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The rice moth, Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) is a harmful insect pest for grains in storage systems. However, there is a lack of available data on the effect of ozone on rice moth. In this study, we assessed the ozone at concentrations of 1.0, 3.0, and 5.0 g/m3 for six-time intervals (0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 h) on the mortality of insect life stages as well as pupation and adult emergence. The results showed that for all stages, the percent of mortality increased with increasing concentration and exposure time with 5.0 g/m3 and 5.0 h of exposure time resulted in 100.0% egg mortality. The highest mortality of treated larvae (89.1%) and pupae (96.2%) resulted after 5.0 h exposure to 5.0 g/m3 of ozone. Also, the results showed that the treated adults were more sensitive to ozone than the three other stages. A complete adult mortality was achieved by all concentrations of ozone at the following exposure times, 5.0 h after 1.0 day of treatment, 4.0 h after 2.0 days of treatment and 2.0 h after 3.0 days of treatment. Beside the effect on mortality, ozone suppressed the pupation and adult emergence from treated immature stages. The chemical analysis of treated wheat flour showed a slight decrease in protein, fat, carbohydrate, moisture and fibre and a slight increase in ash contents compared with untreated wheat flour. Our findings suggest that ozone can be effectively used for the control of C. cephalonica in stored wheat flour. [ABSTRACT FROM AUTHOR]

Asian corn borer (ACB), Ostrinia furnacalis Guenee (Lepidoptera: Crambidae) and the rice moth (RM), Corycyra cephalonica Stainton (Lepidoptera: Pyralidae) are economically significant insect pests that threaten the agricultural products worldwide. Trichogramma parasitoids are successfully mass-reared using artificial host eggs, RM, and are often managed by economically important lepidopterous pests, such as ACB in China. Trichogramma ostriniae Pang and Chen (To) and T. dendrolimi Matsumura (Td) (Hymenoptera: Trichogrammatidae) are two important parasitoids of ACB. To determine the influence of interspecific competition between To and Td on their offspring’s emergence. We determine the emergence of wasp progeny from two distinct hosts (ACB and RM eggs) of varying densities (10, 20, 30, and 100) by examining the effect of three distinct oviposition sequences (To-Td, Td-To, and To+Td) by two Trichogramma species. We discovered that the progeny emergence rate of To and Td from the host was substantially influenced by the parasitoid types, host types, oviposition sequences, and host densities, and their two-, three-, and four-factor interactions while investigating the ACB and RM eggs after oviposition. Additionally, the progeny of Td emerged from 10, 20, and 30 ACB host eggs under three oviposition sequences, which was significantly higher than that of ACB eggs of 100 densities. Nevertheless, the optimum emergence rate of Td progeny was also observed in ACB eggs with a density of 100 under all oviposition sequences. The most suitable oviposition sequences for both wasp species are To-Td and Td-To, as they have the highest rate of progeny emergence. The progeny emergence of both Trichogramma species from RM eggs of varying densities was observed to be significantly different. Nevertheless, the most influential density is 100 RM eggs, as a result of the maximal emergence rate of To and Td. Overall, it is concluded that host eggs with a density of 100 are adequate to meet the oviposition requirements of both wasps in all oviposition orders, thereby limiting their interspecific competition. These findings provide insights into optimizing host density and oviposition strategies for mass-rearing Trichogramma species, which can enhance their efficacy in biological control programs. Future research should explore field-level applications to validate these laboratory findings under natural conditions.

The experiment was conducted at the Acarology Laboratory, Department of Entomology and Agricultural Zoology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India. The results of morphometric measurements revealed that the mean egg length and breadth were 0.58 and 0.33 mm, respectively. The mean length of different instars namely first, second, third, fourth, fifth and sixth was found to be 1.15, 1.36, 2.79, 4.98, 5.79 and 8.43 mm, respectively and the average breadth was 0.16, 0.23, 0.33, 0.67, 0.84 and 1.46 mm, respectively. The mean length of the pupa was 8.04 mm, and the breadth was 1.23 mm. The mean measurement across the expanded wings of male moths was 17.44 mm and in females it was 19.17 mm, whereas the mean body length of males was 9.43 mm and in females, it was 10.22 mm. [ABSTRACT FROM AUTHOR]

In order to investigate the larval development and damage characteristics of the rice moth Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) on rice, larvae of C. cephalonica were reared on brown rice, polished rice, wash-free rice, rice bran, and rice powder at 25ºC, 55% relative humidity (RH), and a 16:8 light-dark cycle. The shortest larval developmental period was found on brown rice (51.2 days) while the longest was found on rice powder (171.5 days). There were no significant differences in developmental periods among polished rice, wash-free rice, and rice bran. The emergence rate was exceptionally low on rice powder (53.3%) compared to other diets (over 80%). The examination of each kernel of brown rice after emergence showed that this species selectively damages rice germ, with a secondary preference for rice bran. These results suggest that dietary rice germ and rice bran are relatively suitable for the larval development of the rice moth. [ABSTRACT FROM AUTHOR]

