Ephestia Kuehniella Research Articles

Juvenile socio-sexual experience determines lifetime sperm expenditure and adult survival in a polygamous moth, Ephestia kuehniella.

Male animals often adjust their sperm investment in response to sperm competition environment. To date, only a few studies have investigated how juvenile sociosexual settings affect sperm production before adulthood and sperm allocation during the first mating. Yet, it is unclear whether juvenile sociosexual experience (1) determines lifetime sperm production and allocation in any animal species; (2) alters the eupyrene : apyrene sperm ratio in lifetime ejaculates of any lepidopteran insects, and (3) influences lifetime ejaculation patterns, number of matings and adult longevity. Here we used a polygamous moth, Ephestia kuehniella, to address these questions. Upon male adult emergence from juveniles reared at different density and sex ratio, we paired each male with a virgin female daily until his death. We dissected each mated female to count the sperm transferred and recorded male longevity and lifetime number of matings. We demonstrate for the first time that males ejaculated significantly more eupyrenes and apyrenes in their lifetime after their young were exposed to juvenile rivals. Adult moths continued to produce eupyrene sperm, contradicting the previous predictions for lepidopterans. The eupyrene : apyrene ratio in the lifetime ejaculates remained unchanged in all treatments, suggesting that the sperm ratio is critical for reproductive success. Male juvenile exposure to other juveniles regardless of sex ratio caused significantly shorter adult longevity and faster decline in sperm ejaculation over successive matings. However, males from all treatments achieved similar number of matings in their lifetime. This study provides insight into adaptive resource allocation by males in response to juvenile sociosexual environment.

ASPECTOS BIOLÓGICOS DE Ceraeochrysa everes (NEUROPTERA: CHRYSOPIDAE) ALIMENTADA COM COCHONILHA-ROSADA-DO-HIBISCO

ABSTRACT The invasive pink hibiscus mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae), is a pest that threatens the production of fruits, vegetable, and ornamental plants in Brazil. It is a phytophagous insect with a wide range of hosts; thus, there is an increasing demand for sustainable environmental-friendly control methods, such as biological control. This study aimed to investigate biological parameters of Ceraeochrysa everes (Neuroptera: Chrysopidae) fed on 2nd instar nymphs of M. hirsutus and eggs of Ephestia (Anagasta) kuehniella (Zeller) (Lepidoptera: Pyralidae). The duration of the immature stages of C. everes was longer when the predator was fed on 2nd instar nymphs of M. hirsutus, compared to the control (E. kuehniella). The survival rate of immature C. everes was 82.5% and 100% when fed on 2nd instar nymphs of M. hirsutus and eggs of E. kuehniella, respectively. The type of food resource offered at the larval stage affected the pre-oviposition, oviposition, and post-oviposition periods and the longevity of C. everes females. Adult females C. everes from immature individuals fed an exclusive diet of E. kuehniella eggs had longer oviposition, fecundity (daily and total), fertility, and post-oviposition periods and longevity. Ceraeochrysa everes has the capacity for predation, development, and reproduction while having 2nd instar nymphs of M. hirsutus as food resource. Therefore, C. everes has a promising potential for controlling M. hirsutus.

Effects of population density on adult morphology and life-history traits of female Mediterranean flour moth, Ephestia kuehniella (Lepidoptera: Pyralidae)

Intraspecific competition and food shortage due to high population density during early life can have a profound effect on adult fitness. Organisms often mitigate negative effects of high population density by adjusting resource allocation to adult morphological and life-history traits. In Lepidoptera with short-lived adults that do not feed, it is predicted that females developed from dense larval aggregations invest more in reproduction and traits linked to offspring survival. Here, we investigated the effects of larval population density on adult morphology and life-history traits in the female Mediterranean flour moth, Ephestia kuehniella by raising larvae at a range of population densities. Adults from high population density (16 larvae per g of food) had smaller head, thorax, and forewing compared to other densities. The allometric slope of forewing length with body mass did not differ among population densities, indicating no changes in adult wing morphology at high population density. However, we found that females emerged from larvae at high population density had bigger abdomens relative to body mass, indicating resource investment in reproduction, probably to mitigate the negative effects of crowding on egg production. Ovipositor length did not differ among population densities, indicating conservation of resources to structures with egg-laying function that affect offspring survival. Taken together, these results suggest that female E. kuehniella responding to high larval population density invest relatively more in reproduction, a life-history strategy that could alleviate negative effects of population density on fitness. This study also highlights the importance of a species' reproductive strategy in its adaptive response to environmental conditions, which is relevant to many capital breeders dependent on larval resources for reproduction.

