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Cauliflower is an essential vegetable crop globally, providing essential nutrition and income for millions of people. However, it is highly susceptible to various pests, resulting in a significant reduction in both quality and yield. The conventional solution to control these pests has been the use of chemical pesticides, but their usage has resulted in severe negative effects on the environment, human health, and non-target organisms. Therefore, it is crucial to explore alternative methods, such as biological control with microbials, to manage cauliflower pests sustainably. The study aimed to assess the effectiveness of different microbial agents for controlling Pieris brassicae and Plutella xylostella on cauliflower over two rabi seasons of 2020–2021 and 2021–2022. The microbial agents evaluated were Beauveria bassiana 1.0% WP at 1.50 and 1.75 kg/acre, Bacillus thuringiensis var kurstaki 0.5% WP at 600 g and 800 g/acre, Metarhizium anisopliae 1.0% WP at 1.50 and 1.75 kg/acre, and Spinosad 2.5 SC at 240 ml/acre. The results showed that B. thuringiensis var kurstaki 0.5% WP (800 and 600 g/acre) was the most effective treatment against P. brassicae and P. xylostella on cauliflower, followed by B. bassiana 1.0% WP (1.75 g/acre). These two treatments significantly reduced the population of the target pests on cauliflower crops compared to untreated control. Additionally, treatments with B. bassiana and M. anisopliae recorded the highest populations of natural enemies, including coccinellid beetles, spiders, syrphids, and Cotesia glomerate cocoon on cauliflower. Regarding yield, spinosad 2.5 SC was found to be at par with B. thuringiensis var kurstaki 0.5% WP (800 and 600 g/acre) during rabi seasons of 2020–2021 and 2021–2022. The study suggests that B. thuringiensis var kurstaki 0.5% WP (800 and 600 g/acre) can be a suitable alternative to chemical pesticides, against P. brassicae and P. xylostella on cauliflower. [ABSTRACT FROM AUTHOR]

Looper caterpillars including the Biston (= Buzura) suppressaria (Lepidoptera: Geometridae) and Hyposidra talaca (Lepidoptera: Geometridae), are recorded as major defoliating pests in tea [Camellia sinensis (L.) O. Kuntze], are responsible for a decline in tea bush quality, a decrease in yield, and extensive foliage deterioration. The hasty and unlawful usage of chemical pesticides for looper control has adverse effects, such as the deterioration of natural soil fertility, disturbance of beneficial plant-microbe interactions, and an elevated risk of pesticide resistance. Undesired pesticide residues are frequently detected in the final tea product as pesticides have been applied to eradicate looper caterpillars in tea crop. In the current investigation, spore suspensions of two entomopathogenic fungi, Beauveria bassiana (MG547581) and Metarhizium anisopliae (MG547580), have been employed in vitro to evaluate their effectiveness in controlling three distinct stages of the life cycle of looper caterpillar. The highest rates of microbial infection and pest mortality were measured in the prepupal stage of each pest during in vitro incubation studies and bioassay. Pest mortality up to 90% was recorded with a spore load of 3 × 107 cfu/mL at the prepupal stage, while mortality in adults was up to 70% and influenced by species variations. The lowest median lethal dose (LD50) values of M. anisopliae were recorded as 1.1 × 106 (prepupae), 1.9 × 106 (pupae) and 3.2 × 106 (adult) against H. talaca and against B. suppressaria both the entomopathogens showed equal LD50 values in all distinct stages like prepupae (5.3 × 105), pupae (3.2 × 106) and adult (7.6 × 104). Further, median lethal time (LT50) values increased gradually from prepupae, and pupae to adult, both in cases of H. talaca (3.69, 3.97 and 4.40 days in 3 × 107 cfu/mL of M. anisopliae) and B. suppressaria (4.30, 4.72 and 5.34 days in 3 × 107 cfu/mL of B. bassiana) due to entomopathogenesis. As eco-friendly and nonchemical options for tea looper caterpillar management appear to be limited, the current study explores putative microbial alternatives such as B. bassiana and M. anisopliae for the sustainable management of two significant defoliating pests of tea. [ABSTRACT FROM AUTHOR]

Four species of Trichoderma genius (T. harzianum, T. citrinoviride, T. viride and T. asperellum) and Metarhizium anisopliae were assessed for their effects on larval mortality and progeny production of Trogoderma granarium Everts (Coleoptera: Dermestidae). The fungal strains were tested at 2.0 × 106, 2.0 × 107, 2.0 × 108 and 2.0 × 109 spores/kg. The larval mortality of T. granarium was recorded after 7, 14 and 21 days of treatment. The emerged adults (F1) from treated larvae were counted after 30 days of treatment, while F2 and grain weight loss were examined after 80 days of treatment. In general, increasing of spore concentration of all fungal strains enhanced the larval mortality. After 21 of treatment, all fungal strains induced notable larval mortality particularly at the highest concentration (2.0 × 109 spores/kg) except T. viride (19.4%). The highest larval mortality was observed in treatments with M. anisopliae (82.1%) and T. citrinoviride (69.0%) at 2.0 × 109 spores/kg, respectively. Furthermore, all spore concentrations of tested fungi decreased the emerged adults (F1 and F2) with M. anisopliae, T. citrinoviride and T. harzianum being the most potent, particularly at 2.0 × 109 spores/kg. After 80 days, M. anisopliae and T. citrinoviride at 2.0 × 109 spores/kg induced the highest protection of wheat grains against larvae of T. granarium with weight loss of 0.7 and 1.3%, respectively. The outcomes of the present study indicate that the two fungi, M. anisopliae and T. citrinoviride are highly effective seed protectants against T. granarium and could be applied in the integrated pest management programs (IPM) of khapra beetle as effective biological control agents. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) is a major staple for the majority of the global population and plays a significant role in economic stability. Being a staple food, it is attacked by various insect pests mainly aphids. Rhpalosiphum padi and Shizaphis graminum are considered serious aphid pests of the wheat crop. An experiment was conducted to evaluate the insecticidal potential of Beauveria bassiana and Metarhizium anisopliae against aphid species. B. bassiana and M. anisopliae were tested at three same dose rates (1.05 × 1013, 0.52 × 1013 and 2.1 × 1013conidia /ml) against the aphid species both in laboratory and field settings. Under laboratory conditions, B. bassiana and M. anisopliae were applied at the same dose rate and data regarding the mortality of insects were recorded after 3, 5 and 7 days. In the field, treatments were applied three times with a 15-day interval between each application. B. bassiana@1.05 × 1013conidia /ml resulted in maximum mortality against R. padi (83.39%) than S. graminum (79.36%) under laboratory conditions after a 7-day interval. Similarly, under field conditions, the mortality rates were 69.33% for R. padi, and 66.34% for S. graminum after the third spray treatment. The results concluded that B. bassiana provides more effective control than M. anisopliae under both laboratory and natural conditions against R. Padi and S. graminum. [ABSTRACT FROM AUTHOR]

The fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae) is a key polyphagous pest because of the damage it causes to maize crops. The entomopathogenic fungi Metarhizium anisopliae AUMC2605 and Beauveria bassiana AUMC3563 were evaluated to manage S. frugiperda in the lab and field. Additionally, the toxicity of essential oils from Prunus amygdalus, Linum usitatissimum, Simmondsia chinensis, and Nigella sativa were detected against larvae S. frugiperda in the field. Using the drenches technique, the tested B. bassiana AUMC3563 and M. anisopliae AUMC2605 isolates were pathogenic to S. frugiperda and caused mortality ranging from 10.0 to 80.33%. The laboratory results indicated that B. bassiana AUMC3563 was more deadly than M. anisopliae AUMC2605. In the fifth instar larval stage S. frugiperda was not highly susceptible to the tested fungal isolates. However, the earlier instars larval of S. frugiperda were more susceptible to B. bassiana AUMC3563 and M. anisopliae AUMC2605. B. bassiana AUMC3563 caused the highest mortality of first, second, and third instar larvae at 5.6 × 107 conidia ml−1 in the laboratory. The field trial results also indicated that the entomopathogenic fungus B. bassiana AUMC3563 was more effective than M. anisopliae AUMC2605. These results assert the potentiality of entomopathogenic fungi and natural products as effective tools in sustainable and integrated pest management. [ABSTRACT FROM AUTHOR]

Indiscriminate use of synthetic pesticides by the brinjal growers in Assam has become a threat to biodiversity and consumer health. To find out the organic solution for managing brinjal pests, the efficacy of two entomopathogenic fungi (@1X108 spores/ml of water) was tested against naturally infested brinjal pests. The results revealed that Metarhizium anisopliae was more efficient in reducing the population of sucking pests like aphids (64.87%), jassids (57.74%), and white flies (63.80%). Meanwhile, Beauveria bassiana was found to be more effective against hadda beetle, reducing the population by 67.16% and also superior in reducing brinjal shoot and fruit borer infestations (percentage of shoot infestation = 9.34, percentage of fruit infestation by number = 11.73 and percentage of fruit infestation by weight = 14.32). Based on our earlier experimental result of dual culture assays against brinjal pathogens and compatibility tests among the biocontrol agents, a liquid consortial formulation with three best compatible biocontrol agents namely, Trichoderma harzianum, B. bassiana and M. anisopliae was prepared. A further field experiment was conducted at Assam Agricultural University, Jorhat and Krishi Vigyan Kendra, Barpeta, Assam to test the efficacy of six different Integrated Pests and Disease Management (IPDM) modules with the prepared consortia. The study showed that module-6 (seed treatment + seed bed treatment in nursery + soil application in main field + seedling dip treatment with consortia of biofertilizer, Rhizobium sp, Azotobacter sp strain 52, Azospirillum sp strain 71 and Bacillus sp strain 5 W + spraying of consortia) was the best for managing pests (aphid, jassid, hadda beetle and brinjal shoot and fruit borer) of brinjal. [ABSTRACT FROM AUTHOR]

The rice weevil, Sitophilus oryzae L. (Coleoptera: Curculionidae), is one of the major insect pests of stored wheat, maize, rice and cereal-based food products worldwide. Besides direct damages to stored food, S. oryzae has the ability to act as a vector of several fungal pathogens. Here, we collected strains of S. oryzae from rice storage facilities in Punjab, Pakistan, during 2020-22 and quantified fungal species on the bodies of weevils. A total of 54 isolates consisting of 17 species belonging to 10 genera were identified and morphologically characterized from different strains of S. oryzae. Overall, Aspergillus spp. were the most frequent (52%) in all the isolates followed by Alternaria spp. (13%), Metarhizium spp. (9%), Penicillium spp. (7%), Cladosporium sp. (5%), Rhizopus sp. (4%), Verticillium sp. (4%), Trichoderma sp. (2%) and Fusarium sp. (2%). The occurrence frequency of different fungal species was as follows: Aspergillus nidulans (7%), Aspergillus fumigatus (7%), Aspergillus flavus (15%), Aspergillus parasiticus (15%), Aspergillus oryzae (7%), Alternaria alternata (9%), Alternaria tenuissima (4%), Cladosporium cladosporioides (6%), Metarhizium flavoviride (4%), Metarhizium anisopliae (6%), Mucor racemosus (2%), Penicillium expansum (4%), Penicillium citrinum (4%), Rhizopus oryzae (4%), Verticillium lecanii (4%), Trichoderma harzianum (2%), and Fusarium oxysporum (2%). The Chi-square test of association revealed non-significant association of fungal species with different localities (p > 0.05). In conclusion, the results of the present study revealed that S. oryzae could play an important role in spreading and promoting fungal contamination and subsequent production of mycotoxins in stored foodstuff. [ABSTRACT FROM AUTHOR]

