Naranga Aenescens Research Articles

Active behaviour of terrestrial caterpillars on the water surface.

Most butterfly and moth larvae (Lepidoptera) are terrestrial. When terrestrial caterpillars accidentally fall into water, they may drown or be preyed upon by aquatic predators before they can safely reach land. However, how terrestrial caterpillars escape aquatic environments and predators remains unclear. In July 2018, we observed a terrestrial caterpillar actively moving forward on the surface of a pond in Japan until it successfully reached the shore. To further investigate this behaviour in terrestrial caterpillars, we experimentally placed larvae of 13 moth species (four families) on a water surface under laboratory and field conditions. All caterpillars floated. Larvae of seven species moved forward on the water surface, whereas those of six species did not. A total of two types of behaviour were observed; in Dinumma deponens, Hypopyra vespertilio, Spirama retorta, Laelia coenosa, Lymantria dispar (all Erebidae), and Naranga aenescens (Noctuidae), larvae swung their bodies rapidly from side to side to propel themselves along the water surface (i.e., undulatory behaviour); in contrast, larvae of Acosmetia biguttula (Noctuidae) rapidly moved the abdomen (posterior segments) up and down for propulsion along the water surface (i.e., flick behaviour). Although thoracic legs were not used for undulatory and flick behaviour, rapid movements of the abdomen were used to propel caterpillars on the water surface. We also observed that undulatory and flick behaviour on the water surface aided caterpillars in escaping aquatic predators under field conditions. In addition, we investigated the relationship between body size and undulatory behaviour on the water surface in the erebid S. retorta under laboratory conditions. The frequency and speed of forward movement on the water surface increased with body length. Together, these results show that the rapid movement of elongated bodies results in forward propulsion on the water surface, allowing some terrestrial caterpillars to avoid drowning or aquatic predators. We further suggested potential factors related to morphology, host plant habitat, and defensive behaviour that may have led to the acquisition of aquatic behaviour in terrestrial caterpillars.

Resistance of transgenic rice events (rbcS:cry1Ac) against three lepidopteran rice pests

The transgenic rice expressing cry1Ac gene, which is linked to the rice rbcS promoter and its transit peptide sequence (tp), was highly resistant against all instars of Cnaphalocrocis medinalis (Guenetée) (Lepidoptera: Crambidae). In this study, we evaluated the larval mortality, behavior change, and field occurrence of three main rice pests, C. medinalis, Naranga aenescens (Moore) (Lepidoptera: Noctuidae), and Parnara guttata (Bremer & Grey) (Lepidoptera: Hesperiidae) in T4 generations of three Bt rice events (rbcS3:cry1Ac; 608102, 608104 and 608107) and non-Bt rice. All of the three Bt rice events were resistant to C. medinalis which showed significantly higher mortality for all instars compared to non-Bt rice. The resistance of Bt rice events against the larvae decreased gradually as the larvae developed. However, the survived larvae which ingested Bt rice events died eventually without further development. The resistance of three Bt rice events was investigated in the pot test, which was conducted with 3rd instars of C. medinalis, N. aenescens, and P. guttata, showed mortalities of over 70%. In behavioral assay, C. medinalis fed on the Bt rice events showed feeding avoidance and less leaf rolling behavior compared to that of the larvae fed on non-Bt rice. A 2-yr field survey conducted with larvae of C. medinalis and P. guttata also showed that the three Bt rice events significantly had lower damaged on leaves compared to that of non-Bt rice. Overall, the three Bt rice events were highly resistant to the larvae of lepidopteran target rice pests.