Extent of parasitization by Trichogramma chilonis was tested for two consecutive years (2020-2021) at AICRP on Biological control, Regional Agricultural Research Station, Anakapalle, Andhra Pradesh, India by taking factitious host Corcyra cephalonica and Samia cynthia ricini to assess the predilection ethology towards host eggs whilst Trichogrammatids that developed after emerging from C. cephalonica preferred its eggs (85.00%) over erisilkworm eggs (72.33%) for parasitization under circumstances subjected to no choice Similarly, trichogrammatids that erupted from eggs of eri silkworm in the absence of free choice as well opted C. cephalonica eggs (80.00%), when compared to erisilkworm eggs (75.33%) for parasitization. Trichogramma chilonis parasitoids that emerged out from the eggs of rice moth documented higher percent egg parasitisation on rice moth eggs (91%) especially in contrast to eri silkworm eggs (71.33%) in free choice test, whilst the study of emergence pattern of T. chilonis from eri silkworm eggs has unveiled higher proclivity for parasitization of rice moth eggs (83.66%) contrary to eri silkworm eggs (73.66%). Although, the percent parasitization was comparatively higher in rice moth than eri silkworm egg on the other hand eri silkworm can still be used as a substitute as well an alternate host to rice moth in Trichogramma production as the size of eri silkworm egg (0.87±0.99 mm) is three times larger as well as it can accommodate more number of Trichogrammatids (9-10) than rice moth egg (0.34±0.38 mm) which accommodate only one trichogrammatid. [ABSTRACT FROM AUTHOR]

Eocanthecona furcellata (Wolff) is a potential native predator of lepidopteran larvae that can be easily reared under laboratory conditions and released in augmentative biocontrol for management of pests in various crops. For successful mass production of any predator cannibalism under crowded rearing conditions is the major limiting factor. In the present study, attempts were made to know the ideal population considered for group rearing with minimal or no cannibalism. It was recorded that the predator population of 5 to 25 on Corcyra cephalonica (S.) and Galleria mellonella L. and 5 to 30 on Samia cynthia ricini Boisd. and Spodoptera litura F. was feasible for group rearing with higher percent survival rate when reared in different group arenas. The survival percent was higher on hosts, C. cephalonica, G. mellonella, S. litura and recorded lower on S. cynthia ricini under group rearing condition. [ABSTRACT FROM AUTHOR]

Under laboratory conditions, the virulence of the Kashmir isolate of EPN, Heterorhabditis bacteriophora (SKUASTK-EPN- Hr 01) to Galeria mellonella, Corcyra cephalonica and Bombyx mori showed that after 48-72 h, 100% mortality was recorded in all the test insects. Considering 48 h time and 20 IJs/larva as standard against G. mellonella, C. cephalonica and B. mori, the LC50 and LT50 values for the EPN were 10.17, 28.72 and 23.81 IJs/larva, and 38.64, 53.04 and 49.20 h after exposure, respectively. Again its virulence to the larvae of three different sizes of these insects, viz., small (0.12g, 0.04g, 0.17g), medium (0.18g, 0.05g, 0.59g) and large (0.22g, 0.07g, 2.58g) sized larvae showed that all the three sizes of G. mellonella were more susceptible than that of B. mori and C. cephalonica. Considering 20 IJs/ larva as standard against small, medium and large sized larvae, the LT50 value for the EPN was 25.00, 26.45 and 27.21 h; 47.73, 48.92 and 53.16 h, and 46.04, 47.48 and 48.92 h for G. mellonella, C. cephalonica and B. mori, respectively. The production of nematode infective juveniles per larvae was directly proportional to the size and/or body weight of the insect species tested. The average production of nematode infective juveniles per gram of host body weight ranged from 1557.79 to 1933.55 x 10³, 217.38 to 335.43 x 10³ and 71.03 to 128.00 x 10³ in G. mellonella, C. cephalonica and B. mori, respectively. The total time period between the larval mortality and the initiation of emergence, and between larval mortality and the cessation of emergence of nematode infective juveniles from the cadavers ranged from 7-10, 6-8 and 9-12 days, and 19-28, 16-24 and 23-41 days in G. mellonella, C. cephalonica and B. mori, respectively. [ABSTRACT FROM AUTHOR]

Biological control efficiency can be improved by developing effective mass‐rearing systems to produce large numbers of high‐quality parasitoids. This study explored an alternative host for rearing Sclerodermus brevicornis (Kieffer) (Hymenoptera: Bethylidae), a potential biocontrol agent for the suppression of exotic and invasive wood‐boring longhorn beetle (Coleoptera: Cerambycidae) populations in the European agroforestry ecosystems. We tested larvae of the rice moth, Corcyra cephalonica Stainton (Lepidoptera: Pyralidae), as host for the parasitoid. We quantified the probability and timing of host attack and parasitism as well as reproductive success, offspring production, and the characteristics of adult offspring. As S. brevicornis is a quasi‐social species (multiple females, communally produced offspring broods), we also explored the effects of varying the number of females to which individual hosts were presented, with the aim of determining the optimal female‐to‐host ratio. As time to host attack can be a limiting factor in S. brevicornis rearing protocols, we tested the use of adult females of another bethylid species, Goniozus legneri Gordh, to paralyse C. cephalonica larvae prior to presentation. We identified the conditions within our experiment that maximized offspring production per host and offspring production per adult female parasitoid. We found that C. cephalonica is suitable as a factitious host and, as it is considerably more straightforward for laboratory rearing than cerambycid species, it is a good candidate for adoption by future S. brevicornis mass‐rearing and release programmes. [ABSTRACT FROM AUTHOR]

