Rice Moth Corcyra Cephalonica Research Articles

Cadmium triggers hormesis in rice moth Corcyra cephalonica but different effects on two Trichogramma egg parasitoids

Cadmium triggers hormesis in rice moth Corcyra cephalonica but different effects on two Trichogramma egg parasitoids

Impact of Essential Oils on Biological Traits of <i>Trichogramma chilonis</i> Ishii

Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) reared on factious host rice moth Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) is an egg parasitoid on lepidopteran pests. The essential oils, viz., ajowan Trachyspermum ammi, betel Piper betle, and sweet basil Ocimum basilicum and neem oil were assessed for their toxicity and biological traits like parasitism and emergence on T. chilonis. Among the EOs tested, T. ammi caused highest toxicity to T. chilonis (LC50 0.316 ppm) followed by P. betle (LC50 0.567 ppm). At sublethal dose, they had an impact on parasitism and adult emergence of T. chilonis. Whilst O. basilicum and neem oil were relatively safe at sublethal doses to T. chilonis. This study highlights the need to maintain a waiting period before the release of T. chilonis in EOs treated substrates.

COMPARISON OF DIFFERENT DIETS ON BIOLOGY OF CORCYRA CEPHALONICA (STAINTON) UNDER LABORATORY CONDITION

The study aimed to evaluate different rearing media for mass production of rice moth Corcyra cephalonica Stainton (Lepidoptera: Pyralidae), an important host insect for several bio-control agents. The development and reproductive performance of C. cephalonica was evaluated on six different combinations of rearing media containing maize, wheat, rice, jowar, ragi, sugar and groundnut. Results showed that the larval period, pupal period, adult emergence fecundity, adult longevity and fecundity were highest and true generation time was shortest in Diet VI (Wheat, yeast, groundnut). Hence, Diet VI is the most suitable rearing media for mass production of C. cephalonica.

Toxicity, Ovipositional Behaviour and Electrophysiological Response of Rice Moth <i>Corcyra cephalonica</i> (Stainton) Adults to Essential Oils

Rice moth Corcyra cephalonica (Stainton) is a serious pest on storage commodities. The management of C. cephalonica relies on the use of chemical pesticides. Insecticide resistance and its effect on nontarget demand for compounds that are clean, and green. Essential oils (EOs) viz., Trachyspermum ammi (Ajowan), Piper betle (betel), Eucalyptus citriodora (citridora), Cymbopogan nardus (citronella), Pelargonium graveolens (geranium), Rosmarinus officinalis (rosemary) and Ocimum basilicum (sweet basil) were investigated for their cidal activities against the egg and adult stages of C. cephalonica. On ovicidal action, among the EOs tested P. betle was found to have higher cidal action to eggs (EC50 3.79 mg/ dm3), followed by T. ammi EO (EC50 4.17 mg/ dm3). P. graveolens and P. betle EOs caused the highest fumigant toxicity in adults with the lowest LC50 values (12.58 and 18.01 mg/ dm3). All the EOs tested caused an antennal response in C.cephalonica female adults. Among the Eos, R. officinalis and P. graveolens elicited the highest antennal response in female moths (1.3 mV and 0.84 mV). In the behavioural assay, the female moths showed reduced preference for the oviposition substrate treated with EOs. The desirable cidal, physiological and behavioural response of EOs on C. cephalonica adults makes them a viable alternative to synthetic pesticides.

Transinfected Wolbachia strains induce a complex of cytoplasmic incompatibility phenotypes: Roles of CI factor genes.

Wolbachia can modulate the reproductive development of their hosts in multiple modes, and cytoplasmic incompatibility (CI) is the most well-studied phenotype. The whitefly Bemisia tabaci is highly receptive to different Wolbachia strains: wCcep strain from the rice moth Corcyra cephalonica and wMel strain from the fruit fly Drosophila melanogaster could successfully establish and induce CI in transinfected whiteflies. Nevertheless, it is unknown what will happen when these two exogenous Wolbachia strains are co-transinfected into a new host. Here, we artificially transinferred wCcep and wMel into the whitefly and established double- and singly-transinfected B. tabaci isofemale lines. Reciprocal crossing experiments showed that wCcep and wMel induced a complex of CI phenotypes in the recipient host, including unidirectional and bidirectional CI. We next sequenced the whole genome of wCcep and performed a comparative analysis of the CI factor genes between wCcep and wMel, indicating that their cif genes were phylogenetically and structurally divergent, which can explain the crossing results. The amino acid sequence identity and structural features of Cif proteins may be useful parameters for predicting their function. Structural comparisons between CifA and CifB provide valuable clues for explaining the induction or rescue of CI observed in crossing experiments between transinfected hosts.