Synthetic pesticides are a considerable issue in both terrestrial and aquatic habitats. Green pesticides derived from fungi, provide an efficient tools and alternative to chemicals. Secondary metabolites from Metarhizium anisopliae were tested against major disease mosquitos such as, Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus, as well as two non-target species, Eudrilus eugeniae and Artemia nauplii. After 24 h of treatment, M. anisopliae derived chemical constituent produced low LC50 values, 54.678, 92.819, and 93.792 µg/ml on Aedes aegypti, for Anopheles stephensi, 80.933, 116.990 and 130.173 µg/ml, for Culex quinquefasciatus, 109.733, 196.540, 182.853 µg/ml in larvae, pupae, and adult, respectively. On the contrary, fungal metabolites are not hazardous to non-target species.. Midgut histology investigations revealed that M. anisopliae metabolites were less harmful to earthworms than chemical pesticides (Permethrin). The treatment of fungal crude extract exhibited minimal toxicity effects on gut tissues, normal epidermis, circular muscle, setae, mitochondrion, and intestinal lumen tissues. M. anisopliae crude metabolites showed a lower toxicity against the non-target species A. nauplii. Our results clearly shows minimal mortality rates were produced by the M. anisopliae derived chemical constituents, LC50 and LC90 values were, 455.947, 5098.233 μg/mL−1. No behavioral changes were observed during the treatment. The primary components of M.anisopliae crude extract identified by GC–MS studies were aucubin (14.356%) and 9, 12-Octadecadienoic acid (z,z)-(75.009%). The presence of key functional groups such as carboxylic acid, amides, and phenol groups was revealed by FT-IR spectral studies, which may be involved in mosquitocidal activity. [ABSTRACT FROM AUTHOR]

Biocontrol compared to chemical insecticides is an alternative to reduce the population size of an organism in an environmentally friendly way. Mixtures between plant extracts and microorganisms are an alternative to reduce mosquitoes´ resistance to the most commonly used insecticides. In this study, the effect of Metarhizium anisopliae was tested separately and in combination with Azadirachta indica seed extract against Anopheles albimanus larvae under laboratory conditions. Five fungal concentrations between 1 × 103 and 1 × 107 conidia/ml were tested for individual bioassays, and five concentrations between 0.1 and 1000 ppm neem extracts were used. The interaction between fungus and extract was tested at 1 × 103 conidia/ml, 1 × 104 conidia/ml and 1 × 105 conidia/ml with 1 ppm of A. indica extract in binary mixtures. Lethal concentrations 50 were 3.99 × 105 conidia/ml and 16 ppm for M. anisopliae and A. indica extract, respectively. The presence of 1 ppm of A. indica extract did not affect the germination of M. anisopliae conidia nor the fungus growth. Mixtures of 1 ppm A. indica extract and M. anisopliae conidia increased An. albimanus larvae mortality compared with each of these biocides alone and a synergistic effect was found. Results indicate that M. anisopliae and A. indica extract binary mixture is an excellent alternative for the biological control of An. albimanus larvae. [ABSTRACT FROM AUTHOR]

Tea Mosquito Bug, Helopeltis antonii Signoret is an emerging pest of guava which causes severe qualitative yield loss to the farmers. During its feeding on guava, it injects a toxin through its saliva, which causes necrotic spots in leaves, twigs and corky outgrowth over fruits. Two field trials were carried out during 2019–2020, to access the efficacy of bio-rationales against guava tea mosquito bug in the farmer's fields at Andipatti and Natham, Tamil Nadu, India. Regardless of locations, tea mosquito bug population reduction in Lecanicililum lecanii 106 CFU/ L at 5 g/ ml was higher followed by Metarhizium anisopliae 108 CFU at 8 g/ L. The efficacy of Azadirachtin 10,000 ppm at 2 ml/ L, NSKE 5% and pungam oil 3% were moderate. Neem oil 3% and fish oil rosin soap were highly ineffective. The efficacy of bio-rationals was much pronounced at 14 Day after Spraying (DAS) in the best treatments. From the present investigation it is evident that L. lecanii 106 CFU/ lit at 5 g/ ml was effective against H. antonii followed by M. anisopliae 108 CFU at 8 g/ lit. The efficacy of Azadirachtin 10,000 ppm at 2 ml/ lit, NSKE 5% and pungam oil 3% were moderate. [ABSTRACT FROM AUTHOR]

Metarhizium anisopliae and Isaria javanica represent an alternative as biological control agents for insect vectors in endemic areas with high prevalence and incidence of Chagas disease. The virulence of these fungi toward Meccus pallidipennis, insect vector of Trypanosoma cruzi, causative agent of Chagas disease was evaluated by their mortality and medium survival time (ST50) on five instar nymphs (N1, N2, N3, N4, N5) and adults of this vector. The virulence of both fungi was evaluated independently by ST50. Thirty µL of a conidial suspension (107 conidia/mL) from each fungus was applied on the insect pronotum, and mortality was reported every 24 h. Experiments were assayed three times for each insect stage and for each fungus. The mortality in all the nymphal stages (N1-N4) of M. pallidipennis with M. anisopliae was > 96% at day 9, except in N5 97% at day 12, and in the adult stage was 100% at day 10. In all nymph stages and adults, the mortality of M. anisopliae was higher than that of I. javanica. The ST50 of N5 and adults for I. javanica was 9.5 and 13 days, respectively, and in these same stages for M. anisopliae, ST50 was 8 and 9 days. M. anisopliae exhibited a higher virulence than I. javanica for the control of the triatomine M. pallidipennis. Both fungi can be a biological control alternative for regulating populations of M. pallidipennis in Chagas disease endemic areas. [ABSTRACT FROM AUTHOR]

