significatives a P = 0,01. Les differences entre cse parametres sont due peut etre aux variations de la qualite nutritionnelle des insectes.

Larvae of Diacrisia casignetum Kollar were reared in groups of 100, 50 and 10 on fresh sunflower leaves at 27 ± 1°C temperature, 75 ± 5% r.h. and 12 h light each day. Rates of feeding, excretion and weight gain increased with age of the larva and were greatest in the sixth instar. Differences in these rates attributable to density were statistically heterogeneous (P < 0.001) whereas, of those attributable to instar, the weight gain was significant (P < 0.10). The second-instar larvae had highest levels of protein and carbohydrates in the body tissues; and the sixth-instar larvae had, the least. The pattern of protein assimilation in various instars was similar to that of glycogen except that proportional differences in the latter were pronounced in fifth and sixth instars. Consumption index, growth rate and approximate digestibility were high in the early instars whereas efficiencies of conversion of ingested and digested food were high in advanced instars. Food utilization, as reflected by efficiency of conversion of ingested and digested values in advanced instars, indicated the amount needed for maintenance decreased and more energy was left for growth and reproduction.

The biochemical and biophysical characteristics of the closely related Diacrisia virginica and Hyphantria cunea granulosis virus isolates were examined. Sucrose gradient sedimentation patterns of alkali-solubilized DGV and HcGV capsules were identical. The top, middle, and bottom fractions from either viral isolate were infectious when injected into susceptible host larvae. Electrophoretic analysis of alkaline-solubilized granulin extracts demonstrated that both viruses contain alkaline proteolytic activity. The major granulin protein (∼28,000 daltons) of both isolates comigrated in a SDS-PAGE. Electrophoretic separation of the virus proteins demonstrated some quantitative differences between the two granulosis viruses. The enveloped nucleocapsids and the nucleocapsids of the two viruses were morphologically indistinguishable.

The dosage-mortality response of Hyphantria cunea larvae to a granulosis virus isolated from Diacrisia virginica was studied. Serial decimal dilutions of the D. virginica granulosis virus were fed to early second-instar H. cunea larvae. the LD 50 for this virus (7.9 × 10 5 capsules/larva) was significantly greater than the LD 50 calculated for the H. cunea granulosis virus (7.06 × 10 4 capsules/larva) against the same instar of H. cunea . Time mortality studies demonstrated that the LT 50 values for the D. virginica granulosis were four to six times greater than for comparable dosages of H. cunea granulosis virus. Based on the mortality response of assayed H. cunea , it is possible to distinguish between the D. virginica granulosis virus and the H. cunea granulosis virus.

Two species of woolly bear caterpillars, Diacrisia virginica and Estigmene congrua, were shown by behavioural tests to prefer Petunia hybrida to five of nine common food-plants. Ingestion of Petunia causes acute illness from which most individuals recover. After recovery larvae no longer prefer Petunia. The potential value of food-aversion learning to polyphagous insects is discussed.

Measurements were made of the differences between sunflower and climbing hempweed leaves for development, fecundity and egg hatchability of Diacrisia casignetum Kollar. Developmental time and weight gains of sunflower-fed larvae were respectively longer and greater than those of hempweed-fed ones. The development time and weight gain, attributable to differences in host plants, were statistically heterogeneous (P < 0.05 − < 0.10). Relative fecundity and egg hatchability of sunflower reared insects were greater than those of hempweed reared ones, and these were also statistically heterogeneous (P < 0.1 and < 0.05, respectively). Hempweed leaves contained relatively high titres of phenols and low ratios of proteins to phenols. Ovaries were heavier in insects reared on sunflower than on hempweed, whereas the level of phenols incorporated into the ovary was higher in insects fed on hempweed than those on sunflower. The differences in these parameters may be due to variations in nutritional quality of these hosts and incorporation of ingested phenolic materials to ovary and insect biomass. RESUME Influence des plantes hotes sur le developpement, la fecondite et l'eclosion des oeufs de Diacrisia casignetum L'etude a porte sur l'evaluation de l'influence des feuilles de tournesol (Helianthus annuus) et de Mikana cordata sur le developpement, la fecondite et l'eclosion des oeufs de D. casignetum Kollaz. La duree de developpement et le gain de poids sur tournesol etaient plus importants que sur M. cordata. La duree de developpement etait statistiquement heterogene (P < 0.05), ce qui peut ětre du a des differences entre plantes. La fecondite et le taux d'eclosion chez les insectes eleves sur tournesol etaient plus eleves que ceux observes sur M. cordata, dont les resultats etaient aussi heterogenes (P < 0.1 et < 0.05 respectivement). Les feuilles de M. cordata contenaient des taux relativement eleves de phenols et des rapports proteines sur phenols bas. Tout ceci suggere que les differences observees sont attribuables a des variations dans la qualite nutritive de ces hotes et dans l'incorporation a la biomasse de l'insecte de materiaux phenologiques ingeres.