Cinnamon Oil Encapsulated with Silica Nanoparticles: Chemical Characterization and Evaluation of Insecticidal Activity Against the Rice Moth, Corcyra cephalonica

Cinnamon (Cinnamomum zeylanicum Blume) essential oil has vast potential as an antimicrobial but is limited by its volatility and rapid degradation. To decrease its volatility and prolong the efficacy of the biocide, cinnamon essential oil was encapsulated into mesoporous silica nanoparticles (MSNs). The characterization of MSNs and cinnamon oil encapsulated with silica nanoparticles (CESNs) was estimated. Additionally, their insecticidal activity against the rice moth Corcyra cephalonica (Stainton) larvae was evaluated. The MSN surface area decreased from 893.6 to 720 m2 g−1 and the pore volume also decreased from 0.824 to 0.7275 cc/g after loading with cinnamon oil. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and N2 sorption by Brunauer–Emmett–Teller (BET) confirmed the successful formation and evolution of the synthesized MSNs and CESN structures. The surface characteristics of MSNs and CESNs were analyzed by scanning and transmission electron microscopy. Compared with the sub-lethal activity values, the order of toxicity after 6 days of exposure was MSNs ˃ CESN ˃ cinnamon oil ˃ silica gel ˃ peppermint oil. The efficacy of CESNs gradually increases its toxicity more than MSN after the 9th day of exposure.

Gonadotrophic effects of RH-5849, a non-steroidal ecdysone agonist on the rice moth Corcyra cephalonica St. (Lepidoptera: Galleriinae)

In several areas throughout the world, the eggs of the fictitious host insect, Corcyra cephalonica, are used to produce multiple natural enemies, such as Trichogramma species, which are widely utilized for biological control of lepidopterous pests on diverse crops in more than 30 nations. The purpose of this study was to determine the efficacy of RH-5849, a non-steroidal ecdysone mimic, on the gonadotrophic parameters of the rice moth, Corcyra cephalonica. The separated II instar larva received the compound topically on the abdomen dorsum by means of Hamilton micro syringe in acetone. Five replicates (50 insect/replicate) were used per each dosage. Similar replicates were used for the control insects without any treatment. The mean number of eggs laid by a female moth was worked out on the basis of the total number of eggs laid by ten females. In a dose-dependent way, the sterility percentage was enhanced while the hatching percentage was decreased. The sterility indices were shown to be dose-dependent, according to current data. It should not be forgotten that the hatching percentages reversed this effectuation tendency (egg viability).

Life tables and a physiologically based model application to Corcyra cephalonica (Stainton) populations

The rice moth Corcyra cephalonica is a harmful insect pest for grains stocked in storage systems. Its infestations represent a serious concern among producers, because of the non-marketability of the products affected by it and subsequent economic losses.New technologies are improving the supply chain of the stored grains, in line with the integrated pest management framework. However, a prompt control action also requires an in-depth knowledge of insect pests’ biology and their response to environmental parameters. If this information is available, it can also be translated into mathematical language. The modelling of insect pest populations is increasing in utility, particularly if the models are included in decision support systems.The aim of this work concerns two aspects of a model application and validation. Since physiologically based models require information about interactions between species and environment, C. cephalonica individuals were reared at different constant temperatures: 18, 21, 24,26, 28, 30,34 and 36 °C. This first part provided the life tables, whose data were used to estimate the parameters of the Logan, Briére, and Sharpe and De Michele development rate functions.The second part of the work concerns the application of a physiologically based model described by a first order partial differential equation. The validation of the simulations was conducted with a semi-field experimentation with three repetitions.Results showed that the life tables are well represented by the Sharpe and De Michele development rate function, and that the physiologically based model proposed is reliable in representing field populations.

The Intruding Wolbachia Strain from the Moth Fails to Establish Itself in the Fruit Fly Due to Immune and Exclusion Reactions.