Effect of Different Wheat-Based Diets and Corn Meal Addition on Development Parameters of Ephestia kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae)

The expansion of Integrated Pest Management (IPM), including biological control, has had several positive consequences for the agricultural environment and participants in the production chain. To enable successful operation and applications of biological control, production of insects used for rearing natural enemies (parasitoids and predators) must be optimized to reduce time and costs and improve production both qualitatively and quantitatively. The present study evaluated the effect of wheat varieties, the main component of artificial diets for Ephestia kuehniella, on the reproductive performance and biological parameters of this flour moth, which is used for mass production of Trichogramma spp. (Hymenoptera: Trichogrammatidae) and other parasitoids and predators. Four varieties of wheat were compared: BRS 327, BRS Marcante, BRS Parrudo, and KBR, with and without the addition of corn E. kuehniella reared on 97% BRS 327 wheat flour + 3% nutritional yeast had the best biological parameters and substitution of corn for about half of the wheat increased the number of eggs per female.

Insecticidal effect of Eucalyptus globulus and Rosmarinus officinalis essential oils on a stored food pest Ephestia kuehniella (Lepidoptera, Pyralidea).

For the purpose of evaluating the local heritage of eastern Numidia, an ethnobotanical survey was conducted on a population located in the province (department) of El-Tarf (North-East of Algeria) on a frequency of use of two plants known in traditional health; Eucalyptus globulus (Myrtaceae) and Rosmarinus officinalis (Lamiaceae). After processing data, our results show a female dominance when using these plants on a fairly advanced age group (40 to 60 years old). These plants are used by the people at their fresh state and deem the leaf as the most used part for therapeutic and cosmetic purposes. Furthermore, steam baths and infusion remain the most widespread preparation methods. Most consumers use these plants to treat influenza, respiratory illnesses as well as diseases of the digestive tract. GC-MS of essential oils extracted from the plants studied disclose a dominance of the alcohols portrayed by the monoterpenes (42.73%), sesquiterpenes (32.6%) and oxides (10.48%) in E. globulus. Data also indicate a high content of oxides (38.11%) monoterpene alcohols (20.43%) and monoterpenes (19.70%) in R.officinalis. Toxicological contact tests were achieved on a store-products pest Ephestia kuehniella. The test results were assessed with E.globulus (LC50=0.013; LC95=0.081 µl/cm2) and R.officinalis (LC50=0.011; LC95=0.059 µl/cm2). The lethal time changes according to the dose used and the tested plant. In E.globulus, we observe (concentration: 0.005 µl/cm2; LT50=56.2 h), (Concentration: 0.01 µl/cm2; LT50=49.53h) and (Concentration: 0.04µl/cm2; LT50=20.93h). Whereas in R.officinalis, we recorded (Concentration: 0.005 µl/cm2; LT50=55.7h), (Concentration: 0.01µl/cm2; LT50=54.99 h) and (Concentration: 0.04µl/cm2; LT50=29.13 h). The bioinsecticide has also been administered by fumigation and underpins toxicity by the reduction of adults longevity in E.kuehniella with R.officinalis (LC50=4.03 µl/l air; LC95=14.73 µl/l air) and E.globulus (LC50=7.76 µl/lair; LC95=21.23 µl/l air). In addition, the tested plants show an outstanding repellent effect as long as E.globulus and R.officinalis essential oils respectively demonstrate a slightly repellent power at 42.22% (RD50=0.09 µl/cm2; RD95=0.24 µl/cm2) and repellent at 60.00% (RD50=0.06 µl/cm2; RD95= 0.35 µl/cm2) towards E.kuehniella adults. The plant resources represent a genuine reserve of bioactive molecules, which can create solutions to sustainable development issues. These plants might be the source of new molecules of combat against some pests in order to protect human health and safeguard the environment.