The ground-dwelling woolly bear caterpillar Diacrisia virginica occupies a habitat characterized by low-lying forbs, grasses, and sedges where it feeds on more than 100 species of plants. The short effective range of its visual and olfactory senses restricts to 1 cm or less the distance from which it can recognize plants. Caterpillars meander randomly and blunder into food plants. Because of the dense and complex vegetational texture of the habitat, the random locomotion in the field, and the omnivorous diet of the caterpillars, only a small proportion of time need be spent wandering (2%). More than 90% of the time is devoted to inactivity which represents postprandial and trail resting. Meal size is regulated by state of deprivation and is modified by the position of the plant in the hierarchy of acceptability. With increasing deprivation larvae become less finicky and therefore seldom experience acute starvation. The effectiveness of plants in sustaining survival and optimal growth of caterpillars is only grossly correlated with acceptability. The field behavior of D. virginica seems to be well described by the thermostatic model of feeding which predicts time budgeting for animals as a function of physiological and ecological parameters.

Effects of stand density and late-season defoliation by Mexican bean beetles, Epilachna varivestis Mulsant, on three yield components of beans were estimated from field studies conducted during 1983 and 1984 in four fields of pinto beans in northeastern Colorado. Number of beans per plant, mean weight of a bean, and mean weight of beans per plant were calculated for 100 samples per field, and regressed against three independent variables: plant density, percentage of defoliation, and density × defoliation interaction. Results of the analyses showed that plant density negatively affected number of beans per plant and weight of beans per plant, but not average weight of a bean. Responses were not linear; slope decreased at higher densities. Defoliation negatively affected all three yield variables. Average weight of a bean was linearly related to defoliation. Number of beans per plant and weight of beans per plant showed linear responses above a threshold level of defoliation. A piecewise regression model indicated that yields were not affected by defoliation until levels reached approximately 19% foliage loss. Laboratory consumption studies were conducted to determine age-specific damage potential for Mexican bean beetles and two occasional defoliators of pinto beans, saltmarsh caterpillars, Estigmene acrea (Drury), and yellow woollybears, Spilosoma virginica (F.). Insect consumption potentials and field studies of yield responses to defoliation were used to estimate threshold densities.

A BL trap was operated in 1970 in Craighead County, Arkansas, and results of catches were used as a basis for construction of curves to illustrate fluctuation and seasonal trend for 12 species of moths. The forage looper, Caenurgina crechtea (Cramer), was collected in the largest numbers and was followed by the claybacked cutworm, Agrotis gladiaria (Morrison); corn earworm, Heliothis zea (Boddie); dingy cutworm, Feltia subgothica (Haworth); armyworm, Pseudaletia unipuncta (Haworth); bristly cutworm, Lacinipolia renigera (Stephens); yellow woollybear, Diacrisia virginica (F.); variegated cutworm, Peridroma saucia (Hubner); black cutworm, A. ipsilon (Hufnagel); saltmarsh caterpillar, Estigmene acrea (Drury); cotton leafworm, Alabama argillacea (Hubner); and granulate cutworm, F. subterranea (F.). The claybacked cutworm, dingy cutworm, and cotton leafworm were collected after September 10, with distinct peaks in October. Most specimens of the variegated cutworm and bristly cutworm were trapped by late June. The armyworm, yellow woollybear, forage looper, black cutworm, and saltmarsh caterpillar were relatively active throughout the period from April 3 to November 13. The trapped male:female ratios were: corn earworm 8:5, saltmarsh caterpillar 4:1, and armyworm 1:1.

