Dispersion of adeleid oocysts by vertebrates in Gran Canaria, Spain: report and literature review.

Within the family Adeleidae, Adelina spp. belong to a group of arthropod pathogens. These parasites have been reported to have a wide geographic distribution, however, there are no reports of these protists in the Canary Islands, Spain. One of the peculiarities of the life cycle of Adelina spp. is the participation of a predator, because fecundation and sporulation occur inside the body cavity, and so necessitate destruction of the definitive host. The involvement therefore of a 'dispersion host', which eats the definitive host and spreads the oocysts through its faeces, is critical for the maintenance of certain Adelina spp. On the island of Gran Canaria, adeleid oocysts have been found in stool samples from four animals, three California kingsnakes (Lampropeltis californiae), and one feral cat. These animals were part of a larger coprological study of vertebrate parasites (117 snakes, 298 cats), where pseudoparasitic elements were also recorded. L. californiae and feral cats are invasive species which are widespread across the island and this novel finding of Adelina spp. oocysts in their faeces suggests that they could also serve as potential sentinel species for arthropod parasites.

Using the SSU, ITS, and Ribosomal DNA Operon Arrangement to Characterize Two Microsporidia Infecting Bruce Spanworm, Operophtera bruceata (Lepidoptera: Geometridae).

Research pertaining to the two closely-related microsporidian genera Nosema and Vairimorpha is hindered by inconsistencies in species differentiation within and between the two clades. One proposal to better delimit these genera is to restructure the Nosema around a "True Nosema" clade, consisting of species that share a characteristic reversed ribosomal DNA operon arrangement and small subunit (SSU) ribosomal DNA sequences similar to that of the Nosema type species, N. bombycis. Using this framework, we assess two distinct microsporidia recovered from the forest insect Bruce spanworm (Operophtera bruceata) by sequencing their SSU and internal transcribed spacer regions. Phylogenetic analyses place one of our isolates within the proposed True Nosema clade close to N. furnacalis and place the other in the broader Nosema/Vairimorpha clade close to N. thomsoni. We found that 25% of Bruce spanworm cadavers collected over the four-year study period were infected with microsporidia, but no infections were detected in cadavers of the Bruce spanworm's invasive congener, the winter moth (O. brumata), collected over the same period. We comment on these findings as they relate to the population dynamics of the Bruce spanworm-winter moth system in this region, and more broadly, on the value of ribosomal DNA operon arrangement in Nosema systematics.

Dr. Alois Huger - Laying the foundations for an integrated insect pathology.

Dr. Rer. Nat. Alois M. Huger had a long and distinguished career at the Institut für biologische Schädlingsbekämpfung (Institute for Biological Pest Control) Darmstadt, Germany, where he became one of the world's leading insect pathologists. He applied his experience and understanding of insect tissues and specialist skills in microscopy to diagnosis and elucidation of the pathology of insect diseases. During his career he discovered the Oryctes nudivirus and Bacillus thuringiensis subsp. tenebrionis, and was a member of teams unravelling amber disease in scarab beetles and the role of bacteria in parthenogenesis of parasitoids. He researched and described the life cycles of microsporidian and rickettsial pathogens of insects and was the first to describe the ultrastructure of a microsporidian spore. Dr. Huger carried out diagnosis of diseased insects over a period of 55years and has left us with many publications and a database containing thousands of records for ongoing investigation. Working with multiple pathogens in different systems, Dr. Huger obtained an overview second to none in the complexities of insect/pathogen relationships and has been at the forefront of making these discoveries benefit humanity. He is a worthy recipient of the Founders' Lecture Honoree Award, the highest honour of the Society for Invertebrate Pathology.

Are Entomopathogenic Nematodes Effective Biological Control Agents Against the Carob Moth, Ectomyelois ceratoniae?

