Autographa Nigrisigna Research Articles

Seasonal Incidence of Major Insect Pest of Chickpea and their Natural Enemies in Vindhaya Region of Madhya Pradesh

Field experiment carried out at the Entomology Instructional Farm, JNKVV-College of Agriculture Rewa, MP during rabi season 2018-19 revealed that incidence of the chickpea pod borer Helicoverpa armigera. Population range of pod borer during different weather weeks varied between 0.30 and 1.89 larvae/mrl (April 2nd week and March 2nd week respectively). Peak larval population of Helicoverpa armigera was recorded in 2nd week of March (11 standard weeks). A weak negative correlation was observed with the maximum relative humidity and minimum relative humidity correlation, -0.172 and -0.595 respectively and a non significant positive correlation with maximum temperature, minimum temperature and rainfall. The respective r was found to be 0.306, 0.391 and 0.269. In district Rewa, MP, India the insect-pests of chickpea and their natural enemies during rabi the total seven species was recorded in Chickpea in which six pests minor in nature and one major pest Chickpea pod borer (Helicoverpa armigera). Termite (Odontotermes obesus Ram.), White grub (Holotrichia consanguinea Bl.), Black aphid (Aphis craccivora Koch), Grasshopper (Chrotogonus trachypterus Blan.), Semilooper (Autographa nigrisigna L.), Cut worm (Agrotis ipsilon Huf.) are minor in nature. Seven natural enemies found during field investigation i.e. lady bird beetle (Chilomenes sexmaculata Fab.), lady bird beetle (Coccinella septempunctata L.), Praying mantis (Mantis religiosa), Dragon fly (Crocothemis servilia Drury), Campoletis parasitoid (Campoletis chlorideae Uch.), Indian mynah (Acridotheris tristis L.), King crow (Dicrurus macrocerus Vie.) in chickpea observed in low to medium population on the crop and to help in reduction of pest population.

Autographa nigrisigna (beet worm)

This datasheet on Autographa nigrisigna covers Identity, Overview, Distribution, Hosts/Species Affected, Diagnosis, Biology & Ecology, Natural Enemies, Impacts, Prevention/Control, Further Information.

Perception of Heterospecific Sex Pheromone Causes Less Effective Mating Disruption in the Beet Semilooper, Autographa nigrisigna (Lepidoptera: Noctuidae).

Confuser® V is a pheromone-based mating disruptant designed to reduce damage caused by seven species of moth pests, including the beet semilooper, Autographa nigrisigna (Lepidoptera: Noctuidae). Eggs and larvae of A. nigrisigna are often found in fields treated with Confuser® V, suggesting that some components in the Confuser® V blend may have adverse effects on the efficacy of mating disruption of this species. Therefore, we examined whether A. nigrisigna perceives heterospecific pheromone components in the Confuser® V blend and delineated the roles of these components with respect to attraction and communication disruption. We found that several heterospecific pheromone components in the Confuser® V blend were perceived by male A. nigrisigna, and the addition of these components to the pheromone blend of A. nigrisigna reduced the attraction of males in the field, and tended to reduce the efficacy of mating disruption in cage bioassays.

Morphology of egg and larva of the semi-looper Autographa nigrisigna (Walker) (Lepidoptera: Noctuidae: Plusiinae)

The semi-looper Autographa nigrisigna (Walker) is a polyphagous pest in Plusiinae (Lepidoptera: Noctuidae). However, the egg and larval morphologies have not been studied in detail to date. Here the eggs and larvae of A. nigrisigna were investigated using light and scanning electron microscopy. The egg is domed and is of an upright type, with two or three micropyles at the top and vertical ribs on the chorion. The micropyles are surrounded by a rosette-like pattern of radiating ribs. The eruciform larva possesses three pairs of thoracic legs and three pairs of abdominal prolegs each on A5, A6, and A10, the most remarkable larval character of Plusiinae. The crochets are uniordinal in a mesal penellipse. In chaetotaxy, SV2 is present on abdominal segments I–IV and X, but is absent on other segments. The roles of egg and larval characters in taxonomic and phylogenetic analyses are briefly discussed.