Wolbachia is capable of regulating host reproduction, and thus of great significance in preventing the spread of insect-borne diseases and controlling pest insects. The fruit fly Drosophila melanogaster is an excellent model insect for understanding Wolbachia-host interactions. Here we artificially transferred the wCcep strain from the rice moth Corcyra cephalonica into D. melanogaster by microinjection. Crossing experiments indicated that wCcep could induce a high level of CI in the phylogenetically distant host D. melanogaster and imposed no negative fitness costs on host development and fecundity. Based on quantitative analysis, the titres of wCcep and the native wMel strain were negatively correlated, and wCcep could only be transmitted in the novel host for several generations (G0 to G4) after transinfection. Transcriptome sequencing indicated that the invading wCcep strain induced a significant immune- and stress-related response from the host. An association analysis between the expression of immune genes attacin-D/edin and the titre of Wolbachia by linear regression displayed a negative correlation between them. Our study suggest that the intrusion of wCcep elicited a robust immune response from the host and incurred a competitive exclusion from the native Wolbachia strain, which resulted in the failure of its establishment in D. melanogaster.

Development of rice moth Corcyra cephalonica on sorghum based growth media

Laboratory experiment was conducted to evaluate the life cycle of rice moth Corcyra cephalonica (Stainton) on sorghum grains based growth media. Life parameters viz., larval, pupal and total developmental period, adult emergence and sex ratio were evaluated. The larval period was the shortest in first and third instars and longest in sixth instar. The adult emergence observed was 56.66% with 49.99% female moths.

Electroantennographic response of rice moth Corcyra cephalonica stainton to some plant volatiles

Electro antennogram (EAG) responses from male and female antennae of rice moth Corcyra cephalonica (Lepidoptera: Pyralidae) were observed for 18 plant volatiles at four concentrations (0.1, 1.0, 10 and 100 mg/ml). Mean EAG amplitude relative to hexanal, which was used as standard, revealed the significant differences in response to these from both male and female antennae. Among all the compounds (R)-(+)-Limonene, hexanal, cis-jasmone and acetophenone were found to be eliciting significant response from both male and female antennae.

Effects of cold storage on the chemical composition of Corcyra cephalonica eggs by 1H NMR spectroscopy

Rice moth Corcyra cephalonica eggs, frequently utilized as factitious hosts of Trichogramma wasps, are usually cold-stored for a period of time in order to meet the need of Trichogramma mass rearing. However, compounds in cold stored C. cephalonica eggs can influence the quality and quantity of Trichogramma. In the present study, we used Hydrogen-1 Nuclear Magnetic Resonance (1H NMR) spectroscopy and multivariate statistical analysis to investigate the effect of cold storage on the chemical composition of fresh rice moth eggs (U) and killed embryo eggs cold stored at 4°C for 0 (CK), 15 (N15), 30 (N30), 45 (N45), and 60 (N60) days, respectively. A total of 56 compounds were identified and quantified for each treatment, including amino acids, nucleic acid components, organic acids, sugars, and amides. Principle component analysis (PCA) and partial least square discriminant analysis (PLSDA) demonstrated that cold storage had a pronounced effect on the chemical composition of rice moth eggs. Three groups, U and CK, N15 and N30, and N45 and N60, were classified by their components’ similarity. The primary components that contributed to difference among three groups were alanine, glutamine, glucose and acetate, the concentrations of which significantly changed with the increasing of cold storage days. Thus, cold storage elicits changes in the chemical compositions of rice moth Corcyra cephalonica eggs, which may affect the growth and development of Trichogramma.

Vapormate® as a fumigant for the control of mealybugs in pineapple and pests of stored rice and maize

Experiments were carried out at the National Plant Quarantine Service at Katunayake and at the Food Research Unit at Gannoruwa, Peradeniya, Sri Lanka to evaluate the efficacy of Vapormate® (Ethyl formate 16.3% w/w in liquid carbon dioxide 83.7% w/w), against mealybugs in pineapples [Ananas comosus (L.) Merr.] and stored grain pests of rice (Oryza sativa L.) and maize (Zea mays L.). Vapormate® is an eco-friendly safer alternative for Methyl Bromide, and accepted worldwide for quarantine and non-quarantine treatment of food items, packaged and stored foods and processing equipment. Fumigation standards recommended by the manufacturer for pineapples (4h exposure of 360g Vapormate®/m3) resulted 100% mortality in mealybugs, (Dysmicoccus brevipes), without deteriorating the organoleptic and physicochemical properties of the fruits. The recommended fumigation stand-ards by the manufacturer for stored grains (24h exposure of 420 g Vapormate®/m3) found to be highly effective in controlling both larvae and adults of stored grain pests of rice and maize namely, maize weevil (Sitophilus zeamais), rice weevil (Sitophilus oryzae), red flour beetle (Tribolium castaneum), confused flour beetle (Tribolium confusum) and rice moth (Corcyra cephalonica). Therefore, Vapormate® can be recommended for pre-shipment fumigation of pineapples and for pre-entry and non-quarantine treatment of stored rice and maize in Sri Lanka as recommended by the manufacturer.