The laboratory experiment was conducted during 2017-2018 to study the different biological attributes of Trichogramma chilonis Ishii as influenced by host eggs of different ages. Significantly maximum percent egg parasitization was noticed on eggs of Helicoverpa armigera (Hübner) with 62.39 percent which was at par with the Corcyra cephalonica (Stainton) eggs (60.36 percent). This was followed by Earias vittella Fabricius 46.31 percent. Less parasitized eggs were recorded in Leucinodes orbonalis Guenée (10.35 percent). Age of host eggs significantly affected the parasitization by T. chilonis. The maximum parasitization (58.87 percent) was noticed in fresh eggs i.e. 24 hrs old followed by 48 hrs (44.91 percent) while 72 hrs old eggs were less preferred by T. chilonis and could parasitize only 30.56 percent. Development period for parasitoid ranged between 8.66 to 9.44 days on different host eggs. The highest adult parasitoid longevity (7.22 days) was observed from the parasitized eggs of H. armigera which was at par with C. cephalonica (7.10 days), E. vittella (6.88 days) and L. orbonalis (6.88 days). However, the different lepidopteran eggs as well as age of host eggs did not show significant differences pertaining to percent adult parasitoid emergence. Fresh host eggs of 24 hrs could produce more female progeny of T. chilonis (54.30 percent) compared to 72 hrs old eggs (42.65 percent). The sex ratio (male: female) of emerging parasitoid progeny was observed highest on 24 hrs old eggs (1:1.55) followed by 48 hrs old eggs (1:1.23) while lowest sex ratio was observed on the eggs of 72 hrs old age (1:0.95). The maximum per day fecundity of T. chilonis was noticed on the 24 hrs old eggs (6.75) followed by 48 hrs old eggs (4.80). The lowest fecundity (2.05) of T. chilonis was observed on the 72 hrs old eggs, whereas the highest male-female ratio and fecundity was noticed on eggs of E.vittella among different hosts. [ABSTRACT FROM AUTHOR]

Eight isolates of entomopathogenic fungi were evaluated as dried conidia against the rice moth, Corcyra cephalonica. In bioassays two isolates of Beauveria bassiana (BbGc and BbPs) and one isolate of Metarhizium anisopliae (MaPs) consistently gave high mortality to C. cephalonica larvae. Formulations in either kaolin, talc or tapioca flour (20 % w/w a.i.) thoroughly mixed with long grain rice in plastic cups (8 cm diameter by 5 cm) gave complete larval mortality by the 12th day of treatment. However, in general those formulated in kaolin and talc were more efficacious and faster to kill compared to those formulated in tapioca flour or the unformulated control. Even at the lowest rate of 0.05 g BbGc in kaolin provided 100% mortality 7 days after introduction compared with other dust formulations. Isolate BbGc in kaolin and talc administered at 0.4 g a.i. in 200 g rice packed in plastic kept at room temperature provided protection against the rice moth up to 4 months of storage. Larval mortality in excess of 90% was obtained 15 days after introduction. Formulations of MaPs was effective only within the first month of storage beyond which infectivity rapidly declined.

In India, the egg parasitoid Trichogramma chilonis Ishii is generally mass produced on the eggs of rice moth, Corcyra cephalonica Stainton, however, in the present study, the cost of production of T. chilonis was studied on Samia cynthia ricini, eri silkworm, and was compared with rice moth. Rearing of T. chilonis on eri silkworm eggs showed higher benefit cost-ratio of 1.89 with a net profit of Rs. 4620, whereas T. chilonis when reared on the eggs of C. cephalonica recorded a benefit cost ratio of 1.28, with a net profit of Rs. 2379. The results revealed that in one hectare area, one trichocard made from eri silkworm eggs release that containing 3500 eggs. Each parasitized egg yields 9-10 adults, thus total adults account to about 35000-40000 adults ha-1, while in case of trichocard made from rice moth eggs, the number of cards to be released in one hectare area are 2-3, since one trichocard made from rice moth eggs consit of 16000-17000 eggs. Hence, eri silkworm can be used as an alternate host to rice moth for rearing of T. chilonis as it is a resource efficient and cost reducing technology. Further, this production technology would be suitable for promoting localized production of eri silkworm at village level especially for tribal farmers, and unemployed youth. [ABSTRACT FROM AUTHOR]

