Entomopathogenic fungus

We evaluated possible improvements to the mass rearing of the larval parasitoid Habrobracon hebetor (Say) (Hymenoptera: Braconidae) on irradiated host wax moth Galleria mellonella L. and Indian meal moth Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) larvae. The use of irradiated G. mellonella and P. interpunctella larvae at the dose of 150 Gy proved useful for enhancing the parasitism and adult emergence of H. hebetor due to the absence of negative repercussions on parasitoid development. Overall, parasitism was increased as the host larvae was irradiated with higher doses, while significantly higher parasitism was recorded at 150 and 300 Gy compared to lower doses. The female parasitoids preferred the irradiated larvae and significantly higher numbers of larvae were parasitized compared with non-irradiated larvae. The results also showed that irradiated larvae of G. mellonella served better as hosts for H. hebetor as compared with irradiated larvae of P. interpunctella. The implementation of these findings would be helpful for improving the mass production of parasitoids and the effectiveness of releases of biocontrol agents for the control of stored product pests.

In this study, the endophytic capacity of B. bassiana was determined for two barley (Hordeum vulgare) varieties, Josefa and Esmeralda, inoculated with a seedling immersion at three different concentrations (1 × 10 6 , 1 × 10 7 and 1 × 10 8 conidia/mL). Seedling length and chlorophyll content were found to be not affected when inoculated with the entomopathogenic fungus, in both barley varieties. However, the colonisation percentage was found to be significantly lower with the inoculum concentration 1 × 10 6 conidia/mL for both barley varieties (P < 0.05) when compared to the other concentrations. Furthermore, a principal component analysis indicated that 96.23% of the variability in the data could be explained with two components. This analysis showed that the seedling length and chlorophyll content were positively correlated in both barley varieties for the 1 × 10 7 conidia/mL concentration. Likewise, a positive correlation was observed for colonisation percentage and treatment with 1 × 10 8 conidia/mL in the Josefa variety only. This is the first study in which the endophytic capacity of B. bassiana was evaluated in two different barley varieties, with the Josefa variety found to be the most susceptible.

The endophytic plant-fungi symbiotic relationship can be explored to improve cultivation of targeted medicinal plant species. The objective of this study was to assess the effects of the cultivation of chive (Allium schoenoprasum) in plant growth medium inoculated with the entomopathogenic fungus, Beauveria bassiana (Hypocreales). Twelve replicates of chive seedlings were exposed to B. bassiana inoculum formulated at concentrations of 0, 1 Â 10 5 , 1 Â 10 4 and 1 Â 10 3 conidia mL À1 in a completely randomized design. We assessed plant growth parameters, such as leaf number and plant height weekly and root length, leaf and root fresh and dry weights and secondary metabolites three weeks post-fungal inoculation. The fungus was re-isolated from some of the leaves and roots of the treated plants suggesting that the fungus successfully colonized the plant tissue. Generally, the results indicated that the fungal inoculation had minimal effect on most of the growth parameters assessed in relation to the control. Remarkably, plants exposed to the fungus recorded greater (p < 0.05) total alkaloid, ranging from 2.98 -3.76 mg atropine equivalent (AE)/g dry weight (DW) compared to the control plants (1.96 mg AE/g DW) for the leaves. This study demonstrated that endophytic fungi could be used to improve the yield of active chemical constituents in cultivated medicinal plants.

Laurel wilt is a disease threatening the avocado industry in Florida. The causative agent of the disease is a fungus vectored by ambrosia beetles that bore into the trees. Until recently, management strategies for the vectors of the laurel wilt fungus relied solely on chemical control and sanitation practices. Beneficial entomopathogenic fungi (EPF) are the most common and prevalent natural enemies of pathogen vectors. Laboratory experiments demonstrated that commercial strains of EPF can increase the mortality of the primary vector, , and potential alternative vectors, , and (Coleoptera: Curculionidae: Scolytinae). Our study provides baseline data for three formulated commercially-available entomopathogenic fungi used as potential biocontrol agents against , and The specific objectives were to determine: (1) the mean number of viable spores acquired per beetle species adult after being exposed to formulated fungal products containing different strains of EPF (, and ); and (2) the m...

Background: 'The fall armyworm, Spodoptera frugiperda', represents a significant threat to maize production, a major staple crop in Asian countries. Methods: In pursuit of more effective control of this insect pest, our study assessed the physiological and biochemical effects of the entomopathogenic fungus Metarhizium anisopliae against the larvae of S. frugiperda. Results: Results revealed that, following nine days of treatment, a high concentration of conidia (1.5x10 7 conidia/mL -1 ) was toxic to all stages of larvae (second to fifth instar), resulting in 97% mortality of the second instar, 89% mortality of the third instar, 77% mortality of the fourth instar, and 72% mortality of fifth instar. All larval instars were found to have dose-dependent mortality effects. Treated S. frugiperda larvae further displayed significant physiological, morphological, and behavioral changes. Here, treated larvae displayed significantly lower levels of acetylcholinesterase, a-carboxylesterase, and b-carboxylesterase enzyme activity when compared to control groups. Treated larvae underwent an outward morphological change as the result of a decrease in the exterior cuticle of the anal papillae and a demelanization of the interior cuticle. Treated larvae also exhibited abnormal feeding behaviors as a consequence of the negative impact of conidia treatment on the neuromuscular system. Investigation into the effect of M. anisopliae on the non-target organism, the earthworm Eudrilus eugeniae, revealed that M. anisopliae conidia did not produce significant pathogenicity following three days of treatment. Furthermore, histological analysis revealed no significant effect of the entomopathogenic fungi on the gut tissue of the non-target organism. This study highlights the potential of M. anisopliae in the control of S. frugiperda.

The food flavour additive octanoic acid (C8:0) is also a metabolite of the entomopathogenic fungus Conidiobolus coronatus, which efficiently infects and rapidly kills Galleria mellonella. GC-MS analysis confirmed the presence of C8:0 in insecticidal fraction FR3 extracted from C. coronatus filtrate. Topical administration of C8:0 had a dose-dependent effect on survival rates of larvae but not on pupation or adult eclosion times of the survivors. Topically applied C8:0 was more toxic to adults than larvae (LD100 for adults 18.33 ± 2.49 vs. 33.56 ± 2.57 µg/mg of body mass for larvae). The administration of C8:0 on the cuticle of larvae and adults, in amounts corresponding to their LD50 and LD100 doses, had a considerable impact on the two main defense systems engaged in protecting against pathogens, causing serious changes in the developmental-stage-specific profiles of free fatty acids (FFAs) covering the cuticle of larvae and adults and damaging larval hemocytes. In vitro cultures of G. mellonella hemocytes, either directly treated with C8:0 or taken from C8:0 treated larvae, revealed deformation of hemocytes, disordered networking, late apoptosis, and necrosis, as well as caspase 1-9 activation and elevation of 8-OHdG level. C8:0 was also confirmed to have a cytotoxic effect on the SF-9 insect cell line, as determined by WST-1 and LDH tests.