Two year field study to evaluate the efficacy of Mamestra brassicae nucleopolyhedrovirus combined with proteins derived from Xestia c-nigrum granulovirus.

Japan has only three registered baculovirus biopesticides despite its long history of studies on insect viruses. High production cost is one of the main hindrances for practical use of baculoviruses. Enhancement of insecticidal effect is one possible way to overcome this problem, so there have been many attempts to develop additives for baculoviruses. We found that alkaline soluble proteins of capsules (GVPs) of Xestia c-nigrum granulovirus can increase infectivity of some viruses including Mamestra brassicae nucleopolyhedrovirus (MabrNPV), and previously reported that MabrNPV mixed with GVPs was highly infectious to three important noctuid pests of vegetables in the following order, Helicoverpa armigera, M. brassicae, and Autographa nigrisigna. In this study, small-plot experiments were performed to assess concentrations of MabrNPV and GVPs at three cabbage fields and a broccoli field for the control of M. brassicae. In the first experiment, addition of GVPs (10 µg/mL) to MabrNPV at 106 OBs/mL resulted in a significant increase in NPV infection (from 53% to 66%). In the second experiment, the enhancing effect of GVP on NPV infection was confirmed at 10-times lower concentrations of MabrNPV. In the third and fourth experiments, a 50% reduction in GVPs (from 10 µg/mL to 5 µg/mL) did not result in a lowering of infectivity of the formulations containing MabrNPV at 105 OBs/mL. These results indicate that GVPs are promising additives for virus insecticides.

Effects of manipulated density of the wolf spider, Pardosa astrigera (Araneae: Lycosidae), on pest populations and cabbage yield: a field enclosure experiment

We manipulated the density of the wolf spider, Pardosa astrigera L. Koch in enclosed cabbage plots (2 × 2 m) to assess the impact on the herbivore density and crop yield. P. astrigera was introduced to half of the enclosures at densities of 25 and 50 individuals/m2 in the spring and autumn experiments, respectively; spiders were removed from other enclosures. The results indicated that P. astrigera significantly suppressed the densities of the diamondback moth, Plutella xylostella (L.), in the spring, and the green peach aphid, Myzus persicae (Sulzer), in the autumn experiments. The cabbage yield did not increase, despite the suppression of these herbivores. P. astrigera had no impact on three other lepidopteran species: Pieris rapae crucivora Boisduval, Autographa nigrisigna (Walker), and Mamestra brassicae (L.). The number of spiders increased by 23 % but decreased by 62 % at the end of the spring and autumn experiments, respectively, compared with the initial numbers introduced. Our results show that wolf spiders (Lycosidae) would be effective biocontrol agents of certain herbivore species if spiders abundantly occur early in the crop season and remain stable throughout the season. However, further investigations are required to determine the effect of spiders on the crop yield.

Laboratory Evaluation of the Flight Ability of Female <I>Autographa nigrisigna</I> (Lepidoptera: Noctuidae), Measured by Actograph and Flight Mill

Autographa nigrisigna (Lepidoptera: Noctuidae) is the target species of the mating disruptant for vegetables, Confuser V. However, emergence of A. nigrisigna does not decrease in the Confuser V treated vegetable fields. As one of the reasons for this phenomenon, migration of mated females into the Confuser V treated area were considered. Thus, we studied the flight ability of female A. nigrisigna by using computer-interfaced actograph and flight mill devices. Flight measurements for mated and unmated individuals 4- to 6-d-old were recorded for 24 h. The results of the actograph assay revealed that mated females moved more actively than unmated females, possibly because of their oviposition behavior. Both the flight duration and flight range, which were measured by the flight mill device, decreased continuously with age and did not show a significant difference between mated and unmated females through the ages from 4 to 6 d. This result indicates that mating status did not directly affect the flight duration or range. From our experiments, it was suggested that females maintain physical energy after mating at the same level as before mating and then mated females locomote more actively around the host plants for oviposition. These speculations are discussed in relation to the control of A. nigrisigna by mating disruption.