Severe Outbreak of Rice Green Semilooper, Naranga aenescens (Moore) (Lepidoptera: Noctuidae) along with Its Parasitoid Complex in Sub-Himalayan West Bengal, India

Severe outbreak of rice green semilooper Naranga aenescens Moore (Lepidoptera: Noctuidae: Eustrotiinae) in West Bengal, India is documented along with the first record of its primary parasitoid Cotesia ruficrus (Haliday) (Hymenoptera: Braconidae: Microgastrinae). Simultaneously two hyperparasitoids viz., Trichomalopsis apanteloctena (Crawford) (Pteromalidae) and Mesochorus sp. (Ichneumonidae) were also recorded. The population of rice green semilooper varied from 3.20 to 5.45 larvae per hill with the peak in the first fortnight of August, 2015. Percent parasitism of the larvae was as high as 94.00% recorded in the first fortnight of August with 77.50% as the mean.

Thermal effects on the development of Naranga aenescens Moore (Lepidoptera: Noctuidae)

Naranga aenescens Moore is an important insect pest found in rice paddy field. We investigated the development periods of N. aenescens egg, larva, pupa, and total immature insects at eight constant temperatures: 15.0°C, 17.5°C, 20.0°C, 22.5°C, 25.0°C, 27.5°C, 30.0°C, and 32.5°C. N. aenescens developed successfully from the egg stage to the adult stage at all the tested temperatures except 15.0°C. The developmental time of each life stage was significantly influenced by temperatures. The developmental rate of N. aenescens increased as the temperature increased from 15.0°C to 30.0°C but declined at 32.5°C, except in the pupa stage. The lower developmental threshold (LDT) and the thermal constant (K) was estimated using linear regression. The higher temperature threshold and the lower temperature threshold were calculated using two nonlinear functions. LDT and K from egg to adult emergence were 12.01°C and 330.84 degree days, respectively. The temperature range of N. aenescens from the lower developmental threshold to the higher developmental threshold using a performance model (24.03) was wider than that determined using the Sharpe–Schoolfield–Ikemoto model (19.77). Developmental completion of N. aenescens was described using a two-parameter Weibull distribution model. Adult emergence frequency of N. aenescens over a full range of constant temperatures was simulated using developmental rate functions and the Weibull function. Biological characteristics of N. aenescens populations from different geographic areas were discussed.

Identification and application of the sex pheromones of the rice green caterpillar Naranga aenescens in Korea

This study was carried out to investigate the optimum composition of sex pheromones for mate attraction in the rice green caterpillar Naranga aenescens, and to evaluate the effects of pheromone quantity, trap type, and trapping location on trapping success in Korean paddy fields. Mating rate of N. aenescens increased with age, with the highest mating rate 2days after emergence. The highest mating rate occurred within 1h after lights-off; mating pairs were not observed during the photophase. In electroantennogram (EAG) and gas chromatography with electroantennographic detection (GC–EAD) analysis, virgin female extracts had 2 EAD-active components. The mass spectra of the 2 distinct EAD-active components were identical to those of Z9-14:Ac and Z11-16:Ac. Additionally, Z9-16:Ac was identified in the extracts in gas chromatography–mass spectrometry (GC–MS) analysis. Wing traps with lures containing 1mg of a 2:1:4 mixture of Z9-14:Ac, Z9-16:Ac, and Z11-16:Ac was the most attractive to N. aenescens males. Pheromone-baited wing trapping, therefore, can be a simple and effective tool for monitoring N. aenescens populations.

Role of endogenous inhibitors on digestive amylolytic and proteolytic activities of a predatory hemipteran, Andrallus spinidens Fabricius