The interactions between entomopathogenic fungi and insects serve a classic example of a co-evolutionary arms race between pathogens and their target host. The cuticle, site of the first contact between insects and entomopathogenic fungus, is an important defensive barrier against pathogens. It is covered by a layer of lipids that appears to play a key role in these processes and cuticular free fatty acid (FFA) profiles are consider as a determinant of susceptibility, or resistance, to fungal infections. These profiles are species-specific. The cockroaches Blattella germanica (Blattodea: Blattidae) and Blatta orientalis (Blattodea: Ectobiidae) are unsusceptible to the soil fungus Conidiobolus coronatus (Entomophthorales: Ancylistaceae) infection, therefore we studied the profiles of FFAs in order to understand the defensive capabilities of the cockroaches. The fungus was cultivated for three weeks in minimal medium. Cell-free filtrate was obtained, assayed for elastase, N-acetylglucosaminidase, chitobiosidase and lipase activity, and then used for in vitro hydrolysis of the cuticle from wings and thoraces of adults and oothecae. The amounts of amino acids, N-glucosamine and FFAs released from the hydrolysed cuticle samples were measured after eight hours of incubation. The FFA profiles of the cuticle of adults, and the wings, thoraces and oothecae of both species were established using GC-MS and the results were correlated with the effectiveness of fungal proteases, chitinases and lipases in the hydrolyzation of cuticle samples. Positive correlations would suggest the existence of compounds used by the fungus as nutrients, whereas negative correlations may indicate that these compounds could be engaged in insect defence.

One group of promising pest control agents are the entomopathogenic fungi; one such example is Conidiobolus coronatus, which produces a range of metabolites. Our present findings reveal for the first time that C. coronatus also produces dodecanol, a compound widely used to make surfactants and pharmaceuticals, and enhance flavors in food. The main aim of the study was to determine the influence of dodecanol on insect defense systems, i.e. cuticular lipid composition and the condition of insect immunocompetent cells; hence, its effect was examined in detail on two species differing in susceptibility to fungal infection: Galleria mellonella and Calliphora vicina. Dodecanol treatment elicited significant quantitative and qualitative differences in cuticular free fatty acid (FFA) profiles between the species, based on gas chromatography analysis with mass spectrometry (GC/MS), and had a negative effect on G. mellonella and C. vicina hemocytes and a Sf9 cell line in vitro: after 48 h, almost all the cells were completely disintegrated. The metabolite had a negative effect on the insect defense system, suggesting that it could play an important role during C. coronatus infection. Its high insecticidal activity and lack of toxicity towards vertebrates suggest it could be an effective insecticide. In their natural environment, insects have to cope with a variety of microorganisms, and as such, have developed a complex and efficient defense system. The first line of defense is a cuticle formed of several layers, with an epicuticle on the outside, a procuticle underneath it and an epidermis beneath that. The epicuticular layer is covered by a wax barrier against water. About 70% of the cuticle is composed of proteins, with the remaining 30% being made up of chitin, lipids, chinons and phenols. The cuticle is covered with complex mixtures of nonpolar and polar compounds 1 , including various hydrocarbons, free fatty acids (FFAs), alcohols, waxes, glycerides, aldehydes and sterols. The FFA profile can differ between insect groups and even between developmental stages of the same species. In addition, some specific cuticular lipids may also have a role in defending against fungal invasion 2-4 , and the presence of antagonistic microbes, toxic lipids and cuticle phenolic compounds has been suggested to inhibit fungal growth . Cuticular fatty acids are known to have a profound effect on fungal growth and spore germination; for example, C. vicina larvae and pupae demonstrate remarkable resistance to mycosis, which has been attributed to fatty acid composition of their epicuticle . Insects employ multiple immune responses incorporating both humoral and cellular defense reactions. The humoral reactions include the production of antimicrobial peptides, reactive oxygen and nitrogen species, and the activation of the prophenoloxidase system, which regulates the coagulation and melanization of hemolymph. Cellular responses, on the other hand, are based around the phagocytosis of small pathogens such as bacteria and fungi, the encapsulation of pathogens such as parasitoids and nematodes, and nodulation by specific insect immune cells (hemocytes) .

The interaction between insect and fungus is characterised on the one hand by the parasite developing more effective strategies of host exploitation, and on the other, by the host mounting increasingly robust defences though Red Queen dynamics or coevolutionary arms races. Furthermore, depending on gene flow and differences in selection pressure between sites, both host and parasite may demonstrate local adaptation to their counterpart or develop more general resistance or offensive traits. As the cuticle is considered the first line of defence of the insect, changes in the FFA profile may well influence susceptibility or resistance to fungal invasion. Our findings indicate that Sarcophaga argyrostoma demonstrates stage-specific resistance to Conidiobolus coronatus infection and suggests that FFAs play a role in resistance to fungal infection in flesh flies. These findings not only increase our knowledge of the entomopatogenic potential of fungi, but also of the growing level of infection by C. coronatus in humans and other mammals. Also, the presented research suggests that FFAs demonstrate antifungal activity which may be helpful in designing new antifungal treatments.

One group of promising pest control agents are the entomopathogenic fungi; one such example is Conidiobolus coronatus, which produces a range of metabolites. Our present findings reveal for the first time that C. coronatus also produces dodecanol, a compound widely used to make surfactants and pharmaceuticals, and enhance flavors in food. The main aim of the study was to determine the influence of dodecanol on insect defense systems, i.e. cuticular lipid composition and the condition of insect immunocompetent cells; hence, its effect was examined in detail on two species differing in susceptibility to fungal infection: Galleria mellonella and Calliphora vicina. Dodecanol treatment elicited significant quantitative and qualitative differences in cuticular free fatty acid (FFA) profiles between the species, based on gas chromatography analysis with mass spectrometry (GC/MS), and had a negative effect on G. mellonella and C. vicina hemocytes and a Sf9 cell line in vitro: after 48 h, al...