Identification of insecticidal compounds from the entomopathogenic fungus Metarhizium anisopliae crude extract was performed by TLC and column fractionation. From the fractionation four fractions were separated and tested for larvicidal, pupicidal and adulticidal potential against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes. Among the four fractions the fraction-3 was most effective against larvae with LC50 values, 1.238, 1.300 and 2.899 for pupae, 1.440, 1.657, 2.593 and adult, 1.988, 2.037 and 4.086 µg/ml against Ae. aegypti, An. stephensi and Cx. quinquefasciatus at 24 h post treatment respectively. The effective fraction-3 were charectrized through FT-IR, UV–Vis spectroscopy, 13C-NMR and 1H-NMR, HPLC, and LC–MS analysis allowed to identifying the effective compound in fraction-3. Overall, the results confirmed the use of the fungus derived molecules as an active green pesticide against mosquito vectors of public importance and led to the identification of highly effective mosquitocidal products. In particular the toxic activity of aucubin far encompassed that of the large majority of earlier studied microbial insecticides, making this molecule an ideal candidate for the development of insecticides in the "real world". [ABSTRACT FROM AUTHOR]

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the most important cruciferous pests, severe economic damage. Microbial control is based on the reasoned use of pathogens to manage pest population levels. Metarhizium anisopliae (Ascomycota: Hypocreales) is one of the facultative insect pathogens; it is a good choice for that purpose. Conidia survival may be affected by several environmental factors or through chemical pesticides used to control pests. In this research, the efficiency of M. anisopliae IRN.1, when used alone or in combination with sub-lethal doses of lufenuron, flubendiamide and indoxacarb, against P. xylostella was studied. The effect of pesticides on the vegetative growth, conidial germination and fungus sporulation was then tested. The results indicated that the compatible formulation with M. anisopliae was indoxacarb. Further median lethal time (LT50) of the fungi combination with the sub-lethal concentration of indoxacarb was less than that of other treatments. The combined use of fungal and indoxacarb could be, thus, used simultaneously in the integrated management of P. xylostella. [ABSTRACT FROM AUTHOR]

Armyworm Spodoptera litura (Lepidoptera: Noctuidae) is a voracious pest with a wide host plants range. Synthetic insecticides are employed widely to control this pest leading to many ecological consequences. This necessitates looking for some biorational approaches to control this pest such as entomopathogenic fungi (EPF) and differential-chemistry insecticides which have different mode of action than the conventional insecticides. This study evaluated the insecticides (chlorantraniliprole, emamectin benzoate and lufenuron) and EPF (Beauveria bassiana and Metarhizium anisopliae) against 3rd instar larvae of S. litura using diet-incorporation and immersion methods respectively, alone and in binary combinations of the most effective treatments. Among differential-chemistry insecticides, chlorantraniliprole exhibited maximum larval mortality (24–100%) with minimum LC50 and LT50 values, followed by lufenuron (0–100%), while emamectin benzoate showed minimum larval mortality (0–68%) recorded at 24–96 h intervals. Among EPF, M. anisopliae showed significantly higher entomopathogenicity and caused 20–53% larval mortality than B. bassiana (5–35%) in 3–10 days post-exposure. Moreover, the binary combinations of M. anisopliae and chlorantraniliprole exhibited synergistic effect on S. litura larvae. It is concluded that chlorantraniliprole and M. anisopliae are effective biorational options exhibiting compatibility with each other which can be employed together against S. litura infestations and it will also aid to mitigate the insecticide resistance. However, field evaluations of these differential-chemistry insecticides along with EPF strains against insect pests and their impact on natural enemies constitute future perspectives of the study. [ABSTRACT FROM AUTHOR]

Two indigenous entomofungal strains each of Beauveria bassiana and Metarhizium anisopliae were tested for their pathogenic effect on Aak grasshopper, Poekilocerus pictus, Fabricus, 1775 (Orthoptera: Acrididea) under laboratory conditions. Among the four isolates tested, M. anisopliae ICAR-NBAIR Ma-4 and ICAR-NBAIR Ma-35 caused 100 and 90% mortality, respectively, whereas B. bassiana ICAR-NBAIR Bb-78 and ICAR-NBAIR Bb-45 showed 40 and 14% mortality, respectively. ICAR-NBAIR Ma-4 and ICAR-NBAIR Ma-35 isolates were further tested on eggs of grasshoppers which showed 72.7 and 59.8% mortality respectively. Dose and time mortality studies with ICAR-NBAIR Ma-4 showed LC50 value of 1.52 × 103 spores/ml and LT50 of 68.17 h at dose of 1 × 108 spores/ml. ICAR-NBAIR Ma-35 showed LC50 value of 2.09 × 103 spores/ml and LT50 of 87.10 h at dose of 1 × 108 spores/ml. The use of isolate ICAR-NBAIR Ma-4 as a potential control agent of Poekilocerus pictus with a lower LC50 which killed faster half of Poekilocerus pictus individuals. This isolate can be further tested against the devastating invasive desert locust, Schistocerca gregaria for its management on the eggs and early hopper stages. [ABSTRACT FROM AUTHOR]