The role of endogenous inhibitors on digestive amylolytic and proteolytic activities of Andrallus spinidens Fabricius (Hemiptera: Pentatomidae) were studied by using extracted endogenous inhibitors from Pieris brassicae, Naranga aenescens, Chilo suppressalis, Ephestia kuehniella and Hyphantria cunea. The endogenous inhibitors from P. brassicae and N. aenescens had the most inhibitory effects on α-amylase of A. spinidens. General proteolytic activity in the mid-gut of A. spinidens was affected by incubation of the endogenous inhibitors from N. aenescens, H. cunea and P. brassicae, but no inhibitory effects were observed in case of C. suppressalis and E. kuehniella. Extracted inhibitors from C. suppressalis, E. kuehniella and N. aenescens significantly decreased trypsin- and chymotrypsin-like activities in the mid-gut of A. spinidens. All extracted inhibitors significantly decreased elastase-like activity of A. spinidens vs. control, except for C. suppressslis. Extracted inhibitors from all species significantly decreased cathepisns B and L activities but this was not significantly different in case of C. suppressalis. Endogenous inhibitors also affected amino- and carboxypeptidase activities in the mid-gut of A. spinidens. Digestive enzymes of A. spinidens are sensitive to endogenous inhibitors from some preys and this might be the reason that some species are more appropriate than others.

Control of Green Rice Caterpillar, Naranga aenescens, by Insecticidal Nursery Box Application

Control of Green Rice Caterpillar, <i>Naranga aenescens</i>, by Insecticidal Nursery Box Application

Biochemical characterization of α- and β-glucosidases in alimentary canal, salivary glands and haemolymph of the rice green caterpillar, Naranga aenescens M. (Lepidoptera: Noctuidae)

The biochemical properties of α- and β-glucosidase in salivary glands, alimentary canal and haemolymph of Naranga aenescens larvae, one of the most damaging pests of the rice crop in Iran, were investigated. The specific activity of α-glucosidases were 3.88, 2.74 and 1.58 μmol/min per mg protein in the alimentary canal, salivary glands and haemolymph of last instar larvae, respectively. The specific activity of β-glucosidases were 1.27, 0.077 and 0.414 μmol/min per mg protein in the alimentary canal, salivary glands and haemolymph of last instar larvae, respectively. The optimal pH for α-glucosidases were 6.0, 6.0–8.0 and 6.0 and the maximum activity for β-glucosidases were obtained at pH 6.0, 5.0–7.0 and 5.0 in alimentary canal, salivary glands and haemolymph, respectively. The optimum temperatures for β-glucosidases were determined at 55°C in alimentary canal, 35–45°C in salivary glands and 55°C in haemolymph, whereas the α-glucosidases reached their optimum at 45°C in all three tissues. Effect of metal ions on the activity of α- and β-glucosidases showed that K+ (20 mM) and Mg2+ (10 and 20 mM) increased N. aenescens α- and β-glucosidases activities from salivary glands, while Ca2+ increased α- and β-glucosidases activities in haemolymph. In the presence of Fe2+, Mn2+, Hg+ and Zn2+ (10, 20 mM) and Hg2+ (20 mM), these enzymes from all tissues were completely inactivated. K m values were estimated for the α-glucosidases as 3.96, 0.547 and 3.084 mM and for β-glucosidases as 1.93, 1.014 and 1.93 mM in the alimentary canal, salivary gland and haemolymph, respectively. The zymogram analyses of N. aenescens crude extracts indicated the presence of at least two isoforms for α-glucosidase and one isoform for β-glucosidase.

Role of Proteases in Extra-Oral Digestion of a Predatory Bug,Andrallus spinidens

Roles of salivary proteases in the extra-oral digestion of the predatory bug, Andrallus spinidens Fabricius (Hemiptera: Pentatomidae) were studied by using 2% azocasein as a general substrate and specific protease substrates, as well as synthetic and endogenous inhibitors. It was found that salivary glands of A. spinidens have two anterior, two lateral, and two posterior lobes. Azocasein was used to measure the activity of general proteases in the salivary glands using different buffer solutions. The enzyme had the highest activity at pH 8. General protease activity was highest at 40 °C and was stable for 6–16 hours. The use of specific substrates showed that trypsin-like, chymotrypsin-like, aminopeptidase, and carboxypeptidase are the active proteases present in salivary glands, by the maximum activity of trypsin-like protease in addition to their optimal pH between 8–9. Ca2+ and Mg2+ increased proteolytic activity about 216%, while other ions decreased it. Specific inhibitors including SBTI, PMSF, TLCK, and TPCK significantly decreased enzyme activity, as well as the specific inhibitors of methalloproteases including phenanthroline, EGTA, and TTHA. Extracted endogenous trypsin inhibitors extracted from potential prey, Chilo suppressalis, Naranga aenescens, Pieris brassicae, Hyphantria cunea, and Ephestia kuhniella, had different effects on trypsin-like protease activity of A. spinidens salivary glands. With the exception of C. suppressalis, the endogenous inhibitors significantly decreased enzyme activity in A. spinidens.