Seasonal parasitism and biological characteristics of Habrobracon hebetor (Hymenoptera: Braconidae) – a potential larval ectoparasitoid of Helicoverpa armigera (Lepidoptera: Noctuidae) in a chickpea ecosystem

Seasonal parasitism of Habrobracon hebetor (Say) on Helicoverpa armigera (Hübner) in chickpea was studied for three consecutive years. Parasitism by H. hebetor on larvae of H. armigera reached 12.3%. The parasitoid maintained reproductive activity on H. armigera from February to April coinciding with pod formation and maturation stages of the crop. In laboratory assays, we investigated the suitability of larval instars of H. armigera to the parasitoid H. hebetor. This parasitoid attacked third to sixth instars, though fourth and fifth instar larvae were found most suitable with 100% parasitism and development to adults. Parasitoid developmental time was longest in fifth instar (9.1 days) compared to other instars (8.1–8.9 days). Fifth instar larvae resulted in highest numbers of cocoons and adult emergence. In addition, suitability of seven lepidopteran species to H. hebetor was investigated. Corcyra cephalonica, Galleria mellonella and H. armigera were the most suitable hosts with 100% parasitism and development to adults. It was followed by Maruca vitrata and Autographa nigrisigna with 60–76.7% and 40–70% parasitism and parasitoid developmental success, respectively. Though there was 23.3% parasitism, there was no parasitoid development in Spodoptera litura. No parasitism was recorded in Spilarctia obliqua. Development of H. hebetor was most rapid in C. cephalonica (8.7 days), and longest in G. mellonella (9.3 days). Parasitoids that developed on these hosts resulted in highest numbers of cocoons and adult emergence. The parasitoid could be exploited for the biological control of H. armigera in a chickpea ecosystem.

Application of molecular techniques to identification of three plusiine species, Autographa nigrisigna, Macdunnoughia confusa, and Thysanoplusia intermixta (Lepidoptera: Noctuidae), found in integrated pest management lettuce fields in Japan.

Three plusiine species, Autographa nigrisigna, Macdunnoughia confusa, and Thysanoplusia intermixta (Lepidoptera: Noctuidae), are commonly found together in lettuce, Lactuca sativa L., fields in Japan. Given the marked morphological similarities between these species and the difficulty associated with discriminating between them using only visual cues, we used multiplex polymerase chain reaction (PCR) assay to distinguish between the three target species. Multiplex PCR uses four primers to simultaneously amplify a specific region of the mitochondrial DNA and produce species-specific banding patterns. The stringency of the method was tested using specimens of different sex, location, and developmental stage, and consistent results were obtained for all samples. Indeed, our method has the potential to clarify the species structure of plusiine species in lettuce fields.

Enhancing effect of proteins derived from Xestia c-nigrum granulovirus on Mamestra brassicae nucleopolyhedrovirus infection in larvae of Autographa nigrisigna (Lepidoptera: Noctuidae) on cabbage