The interactions between entomopathogenic fungi and insects serve a classic example of a co-evolutionary arms race between pathogens and their target host. The cuticle, site of the first contact between insects and entomopathogenic fungus, is an important defensive barrier against pathogens. It is covered by a layer of lipids that appears to play a key role in these processes and cuticular free fatty acid (FFA) profiles are consider as a determinant of susceptibility, or resistance, to fungal infections. These profiles are species-specific. The cockroaches Blattella germanica (Blattodea: Blattidae) and Blatta orientalis (Blattodea: Ectobiidae) are unsusceptible to the soil fungus Conidiobolus coronatus (Entomophthorales: Ancylistaceae) infection, therefore we studied the profiles of FFAs in order to understand the defensive capabilities of the cockroaches. The fungus was cultivated for three weeks in minimal medium. Cell-free filtrate was obtained, assayed for elastase, N-acetylglucosaminidase, chitobiosidase and lipase activity, and then used for in vitro hydrolysis of the cuticle from wings and thoraces of adults and oothecae. The amounts of amino acids, N-glucosamine and FFAs released from the hydrolysed cuticle samples were measured after eight hours of incubation. The FFA profiles of the cuticle of adults, and the wings, thoraces and oothecae of both species were established using GC-MS and the results were correlated with the effectiveness of fungal proteases, chitinases and lipases in the hydrolyzation of cuticle samples. Positive correlations would suggest the existence of compounds used by the fungus as nutrients, whereas negative correlations may indicate that these compounds could be engaged in insect defence.

Invertebrates are becoming more popular models for research on the immune system. The innate immunity possessed by insects shows both structural and functional similarity to the resistance displayed by mammals, and many processes occurring in insect hemocytes are similar to those that occur in mammals. The humoral immune response in insects acts by melanization, clotting and the production of reactive oxygen species and antimicrobial peptides, while the cellular immunity system is based on nodulation, encapsulation and phagocytosis. An increasingly popular insect model in biological research is Galleria mellonella, whose larvae are sensitive to infection by the entomopathogenic fungus Conidiobolus coronatus, which can also be dangerous to humans. One group of factors that modulate the response of the immune system during infection in mammals are heat shock proteins (HSPs). The aim of this study was to investigate whether infection by C. coronatus in G. mellonella hemolymph is accompanied by an increase of HSP90, HSP70, HSP60 and HSP27. Larvae (five-day-old last instar) were exposed for 24 hours to fully-grown and sporulating fungus. Hemolymph was collected either immediately after termination of exposure (F24) or 24 hours later (F48). The concentration of the HSPs in hemolymph was determined using ELISA. Immunolocalization in hemocytes was performed using fluorescence microscopy and flow cytometry. HSP90, HSP70, HSP60 and HSP27 were found to be present in the G. mellonella hemocytes. HSP60 and HSP90 predominated in healthy insects, with HSP70 and HSP27 being found in trace amounts; HSP60 and HSP27 were elevated in F24 and F48, and HSP90 was elevated in F48. The fungal infection had no effect on HSP70 levels. These findings shed light on the mechanisms underlying the interaction between the innate insect immune response and entomopathogen infection. The results of this innovative study may have a considerable impact on research concerning innate immunology and insect physiology.

Entomopathogenic fungi are of particular interest now as the likely source of a new class of insecticides. This interest stems from the fact that these organisms naturally present in the environment, in most cases selectively affect specifi c organisms, and metabolites produced by them do not pass into the food chain. Using naturally or artifi cially introduced organisms to reduce populations of arthropod pests, provide you more than ever the security of the consumers as well as crops and the environment. This is particularly important from the point of view of organic farming, in which there is a need to extend the scope of alternatives against harmful insects. Careful study of the selection of organisms used, as well as the methods of their application are necessary for the effi cient and safe prevent losses caused by the pests. Much attention is paid to these issues, with a view to both human health and reducing exposure to unintended infections other living organisms, non-target conservation measures. The aim of this study was to identify toxic metabolites from trichothecene group produced by the parasitic fungus Conidiobolus coronatus. The results of our study allow conclude that the T-2 toxin is present in C. coronatus extract. It was also shown that C. coronatus produced higher amount of trichothecenes when is grown on LB medium. The optimal temperature for production of both T-2 and HT-2 by C. coronatus was 20°C. However, the pH value is the same for grown of C. coronatus mycelium and trichothecenes production. In any of the tested extracts DON and NIV was not detected. Toxicity of C. coronatus homogenates and post-incubation fi ltrates to G. mellonela larvae and Sf9 cells was also determined.

The aim of this study was to identify the chemical compound methanol extract of entomopathogenic fungus Beauveria bassiana from insect walang sangit and the chemical compound roots of red chili plants that were able to stimulate the growth of chilli plants after being applied with entomopathogenic fungus   B. bassiana through seed immersion inoculation using GCMS method. The chemical compound identified as a growth booster in   B. bassiana fungus isolates from the insect walang sangit is an Acetic acid Ethanoic acid Ethylic acid Glacial acetic acid CH3COOH, Hexadecanoic acid, methyl ester (CAS) Methylpalmitate Uniphat A60, n-Hexadecanoic acid Hexadecanoic acid n-Hexadecoic acid Palmitic acid, Dianhydromannitol and Ergosta-5,7,22-trien-3-ol, (3.beta., 22E) - (CAS) Ergosterol (CAS), while the chili root contains Acetic acid Ethanoic acid Ethylic acid Glacials acetic acid CH3COOH, Hexadecanoic acid, methyl ester (CAS) Methyl palmitate Uniphat A60, n -Hexadecanoic acid Hexadecanoic acid...

Behavioural fever is a common response to immune challenge in ectotherms and confers survival benefits. However, costs accrue rapidly as body temperature rises. Thus, the magnitude of adaptive fever responses might reflect the balance of costs and benefits. We investigated behavioural fever in desert locusts, Schistocerca gregaria, infected with the entomopathogenic fungus Metarhizium acridum. We first tracked the time course of behavioural fever in infected locusts, demonstrating that body temperatures rose on the day following inoculation (day 1), and reached peak intensity on the day after that (day 2). Subsequently, the magnitude of fever responses varied during a day, and locusts tended to exhibit high-intensity fever responses in the mornings when basking was first possible. We speculate that this may have resulted from increased fungal load caused by unimpeded growth overnight when locusts could not fever. We next inoculated locusts with different M. acridum doses ranging fro...