Habrobracon hebetor has been investigated as a successful biological control agent for larvae of pyralid moths in warehouses. Gaining new information on how to improve the storage procedure of H. hebetor under cold conditions could allow the development of approaches to maintain this parasitoid in pest management programs. This study investigated the effect of cold temperatures (10 and 15 °C) on the development of H. hebetor pupae reared on Corcyra cephalonica, which was kept for up to 3 weeks. Mortality of H. hebetor pupae during cold storage in all treatments was 4 - 19%. Mortality of H. hebetor adults emerging during cold storage at 10 °C (28%) and 15 °C (61%) was significantly observed at 21 days of storage, while other treatments were less than 4%. Numbers of emerging adults after cold storage from 7 - 14 days were 89 - 96%, and the female percentage ranged from 13 - 39%. The number of eggs laid per female from the emerging females after cold storage for 7 - 14 days was not significant as compared to the control treatment (43 - 53 eggs per female) after laying for 72 h. The sex ratios of emerging adults in all cold storages and the control treatment at 72 h after emerging were not significant. [ABSTRACT FROM AUTHOR]

The mass production of widely used bio-control agent Trichogramma chilonis primarily depends on the constant supply of their host eggs and availability of suitable storage techniques. Experiments were conducted to develop such techniques of three Trichogramma chilonis Ishii strains (viz. Nilgiris, Kodaikanl and lab) on stored and un-stored Corcyra cephalonica eggs. Differential response was noticed when pupal storage was attempted on un-stored host eggs at 5 and 10 °C. At 10 °C (L: D- 8:16, RH-70 ± 10%), T. chilonis Nilgiris strain could retain its developmental arrest for the longest duration (60 days), followed by T. chilonis Kodaikanal (50 days). All the three tested strains showed a reduced storage capacity at 5 °C (L: D- 0:24, RH-70 ± 10%). However, T. chilonis Nilgiris and Kodaikanal strains could be stored for upto 35 days with 60% emergence rate and lab strain for upto 30 days where emerged adults could survive for 3 days. The study revealed that when stored host eggs are used, the parasitized cards (parasitoids in their pupal stage) are amenable for further storage of minimum 30 days at both 5 and 10 °C. To overcome seasonal fluctuation in host availability, stored C. cephalonica eggs can be used to store pupal stages of the three different strains of T. chilonis at 5 °C for a total duration of 50 days (host egg storage: 20 days + pupal T. chilonis storage: 30 days). [ABSTRACT FROM AUTHOR]

Chelonus blackburni (Cameron) that parasitizes eggs of potato tuber moth is widely distributed and occurs commonly in potato fields throughout the country. Studies on its biology and ovipositional performance were carried out on both hosts i.e. Phthorimaea operculella and Corcyra cephalonica in laboratory conditions. Average number of eggs laid per female was found to be 210.9 ± 16.62 on P. operculella and 118.4 ± 7.49 on C. cephalonica. Incubation period of the parasitoid on P. operculella was 24.5 ± 1.62 hours on an average, while on C. cephalonica, it was found as 25.2 ± 1.33 hours. Total larval duration was 14.5 days and 19.2 days on P. operculella and C. cephalonica, respectively. Pupal period was 10.6 ± 0.70 days on P. operculella, whereas it was slightly higher on C. cephalonica (13 ± 0.57 days). The average life span was observed to be 6.8 days on P. operculella and 7.7 days on C. cephalonica. [ABSTRACT FROM AUTHOR]

The competition between Idaea inquinata, Corcyra cephalonica, and Plodia interpunctella on an artificial diet was investigated. The experiments were carried out with eggs laid within 24 hours. In the first experiment, 20 eggs of one species were placed in a ventilated Petri dish with 10 g of diet and 20 eggs of one of the other species; in the second experiment, 20 eggs of one species and, after 7 days, 20 eggs of one of the other species were added. Experiments were carried out at 27±1 °C, 70±5% R.H. Each experiment was replicated 5 times and the number of days to complete the development and the number of emerged adults were recorded. The number of P. interpunctella adults was not affected by the presence of C. cephalonica or I. inquinata. A delay in the development was only observed when P. interpunctella eggs were added to the medium already colonized by the other species. I. inquinata was the less competitive, as the number of adults decreased and the days to complete the cycle increased. The development of I. inquinata was prevented if P. interpunctella eggs were started at the same time. Larvae of this last species cannibalized eggs of the other two species. I. inquinata was the least competitive due to the longer cycle, the lower mobility and the aggressiveness of the larvae of the other two species that cannibalized its eggs. [ABSTRACT FROM AUTHOR]

Effect of modified atmospheres (MAs) containing CO2 at 20, 40, 60 and 80% or containing N2 at 97 and 98% on the mortality of Corcyra cephalonica Stainton (Lepidoptera: Pyralidae) sixth instar larvae was studied to determine the LT values at 30 °C. The respiration rates of untreated and treated larvae with 60% CO2 and/or 98% N2 at LT50 were measured using Q-Box RP1LP low range respirometry package. Total protein and triglycerides of treated and untreated larvae were assayed. Complete larval mortality was recorded after 72 and 144 h of treatment with 60% CO2 and 98% N2, respectively. Calculated LT50 values were 39.3 at 60% CO2 and 87.5 h at 98% N2 MAs. Respiration quotient (RQ) in the light of consumed O2 and produced CO2 of untreated larvae was 1.0 while it was 0.85 at 60% CO2 and 0.72 at 98% N2. Duration time necessary for produced CO2 curve to reach the maximum point (2000 ppm) was significantly shorter at untreated larvae (27.64 min) in comparison with that recorded at CO2 (35.48 min) which also significantly less than that obtained at N2 (98.54 min). At all treatments, total protein was decreased while triglycerides were increased in comparison with control. [ABSTRACT FROM AUTHOR]