The insecticidal effect of Mamestra brassicae nucleopolyhedrovirus (MabrNPV) and the enhancing activity of proteins derived from occlusion bodies (OBs) of Xestia c-nigrum granulovirus (GVPs) on the infectivity of MabrNPV were evaluated in a bioassay with second-instar larvae of Autographa nigrisigna (Walker) fed virus-applied cabbage plants. The lethal concentrations of MabrNPV achieving 50 and 95% mortality for A. nigrisigna were estimated to be 1.4 × 105 and 3.1 × 106 OBs/ml, respectively. When larvae were fed cabbage plants treated with MabrNPV and various concentrations of GVPs, the requisite concentration of GVPs achieving 95% mortality of A. nigrisigna was estimated to be 26.2–138.8 μg/ml in combination with 104 OBs/ml MabrNPV and 8.46–24.09 μg/ml with 105 OBs/ml MabrNPV. Increases in the concentration of MabrNPV or GVPs caused larval death at younger instars. A. nigrisigna has lower susceptibility to MabrNPV than M. brassicae and Helicoverpa armigera reported in Mukawa and Goto (J Econ Entomol 103:257–264, 2010). We estimated that the requisite concentration of MabrNPV for the control of A. nigrisigna was 105 OBs/ml, which is a tenfold higher concentration than that for M. brassicae and H. armigera, with the increase achieved by adding 10 μg/ml GVPs.

Cuticular encystment of Autographa nigrisigna eggs by epidermal cell migration

It was previously established that Autographa nigrisigna loopers form cuticular cysts at the dorsal site of the 9th (penultimate) abdominal segment after parasitization by the solitary endoparasitoid Campoletis chlorideae and get rid of the parasitoid egg with the old cuticle at ecdysis. The cuticular cyst consists of a space between the old cuticle and new cuticle formed by the epidermis to enclose the parasitoid egg. The fact that A. nigrisigna loopers exclude the oviposited egg from the hemocoel using a cuticular cyst raises the question how the parasitoid egg passes through the epidermis. To exclude the endoparasitoid eggs from the hemocoel, the epidermis is required to move the location of the parasitoid egg. In the current study, we investigated the morphological process of cuticular cyst formation. First, the oviposited egg drifted to the 9th abdominal segment located at the open end of the dorsal vessel as a result of force generated by the hemolymph current from the oviposition site, and formed contacts with the integument containing the fat body (FB). The epidermis, in contact with the egg, then began to move along with the basement membrane formed on the surface of the FB, and settled under the egg, thus altering its location. This inversion was duplicated in vitro using integument from the 9th abdominal segment when parasitoid eggs were inserted between the epidermis and FB. When the integument, without the FB, was incubated on an agar plate, the epidermal cells migrated on the plate. Integument without eggs showed no signs of migration from their original sites. When the actin polymerization inhibitor latrunculin B was added to the cultures, the epidermal cells remained in their original location.

Agrobacterium-mediated transformation of spinach (Spinacia oleracea) with Bacillus thuringiensis cry1Ac gene for resistance against two common vegetable pests

Agrobacterium-mediated genetic transformation was applied to produce transgenic plants of spinach (Spinacia oleracea) resistant to 2 pest species, Trichoplusia ni and Autographa nigrisigna. Leaf segments from in vitro spinach plants of cultivar 'Glory' were co-cultivated with A. tumefaciens strain EHA105, which harbored the plasmid pBE2111FMB containing a synthetic cry1Ac gene encoding an insecticidal crystal protein of Bacillus thuringiensis, and neomycin phosphotransferase II and bialaphos resistance genes as selectable marker genes. Kanamycin (Km)-resistant calluses were obtained from co-cultivated leaf segments 1 month after selection on 2.5 g l � 1 gellan gum-solidified MS medium containing 3 0gl � 1 sucrose, 0.5 mg l � 1 2,4-dichlorophenoxyacetic acid (2,4-D), 2 mg l � 1 kinetin, 100 mg l � 1 Km and 20 mg l � 1 meropenem trihydrate. Regeneration of adventitious shoots from Km-resistant calluses was performed on 2.5 g l � 1 gellan gum-solidified MS medium containing 30 g l � 1 sucrose, 0.01 mg l � 1 2,4-D, 1 mg l � 1 kinetin, 1 mg l � 1 gibberellic acid, 100 mg l � 1 Km and 10 mg l � 1 meropenem trihydrate at 14°C. PCR and Southern blot analyses of genomic DNA isolated from T1 plants confirmed the successful integration of T-DNA into the plant genome. Expression of Cry1Ac protein was confirmed in leaves of transgenic plants by Western blot analysis. Insect bioassays against T. ni and A. nigrisigna performed with T1 plants showed more than 93.3% insect mortality within 1 week. These results suggest that the cry1Ac gene was effectively expressed in spinach.