Metarhizium anisopliae is a parasitic fungus on insects, and thus called entomopathogenic fungus. This fungus is used as a biological control agent for insect pests. Fungal propagation can be done using a variety of media. The purpose of this study was to analyze the growth of M. anisopliae on four types of media, with conidial density and viability as the growth parameters. This research was conducted at the Laboratory of Microbiology, Universitas Negeri Semarang. This study was an experimental research used a Completely Randomized Design (CRD) with one factor and four treatments: Control (PDA/Potato Dextrose Agar medium), Treatment I (ELSA/Extract Larvae Sucrose Agar medium), Treatment II (CWSA/Coconut Water Sucrose Agar medium), Treatment III (CWELSA/Coconut Water and Extract Larvae Sucrose Agar medium). The and results showed that there was an effect of growth media on the density and viability of M. anisopliae conidia. CWELSA media had the highest conidial density (2.91 x 108 c...

The compatibility of Beauveria bassiana isolate DEBI 002 (Atashgah) with fipronil, pyriproxyfen and hexaflumuron insecticides was assayed. To determine the impact of the insecticides on the germination of the fungal spore, different concentrations of the compounds were added to the culture medium (malt agar). In order to calculate the mycelial growth in different treatments, each colony diameter was measured and the spores were counted in the surface area to assess its sporulation. The results showed that pyriproxyfen at 1500 ppm and hexaflumuron at 80 ppm completely inhibited mycelial growth, while the inhibitory effect of fipronil at 1600 ppm remained at 76.6%. The inhibitory effect of lower concentrations of all three insecticides was between 10 and 20%. All tested insecticides inhibited the spore production between 80 to 100% at the highest concentrations without any significant differences. Pyriproxyfen at 400 ppm and hexaflumuron at all concentrations completely inhibited spore germination, with significant difference, comparing with the rest of treatments. The results indicate that hexaflumuron has the highest inhibitory effect on the spore germination and is not recommended to be used simultaneously with B. bassiana against the insect pests.

The performance of an autoinoculation device was evaluated in field cage experiments for control of Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), in French bean, Phaseolus vulgaris L. var. Samantha (Fabaceae). Treatments consisted of a fungus‐treated device with and without semiochemical (Lurem‐TR), and a fungus‐free device as control; the fungus used was Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae). The overall mean number of conidia acquired by a single insect was higher in the fungus‐treated semiochemical‐baited device than in the device without semiochemical: 5.0 ± 0.6 × 104 vs. 2.2 ± 0.4 × 104 conidia per insect. The overall thrips mortality was also higher in the semiochemical‐baited device than in the device without the semiochemical: 59.3 ± 3.9 vs. 41.7 ± 3.5%. Conidial viability was not affected in the M. anisopliae‐treated device without semiochemicals, 7 days after treatment, whereas it was considera...

Selectivity of Beauveria bassiana and Metarhizium anisopliae to Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) ABSTRACT -Trichogramma pretiosum Riley and the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae are effi cient biological control agents and are thought to be used jointly. In here, we investigated if these entomopathogens could have any side-effects on T. pretiosum. Therefore, 1 x 8 cards containing sterilized eggs of Anagasta kuehniella (Zeller) that were sprayed with 0.2 ml of B. bassiana or M. anisopliae (1.0 × 10 9 conidia/ml) were offered to a T. pretiosum female for 24h (30 cards/fungus = 30 replicates). Afterwards, females were isolated in glass tubes. The control group was sprayed with sterile distillated water + Tween 80 (0.01%). In addition, 60 cards with sterilized eggs of A. kuehniella were submitted to parasitism by females of T. pretiosum for 24h. Of these cards, 30 were sprayed with B. bassiana or M. anisopliae and 30 with distillated water + Tween 80 (0.01%), and observed daily until parasitoid emergence. Metarhizium anisopliae decreased parasitoid emergence and caused confi rmed mortality. Therefore, fi eld and semi-fi eld experiments should be conducted for a fi nal assessment of the side-effects of these entomopathogens on Trichogramma as a ways to develop a control strategy in which both can be used.

Ambient pH regulates the expression of virulence genes of Metarhizium anisopliae, but it was unknown if M. anisopliae can regulate ambient pH. Mutants of M. anisopliae altered in production of oxalic acid were evaluated for the interrelationship of ambient pH, buffering capacity added to media, growth, and generation of extracellular proteases and ammonia. Wild-type and acid-overproducing mutants [Acid(M)] grew almost as well at pH 8 as at pH 6, but acid-non-producing [Acid(N)] mutants showed limited growth at pH 8, indicating that acid production is linked to the ability to grow at higher pH. Production of ammonia by M. anisopliae was strongly stimulated by low levels of amino acids in the medium when cells were derepressed for nitrogen and carbon. Likewise, although Aspergillus fumigatus and Neurospora crassa produced some ammonia in minimal media, addition of low levels of amino acids enhanced production. Ammonia production by A. fumigatus, N. crassa and M. anisopliae increased the pH of the medium and allowed production of subtilisin proteases, whose activities are observed only at basic pH. In contrast, protease production by the Acid(M) mutants of M. anisopliae was greatly reduced because of the acidification of the medium. This suggests that alkalinization by ammonia production is adaptive by facilitating the utilization of proteinaceous nutrients. Collectively, the data imply that ammonia may have functions related to regulation of the microenvironment and that it represents a previously unconsidered virulence factor in diverse fungi with the potential to harm tissues and disturb the host's immune system.

This study determined the efficacy of the Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Hypocreales: Cordycipitaceae) alone or combined with the diatomaceous earth DEA (a mixture of DE + abamectin) against adults and larvae of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). DEA was evaluated at 50 ppm while the fungi at 1.6 × 10 5 , 1.6 × 10 6 , and 1.6 × 10 7 conidia/kg wheat). Mortalities were assessed after 7 or 14 days of exposure, while progeny reduction in adults after 30, 60, 90, or 120 days. The radial fungus growth was significantly affected by the dose of DEA. Mortalities were higher in the combined treatments compared to the application of DEA or B. bassiana alone for both larvae and adults. Larvae were more susceptible than adults in all treatments and exposure intervals. Insect survival and progeny production were recorded for four months. Significantly fewer progeny was noted on wheat treated with DEA + B. bassiana treatments compared with control. The maximum number of mycosed cadavers and the rate of sporulation were observed at the lowest dose of B. bassiana alone, followed by the higher doses gradually. These findings indicate that the DEA + B. bassiana combinations can efficiently control T. castaneum, providing long-term protection of wheat.