Effects of pyroligneous acid on life history and physiology of two pyralid pests of stored products

Natural products derived from plant materials, such as wood vinegar (pyroligneous acid; PA), have shown toxicity to insects in previous studies; however, the impact of this substance on physiology and life history of stored product insects is unknown. Thus, the current study aimed to determine the effects of PA on two prominent stored product moths, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) and Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae). LC50/24h values of PA were determined for both species and first instar larvae were fed on an artificial diet containing LC50 concentrations of PA for their entire life cycle. Final instar larvae were selected for biochemical analysis while life history parameters were assayed in female adults that emerged from treated larvae. In both species, significantly lower activities of digestive enzymes (α-amylase, protease, and lipase) and detoxifying enzymes (carboxylesterase, monooxygenase cytochrome P450, and glutathione S-transferase) were observed in treated larvae relative to untreated larvae. In contrast, antioxidant enzyme activities (superoxide dismutase, phenoloxidase, and ascorbate peroxidase) were significantly elevated in treated larvae compare to controls in both species. Moreover, larvae of both species tended to have lower levels of energy reserves, such as proteins, lipids, and carbohydrates, and adults exhibited reduced longevity, fecundity, and oviposition periods in comparison to untreated larvae. Finally, GC-MS analysis of the PA used for this study demonstrated that phenolic compounds and organic acids were the largest constituents. These results indicate that consumption of PA leads to the induction of to the antioxidant system, the inhibition of detoxification and digestion enzyme activities as well as reduced levels of energy reserves. Cumulatively, these effects resulted in reduced longevity and fecundity compared to control insects. This study expands our knowledge of the impacts of PA on physiology and life history for two prominent pests of stored products.

Effect of Different Constant Temperatures on Life History and Life Table Parameters of Trichogramma euproctidis (Hymenoptera: Trichogrammatidae).

Temperature has a profound effect on performance and behavior of egg parasitoids. Egg parasitoids are a well-known alternative for the control of lepidopterous pests. Selected life history parameters of Trichogramma euproctidis (Girault) (Hymenoptera: Trichogrammatidae), an established egg parasitoid species in Khuzestan- Southwest Iran, were appraised at eight constant temperatures (22.5, 25, 27.5, 30, 32.5, 35, 37.5, and 40°C) using Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as the host. We found significant effects of temperature on the number of parasitized eggs, development time, sex ratio, progeny’s longevity, and fecundity. T. euproctidis developed on E. kuehniella eggs at all temperatures tested, but performed best at 32.5°C. At this temperature, they parasitized the most eggs, produced the most female progeny, and had high rates of survival. Our findings revealed that temperature significantly affected the longevity of female progeny and fecundity of T. euproctidis. A life table analysis confirmed that temperature resulted in optimal effects on T. euproctidis life history. Net reproductive rate (R0) of T. euproctidis was different among the temperatures tested. The intrinsic rate of increase (r) was positively correlated with temperature from 22.5 to 32.5°C and then decreased from 35 to 40°C. Generation time (T) and doubling time (DT) decreased as temperature increased from 22.5 to 37.5°C and then increased at 40°C. These data suggest that this strain of T. euproctidis is adapted to high temperatures and harsh environmental conditions and has the potential to be used in integrated management programs in Southwest Iran.

Effect of the Amount of Ephestia kuehniella Eggs for Rearing on Development, Survival, and Reproduction of Orius laevigatus.

Simple SummaryEconomical mass rearing of natural enemies is pivotal for their use as augmentative biological control agents. To this end, the conditions for mass production have been widely investigated for different natural enemies, including the predator Orius laevigatus. The key component for cost optimization of production systems is the type and amount of diet supplied. In the case of O. laevigatus, Ephestia kuehniella eggs have proved to be nutritionally superior to other cheaper natural and artificial foods. Consequently, the current practice in industrial production is the use of these eggs as food. Therefore, there is a need to know the minimum amount of Ephestia eggs needed per individual leading to a cost reduction, which in turn will favor biological control adoption. In this study, we established a minimum of 1 and 3 Ephestia eggs per day for the first two nymphal instars, respectively, and 8 eggs per day for subsequent development until adulthood. Benefits and savings for industrial production of O. laevigatus and its use in biological control are discussed.Orius laevigatus is a key tool for the success of augmentative biological control programs in protected crops. This biological control agent is mass-reared feeding on eggs of Ephestia kuehniella. However, this factitious prey is expensive, accounting for a significant percentage of the rearing costs. Therefore, there is a need to optimize the amount of Ephestia eggs needed per individual leading to a cost reduction, which in turn will favor biological control adoption. This study investigated the effect of the amount of Ephestia eggs provided on the developmental and reproductive fitness of O. laevigatus. At least a daily supply of 1 and 3 Ephestia eggs was needed for optimal development of the first two nymphal instars, respectively, although for maximum survival, 1 egg was enough for both instars. For subsequent development until adulthood, a minimum of 8 eggs per day were needed to fully support growth, but only 3 eggs for optimal survival. Similarly, male body size was also maximized by feeding 8 eggs, but for maximum female body size 10 eggs per day were required. Oviposition rate of females increased with the daily number of Ephestia eggs provided, until a plateau was reached at 8 eggs/day. Benefits and savings for industrial production of O. laevigatus are discussed.