The Crop protection system is dominated by the use of synthetic insecticides however incorporation of fungal biocontrol agents (FBA) at lower doses is considered to consolidate the integrated pest management (IPM) program. The success of IPM is delimited and relies on the understanding of how its performance is affected by adverse effects on FBA by agrochemicals deployed for its management as well as of other pests and diseases. In this study, laboratory grade actives of three different insecticides used for the control of Tetranychus urticae were tested at different concentrations to determine their effects on germination, mycelial growth and sporulation of eight entomopathogenic fungal isolates under in vitro conditions. The fungal isolate with the most adverse effects on the biological index was further studied for underlying reasons of antagonism. This paper reports for the first time changes in conidial surface morphology, its germination and penetration capacity on mite cuticle, post insecticide treatment. Bioassays showed that all insecticide actives at their lowest concentration (12.5% MC) were most toxic to Beauveria bassiana P isolate. Ethion and chlorpyriphos were compatible with Hirsutella thompsonii PDBC-1 at 12.5% MC while propargite showed compatibility with B. bassiana MTCC 6097, Metarhizium anisopliae MTCC 4104 and Cordyceps fumosorosea MTCC 4636 at the same concentration. Further, SEM studies showed that post-insecticide treatments, there were structural deformations on the conidial surface with a decrease in its germination and germ tube penetration capacity on the cuticle of T. urticae. Future studies in this area will help in improving IPM along with overcoming insecticide resistance problems. [ABSTRACT FROM AUTHOR]

Whitefly, Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), has become a key pest of transgenic cotton crop in Pakistan. As insecticides are losing effectiveness, there is dire need to work on microbial and bioinsecticides for early season management of whitefly. The current study was designed for the evaluation of Beauveria bassiana and Metarhizium anisopliae and synthetic insecticides against whitefly to find out their effectiveness under laboratory and field conditions. Under laboratory conditions, significantly higher mortality (74-84%) was observed in treatments of synthetic insecticides (spirotetramat, flonicamid, pyriproxyfen and buprofezin) and bioinsecticides (Beauveria bassiana and Metarhizium anisopliae) against laboratory reared whitefly populations. However, when applied against whitefly at three locations under field conditions, these products (insecticides and entomopathogenic fungi) reduced the population ranging from 14-63% for nymphs and 16-62% for adults of whitefly. Synthetic insecticides, insect growth regulators (spirotetramat and pyriproxyfen) were found effective as nymphicidal action, whereas flonicamid and diafenthiuron were better as adulticidal action. Bioinsecticides showed the least effectiveness under the field conditions. This study is the first report of field evaluation from Pakistan and would help in application of entomopathogenic fungi as alternative technique for pest management in future. [ABSTRACT FROM AUTHOR]

In the Neotropics, leaf-cutting ants are pests of great importance to various crops. The natural defenses and complexity of these ants reduce the impact of potentially useful pathogens for biological control. Furthermore, several types of research with entomopathogenic fungi usually focus on only a few isolates of well-known species, like Beauveria bassiana and Metarhizium anisopliae, in addition to not always use isolates obtained from leaf-cutting ants. Here, we evaluated the pathogenicity of several filamentous fungi to workers of the leaf-cutting ant Atta sexdens rubropilosa. For that, we used fungi previously isolated in an extensive isolation study in Atta spp. reproductive females. Conidia suspensions of Aspergillus flavus, B. bassiana, Isaria fumosorosea and Purpureocillium lilacinum were prepared to a final concentration of 108 conidia mL− 1. In addition, we included sterilized distilled water as control and commercial B. bassiana as standard. Ant workers were immersed in these treatments for eight seconds. The number of dead workers was counted daily. Several fungal isolates killed more, or faster than the standard B. bassiana, showing that they may have a better potential for use in leaf-cutting ants´ biological control. Additionally, the present study reports for the first time the pathogenicity of P. lilacinum and I. fumosorosea towards Atta workers. Thus, we showed that an extensive and specific prospection is of importance for the development of biopesticides for leaf-cutting ants control. [ABSTRACT FROM AUTHOR]

Microcerotermes diversus Silvestri (Blattodea: Termitidae) is a worldwide destructive termite whose control by conventional methods is often difficult. Biological control using entomopathogenic fungi could be an alternative management strategy. Two species of entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana, isolated from natural habitats of Mashhad and Lahijan regions, Iran. The fungi were characterized based on sequences of ITS gene as well as classic data. Then, the infectivity of both isolates of M. anisopliae and B. bassiana in different concentrations (1 × 104, 1 × 105, 1 × 106, 1 × 107, and 1 × 108 conidia/ml) were evaluated under laboratory conditions by two methods, including spray and pipetting against termite, M. diversus. Both entomopathogenic fungi species were capable of infecting and killing M. divesrus. In the pipetting method, the LC50 value for B. bassiana and M. anisopliae calculated 8.03 × 105 (conidia/ml) and 1.03 × 106 (conidia/ml), respectively. But in the spray method, the effect of M. anisopliae on M. diversus was more than B. bassiana. The LC50 value in the spray method for B. bassiana and M. anisopliae was 3.52 × 107 (conidia/ml) and 1.65 × 106 (conidia/ml). The mortality caused by the fungus was dose-dependent, with the highest mortality recorded at the highest concentration. In the pipetting method, the mortality rate for B. bassiana and M. anisopliae was 0 to 97.5% and 0 to 100% at 8 day post infection. In the spray method, the mortality percentage for B. bassiana was from 2.5 to 72.5% and for M. anisopliae was 0 to100% by 4 days post-infection. The results of this study indicated that B. bassiana and M. anisopliae are potentially useful biological control agents for M. diversus. Future studies with field trails will provide a confident approach toward termite management. [ABSTRACT FROM AUTHOR]