A trypsin‐like protease in rice green semi‐looper, Naranga aenescens moore (lepidoptera: Noctuidae): purification and characterization

The rice green semi looper, Naranga aenescens Moore (Lepidoptera: Noctuidae) causes severe damage to rice fields in Eastern Asia and Middle East. We demonstrate that two types of serine proteases are active in the midgut of the third instar larvae of N. aenescens, but trypsin-like proteases are considerably more active than chymotrypsin-like proteases. To develop better control strategies, purification and biochemical characterization of a major trypsin-like digestive protease from the midgut of the third instar larvae of N. aenescens was achieved by gel filtration and anion exchange chromatography. After the final purification step, the enzyme was purified 9.62-fold with a recovery of 16.1% and a specific activity of 4.12 U/mg protein and a molecular mass of approximately 88.5 kDa. Biochemical characterization indicated that the purified protease had highest activity at pH 10 and 30°C and was stable for up to 6 h under those conditions. Divalent cations, especially Ca2+, Mg2+, and Cu2+, increased the enzyme activity and synthetic inhibitors that target trypsin-like activity caused a significant reduction in caseinolytic activity. These data may be used to develop inhibitors that decrease the damage of N. aenescens to rice cultivars in the field.

Effect of multiple infestations from insect pests and other stresses on irrigated rice in the Philippines: I. Damage functions

Artificial infestation methods were employed to generate damage function graphs for guilds of three rice insect pests. In the vegetative stage, infestation of whorl maggot (Hydrellia philippina Ferino) and defoliators (a mixed population of Naranga aenescens Moore and Rivula atimeta [Swinhoe]) was applied as a combined or single pest attack. Infestation of yellow stemborer (Scirpophaga incertulas [Walker]) and leaffolder (Cnaphalocrocis medinalis [Guenée]) each were infested in one or two crop growth stages. Combinations of three stresses (four N application rates, solar radiation from the wet or dry season, and/or the presence or absence of weeds) were applied to each guild to develop more holistic economic injury levels (EILs). Slopes on the linear portion of damage curves of each pest guild became steeper with each additional stress applied, whether from multiple insect pest attack, low N, low solar radiation, or weeds. EILs can be developed by pest managers from the graphs of the damage functions for the variables quantified in this study.

토양에서 분리한 곤충병원성세균 Bacillus thuringiensis 의 혹명나방과 벼애나방에 대한 실내살충효과검정 및 생물학적 특성에 미치는 영향