Is pollinivory in the omnivorous ladybird beetle Micraspis discolor (Coleoptera: Coccinellidae) symbiosis-dependent?

The ladybird beetle Micraspis discolor is a potential biological control agent in the rice ecosystems of Asia. Besides attacking a range of arthropod prey the ladybird also feeds on pollen. To explore the mechanism of pollinivory of M. discolor, we compared the transcriptomes and microbiomes of the ladybird when fed rape pollen versus insect foods (the aphid Aphis craccivora, the mealybug Planococcus citri or eggs of the Mediterranean flour moth Ephestia kuehniella). We also set out to identify putative cellulase genes and cellulolytic bacteria that might aid in pollen digestion. From the genome of M. discolor, we only identified glycoside hydrolase family 1 genes as candidate cellulase genes. However, these genes were not differentially expressed under the pollen-fed treatment as compared to the other diets. Transcriptome comparison among different diet treatments of M. discolor showed that differentially expressed genes were mainly related to nutrient metabolism, indicating differences in nutrient and antinutrient composition among the different diets. When comparing the microbiomes of M. discolor under different diet treatments, cellulolytic bacteria, like Siphonobacter aquaeclarae, were detected as discriminative biomarkers of pollen feeding. The findings from transcriptome and microbiome analyses indicate that cellulolytic bacteria might play a more important role than endogenous genes in pollen digestion by this ladybird beetle.

Cost-effective and efficient factitious prey for mass production of Neoseiulus cucumeris (Acari: Phytoseiidae): assessing its quality compared with natural prey

BackgroundUsing alternative diets for the mass production of phytoseiid predatory mites may facilitate their cost-effective rearing. Factitious prey is often used as an alternative food source for mass rearing of generalist phytoseiids. The generalist predator, Neoseiulus cucumeris (Oudemans), is a commercially available biocontrol agent against various pests. We assessed the suitability of two factitious prey, Ephestia kuehniella Zeller eggs and Tyrophagus putrescentiae (Schrank), as diets for long-term rearing (up to 30 generations) of N. cucumeris, when compared with a natural prey, Tetranychus urticae Koch.ResultsThe predator completed its development on all tested diets successfully. Under laboratory conditions, Tyrophagus putrescentiae could support the development and oviposition of the predator for up to 30 generations even better than its natural prey T. urticae. However, the eggs of E. kuehniella were not suitable for this predator because of the longer pre-adult period and adults failed to reproduce.ConclusionsSince rearing on T. putrescentiae for a long time had no adverse effects on the predator’s performance, this factitious prey could be considered as a suitable and cost-effective diet for mass production of N. cucumeris.

Changes in Functional and Numerical Responses of the Parasitoid WaspTrichogramma brassicae(Hymenoptera: Trichogrammatidae) Over 45 Generations of Rearing onEphestia kuehniella

AbstractWe assessed the functional and numerical responses of Trichogramma brassicae Bezdenko under long-term rearing (45 generations, G5-G45) on eggs of a common factitious host, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Under such long-term mass rearing, the function response of this parasitoid shifted from Type III (from G5 to G20) to Type II (from G25 to G45). The maximum attack rate (T/Th) (33.62 hosts/day) and the shortest handling time (0.7138 ± 0.0272 h) were recorded in G5. Also, G45 had the lowest attack rate (21.67 hosts/day) and longest handling time (1.1076 ± 0.0689 h). The handling time increased gradually over the generations (P reg <0.01, R2 = 0.903). The number of eggs laid by the parasitoid increased significantly with increased host density, but reached a plateau at very high densities. While no significant differences in daily parasitism were observed over 45 generations at densities of 2, 4, 8, and 16 available host eggs per wasp, there were significant differences in parasitism at host densities of 32, 64, and 128 eggs per wasp. T. brassicae females were more active and foraged more frequently in earlier generations (G5 to G20), which allowed wasps to parasitize more E. kuehniella eggs compared to later generations. Also, continuous mass rearing of T. brassicae negatively affected foraging behavior and the quality of wasps after G20. However, rejuvenation of the colony by adding field-collected parasitoids or rearing wasps on more suitable factitious hosts is strongly recommended to lower the negative effects of long-term mass rearing on quality of this parasitoid.