Recently, a test was conducted in Italy for the evaluation of the biocidal efficacy of Nitrogen saturation (anoxic conditions). One application was carried out in a controlled atmosphere cell of a logistic center specialized in receiving, storing and shipping foodstuffs. The cell, circa 3682 m3 volume, with capacity of 752 big bags of fresh shelled hazelnuts on 4 height levels was saturated with Nitrogen (99,9%) and maintained at 15-18°C for 21 days. Five test species of insects Plodia interpunctella, Cadra cautella, Corcyra cephalonica, Tribolium confusum, Oryzaephilus surinamensis were observed at different development stages (egg, larva, adult). The target species were sorted in special biotest and inserted in the big bags to simulate an infestation. At the end of the exposure period the biotests were collected and analyzed. The treatment resulted sufficient to achieve a total control on eggs of Lepidoptera test species only. This result confirmed and integrates the available information in literature that showed the need of a longer minimum exposure period for total control of common stored pest insects. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The use of thelytokous Wolbachia‐infected Trichogramma (parasitic wasps) has long been considered as a way to enhance the efficacy of biocontrol. However, Wolbachia can affect the host physiology. We compared decision‐making between bisexual and thelytokous Wolbachia‐infected lines of Trichogramma dendrolimi Matsumura regarding behavior toward fresh and old eggs of Corcyra cephalonica at 25 ± 1 °C and 70 ± 5% relative humidity. RESULTS: The behavioral patterns and sequences of the two lines were basically the same. The durations of various behavioral patterns and values of fitness indicators of the bisexual line on fresh eggs were generally significantly shorter and better, respectively, than on old eggs, whereas the thelytokous line behaved similarly toward the two types of eggs, and differences in most fitness indicators between fresh and old eggs were not significant. On fresh eggs, the durations of various behaviors in the bisexual line were generally significantly shorter than in the thelytokous line and the fitness indicators were generally significantly better. CONCLUSION: Wolbachia affected the fitness of T. dendrolimi negatively. The potential of the thelytokous line as a biocontrol agent would not be as good as that of the bisexual line when decision‐making only is considered. Therefore, further evaluations need to be carried out before the thelytokous line can be used in practical biocontrol. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Intraguild predation (IGP) is common in food web when two natural enemies share the same resources and prey. It may affect the success or failure of a biological control attempt. The role of intraguild predation by Geocoris ochropterus Fieber (Heteroptera: Geocoridae) on Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) developed on eggs of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) and Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) was evaluated under laboratory conditions. In choice experiments, both fifth instar nymph and adult of G. ochropterus preferred to predate on unparasitized eggs of H. armigera and C. cephalonica over parasitized eggs. In no-choice experiments, G. ochropterus nymph consumed 58 and 67% of unparasitized H. armigera and C. cephalonica eggs, compared to 3.33 and 7.38% of parasitized ones. A similar trend was observed in no-choice experiments with adult predator. Additional semi-field and field studies are required to explicate the consequences and intensity of intraguild predation in agro-ecosystem. [ABSTRACT FROM AUTHOR]

Egg parasitoid rearing on factitious hosts is an important step to reduce costs and increase availability of the biocontrol agent but it requires quality control to achieve success in field conditions. To this end, this study evaluated the quality of Telenomus remus (Hymenoptera: Platygastridae) reared on Corcyra cephalonica (Lepidoptera: Pyralidae) for until 45 generations. In the first bioassay, we evaluated the body size of the laboratory-produced parasitoids. In the second bioassay, flight activity was examined, measuring the percentage of 'flyers', 'walkers' and 'deformed' parasitoids. The third bioassay assessed parasitism on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs. Our data indicate that the laboratory-reared parasitoid neither lost its ability to fly nor to parasitize S. frugiperda eggs. In conclusion, quality did not decrease significantly during 45 generations, and therefore rearing of T. remus on C. cephalonica as factitious host promises to be successful. [ABSTRACT FROM AUTHOR]

The role of temperature in diapause induction was studied as a mode of long-term storage of Trichogramma chilonis (Ishii) (Hymenoptera: Trichogrammatidae). Three different strains of this widely used biocontrol agent (T. chilonis Nilgiris strain, T. chilonis Kodaikanal strain, and T. chilonis 15 °C strain) reared on the factitious host Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) were used for this experiment. Except T. chilonis laboratory strain, all the other strains could successfully undergo diapause at their pre-pupal stage. Maximum percentage of healthy pre-pupae were recorded in the three strains by providing a pre-storage temperature of 10 °C for 35 days with eight hours of photophase wherein 75-87% could enter into diapause. Further, at a maintenance temperature of 5 °C with 24 hours of scotophase, diapause could be maintained. Diapause could be terminated after six months of storage with 23-36% of adult emergence. However, there was significant reduction in longevity and parasitism rate of the emerged adults. Considering superior biological parameters, 95 days of storage (including pre-storage duration) could provide around 60% adult emergence. Successful long-term storage of T. chilonis strains through diapause induction can facilitate commercial insectaries in stockpiling this biocontrol agent for large-scale field releases. This is the first study on successful induction and termination of diapause in T. chilonis strains and evaluating their performance attributes. [ABSTRACT FROM AUTHOR]