벼에 발생하여 잎을 가해하여 피해를 주는 혹명나방(Cnaphalocrosis medinalis)과 벼애나방(Naranga aenescens)의 곤충병원성미생물을 이용한 친환경적 방제를 위해, 국내토양에서 분리된 Bacillus thuringiensis 균주들을 대상으로 생물검정을 수행하였다. 실험에 이용한 Bt 53균주 중, 약 18개 균주가 혹명나방에 90% 이상의 살충률을 나타내었고, 13개 균주가 벼애나방에 살충활성을 보였는데, 두 종 모두에 90% 이상의 살충률을 보이는 균주도 CAB141균주를 비롯해 11균주나 확인되었다. 이러한 균주들은 혹명나방에 대한 실내방제실험결과, 96%이상의 방제효과를 나타내기도 하였다. 또한 Bt 포자현탁액에 노출된 유충의 용화율, 용길이, 우화율이 감소되는 경향이 나타났는데, 혹명나방의 경우, 번데기 길이에서도 정상개체와 처리 후 생존개체가 현저한 차이를 나타내었다. For biological control of larva of Cnaphalocrocis medinalis and Naranga aenescens do considerable damage to crops by folding and scraping the leaf tissue of rice, a large number of Bacillus thuringiensis isolates have been obtained from soil samples in Korea and the pesticidal activity was assayed against two insect pest species described above. Among 53 Bt isolates tested in bioassay, 18 and 13 isolates showed over 90% mortality against C. medinalis and N. aenescens, respectively. Some isolates (11 isolates including CAB141) presented dual activity against C. medinalis and N. aenescens. These isolates showed over 96% control effect in pest control in laboratory against larvae of C. medinalis. Also, it was investigated that pupation, pupal length, and adult emergence of larvae exposed to Bt suspension decreased. Especially, the pupal length of C. medinalis after being fed corn seedling leaves treated Bt suspension for 10 days, were much smaller than that of control.

Evaluation of action thresholds for chronic rice insect pests in the Philippines: II. Whorl maggot and defoliators

Action thresholds as insecticide decision tools were developed and evaluated against chronic vegetative stage insect pests of irrigated transplanted rice in the Philippines: whorl maggot Hydrellia philippina Ferino (Diptera: Ephydridae( and two lepidopterous defoliators, Naranga aenescens Moore and Rivula atimeta (Swinhoe( (Lepidoptera: Noctuidae(. Through an iterative process, new threshold characters and insecticide technologies were evaluated at four sites (categorized as high and low pest density sites( over a 13-year period with the objectives of minimizing insecticide usage and maximizing farmer adoption. Characters were evaluated as to their ability to predict significant pest densities and yield loss. Significant differences occurred between high and low pest density sites among the best characters and monitoring methods for both pests. Earlier-planted fields were used as a forecasting tool, showing best results in the high pest density sites. Overall, most threshold characters performed well but the insecticide response was poor. Insecticide control was better with some threshold characters than others due to better timing. Seedling root soak with isofenphos was more effective than granules or foliar sprays against whorl maggot but required a decision before planting. Foliar sprays were most effective if applied twice (2 and 7 days after transplanting(. The best performing characters for whorl maggot were 1 – 2 eggs/hill for the low pest density sites and 15 – 30% damaged leaves in earlier planted fields in high density sites. The best performing characters for defoliators were 10% damaged leaves monitored in earlier planted fields for high density sites and 10% damaged leaves in low density sites. Carbaryl was the most effective insecticide spray against defoliators that combined performance and relative safety.

Effect of plant age, larval age, and fertilizer treatment on resistance of a cry1Ab-transformed aromatic rice to lepidopterous stem borers and foliage feeders.

The resistance of vegetative, booting, and flowering stage plants of a variety of an aromatic rice, Oryza sativa L., transformed with a Bacillus thuringiensis Berliner cry1Ab gene under control of the maize phosphoenolpyruvate carboxylase (PEPC) promoter was evaluated against four lepidopterous rice pests--the stem borers Chilo suppressalis (Walker) (Lepidoptera: Crambidae) and Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae), and the foliage feeders Cnaphalocrocis medinalis Guenée (Lepidoptera: Pyralidae) and Naranga aenescens Moore (Lepidoptera: Noctuidae). Plants of the cry1Ab-transformed line (no. 827) were more resistant to young larvae of S. incertulas, C. suppressalis, and C. medinalis than control plants at the vegetative stage but not at the flowering stage. Survival of 10-d-old stem borer larvae did not differ on cry1Ab plants and control plants at either the vegetative or flowering stage, but the development of 10-d-old C. suppressalis larvae was retarded on the vegetative stage cry1Ab plants. Immunological analysis also showed an apparent decline in Cry1Ab titer in leaf blades and leaf sheaths at the reproductive stage. In experiments comparing three fertilizer treatments (NPK, PK, and none), there was a significant interaction between fertilizer treatment and variety on larval survival only in whole-plant assays at booting stage with C. suppressalis. On cry1Ab plants, larval survival did not differ significantly among the three fertilizer levels, whereas on control plants survival was highest with the NPK treatment. cry1Ab plants tested at the sixth and seventh generations after transformation were more resistant than control plants to N. aenescens and C. suppressalis, respectively, suggesting that gene silencing will not occur in line 827. The results of the experiments are discussed in terms of resistance management for B. thuringiensis toxins in rice.