Study of mating effect, hosts range and competition with the parasitoid Bracon hebetor on some behavioral and biological aspects of larval parasitoid Goniosus sp

Laboratory studies was conducted to investigate effect of mating behavior on egg laying, host selection and competition with Bracon hebetor. The results showed that no differences in mating and egg laying behavior between mated and unmated females. number of egg laying were 90.67 egg per female of unmated and mated females respectively. However unmated female produce only males progeny.The parasitoid showed response to the larvae of different lepidopterous insects such as. Mediterranean flour moth, potato tuber warm, greater wax moth, tomato leafminer, Angoumois Grain Moth and lesser date moth. The parasitoid did not respond to the larvae of Corn stem borer and cotton bollworm (tomato fruitworm) .The results of competition study between the parasite Goniozus sp and B. hebetor indicates that the first parasite was more competitive and parasitism on the larvae of the host where the percentage of parasitism was 72.22% of the total larvae, while, the percentage of parasitism was 27.77% for the parasite B.hebetor.

Lethal, sublethal and transgenerational effects of insecticides labeled for cotton on immature Trichogramma pretiosum

The parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) is often released to manage lepidopteran pests in cotton crops. However, growers rely on multiple insecticide applications to manage cotton pests. A harmonious integration of control tactics is required for proper pest management, and the use of selective insecticides (i.e., those promoting effective pest control while causing little impact on natural enemies) fits within this scope. This study aimed to assess the lethal, sublethal and transgenerational effects of insecticides from varying chemical groups on T. pretiosum. The insecticides were sprayed on parasitized host [Ephestia kuehniella (Zeller), Lepidoptera: Pyralidae] eggs with developing T. pretiosum stages (egg-larva, prepupa, and pupa), and biological traits were assessed following adult emergence. Overall, pupae were more susceptible to insecticides. We found thiodicarb and chlorfenapyr to reduce F0 adult emergence in rates comparable to the positive control (methomyl). Adult F0 deformation was the highest on flupyradifurone-treated organisms, and both the F0 parasitism rate and female survival were reduced by the insecticides (except for teflubenzuron). The sex ratio (proportion female) was affected by thiodicarb and flupyradifurone. Transgenerational effects occurred on adult emergence, which was reduced on the offspring (F1) of thiodicarb, chlorfenapyr, and flupyradifurone treated T. pretiosum. In addition, thiodicarb decreased the F1 sex ratio (≤ 0.33) compared to the other compounds (sex ratio ≥ 0.45). These results indicate that teflubenzuron is the safest insecticide; the other insecticides are non-selective to T. pretiosum. Field and semifield studies are required to confirm the harmfulness of chlorfenapyr, flupyradifurone and thiodicarb toward T. pretiosum.

Comparison of the Parasitization of Chelonus inanitus L. (Hymenoptera: Braconidae) in Two Spodoptera Pests and Evaluation of the Procedure for Its Production.