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 ( 1 H 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 . [ABSTRACT FROM AUTHOR]

Nymphs of anthocorid bugs, Blaptostethus pallescens were evaluated @ against 100, 200 and 300 eggs of storage pest Corcyra cephalonica, in 1.0, 2.0 and 3.0 kg. of rice. Important parameters viz. average emergence of host, per cent emergence, per cent reduction in emergence of host and longevity of bugs were observed. Per cent emergence of adult moths of Corcyra cephalonica varied from 5.0 to 96.77, which corresponded to 94.83 and 0.0 per cent reduction over control, respectively, in response to 10, 20 and 30 bugs used. Per cent reduction in host was positively correlated with the number of predatory bugs (r= 0.89** d.f. = 52). Weight of rearing media was found to elicit a non significant correlation with per cent emergence of host (r= 0.26 NS; d.f. = 54). Regression model Y = 48.6 + 1.54 predators -0.0448 host eggs proposed for per cent reduction in host, versus number of predators and number of host eggs was found best fit. [ABSTRACT FROM AUTHOR]

Sycanus collaris Fabricius (Hemiptera: Reduviidae) are voracious and polyphagous reduviid predators of economically important insect pests of agriculture and forest. Only limited work has been done in case of S. collaris, but life history of these predators on Corcyra cephalonica Stainton were documented. The present study was carried out at the Bio-control laboratory, Department of Entomology, College of Agriculture, IGKV, Raipur (C.G.), during February to May, 2018 with an aim to assess influence of various diets fed C. cephalonica larvae on feeding efficiency of reduviid predator, S. collaris, which are responsible for preference and non-preference of reduviid bugs for mass rearing in laboratory conditions. For this experiment, ten freshly hatched first instar S. collaris nymphs were placed in Petri-dish, replicated thrice and larvae of C. cephalonica reared on twelve different diets were provided throughout their life cycle and the feeding efficiency was recorded. Results indicated that feeding efficiency of S. collaris was found to be maximum (183.31) in T1 (Rice), whereas it was found to be minimum (91.33) in T9 (Maize + Groundnut) reared larvae of C. cephalonica. [ABSTRACT FROM AUTHOR]

The role of three different hosts viz., eggs of Corcyra cephalonica, brinjal aphids and mango mealy bugs on development, longevity, larval and pupal period of green lacewing (Chrysoperla carnea), was investigated in laboratory conditions (50 ± 1°C, 70 ± 5 % RH and photoperiod of L16: D8). In this study Chrysoperla was fed on Corcyra eggs, brinjal aphids and mango mealy bugs. Significant effects of host on larval duration, total developmental period, pupal duration, per cent larval survival and adult longevity of green lacewing were observed. The average larval period of C. carnea fed on was 14.40, 15.20 and 15.60, respectively. Pupal duration of 9.45, 10.02 and 9.77, respectively was recorded in same order of prey. Also the adult longevity of adults from eggs Corcyra, brinjal aphid and mango mealy bugs treatment was 25.40, 26.20 and 27.80 days for males and 31.40, 32.40 and 36.80 days for females. All the results showed that Total developmental period and per cent larval development suggested that eggs of C. cephalonica as better food for C. carnea. [ABSTRACT FROM AUTHOR]

Trichogramma spp. ( Hymenoptera: Trichogrammatidae) parasitoids have been commonly used as biological control agents in insect pest management. Host quality is believed to influence parasitism, host preference, and suitability for parasitoids. To date, limited studies have compared the parasitism of Trichogramma parasitoids on fertilized, unfertilized, and sterilized host eggs. Hence, we studied the performance of three Trichogramma egg parasitoids, Trichogramma japonicum Ashmead, Trichogramma chilonis Ishii, and Trichogramma leucaniae Pang & Chen, on fertilized, unfertilized, and ultraviolet ( UV)-irradiated fertilized ( UVF) eggs of rice moth, Corcyra cephalonica ( Stainton) ( Lepidoptera: Pyralidae). In a no-choice test, T. japonicum and T. leucaniae parasitized significantly more fertilized or UVF than unfertilized hosts, and T. chilonis parasitized significantly more UVF than either fertilized or unfertilized hosts. In a choice test, all three Trichogramma parasitoids parasitized UVF hosts the most, and unfertilized hosts the least. There were similar percentages of adult emergence and female progeny among fertilized, unfertilized, and UVF hosts for all three Trichogramma parasitoids, except that T. japonicum had significantly lower adult emergence on fertilized hosts. We also found that all three Trichogramma parasitoids developed slower on unfertilized hosts. Regardless of host treatments, T. leucaniae had the longest developmental time and T. chilonis had the shortest. We conclude that Trichogramma parasitoids prefer parasitizing UVF eggs of C. cephalonica without negative effects on their emergence and sex allocation. [ABSTRACT FROM AUTHOR]