Autographa nigrisigna looper (Lepidoptera: Noctuidae) excludes parasitoid egg using cuticular encystment induced by parasitoid ovarian fluid

Autographa nigrisigna (Lepidoptera: Noctuidae) loopers form cuticular cysts on the dorsal site of the penultimate segment by parasitization of endoparasitoid Campoletis chlorideae (Hymenoptera: Ichneumonidae) and interrupt successful parasitization by excluding the parasitoid egg and larva in the hemocoel into the cyst. This study elucidated for the first time the difference in the exclusion rates with host age at the time of parasitization. All parasitized host loopers of D1L1 (Day 1, 1st instars) and D0L2 formed cuticular cysts and nearly 70% could exclude parasitoid eggs successfully; however, the number of loopers that could form cuticular cysts decreased with host aging at the time of parasitization. To elucidate the difference between the encapsulation system and cuticular encystment, it was examined whether the substances encapsulated are excluded by cuticular encystment. A small piece of antenna the same size as an egg used as a biotic foreign substance was absolutely encapsulated and was not excluded by encystment. Further, it was clarified whether parasitoid eggs with a different surface were encapsulated or excluded by cuticular encystment with or without ovarian fluid. UV eggs (with an intact surface and development ceased by UV treatment) were hard to encapsulate, but were excluded with encystment. Plasma eggs with a degenerate surface (treated with heating for 5 min at 60°C after 10-min immersion in plasma of Pseudaletia separata) were encapsulated and not excluded by cuticular encystment, although ovarian fluid increased the cyst formation rate. These results show that cuticular encystment functions to exclude parasitoid eggs incapable of encapsulation.

Cuticular Encystment in Larvae of Plusiinae Looper (Lepidoptera: Noctuidae) Parasitized by the Gregarious Endoparasitoid <I>Cotesia glomerata</I>

Abstract Lepidopteran larvae can exclude some organelles that have invaded the hemocoel by defense systems such as phagocytosis, encapsulation, and nodule formation. However, Plusiinae loopers have another system that can exclude organelles such as endoparasitoids by forming a cyst on the penultimate segment, i.e., cuticular encystment. In this study, we examined whether cuticular encystment is common in six species of Plusiinae loopers [Autographa nigrisigna Walker, Anadevidia peponis F., Trichoplusia ni (Hubner), Acanthoplusia agnata Staudinger, Erythroplusia rutilifrons Walker, and Trichoplusia intermixta Warren) from the first to the fourth stadia. Loopers were parasitized artificially by the gregarious endoparasitoid Cotesia glomerata L. Different rates of cuticular cyst formation were shown among species. More than one-half of the loopers formed a cuticular cyst in all species except T. intermixta. A. nigrisigna and A. peponis, in particular, formed >80% cysts in the first to third instars. However,...

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In general, plusiine moths actively begin flying from dusk and feeding and calling activities have been clearly discussed in many reports. We examined daily behaviors, specifically, flight, feeding and calling activities of the plusiine moths, Autographa nigrisigna, Thysanoplusia intermixta, Ctenoplusia agnata and Chrysodeixis eriosoma, which are major pests of various commercial crops in the Kanto region of Japan. Daily flight activities were tested with an actograph system in the laboratory. The insects showed pronounced flight activity soon after the lights were turned off, during darkness and after the lights were turned on. Of specific interest is that during darkness, C. eriosoma showed high flight activity earlier than the other three species. We also observed daily feeding and calling activities, and found these two activities were synchronized with flight activity. We conclude that patterns of calling and associated flights are not the same for all plusiine species although most adults of the Plusiinae fly actively during darkness.