The carob moth (Ectomyelois ceratoniae) is the key pest of pomegranate, which causes a significant percentage of losses in pomegranate orchards and warehouses of Iran annually. The pest larvae are characterized by displaying a cryptic behavior within the fruit, which avoids most routine control techniques, especially chemical method. The low efficiency of traditional measurements and also the rich species diversity of natural enemies within the infested fruits highlight the necessity of exploring effective control methods, especially environmental friendly approaches. Entomopathogenic nematodes (EPNs) are a group of biological control agents that actively search for the host, including those in a cryptic habitat like the carob moth larvae within infested fruits. Here, we assumed that treatment of the infested and dropped fruits with EPNs may provide new insight into the management of the carob moth. Three species of EPNs, Steinernema feltiae, S. carpocapsae, and Heterorhabditis bacteriophora were selected and used in a series of in vitro and in vivo experiments. In preliminary assays, the EPNs species were used with different concentrations of infective juveniles (IJs) (0, 1, 5, 10, 25, and 50 IJ/larvae) in 2-cm diam. plates. The mortality rates of the laboratory tests were 79.75% and 76.5% for S. feltiae and S. carpocapsae, corresponded to LC50 value of 2.02 IJ/larva for S. feltiae and 2.05 IJ/larva for S. carpocapsae. On the contrary, H. bacteriophora demonstrated low virulence on the pest larvae in petri tests with a LC50 = 426.92 IJ/larva. Hence, both Steinernema species were selected for subsequent experiments. The penetration rate for S. feltiae and S. carpocapsae into the hemocoel of the pest was 43% and 31%, respectively, and the corresponding reproduction rate was 15,452 IJ/larva for S. feltiae and 18,456 IJ/larva for S. carpocapsae. The gathered data from those in vitro tests were used for a field assay. Different concentrations (5, 10, 50, 100, and 160 IJ/cm2 of the arena) of S. feltiae and S. carpocapsae were applied in the field test. The mean mortality results from the last test were 10.89% and 26.65% for S. feltiae and S. carpocapsae, respectively. Finally, we found that these low virulence rates of the nematodes were attributed to inhibitory/repellency effects of saprophytic fungi within the infested pomegranates, a usual status of the infested fruits in autumn or winter seasons. Future work on additional EPN populations more adapted to the extreme conditions of the pomegranate production area in Iran may provide sufficient evidence to continue the further investigation on the best EPN species populations and advanced formulations with high durability.

Impacts of Nosema sp. (Microsporidia: Nosematidae) on the sugarcane borer, Diatraea saccharalis (Lepidoptera: Crambidae).

In Brazil, the sugarcane borer, Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae), is controlled with massive releases of the hymenopteran parasitoid Cotesia flavipes Cam. (Hymenoptera: Braconidae); over 3 million hectares of sugarcane are treated annually with 18 billion parasitoids. In order to meet this demand, parasitoids are produced in D. saccharalis under laboratory conditions where a Nosema sp. is reported to be an important problem in mass rearing of the host. The goals for this work were to study the pathogenicity of the Nosema sp. and the progression of the disease in the host under laboratory conditions. The average median lethal time (LT50) of Nosema sp. in first instar D. saccharalis varied from 9 ± 0.3 to 42 ± 2.3 days at concentration of 5 × 10(5)-0.5 spores/mm(3) artificial diet (10(7)-10 spores/µl). For third instar, the average of LT50 ranged from 32 ± 0.7 to 37 ± 0.7 days at concentration of 5 × 10(5)-5 × 10(2) spores/mm(3) artificial diet (10(7)-10(4) spores/µl in saline). The concentration necessary to cause 50% mortality (LC50) of first instar larvae was 5.6 (0.9-17.6) spores/µl and the estimated LC50 for third instar larvae was 1,200 (200-4700) spores/µl. The impacts of Nosema sp. on D. saccharalis were analyzed for first instar larvae fed 0.5 spores/mm(3) artificial diet. Duration and viability of the larval and pupal stages, adult longevity, pupal weight and fertility life table were measured for offspring of mating pairs composed of infected females and uninfected males or infected males and uninfected females and compared to offspring of uninfected pairs. Nosema sp. infection resulted in adverse effects on all biological parameters measured except for the duration of the larval and pupal stages and the weight of the male pupae, which did not differ statistically between infected and uninfected groups. The intrinsic rates of growth (rm) were greater for uninfected pairs compared to pairs with either male or female infected. The growth rate of individual larvae produced by uninfected adults was 48.2% faster than of larval offspring of infected females and it was negative (-0.003) when males were infected. Our study confirms the negative impact of the Nosema sp. in mass rearing of D. saccharalis for parasitoid production but shows potential for use as a microbial control agent of the sugarcane borer.

Pathogenicity of Two Species of Entomopathogenic Nematodes Against the Greenhouse Whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), in Laboratory and Greenhouse Experiments.

The greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) is a polyphagous pest in greenhouse crops. The efficacy of two entomopathogenic nematodes (EPN), Steinernema feltiae and Heterorhabditis bacteriophora, as biological control agents against T. vaporariorum was evaluated using two model crops typical of vegetable greenhouse productions: cucumber and pepper. Laboratory tests evaluated adults and second nymphal instars for pest susceptibility to different EPN species at different concentrations of infective juveniles (IJ; 0, 25, 50, 100, 150, 200, and 250 IJ per cm(2)); subsequent greenhouse trials against second nymphal instars on cucumber and pepper plants evaluated more natural conditions. Concentrations were applied in combination with Triton X-100 (0.1% v/v), an adjuvant for increasing nematode activity. In laboratory studies, both life stages were susceptible to infection by the two nematode species, but S. feltiae recorded a lower LC50 than H. bacteriophora for both insect stages. Similarly, in greenhouse experiments, S. feltiae required lower concentrations of IJ than H. bacteriophora to reach the same mortality in nymphs. In greenhouse trials, a significant difference was observed in the triple interaction among nematode species × concentration × plant. Furthermore, the highest mortality rate of the second nymphal instars of the T. vaporariorum was obtained from the application of S. feltiae concentrated to 250 IJ/cm(2) on cucumber (49 ± 1.23%). The general mortality caused by nematodes was significantly higher in cucumber than in pepper. These promising results support further investigation for the optimization of the best EPN species/concentration in combination with insecticides or adjuvants to reach a profitable control of this greenhouse pest.

Isolated and identified pathogenic bacteria from black soldier fly larvae with "soft rot" reared in mass production facilities and its incidence characteristics.

The black soldier fly larvae (BSFL) can transform organic waste into high-end proteins, lipids, chitin, biodiesel, and melanin at an industrial scale. But scaling up of its production capacity has also posed health risks to the insect itself. In this investigation, larval "soft rot" which is occurring in mass production facilities that cause larval developmental inhibition and a certain degree of death was reported. Responsible pathogen GX6 was isolated from BSFL with "soft rot" and identified to be Paenibacillus thiaminolyticus. No obvious impact on larval growth was observed when treated with GX6 spores, whereas mortality of 6-day-old BSFL increased up to 29.33% ± 2.05% when GX6 vegetative cells (1 × 106 cfu/g) were inoculated into the medium. Moreover, higher temperature further enhanced the BSFL mortality and suppressed larval development, but increasing substrate moisture showed the opposite effect. The middle intestine of infected larvae became swollen and transparent after dissection and examination. Transmission electron microscopy (TEM) observation indicated that GX6 had destroyed the peritrophic matrix and intestinal microvilli and damaged epithelial cells of larval gut. Furthermore, 16S rRNA gene sequencing analysis of intestinal samples revealed that gut microflora composition was significantly altered by GX6 infection as well. It can be noticed that Dysgonomonas, Morganella, Myroides, and Providencia bacteria became more numerous in the intestines of GX6-infected BSFL as compared to controls. This study will lay foundations for efficient control of "soft rot" and promote healthy development of the BSFL industry to contribute to organic waste management and circular economy.

Isolation of a Novel Alphabaculovirus (Baculoviridae) from Automeris liberia (Cramer, 1780) (Lepidoptera: Saturniidae) in African Oil Palms in Brazil.

A novel baculovirus observed to infect Automeris liberia (Cramer) (bullseye moth) is here described. Caterpillars of A. liberia with symptoms of viral infection were collected from African oil palm plantations in Tailândia, PA, Brazil. Macerated caterpillars were then offered to caterpillars of Automeris cinctistriga (Felder & Rogenhoper), leading to viral symptoms and death before pupation. A transmission electron microscope was used for virus ultrastructural identification. The presence of viral occlusion bodies (OBs) containing multiple nucleocapsids was observed and such features are compatible with Alphabaculovirus (Baculoviridae). Molecular detection by PCR with primers for polyhedrin gene (polh) and for late expression factor-8 gene (lef-8), confirmed that this isolate belonged to Alphabaculovirus genus. To our knowledge, this is the first record of a baculovirus isolated from or associated to Automeris. The name Automeris liberia nucleopolyhedrovirus (AuliNPV) is proposed for the new virus.

Exploration of RNA-Seq data to identify a potential pathogen of the leaf-mining moth, Stomphastis thraustica (Meyrick, 1908) (Lepidoptera: Gracillariidae).