Rice moth, Corcyra cephalonica (Stainton) has been widely used as an efficient alternative host for the mass rearing of many biocontrol agents. With aim to increase production competence, egg dosages required for the initiation of its rearing culture were assessed. Each Corcyra rearing box containing 2.5 kg of milled sorghum was charged with different volume of eggs, i.e., 0.33 cc, 0.25 cc, 0.20 cc, 0.167 cc, 0.143 cc and 0.125 cc eggs and different parameters like larval period, first day to adult emergence, moth emergence, eggs production in F1 generation and fecundity per female were worked out. The larval period varied from 42 to 54 days and it increased with increase in volume of eggs per box. First adult emerged after 58.4 days in boxes charged with 0.33 cc eggs, which was significantly higher than other dosages (46.3 to 51.9 days). Moth emergence period in rearing boxes varied from 38 to 56 days in different dosages. Moth production per box (899.8 moths) was significantly higher at egg dosage of 0.20 cc followed by 0.25 cc, wherein 821.3 moths emerged. Similarly, egg collection in F1 generation was also maximum (8.63 cc) in boxes with initial dosage of 0.20 cc eggs per box, resulting in 43.15 fold increase as compared to volume of eggs used initially. In conclusion, the studies suggested that the optimal inoculative eggs for rearing of C. cephalonica should be 0.20 cc/box, each having 2.5 kg of milled sorghum for maximizing its production competence. [ABSTRACT FROM AUTHOR]

In the present study, a riboflavin-binding hexamerin (RbHex) was cloned and characterized from the larval fat body of Corcyra cephalonica . The complete cDNA (2121 bp) encodes a 706-amino acid protein with a molecular mass ~ 82 kDa. Expression of RbHex 82 was predominant in fat body among larval tissues. Further, it is prominently expressed during the last instar larval development. Homology modeling and docking studies predicted riboflavin binding site of the hexamerin. Spectrofluorimetric analysis further confirmed riboflavin release from the hexamerin fraction. Quantitative RT-PCR studies demonstrated hormonal regulation of RbHex 82. 20-Hydroxyecdysone (20HE) had a stimulatory effect on its transcription whereas JH alone did not show any effect. However, JH in the presence of 20HE maintains the RbHex 82 expression which indicates the JH's role as a status quo factor. This study is the first to report the characterization of riboflavin-binding hexamerin in a lepidopteran pest. Further, the possibility of RbHex 82 as a pest control target is discussed. [ABSTRACT FROM AUTHOR]

Bracon hebetorSay shows high fecundity and natural rate of increase which makes it a promising enemy againstCorcyra cephalonica,a very common stored grain pest. The functional response of the parasitoid can determine potential of a species to act as a biocontrol agent; it defines parasitoid’s searching efficiency and provides an understanding of host–parasitoid interaction. The mean longevity of female parasitoids had no significant difference when maintained at different densities of host insects. However, progeny sex ratio was significantly affected when different host densities were maintained during its adult life. The net fecundity rate (R0) and total fecundity rate (Rt) were highest when host density was five hosts per reproductive chamber. The mean length of generation time (T.c.) was higher on host density one compared to other densities. The intrinsic rate of increase (rm) was highest when the host density was five and lowest on 20 hosts per reproductive chamber. Other life table parameters were also affected significantly. On the basis of life table statistics, we can say that this type of density-responsive behaviour can be considered to be the most stabilizing one. [ABSTRACT FROM AUTHOR]

Arylphorin hexamerins are one of the major insect storage proteins involved in diverse functions during metamorphosis. However, their regulation during development is not elucidated so far. In the present study, we documented 20-hydroxyecdysone (20E)-mediated regulation of arylphorin expression in the fat body of the stored grain pest, Corcyra cephalonica . Based on the differential developmental expression and 20E-induced transcriptional as well as translational level alterations of arylphorin, we isolated the 5′ upstream region of the gene to analyze regulatory motifs. Promoter motif analysis revealed the presence of ecdysone response element (ERE). Transient transfection studies showed the functionality of the ERE. Enzyme mobility shift experiments with radiolabelled, cold and mutated probes indicate ERE-nuclear factor binding. This study is the first to report transcriptional regulation of arylphorins by 20E in lepdopteran insect species. [ABSTRACT FROM AUTHOR]

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W olbachia 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 W olbachia 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 W olbachia strain from the rice moth C orcyra cephalonica (designated as w Ccep_ B_ BJ), which was shown to share multilocus sequence typing and W olbachia surface protein hypervariable region profiles with a cytoplasmic incompatibility ( CI)-inducing strain in supergroup B, but the phenotype w Ccep_ B_ BJ may induce needs to be determined. We thus transinfected it into the whitefly B emisia tabaci harbouring an A- W olbachia through nymphal microinjection. Fluorescent in situ hybridization demonstrated that w Ccep_ B_ BJ was successfully transinfected into B. tabaci and transmitted to offspring through host eggs. Reciprocal cross showed that w Ccep_ B_ BJ induced a strong bidirectional CI in the transinfected host without imposing a significant cost on female fecundity. Our results suggest that w Ccep_ B_ BJ may be a promising strain for biocontrol of B. tabaci, an important agricultural pest insect. [ABSTRACT FROM AUTHOR]