Chemical control of Bactrocera cucurbitae in crops biomagnifies toxic residues in fruits and vegetables imposes health-hazard effects on consumers and demands for eco-friendly approaches. Present research assessed the bio-efficacy of Beauveria bassiana, Metarhizium anisopliae, Verticillium lecanii and Bacillus thuringiensis by adult-diet-bioassay at eleven concentrations (1 × 108, 5 × 107, 1 × 107, 5 × 106, 1 × 106, 5 × 105, 1 × 105, 5 × 104, 1 × 104, 5 × 103 and 1 × 103 CFU ml−1) of each entomopathogen against B. cucurbitae at three post-exposure-intervals (PEI) under controlled conditions. The results revealed that the maximum concentration (1 × 108 CFU ml−1) of B. bassiana, M. anisopliae, V. lecanii and B. thuringiensis caused 5.3 to 7.7, 7.4 to 9.2, 5.3 to 6.7 and 5.1 to 11.2 times higher mortality in B. cucurbitae, respectively at 10 d PEI as compared to mortality demonstrated by the same concentration at 3 d PEI. All tested microbial-insecticides induced statistically similar mortality in both male and female B. cucurbitae at each concentration for the same PEI. Correlation coefficient (r) values reveal that concentrations of each microbial-insecticide had a high positive correlation with mortalities of male and female B. cucurbitae [r(B. bassiana) = 0.691 to 0.865, r(M. anisopliae) = 0.643 to 0.849, r(V. lecanii) = 0.508 to 0.886 and r(B. thuringiensis) = 0.591 to 0.812]. Regression-parameters reveal that concentrations of tested microbial-insecticides had significant linear-relationship with and explained significant variability in B. cucurbitae mortality (P < 0.05). At maximum PEI (10 d), B. bassiana exhibited least LC50 (4.10 × 101 to 1.87 × 102 CFU ml−1) and proved highly toxic followed by M. anisopliae (1.16 × 102 to 3.55 × 102 CFU ml−1), B. thuringiensis (2.97 × 102 to 5.92 × 102 CFU ml−1) and V. lecanii (4.50 × 102 to 7.64 × 102 CFU ml−1). In conclusion, B. bassiana incorporated adult-diet proved highly effective against B. cucurbitae followed by M. anisopliae, B. thuringiensis and V. lecanii. Hence, B. bassiana can be recommended for incorporation in bait-traps to develop attract-and-kill technology for B. cucurbitae. [ABSTRACT FROM AUTHOR]

Panonychus citri (citrus red mite) is a devastating pest of citrus orchards. The conventional chemical acaricides have been strongly forbidden for the management of agricultural insect pests in China. Therefore, we evaluated the susceptibility of adult and nymphs P. citri in laboratory against eight isolates of four fungal species, Akanthomyces lecanii, Metarhizium anisopliae, Beauveria bassiana and Aschersonia aleyrodis. Each citrus seedling having 40 adults (2-d-old) and nymphs (on separate plants) were sprayed with isolates at the concentration of 104 ~ 108 conidia mLˉ1 whereas controlled seedlings were sprayed with 0.02% Tween-80. After 9 days of fungal exposure, the four fungal isolates caused more than 50% mortality of mites, such as; 85.6%, 87.9%, 64.6% and 79.7% by A. lecanii (V3450), B. bassiana (BFZ0409), M. anisopliae (MFZ0706) and A. aleyrodis (AsG0910), respectively. The nymphal mites were less susceptible to applied fungi compared to adults. The LC50s of the tested isolates were determined by the fitted time-concentration-mortality relationships, which declined over days after spray. LT50s were decreased with a high concentration of isolates. After the 9-d inoculation, two isolates of B. bassiana (BFZ0409 and D1344) and one isolate of A. lecanii (V3450) were highly effective at the minimal dose of LC50 of 104 conidia mLˉ1 and are promising candidates to control mites, as compared to other tested fungal isolates. [ABSTRACT FROM AUTHOR]

Sugarcane is one of the important commercial crop in India and white grubs are one of the serious pests of this crop. The present study was taken up to study the efficacy of entomopathogenic fungi against Holotrichia serrata(Fabricius) in sugarcane. Laboratory bioassay studies were conducted using five strains of Metarhizium anisopliae (ICAR-NBAIR Ma-4, Ma-6, Ma-11, Ma-14a & Ma-35) and one strain of Beauveria bassiana (ICAR-NBAIR Bb-5a) on third instar grubs of H. serrata at the concentration of 1 × 108 spores/ml. M. anisopliae (ICAR-NBAIR Ma-4) strain showed 100% mortality of the grubs and the rest of the strains showed 56–80% mortality of H. serrata. Dose and time mortality studies with aqueous spore suspensions and talc formulation (2% WP) of M. anisopliae (ICAR-NBAIR Ma-4 strain) showed LC50 value of 6.67 × 104 spores/ml and 1.72 g/l andLT50 value of 122.02 h at spore dose of 1 × 108 spores/ml and 183.86 h at the dose of 5 g/l. Further field evaluation was conducted in white grub infested sugarcane during 2016–17 and 2017–18 using M. anisopliae (ICAR-NBAIR Ma-4 strain) and B. bassiana (ICAR-NBAIR Bb-5a) for management of white grubs, H. serrata in Karnataka state of India. The results showed soil applications of 250 kg of M. anisopliae, (ICAR-NBAIR Ma-4) enriched Farmyard manure per hectare two times (June & July) effectively reduced the grub population of H. serrata by 86–89% leading to reduced plant damage and increased yield (33–34%). This treatment was better than the insecticidal application in the management of sugarcane white grubs. [ABSTRACT FROM AUTHOR]

The African citrus triozid Trioza erytreae Del Guercio (Hemiptera: Triozidae) is the most destructive citrus pest. Presently, biological data on T. erytreae are insufficient for important parameters like distribution, seasonal dynamics and entomopathogens. Therefore, we determined the temporal dynamics of T. erytreae along three different altitudinal gradients in Kenya. In low altitudes, females of T. erytreae reactivated and started laying eggs between late February and early March. The mean monthly number of immature stages of T. erytreae per flush shoot peaked in February, whereas adults peaked in March. For mid-altitudes, T. erytreae mean populations peaked in February, but adults were already present in December. In high altitudes, adults appeared in June, and females began laying eggs. Trioza erytreae population densities in shaded trees positively and significantly correlated with unshaded trees. There was a significant difference between adult density and maximum temperature, average temperature, solar radiation, evaporation and dew point. Furthermore, this study evaluated the effects of 11 Metarhizium anisopliae and 4 Beauveria bassiana fungal isolates against adult T. erytreae under laboratory conditions. Metarhizium anisopliae ICIPE 18 and ICIPE 69 were the most potent isolates, causing 97.5% and 82.5% mortalities within the shortest LT50 time of 4.4 and 5.9 days, respectively. The presence of Diaphorina citri Kuwayama (Hemiptera: Liviidae) on Zanthozylum capense requires further investigation. Our findings provide relevant information for early detection, monitoring and developing biopesticides against the pest. [ABSTRACT FROM AUTHOR]