Acceptance of eggs ofRivula atimeta, Naranga aenescens [Lep.: Noctuidae] andHydrellia philippina [Dipt.: Ephydridae] by insect predators on rice

Eight insect predators common in the rice ecosystem in the Philippines were compared in the laboratory on their ability as to feed on the eggs of green hairy caterpillar,Rivula atimeta Swinhoe. A ranking, based on feeding rates was made:Metioche vittaticollis (Stal) (Gryllidae) was the most voracious predator, followed byAnaxipha longipennis (Serville)(Gryllidae), Ophionea nigrofasciata (Schmidt-Goebel)(Carabidae), Micraspis nr.crocea (Mulsant) (Coccinellidae) andConocephalus longipennis (de Haan) (Tettigoniidae). Also the smallCyrtorhinus lividipennis Reuter (Miridae), readily fed upon the eggs.Paederus fuscipes Curtis (Staphilinidae) andCoccinella repanda (Thunberg) (Coccinellidae) fed to a very limited extent.Metioche vittaticollis andCyrtorhinus lividipennis were also tested on eggs of green semilooper,Naranga aenescens Moore, and rice whorl maggot,Hydrellia philippina Ferino. The feeding rate ofM. vittaticollis was similar on the 3 different preys, butC. lividipennis had a higher feeding rate onN. aenescens eggs.

Comparison of Catches between Sex Pheromone Trap and Light Trap for the Rice Green Caterpillar, Naranga aenescens Moore

Comparison of Catches between Sex Pheromone Trap and Light Trap for the Rice Green Caterpillar, <I>Naranga aenescens</I> Moore

Sex Pheromone of the Rice Green Caterpillar: Chemical Identification of Three Components and Field Tests with Synthetic Pheromones

The sex pheromone of the rice green caterpillar, Naranga aenescens Moor, was presumed to be a mixture of some unsaturated acetates using electroantennogram technique. Abdominal tips of virgin females were shown to contain (Z)-9-tetradecenyl acetate (compound I), (Z)-9-hexadecenyl acetate (compound II) and (Z)-11-hexadecenyl acetate (compound III) in a ratio of 1:1:4, respectively. These synthetic three compounds were individually active on the male antenna but only the mixture of the three compounds attracted the male moths in a field. Field traps containing the three compounds in a ratio of 1:1:4 (1 mg/rubber septum) consistently attracted more males than traps baited with two unmated females.

Sex pheromone of the rice green caterpillar: Chemical identification of three components and field tests with synthetic pheromones.

The sex pheromone of the rice green caterpillar, Naranga aenescens Moor, was presumed to be a mixture of some unsaturated acetates using electroantennogram technique. Abdominal tips of virgin females were shown to contain (Z)-9-tetradecenyl acetate (compound I), (Z)-9-hexadecenyl acetate (compound 11) and (Z)-11-hexadecenyl acetate (compound III) in a ratio of 1:1:4, respectively. These synthetic three compounds were individually active on the male antenna but only the mixture of the three compounds attracted the male moths in a field. Field traps containing the three compounds in a ratio of 1:1:4 (1mg/rubber septum) consistently attracted more males than traps baited with two unmated females.