Simple SummarySuccessful integrated pest management of horticultural crops requires the evaluation of natural enemies used in biological control. To improve the mass rearing of Chelonus inanitus (L.) in the factitious host Ephestia kuehniella Zeller, we investigated the influence of host age and number of females parasitizing simultaneously on quality parameters evaluated in the commercial production of biological control agents, such as overall rearing success, duration of life cycle and body size. Under semi-field conditions, we investigated how the competition among females impacted the parasitism success on important pests Spodoptera exigua (Hübner) and S. littoralis (Boisduval). For the parasitoid mass rearing optimization, mature eggs seem to be more convenient because they increased the female percentage in the offspring and shortened the parasitoid life cycle. Furthermore, a high number of females parasitizing simultaneously reduced the emergence of non-parasitized hosts. Under more realistic conditions, the parasitoid effectively controlled both pests, but S. exigua may be a more convenient host because the parasitoid offspring was much larger. With this research, we provide a foundation that aims to better manage these cosmopolitan, highly polyphagous pests that exhibit long-distance migratory potential, alongside the potential use of this natural enemy.Chelonus inanitus (L.) is an egg-larval parasitoid of noctuids Spodoptera exigua (Hübner) and S. littoralis (Boisduval), whose mass rearing or real potential has not been targeted yet. To improve the rearing in the factitious host Ephestia kuehniella Zeller, we investigated the influence of host age and number of females parasitizing simultaneously on the overall rearing success, the influence of host age on the life cycle, and the influence of host species on the parasitoid body size. The proportion of emerging C. inanitus was higher from young host eggs, but more females emerged from mature eggs. Under high parasitoid competition, we observed a reduction in non-parasitized hosts without reducing parasitoid emergence. The parasitoid life cycle was longer in females, but the mismatch between sexes was smaller in mature eggs. The parasitoid size was smaller in the factitious host than in the natural hosts. Under semi-field conditions, we investigated the competition among parasitoid females on the overall parasitism success. The reproductive parasitism was more successful in S. exigua than in S. littoralis, and the maximum emergence was reached with three and four females, respectively. The control of S. littoralis may be attributed to the high developmental mortality, a non-reproductive parasitism that is often underestimated.

Effects of dietary insect (Ephestia kuehniella) egg meal on growth performance and fattyacid profile of common carp (Cyprinus carpio)

The effects of mill moth (Ephestia kuehniella) egg meal (IEM) upon growth performance and fatty acid profile of common carp (Cyprinus carpio) (1.12 ± 0.01 g) were evaluated in triplicate groups for 12 weeks. Three isonitrogenous (35% CP) and isocaloric (17 MJ kg?1) diets were formulated replacing fishmeal with 0% (G-0), 50% (G-50), and 100% (G-100) IEM. The results of the trial indicated that G-50 had the highest growth performance values and a more efficient FCR (1.79). Replacement levels of IEM did not have any significant effect on survival. Total monounsaturated fatty acids (MUFA) were found to be statistically different for all diets, and Σ SFA in fish was decreased with the increasing IEM levels. The ratio of n3/n6 was higher in G-0 reflecting a better balance. The results suggested that 50% replacement of IEM with fishmeal enhanced growth performance in common carp without any adverse effect on fatty acid profile, but investigation of the long-term effects has still been needed.

Atividade inseticida de um inibidor de peptidase das sementes de Anadenanthera macrocarpa contra Anagasta kuehniella

ABSTRACT Protease inhibitors (PIs) are a part of the plant defense system and reduce the proteolytic activity of the digestive enzymes of insect pests. The current study aimed to isolate and characterize an inhibitor of trypsin (AmTI) within the seed of Anadenanthera macrocarpa (Benth) (Leguminosae-Mimosoideae). Moreover, we tried to assess the defense mechanism of the larvae of Anagasta kuehniella against this inhibitor. Protein seed extracts were purified using Sephadex G-50 and trypsin-Sepharose columns. Electrophoresis revealed the molecular weight of the inhibitor to be 25 kDa. The stability evaluation demonstrated that the inhibitor was not denatured at temperatures of up to 60 °C, pH 2-10, and concentrations of up to 100 mM dithiothreitol for one hour. The inhibitor reacted in a 1:1 ratio with bovine trypsin with an inhibition constant [Ki] = 2.517 ´ 10-8. Incorporating the inhibitor in a 1 mg per 100 mg proportion of artificial diet offered to A. kuehniella larvae led to a significant difference in the weight and survival of larvae of the fourth instar compared to the control. AmTI acted on the enzymatic activities of trypsin and chymotrypsin, not allowing until the fourth larval instar, A. kuehniella, to create adaptations against the inhibitor, as it had a simultaneous effect on larval weight and mortality. Therefore, a new trypsin inhibitor showing inhibitory activity against the digestive enzymes trypsin and chymotrypsin from A. kuehniella was isolated, indicating that these activities are correlated with the deleterious effects of this insect.

Can Trichogramma atopovirilia Oatman & Platner replaces Trichogramma galloi Zucchi for Diatraea saccharalis (Fabricius) control?