Haplaxius crudus (Van Duzee) is the vector of the pathogen that causes Lethal wilt disease, one of the most important diseases of oil palm in Colombia. Currently, H. crudus populations are controlled with calendar applications of chemical insecticides, however, their efficacy and effect on the ecosystem are unknown. The use of entomopathogenic fungi such as Metarhizium anisopliae may be an alternative to control this pest in the crop since this fungus has been isolated from adults of H. crudus found in oil palm plantations. Therefore, the objective of this study was to evaluate the efficacy of 10 native strains of M. anisopliae to control adults of H. crudus under laboratory and field conditions. The strain CPMa1309 was selected because it caused mortalities in H. crudus adults greater than 90% at a dose of 1 × 1012 conidia/ha, as well as for its capacity to grow rapidly and produce large numbers of conidia on an artificial medium (4.95 × 107 conidia/ml). These results show the possibility of incorporating the fungus M. anisopliae CPMa1309 in an integrated management program for the biological control of H. crudus but it is important to validate its effectiveness under different agro-ecological conditions, where oil palm grows in Colombia. [ABSTRACT FROM AUTHOR]

The pathogenicity of various local entomopathogenic fungal isolates from the kingdom of Saudi Arabia has been tested in the laboratory against the red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae). Fungi were coded, isolated, and purified. Beauveria bassiana (Balsamo-Crivelli) Vuillemin, coded as: BbSA-1 PDA-15 and Metarhizium anisopliae (Metsch.) Sorokin, coded as: MaSA-1 PDA-15, isolates demonstrated significant potential against R. ferrugineus larvae. A 1 × 1010 conidia/mL concentration of positive fungal isolates along with natural B. bassiana was used against different stages of R. ferrugineus. Rhynchophorus ferrugineus larvae were supplied with synthetic diets that contain preservatives and non-preservatives. The fungal isolates BbSA-1 PDA-15 and MaSA-1 PDA-15 affected the egg hatchability and caused significant larval mortality of red palm weevil. It was shown that MaSA-1 PDA-15 is one of the most pathogenic fungi against R. ferrugineus larvae followed by BbSA-1 PDA-15 and Natural B. bassiana isolates. Therefore, these local fungal isolates have the potential to be used against R. ferrugineus. Further development in the research could facilitate the farmers to save their valuable palm trees from the notorious pest. [ABSTRACT FROM AUTHOR]

The recent isolation of an atoxigenic strain of Aspergillus flavus (Link) (Eurotiales: Trichocomaceae), which was virulent to all stages of Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae) has generated interest to investigate virulence of the entomopathogenic fungus against other crop pests, and how it compares with established commercial biopesticides. In this study, we tested the pathogenicity and virulence of the atoxigenic A. flavus strain to Ootheca mutabilis (Sahlberg) (Coleoptera: Chrysomelidae) in the laboratory compared to the commercial Metarhizium anisopliae (Metschnikoff Sorokin) (Hypocreales: Clavicipitaceae; OD®, ICIPE 69). Serial dilutions of both entomopathogenic fungi (1 × 106–1 × 109 conidia/ml) were evaluated against adult O. mutabilis. Distilled water and cypermethrin 5% EC were included as controls. The treatments were replicated four times and the bioassay was repeated once. Both fungi at 1 × 109 conidia/ml killed 100% of tested O. mutabilis within seven days in the 1st and 2nd trials. The concentration of both fungi that killed 50% of O. mutabilis was the same in both trials (5.3 × 106 conidia/ml). The time taken by A. flavus and ICIPE 69 to kill 50% of O. mutabilis was not significantly different in the 1st trial (3.4 ± 0.1 days and 2.9 ± 0.4 days, respectively). However, ICIPE 69 took a significantly shorter time (2.1 ± 0.4 days) than A. flavus (3.6 ± 0.2 days) to kill 50% of O. mutabilis in the 2nd trial. We concluded that A. flavus is comparably as pathogenic and virulent (in terms of cumulative mortality and LC50) against O. mutabilis as ICIPE 69, and therefore both fungi may be viable biopesticides for commercialization against this pest. [ABSTRACT FROM AUTHOR]

Anastrepha ludens (Loew) (Diptera: Tephritidae) is an important pest of mango and citrus in Mexico. Here, we report the effect of the entomopathogenic fungus Metarhizium anisopliae (Metsch.) Sorokin strain MAAP1 on mortality and food consumption in A. ludens adults. Experiments were carried out under laboratory conditions at 26 ± 2 °C, 60 ± 5% RH and 12:12 photoperiod. To assess pathogenicity and sublethal effects, we sprayed flies with 1 × 109 conidia/ml and 1 × 106 conidia/ml solutions, respectively. Food consumption was measured by providing known amounts of food through capillary tubes to caged flies. We found that M. anisopliae was highly virulent to A. ludens , causing 92.3 ± 0.62% mortality at day 13 post-exposure. Interestingly, food consumption reduced by 17% in flies exposed to the fungus. These results support the implementation of M. anisopliae within current strategies used for the integrated pest management of A. ludens. [ABSTRACT FROM AUTHOR]