Comparative susceptibility of Corcyra cephalonica (Lepidoptera: Pyralidae) eggs to carbon dioxide and nitrogen at different temperatures

The aim of this study was to evaluate the susceptibility of the egg stage of the rice moth Corcyra cephalonica to modified atmospheres (MAs) enriched with CO2 or N2 at 25, 30 and 35 °C combined with various exposure times. The tested modified atmospheres containing CO2 were 20% CO2, 16% O2 and 64% N2; 40% CO2, 12% O2 and 48% N2; 60% CO2, 8% O2 and 32% N2 and 80% CO2, 4% O2 and 16% N2. The tested modified atmospheres containing N2 were 97% N2 and 3% O2 and 98% N2 and 2% O2. The results showed that the hatchability responding to modified atmospheres enriched with either CO2 or N2 decreased significantly with an increase in exposure time, gas content (%) and temperature. All tested combinations provided complete (100%) egg control in less than 4 days. Based on 100% mortality, shorter exposures were obtained with 80% CO2 than with N2 at most tested temperatures. The modified atmospheres enriched with 98% N2 were more effective than 97% N2 against C. cephalonica eggs, especially at 35 °C. It is recommended to use high levels of CO2 in air (80%) and N2 (98%) in controlling 0–24-h-eggs of C. cephalonica within 24–36 h for CO2 and 18–72 h for N2.

Storage insect pests and their damage symptoms: an overview

Stored product pests gain access to the grain storage from the standing crop in the field to various stages of grain processing and storage. Although, about one thousand species of insects have been associated with stored products in different parts of the world, a few pests are considered as pests causing severe damage to the stored grains. The stored grain insect pests can be categorized on the basis of their feeding behaviour as internal and external feeder or as major and minor pests based on the severity of damage, they cause. This paper gives an overview of damage symptoms and biology of some of the major pests of stored grains viz., rice weevil, Sitophilus oryzae, lesser grain borer, Rhyzopertha dominaca, khapra beetle, Trogoderma granarium, red flour beetle, Tribolium castaneum, cigarette beetle, Lasioderma serricorne, drug store beetle, Stegobium paniceum, pulse beetles Callosobruchus spp., Angoumois grain moth, Sitotroga cereallela, rice moth Corcyra cephalonica, saw toothed grain beetle Oryzaephilus surinamensis, long headed flour beetle, Latheticus oryzae, and almond moth Cadra cautella.

Development and reproductive performance of rice moth Corcyra cephalonica Stainton (Lepidoptera: Pyralidae) in different rearing media

The study aimed to evaluate different rearing media for mass production of rice moth Corcyra cephalonica Stainton (Lepidoptera: Pyralidae) an important host of several bio-control agents. The development and reproductive performance of Corcyra was evaluated to twelve (12) different combinations of food containing maize, wheat, Italian millet and scented rice-alone and fortified with 3% dextrose and yeast. Results showed that the net reproductive rate; innate capacity for increase; number of hypothetical females; daily finite rate of increase; weekly multiplication; and potential fecundity were highest and true generation time and doubling time were shortest in Italian millet (alone/fortified). The performance was better in wheat alone (second to Italian millet) than its fortification with dextrose and yeast and also superior to maize and scented rice. Hence, Italian millet alone or fortified with 3% dextrose and yeast was the most suitable rearing media for mass production of Corcyra.