Comparison of pheromone trap types for monitoring Autographa nigrisigna (Walker) and Trichoplusia ni (Hubner) (Lepidoptera: Noctuidae, Plusiinae) in cabbage fields.

Comparison of pheromone trap types for monitoring Autographa nigrisigna (Walker) and Trichoplusia ni (Hubner) (Lepidoptera: Noctuidae, Plusiinae) in cabbage fields.

Relation between plant density and arthropod density in cabbage fields

AbstractThe relationship between plant density and the abundance of arthropods was examined by planting cabbages in four densities (0.25, 1, 4, or 8 plants per square meter). Four herbivorous species were examined: the small white butterfly Pieris rapae crucivora Boisduval, the diamondback moth Plutella xylostella (Linnaeus), the beet semi‐looper Autographa nigrisigna (Walker), and the green peach aphid Myzus persicae (Sulzer). The number of spiders and the number of eggs of syrphid flies were also examined. The number of individuals per unit ground area increased curvilinearly with increasing plant density for most arthropods. To clarify the mechanism causing such a curvilinear increase, the oviposition behavior of Pieris rapae crucivora was examined. The oviposition process of a female was divided into three components: (1) entering the field, (2) alighting on a plant to bend her abdomen, and (3) attaching an egg on the leaf. The first and the second components curvilinearly increased with increasing plant density, while the third component was not influenced by the plant density. The analysis of the flight path of P. rapae crucivora indicated that the curvilinear increase in the frequency of abdominal bending behaviors occurs since a female flies at least about 1.3 m between successive abdominal bending behaviors, irrespective of the plant density, when the plant density is sufficiently high.

Effects of plant density on the survival rate of cabbage pests

AbstractThe population density of herbivores depends on the spatial scale as well as the temporal scale. In a small‐scale, short‐term experiment, the number of individuals entering from the surrounding area will be most influential in determining the herbivore density. In large‐scale, long‐term experiments, however, the density of herbivores will rather be influenced by the survival rate of individuals inside the field because most of the herbivorous population derives from the parents that developed inside the field. If we want to predict the large‐scale long‐term density of herbivores, therefore, emphasis should be placed on the estimation of survival rate. To elucidate the effects of plant density on the large‐scale long‐term abundance of cabbage pests, we examined the survival rates of three lepidopterous pests, the small white butterfly Pieris rapae crucivora Boisduval (Pieridae), the beet semi‐looper Autographa nigrisigna (Walker) (Noctuidae), and the diamondback moth Plutella xylostella (Linnaeus) (Yponomeutidae) under two levels of plant spacing (sparse plot, 2 m × 2 m interval; dense plot, 0.5 m × 0.5 m interval). The experiment with four blocks was repeated in two seasons. The number of eggs per plant was larger in the sparse plots than in the dense plots for all species. The survival rate of eggs and larvae, on the contrary, was lower in the sparse plots than in the dense plots. The lower survival rate of eggs in the sparse plots was mainly caused by the density dependency, while the lower survival rate of larvae in the sparse plots was mainly caused by the direct effects of plant density. It was thus suggested that the density of herbivores may become lower in the sparsely planted field in the long run because of the higher mortality of larvae.

Control of Autographa nigrisigna (Walker) by the Confusion Method Using Its Sex Pheromone

Control of <i>Autographa nigrisigna</i> (Walker) by the Confusion Method Using Its Sex Pheromone

北海道におけるガンマキンウワバおよびタマナギンウワバの寄生蜂

Two Braconid species (Cotesia plutellae, Microplitis tuberculifer), two Ichneumonid species (Diadegma sp., Campoletis sp.), and one Encyrtid species (Copidosoma floridanum) of parasitic wasps of Autographa gamma and Autographa nigrisigna were found in Hokkaido, Japan