This study determined the efficacy of the Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Hypocreales: Cordycipitaceae) alone or combined with the diatomaceous earth DEA (a mixture of DE + abamectin) against adults and larvae of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). DEA was evaluated at 50 ppm while the fungi at 1.6 × 105, 1.6 × 106, and 1.6 × 107 conidia/kg wheat). Mortalities were assessed after 7 or 14 days of exposure, while progeny reduction in adults after 30, 60, 90, or 120 days. The radial fungus growth was significantly affected by the dose of DEA. Mortalities were higher in the combined treatments compared to the application of DEA or B. bassiana alone for both larvae and adults. Larvae were more susceptible than adults in all treatments and exposure intervals. Insect survival and progeny production were recorded for four months. Significantly fewer progeny was noted on wheat treated with DEA + B. bassiana treatments compared with control. The maximum ...

O uso de ácido ou extrato pirolenhoso, obtido através da condensação de vapores liberados durante o processo da queima da madeira para a produção de carvão, vem sendo recomendado e utilizado pelos agricultores no manejo fitossanitário da cultura do tomateiro. Entretanto, estudos visando avaliar a ação desses produtos no manejo fitossanitário são ainda limitados. Nesse sentido, este trabalho objetivou avaliar a ação do ácido pirolenhoso obtido de Eucalyptus grandis, Melia azedarach e Pinus caribaea sobre a traça-do-tomateiro Tuta absoluta, importante inseto-praga nos cultivos de tomate em todo o Brasil. Os tratamentos foram avaliados em relação à sobrevivência larval, preferência alimentar das larvas e oviposição dos adultos. Com base nos dados obtidos, constatou-se que o ácido pirolenhoso proveniente das três espécies arbóreas testadas não afeta o desenvolvimento, alimentação e oviposição de Tuta absoluta.

Background Entomopathogenic fungi (EPF) are the natural enemies of insect pests. Nevertheless, research on the use of EPF for simultaneous prevention of pest and disease agents on the same crop is limited. In this study, we explored the potential dual effects of three strains of the EPF Metarhizium anisopliae on the control of detrimental agents of Vitis vinifera L., including different developmental stages (larvae, pupae, and adult) of the insect pest Lobesia botrana and the phytopathogenic fungus Eutypella microtheca. Methods Laboratory pathogenicity trials were performed to examine the effects of the three M. anisopliae strains on the mortality rate of L. botrana. In addition, field trials were conducted to assess the biocontrol potential of one selected M. anisopliae strain on the larval stage of L. botrana. Moreover, inhibitory effects of the three EPF strains on E. microtheca growth were examined in vitro. Results All the M. anisopliae strains were highly effective, killing al...

Investigations were carried out towards the "Mass production of entomopathogenic fungi (Metarhizium anisopliae) using different grains as a substrate" at International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Hyderabad during 2016-17. The accomplishment of microbial control of insect pests, the successful mass production of the microbial agents in the laboratory significant availability of the pathogen is a primary requirement in the biocontrol programme. Metarhizium anisopliae is an entomopathogenic fungus which is used against a number of insect pests" management and very successful biopesticides in integrated pest management practices to reduces the cost of production and minimize the environment and public health hazard. To develop a proficient method for the deployment of this fungus as a bio control agent, various grains and liquid media such as Potato Dextrose Broth and Sabouraud"s Dextrose Broth were screened. Significantly highest conidial count (67.6 × 10 3 spores/ml) was observed on green gram followed by sorghum in 10 3 dilutions, the assessment fungus whereas SDB produced significantly higher spore production of the fungi. Highest conidial count (63.7 × 10 3 spores/ml) was observed on SDB media followed by PDB in 10 3 .

We are developing an autodisseminator ('dispenser') to inoculate Asian citrus psyllid with entomopathogens for the purpose of inducing epizootics in residential trees and abandoned groves, areas where chemical control is problematic. The dispenser prototype consisted of a bright yellow pleated tube coated with a spore formulation made from pulverized cotton burrs and blastospores of Isaria fumosorosea. Adult psyllids were released within an array of dispensers and potted citrus saplings in a greenhouse. After 24 h, they were collected from the foliage, surface sterilized, and placed in an incubator. A mean of 55% of the adults developed mycosis (n = 3 tests), demonstrating that the dispensers could cause primary infection. The potted plants used in the horizontal transmission tests were infested with immature psyllids; 27-35% of which became infected following contact with adults that had visited the dispensers (n = 2 tests). When mycosed adult cadavers with mature conidia were placed near immatures on the potted plants, over 90% of the immatures mycosed, indicating that conidia from the cadavers were highly contagious. On dispensers left in the greenhouse for three weeks, the infectivity of blastospores exposed to direct sunlight decreased by 46% after 7 d and by 60% after 20 d, while infectivity levels remained high in blastospores that were shaded. These results confirmed that that the basic dispenser design was sound with respect to attracting and infecting psyllids. It requires further modification to work effectively under ambient conditions, since exposure to direct sunlight decreased blastospore infectiveness over time.

Performance of different coloured sticky traps against aphids in Bt cotton was studied in a field
experiment conducted in factorial randomized block design (RBD) using RCH-578 BGII genotype at College of Agriculture, Latur Farm, Maharashtra during Kharif 2022-23. The mean data of aphids (Aphis gossypii) population on different coloured sticky traps recorded at 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98, 105, 112, 119, 126, 133, 140, 147 and 154 DAS indicated that yellow colour sticky traps attracted more aphid population (31.35 aphids/trap) followed by blue colour sticky trap (25.44 aphids/trap) while least count was observed on white colour sticky traps (20.59 aphid/trap).
Irrespective of colours, the trap installed at equal crop height recorded more number of aphids (27.86 aphids/trap) and least recorded at traps installed at ground level (24.35 aphids/trap). Interaction effect showed significant difference as yellow colour trap installed at equal crop height attracted more number of aphids (38.78 aphid/trap) and found to be superior compared to other colour traps and trap heights

Entomopathogenic fungi have been investigated for management of stored product pests as alternatives to chemical control. Beauveria bassiana is commonly considered and thus increasing its efficacy has also been studied. The purpose of this study is to evaluate the effect of passing two B. bassiana cultures (wild and singlespore cultures) through n-hexadecane and n-octocasane based media on Rhyzopertha dominica and Sitophilus oryzae adult mortalities. For each Petri plate, 2 ml of 10% alkane was spread, let to evaporate and fungus was inoculated. After sporulation, spores for pathogenicity tests were produced by solid fermentation method on rice. Pathogenicity tests were conducted by application of 500 ppm (w/w) spores in wheat on 20 adults at 25±2oC, 65±5 r.h. in darkness with five replications. The efficacy of wild culture towards R. dominica adults was enhanced in both treatments. Mortality in 7 days increased from 35% to 55 and 69% when n-hexadecane and noctocasane were used, res...