Grain storage and insect pests of stored grain in rural Niger

We surveyed 1293 farmers and traders in southern Niger to learn about their grain storage practices and their views on the storage pest problem. We identified the insect species found in samples obtained from 40 localities in three regions of the country. We stored 371 grain samples collected from respondents in the laboratory for seven months to allow populations of the insects present to develop and emerge and the resultant grain weight loss to be determined. The commodities most commonly stored in Niger were millet and sorghum, kept in storage on average for about 6 months by 53% and 80% of respondents respectively. When millet samples from respondents were kept in the laboratory for seven months, two pests were found, the rice moth Corcyra cephalonica Stainton, and Tribolium spp. This millet experienced a weight loss of 17.1% during seven months storage. Tribolium castaneum Herbst, Sitophilus granarius L., Cryptolestes spp, Sitotroga cerealella Oliver, Trogoderma granarium Everts, Rhyzopertha dominica F. and C. cephalonica were found in stored sorghum, which lost 10.1% weight after seven months. Eleven other grains or foods were stored by 2.9–24.4% of respondents. Recorded weight losses were 15.9% for groundnuts, 12.6% for paddy rice, 7.6% for sesame and 7.4% for maize. Seeds of Hibiscus sabdariffa L. and Bambara groundnut were essentially destroyed by bruchids during storage, mean weight losses being 83.9% and of 61.8% respectively. Most respondents took no measures to control insect pests in their stored grains. Food security and quality in Niger would be greatly improved if Africa-manufactured technology that is safe, low-cost, insecticide free, and widely available could be implemented for postharvest storage of food grains.

A novel Wolbachia strain from the rice moth Corcyra cephalonica induces reproductive incompatibility in the whitefly Bemisia tabaci: sequence typing combined with phenotypic evidence.

Wolbachia are a group of maternally inherited bacteria frequently found in arthropods and filarial nematodes. They have recently attracted attention for their ecological roles in manipulating host reproduction, their potential use in biological control of pest insects and medical significance. Classification of Wolbachia strains is currently solely based on molecular methods. However, the strains even with identical sequence types may induce different host phenotypes. Here we isolated a Wolbachia strain from the rice moth Corcyra cephalonica (designated as wCcep_B_BJ), which was shown to share multilocus sequence typing and Wolbachia surface protein hypervariable region profiles with a cytoplasmic incompatibility (CI)-inducing strain in supergroup B, but the phenotype wCcep_B_BJ may induce needs to be determined. We thus transinfected it into the whitefly Bemisia tabaci harbouring an A-Wolbachia through nymphal microinjection. Fluorescent in situ hybridization demonstrated that wCcep_B_BJ was successfully transinfected into B. tabaci and transmitted to offspring through host eggs. Reciprocal cross showed that wCcep_B_BJ induced a strong bidirectional CI in the transinfected host without imposing a significant cost on female fecundity. Our results suggest that wCcep_B_BJ may be a promising strain for biocontrol of B. tabaci, an important agricultural pest insect.

EFFECT OF CALLISTEMON LANCEOLATUS (MYRTACEAE) LEAF OIL VOLATILES ON EGG HATCHABILITY OF CORCYRA CEPHALONICA AND ITS GAS CHROMATOGRAPHY-MASS SPECTROMETRY ANALYSIS

Callistemon lanceolatus (Myrtaceae) plant claimed for the management and control of rice - moth Corcyra cephalonica an insect pest of stored commodities. When freshly laid eggs were exposed to Callistemon lan ceolatus oil volatiles for 12, 24, 48, and 72 h with 20, 40, 80 or 160 µ l of oils, a marked decline in egg hatchability in this pest was seen after exposure period. The oil having insecticidal properties w h ich was extracted by Clevenger apparatus in the laboratory by hydro - distillation process, subjected to Gas chromatography - mass spectrometry technique. The presence of active ingredients of Callistemon lanceolatus oils obtained at 0.001 % yield by hydro - distillation mainly consisted of 1, 8 Cineole*62.25 %; Alpha - terpineol*8.73; D - limonene*8.40 %; Alpha Pinene*7.03 %; Alpha Phellendrene*2.85 %; Linalool*0.67 % etc. The result offers a platform for using Callistemon lanceolatus leaf oils for control and management of rice moth Corcyra cephalonica in godo wns, warehouses around the world.

Potential of an Insect Growth Regulator in the Management of the Rice Moth Corcyra Cephalonica Stainton, 1866 (Lepidoptera: Pyralidae)

Abstract The present investigation reveals the influence of methoprene, an IGR, on the ontogeny, growth duration and adult longevity of the rice moth Corcyra cephalonica. Twenty-five larvae of different instars (1st, 2nd, 3rd and 4th) of C. cephalonica were exposed to the juvenile hormone analogue methoprene in order to evaluate its potential effect on larval mortality, pupation, pupal mortality, adult emergence, growth duration and adult longevity. These different instars larvae were treated with 2, 4, 8 and 12 ppm of methoprene in an artificial diet (coarsely ground jowar mixed with 5% yeast powder) where the control received acetone alone. The results reveal significant differences in all the parameters mentioned above as compared to the control.