The study of the technical and economic aspects of rearing natural enemies is essential for its effective use as a biological control agent in the field. The aim of this study was to determine the cost of production of the parasitoid, Telenomus remus (Nixon; Hymenoptera: Platygastridae), reared in eggs of its natural host, Spodoptera frugiperda (J. E. Smith; Lepidoptera: Noctuidae), and the alternative host, Corcyra cephalonica (Stainton; Lepidoptera: Pyralidae). The insects were reared in accordance with their respective methodologies of laboratory rearing. The cost of production of this biocontrol agent is US$ 0.0004 when reared with S. frugiperda eggs and US$ 0.0002 with C. cephalonica eggs. [ABSTRACT FROM AUTHOR]

Culture ofSteinernemasp.was maintained onCorcyra cephalonicalarvae. Steinernemasp.(at 50, 500, 1000, 2500, 5000, 10,000 and 20,000 ij’s /500 g soil) was concomitantly inoculated with 500 J2ofMeloidogyne incognita/500 g soil to the eggplant seedlings in the pots filled with 4 kg sterilised soil. The simultaneous inoculation ofM. incognitawith either of the inoculum levels (1000, 2500, 5000 and 10,000 J3/500 g soil) ofSteinernemasp. significantly reduced the damage caused byM. incognitain terms of plant growth parameters, viz. plant length, dry weight, number of flowers and weight of fruits. Moreover, the highest improvement in plant growth parameters, viz. plant length, dry weight, number of flowers and weight of fruits, was recorded in plants inoculated with 5000 J3ofSteinernemasp./500 g soil followed by 2500, 1000 and 10,000 J3/500 g soil. The highest reduction in the reproduction factor and number of galls/root system was recorded in the plants treated with 5000 J3Steinernemasp./500 g soil followed by 2500, 1000 and 10,000 J3/500 g soil. Comparison of concomitant and sequential inoculations showed that the sequential inoculation (both prior and after) ofSteinernemasp. at different inoculum levels (1000, 2500, 5000, 10,000 and 20,000 ij’s/500 g soil) was more effective in the management of root-knot nematode than the concomitant inoculation. Therefore, the application ofSteinernemasp. might be useful for suppression of nematode pest on eggplant and may be used as an alternative for chemicals. [ABSTRACT FROM PUBLISHER]

The rearing of Telenomus remus (Nixon 1937) has been limited due to the difficulty of its development in its natural host, the eggs of Spodoptera frugiperda (J.E. Smith). Environmental conditions can strongly affect egg’s parasitoid rearing on factitious hosts; however, until now only the effects of temperature have been studied. The importance of relative humidity in T. remus parasitism is poorly understood; therefore, this study evaluated its parasitism on Corcyra cephalonica (Stainton, 1866) and S. frugiperda eggs under different humidity regimes. Lifetime parasitism and parasitism viability were higher on S. frugiperda eggs and did not differ among humidity regimes. However, these biological parameters were higher at 80% humidity than at both 40 and 60% humidity when T. remus was reared on C. cephalonica eggs. The sex ratio was always higher than 0.6 for all hosts and humidity regimes. Parental female longevity was only influenced by humidity when presented to C. cephalonica eggs: it was higher at 60 and 80% humidity. T. remus egg-to-adult period was longer in C. cephalonica eggs; however, no difference between humidity regimes was noted. In general, relative humidity affected T. remus development only when it was reared on C. cephalonica eggs. For this factitious host, 80% humidity was shown to be appropriate for egg parasitoid rearing due to its better biological performance. [ABSTRACT FROM PUBLISHER]

Corcyra cephalonica Stainton is a notorious pest of stored cereals and cereal commodities in India as well as in other tropical and subtropical regions of the world. An experiment was conducted on extent of damage of C. cephalonica in maize under different storage structures during, 2010-2011, revealed that the maximum infested grain samples (61.53%) were recorded from grain stored in loose storage during June-July, 2011. Whereas, infested grain samples were not found from the grain stored in metal bin during November-December, 2010. The maximum weight loss (7.46%) was recorded in grain samples collected from loose storage in Udaipur district during June-July, 2011. No weight loss in grains were recorded in the samples collected from metal bin in Chittorgarh and Udaipur district during November-December 2010. In the quantitative and qualitative studies conducted in the selected districts observed that the maximum germination (78.00%) and protein content (8.60%) were recorded in the samples collected from metal bin in Chittorgarh district during November-December, 2010, while maximum carbohydrate content (72.00%) was recorded in maize samples collected from metal bin in Rajsamand district during November-December 2010. The minimum germination (62.00%) and carbohydrate content (66.50%) were recorded in maize samples collected from loose storage in Udaipur district; whereas, minimum protein content (6.70%) was recorded from loose storage in Chittorgarh district during June-July 2011. The studies conducted on efficacy of different grain protectants against C. cephalonica revealed that the highest larval mortality (82.20%), pupal mortality (10.00%) and minimum adult emergence (6.00%) were recorded in case of application neem leaf powder at 10g/kg seed, after 40 days of release. Application of wood ash at 15g/kg seed was found least effective. [ABSTRACT FROM AUTHOR]