The sustainability of agroecosystems are maintained with agro-chemicals. However, after
more than 80 years of intensive use, many pests and pathogens have developed resistance to the
currently used chemistries. Thus, we explored the isolation and bioactivity of a chemical compound,
Precocene I, isolated from the perennial grass, Desmosstachya bipinnata (L.) Stapf. Fractions produced
from chloroform extractions showed suppressive activity on larvae of Spodoptera litura (Lepidoptera:
Noctuidae), the Oriental armyworm. Column chromatography analyses identified Precocene I
confirmed using FTIR, HPLC and NMR techniques. The bioactivity of the plant-extracted Dp-
Precocene I was compared to a commercially produced Precocene I standard. The percentage of
mortality observed in insects fed on plant tissue treated with 60 ppm Db-Precocene I was 97, 87 and
81, respectively, for the second, third and fourth instar larvae. The LC50 value of third instars was
23.2 ppm. The percentages of survival, pupation, fecundity and egg hatch were altered at sub-lethal
concentrations of Db-Precocene I (2, 4, 6 and 8 ppm, sprays on castor leaves). The observed effects
were negatively correlated with concentration, with a decrease in effects as concentrations increased.
Distinct changes in feeding activity and damage to gut tissues were observed upon histological
examination of S. litura larvae after the ingestion of Db-Precocene I treatments. Comparative analyses
of mortality on a non-target organism, the earthworm, Eisenia fetida, at equal concentrations of
Precocene I and two chemical pesticides (cypermethrin and monocrotophos) produced mortality
only with the chemical pesticide treatments.

Maize is one of the high yielding and most grown cereal crop in the world. Maize stem borer Chilo partellus is most destructive pest of maize in fields of Pakistan. Cypermethrin from pyrethroids group of insecticides is used to control Chilo partellus. Experiment was conducted to observe the percent damage of Chilo partellus using cypermethrin (synthetic pyrethroid). Percent damage of Chilo partellus was observed at low, standard and high concentrations. Replications used in this experiment were ten for each treatment. Observations were recorded after time interval on different dates to observe if resistance was found in stem borers and to observe the percent damage. Results found that low damage percentage was observed on high sprayed concentration fields, while medium percent damage was observed on medium sprayed concentration fields. And highest percent damage was observed on high sprayed concentration fields as compared to control. So these results explicitly reveal that Chilo p...

Compatibility of three native isolates of Beauveria bassiana [OP271760 (BTL1), OP290199 (BTL2) and OP292066 (PKDE)] with five commonly used insecticides (imidacloprid, chlorantranilprole, cypermethrin, thiamethoxam and spinosad) and three fungicides (carbendazim, copper oxychloride and hexaconazole) were tested to identify and incorporate the compatible strain(s) in IPM. The B. bassiana isolate PKDE was compatible with most insecticides commonly used in Kerala except quinalphos. There was more than 80 per cent growth when checking compatibility with chlorantraniliprole, imidacloprid, thiamethoxam and spinosad. The isolates, BTL1 and BTL2 showed slight compatibility with insecticides viz., chlorantraniliprole, imidacloprid, thiamethoxam and cypermethrin with 20-40 per cent growth. Spinosad was 90 to 100 per cent compatible with all three isolates of B. bassiana in the present study. Among fungicides, hexaconazole and carbendazim completely inhibited the growth of all three isolates, whereas copper oxychloride showed 89 per cent compatibility with the isolate PKDE.

Key words: Beauveria bassiana, biopesticide, compatibility, insecticides, fungicides, scoring

The field experiments were conducted at the College of Agriculture, Iroishemba, Imphal during Rabi seasons of 2016-17 and 2017-18 to study the bio-efficacy of two microbial insecticides each at three doses against the Cabbage butterfly (CB), Pieris brassicae Linnaeus and their effect on the yield of cabbage crop var. “Green Hero”. There was high incidence of P. brassicae in the experimental crop variety. The insect maintained mean incidence of 65.33 to 69.40 per cent leaf damage. Thus, this pest was considered as the regular and major pest among the various species of butterfly observed in cabbage during the investigation. The results on the efficacy of microbial insecticides each at three doses against P. brassicae revealed that all the insecticidal treatments resulted in significantly suppression of the pest incidence in both the experimental years. The pooled mean data of two years based on three applications of insecticide indicated that Green pacer (Metarhizium anisopliae) @ 15...

Background: Control of the major African malaria vector species continues to rely extensively on the application of residual insecticides through indoor house spraying or bed net impregnation. Insecticide resistance is undermining the sustainability of these control strategies. Alternatives to the currently available conventional chemical insecticides are, therefore, urgently needed. Use of fungal pathogens as biopesticides is one such possibility. However, one of the challenges to the approach is the potential influence of varied environmental conditions and target species that could affect the efficacy of a biological 'active ingredient'. An initial investigation into this was carried out to assess the susceptibility of insecticide-susceptible and resistant laboratory strains and wild-collected Anopheles arabiensis mosquitoes to infection with the fungus Beauveria bassiana under two different laboratory temperature regimes. Methods: Insecticide susceptibility to all four classes of insecticides recommended by WHO for vector control was tested on laboratory and wild-caught An. arabiensis, using standard WHO bioassay protocols. Mosquito susceptibility to fungus infection was tested using dry spores of B. bassiana under two temperature regimes (21 ± 1°C or 25 ± 2°C) representative of indoor conditions observed in western Kenya. Cox regression analysis was used to assess the effect of fungal infection on mosquito survival and the effect of insecticide resistance status and temperature on mortality rates following fungus infection. Results: Survival data showed no relationship between insecticide susceptibility and susceptibility to B. bassiana. All tested colonies showed complete susceptibility to fungal infection despite some showing high resistance levels to chemical insecticides. There was, however, a difference in fungus-induced mortality rates between temperature treatments with virulence significantly higher at 25°C than 21°C. Even so, because malaria parasite development is also known to slow as temperatures fall, expected reductions in malaria transmission potential due to fungal infection under the cooler conditions would still be high. Conclusions: These results provide evidence that the entomopathogenic fungus B. bassiana has potential for use as an alternative vector control tool against insecticide-resistant mosquitoes under conditions typical of indoor resting environments. Nonetheless, the observed variation in effective virulence reveals the need for further study to optimize selection of isolates, dose and use strategy in different eco-epidemiological settings.