The leaf-mining moth, Stomphastis thraustica (Meyrick, 1908) was imported to Australia as a potential biological control agent of an exotic weed, bellyache bush (Jatropha gossypiifolia), from Peru. The insect colony has been maintained in the quarantine facility for over eight years but recently, significant mortality was observed in the culture. The larvae demonstrated swollen intersegments with a fragile integument. The infected larvae are cloudy muted green or yellowish whereas a healthy late instar larva is a vivid green. They slowly dehydrate and eventually die, at which point the larval body becomes rubbery and turns to black. We used next generation sequencing to identify the cause of mortality in the insects. Total RNA was extracted from 20 larvae in two cohorts, one with and one without apparent symptoms of disease, for deep sequencing on NovaSeq platform after eukaryote ribosomal RNA depletion. We identified several non-insect sequences belonging to viruses, bacteria, and fungi, but none of those showed significant abundance or enrichment in the infected dataset. The sequences related to a unicellular yeast, Saccharomyces cerevisiae, and they were among the highly expressed non-insect contigs; more than 5% of reads in both libraries mapped to the genome of this opportunistic microorganism.

Mosquito Iridescent Virus: New Records from Nature and Infections Using Strelkovimermis spiculatus (Mermithidae) as a Vector Under Laboratory Conditions.

Iridoviridae is a DNA virus family that affects both vertebrates and invertebrates. Immature aquatic stages of many dipteran species infected with iridovirus have been found in different places worldwide. The most represented genera of the Culicidae family are Aedes and Psorophora. To date, sixteen species of Aedes naturally infected with iridoviruses have been reported. Moreover, there are four records for the genus Psorophora, one for Culiseta, and two for Culex. In this paper, we report two new mosquito species as natural hosts of iridoviridae in Argentina: Aedes albifasciatus (Macquart) and Culex dolosus (Lynch Arribalzaga). We also analyzed the ability of a Cx. pipiens-Invertebrate Iridescent Virus to replicate in vivo in the larval stage of two mosquito species, Culex apicinus Philippi and Ae. aegypti (L.) using Strelkovimermis spiculatus as a vector, under laboratory conditions. Although Ae. aegypti is the most recognized mosquito vector of important arboviruses responsible for emergent diseases, Cx. apicinus and Ae. albifasciatus may also be implicated in enzootic or epizootic cycles of virus transmission, such as the St. Louis Encephalitis virus and the Western Equine Encephalomyelitis virus.

Functional Characterization of Outer Membrane Proteins (OMPs) in Xenorhabdus nematophila and Photorhabdus luminescens through Insect Immune Defense Reactions.

Xenorhabdus nematophila and Photorhabdus luminescens are entomopathogenic bacterial symbionts that produce toxic proteins that can interfere with the immune system of insects. Herein, we show that outer membrane proteins (OMPs) could be involved as bacterial virulence factors. Purified totals OMPs of both bacterial species were injected into fifth instar larvae of Spodoptera exigua Hübner. Larvae were surveyed for cellular defenses fluctuations in total haemocyte counts (THC) and granulocyte percentage and for the humoral defenses protease, phospholipase A2 (PLA2), and phenoloxidase (PO) activities at specific time intervals. Changes in the expression of the three inducible antimicrobial peptides (AMPs), cecropin, attacin, and spodoptericin, were also measured. Larvae treated with OMPs of both bacterial species had more haemocytes than did the negative controls. OMPs of X. nematophila caused more haemocyte destruction than did the OMPs of P. luminescens. The OMPs of both bacterial species initially activated insect defensive enzymes post-injection, the degree of activation varying with enzyme type. The AMPs, attacin, cecropin, and spodoptericin were up-regulated by OMP injections compared with the normal larvae. The expression of these three AMPs was maximal at four hours post injection (hpi) with P. luminescens OMPs treatment. Expression of the three AMPs in X. nematophila treated insects was irregular and lower than in the P. luminescens OMPs treatment. These findings provide insights into the role of OMPs of entomopathogenic nematode bacterial symbionts in countering the physiological defenses of insects.

New Insight into the Management of the Tomato Leaf Miner, Tuta absoluta (Lepidoptera: Gelechiidae) with Entomopathogenic Nematodes.

The tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a serious threat to tomato production in the world. Due to serious issues with insecticide resistance, there is a dire need for alternative control methods. Entomopathogenic nematodes (EPN) have potential for the biological control of T. absoluta. In the laboratory, we examined the effect of temperature, soil type, and exposure time on the efficacy of the EPN species Steinernema carpocapsae (Nematoda: Steinernematidae) and Heterorhabditis bacteriophora (Nematoda: Heterorhabditidae) against last-instar T. absoluta larvae. Both species caused high mortality in loamy sand (89%) and coco peat (93%) but not in sandy loam (17%). H. bacteriophora caused 92-96% mortality at 19, 25, and 31°C; S. carpocapsae caused 89-91% mortality at 25 and 31°C but only 76% at 19°C. Both species caused similar mortality levels after 65-min exposure; thereafter, mortality increased only with S. carpocapsae reaching high levels even at a low concentration. Both species infected larvae within leaf galleries. When applied to whole large tomato plants in the greenhouse, both species provided similar control levels (48-51%) at high pest densities. Both species could be incorporated as an effective alternative to synthetic insecticides into T. absoluta management programs in greenhouse tomato production.

The role of pilin protein of Xenorhabdus nematophila against immune defense reactions of insects.

Xenorhabdus nematophila is a symbiotic bacterium of the entomopathogenic nematode Steinernema carpocapsae (Weiser). It produces several toxic proteins which interfere with the immune system of insects. The current study shows that purified pilin protein could be a virulence trait of X. nematophila. The fifth instar larvae of Spodoptera exigua (Hübner) was injected with purified pilin. Changes in the cellular defenses in terms of total haemocyte counts and granulocyte percentage and humoral factors including total protease, phospholipase A2, and phenoloxidase activities (humoral defense) as well as the expression of the three main antimicrobial peptides attacin, cecropin, and spodoptericin were measured at specific times. The level of THC and granulocytes in larvae with different concentrations of pilin protein were less than the negative control. Also agglutination of haemocytes was observed 8-16h post-injection. The pilin protein activated phenoloxidase in the initial hour post-injection, by 2hpi, activity was stable. The activities of phospholipase A2 and protease activities reached maximum levels at 12 and 4hpi, respectively, and then decreased. The expressions of attacin, cecropin, and spodoptericin in larvae treated with pilin protein were up-regulated above that of the normal sample. The overexpression of cecropin was greater than the other antimicrobial protein mRNA transcripts. The spodoptericin expression had an irregular trend while expressions of attacin and cecropin reached maximum levels at 4hpi and then decreased. Generally, after the injection of pilin protein, the cellular and humoral immune system of S. exigua is activated but this toxin was able to inhibit them. This is the first report of the role of pilin protein when the bacterial symbiont of S. carpocapsae encounters the humoral defense of an insect.

Molecular Genetics of Beauveria bassiana Infection of Insects.

Research on the insect pathogenic filamentous fungus, Beauveria bassiana has witnessed significant growth in recent years from mainly physiological studies related to its insect biological control potential, to addressing fundamental questions regarding the underlying molecular mechanisms of fungal development and virulence. This has been in part due to a confluence of robust genetic tools and genomic resources for the fungus, and recognition of expanded ecological interactions with which the fungus engages. Beauveria bassiana is a broad host range insect pathogen that has the ability to form intimate symbiotic relationships with plants. Indeed, there is an increasing realization that the latter may be the predominant environmental interaction in which the fungus participates, and that insect parasitism may be an opportunist lifestyle evolved due to the carbon- and nitrogen-rich resources present in insect bodies. Here, we will review progress on the molecular genetics of B. bassiana, which has largely been directed toward identifying genetic pathways involved in stress response and virulence assumed to have practical applications in improving the insect control potential of the fungus. Important strides have also been made in understanding aspects of B. bassiana development. Finally, although increasingly apparent in a number of studies, there is a need for progressing beyond phenotypic mutant characterization to sufficiently investigate the molecular mechanisms underlying B. bassiana's unique and diverse lifestyles as saprophyte, insect pathogen, and plant mutualist.

A study on Maruca vitrata infestation of Yard-long beans (Vigna unguiculata subspecies sesquipedalis).