The sweet potato weevil (SPW), Cylas formicarius, is a serious pest of sweet potato in Australia and Papua New Guinea. Ten strains of Metarhizium sp. isolated from Australian soil samples were evaluated for their growth characteristics and screened for virulence to adult SPW under laboratory conditions. All isolates except QD62 (48.6%) had moderate to high germination (66–97%), and all took 2 to 4 days to sporulate at 25 °C. The optimal temperature for radial growth for the majority of isolates was 30 °C, and there was a significant interaction between isolate and temperature (P< 0.05). Isolate QS155 showed the fastest radial growth at 30 °C. The internal transcribed spacer sequences showed slight variations among the isolates; however, all isolates were shown to be Metarhizium anisopliae. Isolates varied greatly in their virulence. At 10 days after inoculation (DAI) by immersion in a suspension of 1 × 107conidia/ml, 9 of the 10 isolates were virulent, causing 80–100% mortality of adult SPW. Only two isolates (QS001-6 and QS155) caused more than 50% mortality at 5 DAI. In dose-mortality bioassays, isolate QS155 had the lowest 20-day LC50 and LC90 values; however, there were no statistically significant differences in mortality among the three most promising isolates tested (QD66, QS001-6 and QS155). These results show that M. anisopliae isolate QS155 has potential as a microbial control agent for SPW, and that further evaluation under glasshouse and field conditions is warranted. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify and develop entomopathogenic fungi as biopesticides for management of Maruca vitrata (Fabricius). Fourteen isolates of Metarhizium anisopliae (Metchnikoff) Sorokin and six of Beauveria bassiana (Bals.-Criv.) Vuill. were screened against first instar larvae of M. vitrata. The two most virulent isolates were selected and further tested for production in four liquid media. Different formulations of one isolate were evaluated against different developmental stages. Metarhizium anisopliae ICIPE 18 and ICIPE 69 caused highest larval mortality of 91 and 81%, with lethal time to 50% mortality (LT50) values of 1.8 and 1.7 days and LC50 of 1.07 × 107 and 3.01 × 106conidia/ml, respectively. ICIPE 69 yielded more biomass and propagules in two liquid media than ICIPE 18. All developmental stages and adult moths were susceptible to fungal infection and horizontal transmission caused a significant reduction in fecundity. Isolate ICIPE 69 was identified as the most potent isolate for managing M. vitrata based on demonstrated efficacy against different developmental stages and amenability to production in liquid media and could be utilized as an alternative to pesticides in cowpea IPM. [ABSTRACT FROM AUTHOR]

In the present study, the susceptibility of different developmental stages (eggs, larvae, protonymphs, deutonymphs and adults) of Tetranychus urticae Koch to the entomopathogenic fungi Beauveria bassiana (Balsamo-Crivelli) Vuillemin and Metarhizium anisopliae (Metchnikoff) Sorokin was evaluated in the laboratory. At each developmental stage, four concentrations (3 × 105, 1 × 106, 3 × 106 and 1 × 107 conidia/ml) of both fungi were sprayed. Egg viability and motile-stage mortality varied among the fungal isolates and conidial concentrations. The highest conidial concentration (1 × 107 conidia/ml) significantly reduced the viability of eggs and increased the mortality of motile stages. However, deutonymphs and adults were more susceptible to fungal infection than larvae and protonymphs. The lethal concentration values to 50% (LC50) and 90% mortality (LC90) varied with the fungal isolates and developmental stages. The results show the prospects of B. bassiana and M. anisopliae for the control of T. urticae. [ABSTRACT FROM AUTHOR]

The Asian citrus psyllid Diaphorina citri Kuwayama is a destructive insect pest in citriculture, because it is an efficient vector of the proteobacteria ‘Candidatus Liberibacter asiaticus’ (Las), ‘Ca. L. africanus’ (Laf) and ‘Ca. L. americanus’ (Lam). These bacteria cause the ‘huanglongbing’ disease or ‘greening’ or ‘yellow dragon’ disease. The disease kills the plant and reduces fruit production. This insect pest is susceptible to entomopathogenic fungi, and we report the use of different strains of Metarhizium anisopliae, Cordyceps bassiana and Isaria fumosorosea against the nymphs and adults of D. citri under field conditions. The fungi were applied four times using a concentration of 2 × 1013 conidia/ha with a time interval of 15 days between applications. The percentage of control of Cb 108, Ma 65, Ma 14 and Ifr 4 was 60, 50, 40 and 35% in nymphs, and 50, 50, 42 and 22% in adults, respectively. Metarhizium anisopliae, C. bassiana and I. fumosorosea applied on Persian lime groves are more effective in reducing higher density of nymphs than adults of D. citri. [ABSTRACT FROM PUBLISHER]

A cotton field was used to set up an arena trial for investigating the dose transfer of oil-based ultra-low-volume sprays of Metarhizium anisopliae (Metchnikoff) Sorokin to the cotton bollworm Helicoverpa armigera (Hübner). Two doses of conidia (75 and 50 g/ha, being 3.75 × 1012 and 2.5 × 1012 conidia/ha, respectively) formulated in 2 litres (70:30, kerosene–peanut oil) were applied using a Berthoud ‘Micro Ulva’ to three groups of larvae of cotton bollworms positioned in three rows downwind of a single spray line. Both the distribution of the droplets and the effect of direct contact with spray droplets were quantified. The mean number of droplets decreased from 416 ( ± 60) droplets per cm2 (line 1; 0.4 m) to 45 ( ± 36) droplets per cm2 (line 3; 5 m). To achieve 50% mortality, >10 and >13 days were necessary for 75 and 50 g/ha, respectively. From day 15, the difference in mortality rates was significant between the two treatments. At line 3 (5 m), at 12 days after application, the mortality rate reached 52% for 75 g/ha and 47% for 50 g/ha. The results are discussed in view of optimizing the application of the biopesticides. [ABSTRACT FROM PUBLISHER]