Insect-killing fungi such as Beauveria bassiana are being evaluated as possible active ingredients for use in novel biopesticides against mosquito vectors that transmit malaria. Fungal pathogens infect through contact and so applications of spores to surfaces such as walls, nets, or other resting sites provide possible routes to infect mosquitoes in and around domestic dwellings. However, some insects can detect and actively avoid fungal spores to reduce infection risk. If true for mosquitoes, such behavior could render the biopesticide approach ineffective. Here we find that the spores of B. bassiana are highly attractive to females of Anopheles stephensi, a major anopheline mosquito vector of human malaria in Asia. We further find that An. stephensi females are preferentially attracted to dead and dying caterpillars infected with B. bassiana, landing on them and subsequently becoming infected with the fungus. Females are also preferentially attracted to cloth sprayed with oil-formulated B. bassiana spores, with 95% of the attracted females becoming infected after a one-minute visit on the cloth. This is the first report of an insect being attracted to a lethal fungal pathogen. The exact mechanisms involved in this behavior remain unclear. Nonetheless, our results indicate that biopesticidal formulations comprising B. bassiana spores will be conducive to attraction and on-source visitation by malaria vectors.

Background: Insecticide resistance is seriously undermining efforts to eliminate malaria. In response, research on alternatives to the use of chemical insecticides against adult mosquito vectors has been increasing. Fungal entomopathogens formulated as biopesticides have received much attention and have shown considerable potential. This research has necessarily focused on relatively few fungal isolates in order to 'prove concept'. Further, most attention has been paid to examining fungal virulence (lethality) and not the other properties of fungal infection that might also contribute to reducing transmission potential. Here, a range of fungal isolates were screened to examine variation in virulence and how this relates to additional pre-lethal reductions in feeding propensity. Methods: The Asian malaria vector, Anopheles stephensi was exposed to 17 different isolates of entomopathogenic fungi belonging to species of Beauveria bassiana, Metarhizium anisopliae, Metarhizium acridum and Isaria farinosus. Each isolate was applied to a test substrate at a standard dose rate of 1×10 9 spores ml -1 and the mosquitoes exposed for six hours. Subsequently the insects were removed to mesh cages where survival was monitored over the next 14 days. During this incubation period the mosquitoes' propensity to feed was assayed for each isolate by offering a feeding stimulant at the side of the cage and recording the number probing. Results and conclusions: Fungal isolates showed a range of virulence to A. stephensi with some causing >80% mortality within 7 days, while others caused little increase in mortality relative to controls over the study period. Similarly, some isolates had a large impact on feeding propensity, causing >50% pre-lethal reductions in feeding rate, whereas other isolates had very little impact. There was clear correlation between fungal virulence and feeding reduction with virulence explaining nearly 70% of the variation in feeding reduction. However, there were some isolates where either feeding decline was not associated with high virulence, or virulence did not automatically prompt large declines in feeding. These results are discussed in the context of choosing optimum fungal isolates for biopesticide development.

Metarhizium anisopliae complex are globally ubiquitous soil-inhabiting and predominantly insect-pathogenic fungi. The Metarhizium genus contains species ranging from specialists, such as Metarhizium acridum that only infects acridids, to generalists, such as Metarhizium anisopliae, Metarhizium brunneum, and Metarhizium robertsii that cause disease in a broad range of insects and can also colonize plant roots. There is little information available about the susceptibility of Metarhizium species to clinical and nonclinical antifungal agents. We determined the susceptibility profiles of 16 isolates comprising four Metarhizium species with different ecological niches [M. acridum (6), M. ansisopliae (6), M. anisopliae sensu lato (1), M. brunneum (1), and M. robertsii (2)] to seven clinical (amphotericin B, ciclopirox olamine, fluconazole, griseofulvin, itraconazole, tebinafine, and voriconazole) and one non-clinical (benomyl) antifungal agents. All isolates of the specialist M. acridum were clearly more susceptible to most of the antifungals (the only exceptions were griseofulvin and terbinafine) than the isolates of the generalists M. anisopliae sensu lato, M. brunneum, and M. robertsii. All the isolates of M. anisopliae, M. brunneum, and M. robertsii were resistant to fluconazole [Minimal Inhibitory Concentration (MIC) >100 µg mL -1 ] and some isolates were also resistant to amphotericin B (MICs ranging from 1 to 70 µg mL -1 ). Differences in susceptibility profiles of the Metarhizium species were discussed in light of their diverse ecological niches. The marked differences in the susceptibility profiles between the specialist M. acridum and the generalist Metarhizium species suggest that this characteristic is associated with their different ecological niches, and may assist in devising rational treatments (i.e., selecting more effective antifungals) for the rare cases of mycoses caused by different Metarhizium species.

A non-autoclaved solid diet was used to evaluate the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) strain NI8 and the insect growth regulator novaluron (Diamond® 0.83EC insecticide) for control of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae). The diet was composed of toasted wheat germ, ground lima bean meal, soy flour, yolk of chicken eggs, inhibitor, and agar. It was prepared in one step by blending the ingredients in boiling water. The diet was used to bioassay L. lineolaris from the second instar to the adult stage. Fourth and fifth instars and adults of L. lineolaris were more susceptible than second and third instars to infection by B. bassiana, whereas second, third, and fourth instars had higher mortality than fifth instars 10 days after exposure to novaluron. No effects on longevity were observed in adults treated with novaluron when compared with the control, but longevity was significa...

Metarhizium is an entomopathogenic fungus widely employed in the biological control of arthropods. Hemocytes present in the hemolymph of invertebrates are the cells involved in the immune response of arthropods. Despite this, knowledge about Rhipicephalus microplus hemocytes morphological aspects as well as their role in response to the fungal infection is scarce. The present study aimed to analyze the hemocytes of R. microplus females after Metarhizium robertsii infection, using light and electron microscopy approaches associated with the cytotoxicity evaluation. Five types of hemocytes (prohemocytes, spherulocytes, plasmatocytes, granulocytes, and oenocytoids) were described in the hemolymph of uninfected ticks, while only prohemocytes, granulocytes, and plasmatocytes were observed in fungusinfected tick females. Twenty-four hours after the fungal infection, only granulocytes and plasmatocytes were detected in the transmission electron microscopy analysis. Hemocytes from fungus-infected tick females showed several cytoplasmic vacuoles with different electron densities, and lipid droplets in close contact to low electron density vacuoles, as well as the formation of autophagosomes and subcellular material in different stages of degradation could also be observed. M. robertsii propagules were more toxic to tick hemocytes in the highest concentration tested (1.0 × 10 8 conidia mL -1 ). Interestingly, the lowest fungus concentration did not affect significantly the cell viability. Microanalysis showed that cells granules from fungus-infected and uninfected ticks had similar composition. This study addressed the first report of fungal cytotoxicity analyzing ultrastructural effects on hemocytes of R. microplus infected with entomopathogenic fungi. These results open new perspectives for the comprehension of ticks physiology and pathology, allowing the identification of new targets for the biological control.