Globally, Maruca vitrata (Geyer) is a serious yield constraint on food legumes including Yard-long bean (Vigna unguiculata subspecies sesquipedalis). However, there is a dearth of information on its damage potential, distribution and population dynamics in Yard-long beans. In the present study, the level of M. vitrata larval infestation on flowers and pods of Yard-long beans in Sri Lanka was determined with respect to three consecutive cropping seasons, Yala, Off and Maha. Results indicated that larval infestation and abundance varied with developmental stage of flowers and pods, cropping season and their combined interactive effects. Flowers of Yard-long beans were more prone to M. vitrata larval attack compared to pods. Abundance and level of infestation of M. vitrata varied with plant parts, having a ranking of flower buds (highest) > open flowers > mature pods > immature pods (lowest). Peak infestation was observed six and eight weeks after planting on flowers and pods, respectively. Among the three cropping seasons, M. vitrata infestation was found to be higher during Maha and Off seasons compared to Yala. The findings of this study contribute to the identified knowledge gap regarding the field biology of an acknowledged important pest, M. vitrata, in a previously understudied crop in Sri Lanka.

Host plant species can influence the fitness of herbivore pathogens: the winter moth and its nucleopolyhedrovirus.

Plants can have a significant impact on the fitness and efficacy of natural enemies. These interactions are widespread and suggest that the influences on the population dynamics of insect herbivores cannot be simply divided into "bottom up" and "top down". Several questions remain little studied in this field. Firstly, to what extent can plants affect the interactions between insects and their pathogens? Secondly, what are the effects of variation within natural enemy species on host/enemy/plant interactions? Finally, if plant/pathogen interactions can occur, do pathogens have increased fitness on the locally abundant food plant of their host? This study explored the influence of three host plant species of the polyphagous winter moth, Operophtera brumata, on infections caused by two geographic isolates of the winter moth nucleopolyhedrovirus (NPV) collected from distinct winter moth habitats. Insects were infected on excised leaf tissue of common oak, Quercus robur, Sitka spruce, Picea sitchenis, and heather, Calluna vulgaris. Parameters fundamental to the basic reproductive rate of the pathogen were estimated: these being infectivity, speed of kill and the yield of virus per insect. Leaf nitrogen and phenolic content were measured as indicators of host plant quality for the three plant species: oak had the highest levels of nitrogen and also the highest levels of phenolic compounds. Heather had higher levels of phenolic compounds than Sitka spruce. Host plant did not affect the infectivity of either isolate but insects that ingested virus on oak foliage died sooner and yielded more virus than insects that ingested virus on Sitka spruce or heather. The effect of host plant species on pathogen yield varied between the two isolates of the NPV but not as predicted by our adaptive hypothesis. The interactions between virus and food plant are discussed in relation to host and pathogen population dynamics.

Seleção de isolados de Beauveria bassiana para o controle de adultos do bicudo-do-algodoeiro Anthonomus grandis (Coleoptera: Curculionidae) / Selection of Beauveria bassiana strains for the control of cotton boll weevil Anthonomus grandis (Coleoptera: Curculionidae) adults

O bicudo-do-algodoeiro, Anthonomus grandis, é considerado uma das principais pragas da cultura do algodão, demandando uma grande quantidade de inseticidas para o seu controle. O objetivo do presente trabalho foi avaliar isolados deBeauveria bassianapara o controle deA. grandis. Para tanto, foram testados nove isolados provenientes de diferentes hospedeiros na concentração de 1 x 108 conídios/mL, em condições de laboratório. Todos os isolados testados foram patogênicos ao bicudo-do-algodoeiro, causando entre 50 e 85% de mortalidade confirmada. Os tempos letais para matar 50% dos insetos (TL50) variaram entre 2,30 e 8,66 dias. O isolado IBCB 241 destacou-se como o mais virulento, apresentando a maior percentagem de mortalidade confirmada e o menor TL50, podendo assim ser considerado um promissor agente de controle biológico para o bicudodo-algodoeiro A.grandis.

The cotton boll weevil, Anthonomus grandis, is one of the most important pests of the cotton crop, requiring an elevated quantity of insecticides for its control.The objective of this work was to evaluate the effectiveness ofBeauveria bassianastrains for A. grandis control. In this assay, 9 strains from different hosts were tested in the concentration of 1 x 108 conidia/mL, under laboratory conditions. All strains evaluated were pathogenic to the cotton boll weevil, causing between 50 and 85% confirmed mortality. The lethal time to kill 50% of insects (LT50) ranged between 2.30 and 8.66 days. The IBCB 241 strain stood out as the most virulent, presenting the highest percentage of confirmed mortality and the shortest LT50, and can therefore be considered as a promising agent for the biological control of the cotton boll weevil A. grandis.