Laboratory applications of 4'-(3,3-dimethyl-l-triazeno) acetanilide (American Cyanamid CL-24055) to cotton plants limited leaf feeding and reduced the larval weights of the bollworm, Heliothis zea (Boddie); tobacco budworm, H. virescens (F.); cabbage looper, Trichoplusia ni (Hubner); yellow woollybear, Diacrisia virginica (F.); and cotton leafworm, Alabama argillacea (Hubner). Feeding damage by the cabbage looper was reduced 90% when larvae were placed on leaves 2 hr after 24 hours. Injection or topical applications of CL-24055 to bollworm larvae did not reduce larval feeding as much as foliage applications. In field-cage studies a 58% reduction occurred in populations of bollworm larvae after treatment with CL-24055. Also, in a field test with CL-24055, a 22% reduction occurred in squares and bolls damaged by Heliothis spp. Tobacco budworm larvae fed leaves treated with CL-24055 weighed less, whether or not the labial palpi were removed. The following materials caused no (A1%) reduction in tobacco budworm and cabbage looper larval feeding and weight: alpha- (3-phenylpropyl) piperonyl alcohol; phenacyl thiocyanate; N-sec- butyl- p -toluamide; p -(1,1,3,3-teracnetgyt-butyl) phenyl propionate; octyl m -toluate;4 (or5)-chloro- N-N -diethy 1-2-methylcyclohexanecarboxamide; N ,2,2-trimethy1-4',5'-(methylenedioxy)-3 (2-methylpropenyl)-2'-propylcyclopropanecarboxanilide; N -butylsuccinimide; 2-methyoxyethyl 4(or 5)-chloro-2-methylcyclohexanecarboxylate; calamus oil distillate fractions; imidazole; and the plant pigment quercetin (3,3', 4'5,7-pentahydroxyffavone).

Early 3rd instarDiacrisia obliqua Walk. larvae were treated with concentrations ofBacillus thuringiensis var.kurstaki (Dipel®) and the growth of treated larvae was assessed. All the doses reduced significantly the weight and survival of the insects (p

Curves showing the hourly and seasonal catches in traps equipped with black light lamps are given for 6 species of North Carolina insect pests: the army worm, Pseudaletia unipuncta (Haworth); the yellow-striped army worm, Prodenia ornithogalli Guenee; the black cutworm, Agrotis ipsilon (Hufnagel); the grape leaf skeletonizer, Harrisina americana (Guerin-Meneville); the yellow woollybear, Diacrisia virginica (F.); and the European corn borer, Ostrinia nubilalis (Hubner).

Sesquiterpene lactone glaucolide-A from Vernonia, incorporated in the rearing diets of five species of Lepidoptera, significantly reduced the rate of growth of larvae of the southern armyworm, Spodoptera eridania; fall armyworm, S. frugiperda; and yellowstriped armyworm, S. ornithogalli. Quantitative feeding tests demonstrated that decreased feeding levels and reduced growth resulted from ingestion of a sesquiterpene lactone. Ingestion of glaucolide-A increased the number of days to pupation in four of the species. In the southern armyworm, it significantly reduced pupal weight. Glaucolide-A decidedly reduced percentage of survival of southern and fall armyworms. Yellow woollybear, Diacrisia virginica, and cabbage looper, Trichoplusia ni, larvae were essentially uneffected by the ingestion of the sesquiterpene lactone. Sesquiterpene lactones adversely affect growth rate and survival of certain insects that feed upon plants containing them. They apparently function as defensive products, screening out a portion of the potential herbivores.