Ultrafast transient absorption spectroscopy is used to investigate sub-nanosecond exciton dynamics in Cd x Hg (1Àx) Te alloy colloidal quantum dots. A bleach was observed at the band gap due to state-filling, the mono-exponential decay of which had a characteristic lifetime of 91 ± 1 ps and was attributed to biexciton recombination; no evidence of surface-related trapping was observed. The rise time of the bleach, which is determined by the rate at which hot electrons cool to the band-edge, ranged between 1 and 5 ps depending on the pump photon energy. Measuring the magnitude of the bleach decay for different pump fluences and wavelengths allowed the quantum yield of multiple exciton generation to be determined, and was 115 ± 1% for pump photons with energy equivalent to 2.6 times the band gap.

Hemocytes, cells present in the hemocoel, are involved in the immune response of arthropods challenged with entomopathogens. The present study established the best methodology for harvesting hemocytes from Rhipicephalus microplus and evaluated the number of hemocytes in addition to histological analysis from ovaries of fungus-infected females and tested the virulence of GFP-fungi transformants. Different centrifugation protocols were tested, and the one in which presented fewer disrupted cells and higher cell recovery was applied for evaluating the effect of Metarhizium spp. on hemocytes against R. microplus. After processing, protocol number 1 (i.e., hemolymph samples were centrifuged at 500×g for 3 min at 4 °C) was considered more efficient, with two isolates used (Metarhizium robertsii ARSEF 2575 and Metarhizium anisopliae ARSEF 549), both wild types and GFP, to assess their virulence. In the biological assays, the GFP-fungi were as virulent as wild types, showing no significant ...

Rhipicephalus microplus is an important tick in tropical regions due to the high economic losses caused by its parasitism. Metarhizium anisopliae and Beauveria bassiana are well-known entomopathogenic fungi that can afflict R. microplus ticks. The development of new targets and strategies to control this parasite can be driven by studies of this tick's physiology. Recently, it was reported that when exposed to adverse physiological conditions, ticks can activate fermentative pathways, indicating transition from aerobic to anaerobic metabolism. Nevertheless, the precise mechanism by which entomopathogenic fungi influence R. microplus metabolism has not been clarified, limiting understanding of the tick-fungus association. Thus, the present study aimed to evaluate the effect of infection of ticks by M. anisopliae and B. bassiana on the amount of selected carboxylic acids present in the hemolymph, enabling increased understanding of changes previously reported. The results showed preservation in the concentrations of oxalic, lactic, and pyruvic acids in the hemolymph 24 and 48 h after dropping from cattle; while there were variations in the concentration of these carboxylic acids after infection of female ticks to M. anisopliae and B. bassiana. Significant increases were observed in the concentration of oxalic and lactic acids and significant reduction of pyruvic acid for both observation times (24 and 48 h) after infection by entomopathogenic fungi. These results indicate that B. bassiana and M. anisopliae infection alters the basal metabolism of R. microplus females, resulting in the activation of fermentative pathways.

Background: Mosquito-borne diseases affect millions of people. Chemical insecticides are currently employed against mosquitoes. However, many cases of insecticide resistance have been reported. Entomopathogenic fungi (EPF) have demonstrated potential as a bioinsecticide. Here, we assessed the invasion of the EPF Beauveria bassiana into Aedes aegyptilarvae and changes in the activity of phenoloxidase (PO) as a proxy for the general activation of the insect innate immune system. In addition, other cellular and humoral responses were evaluated. Methods: Larvae were exposed to blastospores or conidia of B. bassiana CG 206. After 24 and 48 hours, scanning electron microscopy (SEM) was conducted on the larvae. The hemolymph was collected to determine changes in total hemocyte concentration (THC), the dynamics of hemocytes, and to observe hemocyte-fungus interactions. In addition, the larvae were macerated to assess the activity of PO using L-DOPA conversion, and the expression of antimicr...

The suppressive ability of entomopathogenic fungus Beauveria bassiana alone and in combination with diatomaceous earth (DE) was studied against the larvae of Indian meal moth, Plodia interpunctella (Hübner) (Lep., Pyralidae). This study clearly showed that simultaneous use of B. bassiana and DE against larvae of P. interpunctella, not only could reduce the required concentration of fungal conidia or DE, but also could shorten the time need for showing insecticidal effects. The LC50 value of fungus at 7 d after treatment was 9.8 × 10 5 conidia mg −1 diet. Larvae showed a dose response to B. bassiana, and the addition of diatomaceous earth at 500 and 2000 ppm resulted in a significant increase in mortality. Larval mortality reached to the maximum of 28.3% and 71.7% after 7 d exposure to 500 and 2000 ppm DE concentrations, respectively. The LC50 value for B. bassiana in the presence of DE 500 ppm was 4.6 × 10 4 con. mg −1 diet and of DE 2000 ppm was 1.65 × 10 3 con. mg −1 diet. According to our results, B. bassiana and DE can be considered as two suitable candidates for integration into IPM strategy.

The tobacco cutworm or cotton leafworm, Spodoptera litura is considered an important pest in the Asian tropics and other temperate and tropical environments which cause loss of yields and productivity of more than 350 host species. The use of fungal strains as biological control agents to complement chemical techniques has achieved great success. This study assesses the use of indigenous entomopathogenic fungus (IBA5 & IBC6) in Kabirdam district of Chhattisgarh, India as a potential biopesticide to improve integrated pest management practices in the region. The mortality rate of IBA5 (Penicillium spp.) was 96.66% in the third stage and 80% in the fourth stage, while the efficacy of IBC6 (Fusarium spp.) was relatively lower, with 73.33% and 50% mortality, respectively. The incubation period was 10 days. Phylogenetic analysis identified IBA5 as belonging to Penicillium citrinum IBA5VYT, and these results were observed at a spore concentration of 1 × 10 7 spores/ml. Further investigation of the effectiveness of P. citrinum IBA5VYT against 3rd and 4th instar larvae of S. litura resulted in LC50 values of 4.5×10 4 spores/ml and 4.2×10 5 spores/ml, LC90 values of 1.6×10 6 spore/ml and 2.1×10 7 spores/ml, and LT50 values 121 hours and 134 hours. These results highlight the forte and effectiveness of P. citrinum against different larval stages of tobacco caterpillars and highlight the robustness and effectiveness of P. citrinum IBA5VYT as an entomopathogenic fungus to address environmental problems.