Studies on aggressiveness of parasitoids, as assessed by their parasitism against pests, used in biological-control programs are highly important to select the most suitable species and/or strain to control insect pests. The present study investigated whether the egg parasitoid Trichogramma galloi Zucchi, an efficient control agent for sugarcane borer Diatraea saccharalis (Fabricius) in Brazil, could be replaced by Trichogramma atopovirilia Oatman & Platner, a parasitoid easier to mass-produce, since it has been found parasitizing D. saccharalis eggs in the warmest region of Brazil and Argentina. Three strains of the genus Trichogramma were compared: T. atopovirilia (ATP strain) reared on a factitious host Anagasta kuehniella (Zeller); T. atopovirilia isoline ATP-I, reared on D. saccharalis eggs for six generations; and T. galloi, reared on A. kuehniella eggs. We measured parasitism of each strain for 72 h and for the entire life span, parasitism rate per cluster of D. saccharalis eggs, number of parasitoids emerged (parasitism viability), and parasitoid life span. The results confirmed that T. galloi is the best species for D. saccharalis control, showing higher control potential, since parasitism and emergence rate were higher for this species. Although T. atopovirilia ATP-I performed reliably in all parameters, T. galloi exceeded and was the most indicated for mass-rearing in control programs for sugarcane borer.

Isolation of Bacillus thuringiensis strains from Saudi Arabia soil and study of their potential efficiency against the lepidopteran pest Ephestia kuehniella

Insect pests represent a major threat to food crops and human health, and therefore have to be combated in several ways, including chemical methods. However, researchers demonstrated that these molecules are dangerous for the farmers, consumers and the environment in general. For this reason, scientists permanently searched environment friendly alternatives such as the use of the bacterium Bacillus thuringiensis classified as one of the best insect pathogens. This microorganism is known by its ability to produce two types of insecticidal proteins, Vegetative insecticidal proteins (Vip) and delta-endotoxins produced during vegetative and sporulation stages of growth, respectively. In the present study, 15 B. thuringiensis strains were isolated from soil collected from different regions in Saudi Arabia (Al Baha, Jeddah, Khulis and Yanbu). B. thuringiensis isolates were then classified according to the shape of their parasporal crystals identified under microscope and proteins content of these crystals. Delta-endotoxins efficiency of the different isolates was investigated and promising strains were identified as very active. After 5 days-treatment, B. thuringiensis isolates 14 and 7 killed Ephestia kuehniella larvae with low LC50 of about 59.18 and 65.67 mg/cm2, respectively. The results described in the present study proved that the new B. thuringiensis isolates could be of a great interest in the control of lepidopteran pests by using their delta-endotoxins in bioinsecticide formulations.

Isolation of Bacillus thuringiensis strains from Saudi Arabia soil and study of their potential efficiency against the lepidopteran pest Ephestia kuehniella

Isolation of Bacillus thuringiensis strains from Saudi Arabia soil and study of their potential efficiency against the lepidopteran pest Ephestia kuehniella

Entomopathogens as biological control of the mediterranean flour moth, Ephestia kuehniella (Lepidoptera: Pyralidae)

Mediterranean flour moth Ephestia kuehniella (Zeller, Lepidoptera: Pyralidae) is one of the most important insect pests that invade the stored grain of many grains around the world. Chemical control is a very preferred method in the fight of this pest. However, due to the economic, social and environmental damages of chemicals, the interest in biological control, which is an alternative method, is gradually increasing. Entomopathogens have very important in biological control and that cause desired infections in pests. Entomopathogens include many species such as viruses, bacteria, protists, fungi and nematodes. In recent years, entomopathogeic nematodes; Steinernema feltiae, Steinernema carpocapsae, Steinernema riobrave, Heterorhabditis bacteriophora, Heterorhabditis sp., Steinernema sp., and Xenorhabdus nematophila, entomopathogenic fungi; Paecilomyces fumosoroseus (=Isaria fumosorosea), Beuveria bassiana and Metarhizium anisopliae, entomopathogenic bacteria; Bacillus thuringiensis subsp. kurstaki, Photorhabdus temperata and Bacillus subtilis, entomopathogenic protists; Vairimorpha ephestiae, Leidyana ephestiae, Mattesia dispora and Mattesia oryzaephili, and virus; Nuclear Polyhedrosis Virus (NPV) were reported from E.kuehniella. In this review, it is aimed to evaluate the recent status of these entomopathogenic organisms found or tested for E. kuehniella