Alaine Maria Lopes Catão

Bio: Alaine Maria Lopes Catão is an academic researcher from Universidade Federal de Goiás. The author has contributed to research in topics: Metarhizium anisopliae & Biological pest control. The author has an hindex of 3, co-authored 6 publications receiving 22 citations. Previous affiliations of Alaine Maria Lopes Catão include National University of La Plata.

Efficacy of Tolypocladium cylindrosporum against Aedes aegypti eggs, larvae and adults

Abstract: Aims The aim of this study was to test the activity of seven Tolypocladium cylindrosporum isolates against different developmental stages of Aedes aegypti. Methods and results Ovicidal activity (≤30% of eclosion; at a 84% eclosion of control eggs) and lowest cumulative emergence of adults (≤30%; at a 66·3% control emergence) originating from eclosing larvae was found 15 and 30 days, respectively, after applying conidia of ARSEF 962 or 1580 onto the eggs. All isolates induced larval mortality when third-instar larvae were treated with conidia (≤5% control mortality); the lowest lethal concentration (LC50) at 5 days after treatment was found with ARSEF 1580 (9·2 × 10(5) conidia ml(-1)), and the shortest lethal time (LT50 ) with ARSEF 2912 (2·8 days at 3·3 × 10(6) conidia ml(-1)). The pathogenicity of T. cylindrosporum to A. aegypti adults is corroborated. ARSEF 1027, 1580 and 2912 induced the highest cumulative mortality in adults (≥90%) 15 days after application (≤5% control mortality). Conclusions Findings emphasized an isolate- and developmental stage-related virulence of T. cylindrosporum. Significance and impact of the study ARSEF 1580, in the group of tested isolates, is the most promising isolate for use against terrestrial eggs, aquatic larvae and adults of this important vector.

Relative humidity impacts development and activity against Aedes aegypti adults by granular formulations of Metarhizium humberi microsclerotia.

Abstract: The impact of ambient relative humidity (RH) on conidial production of Metarhizium humberi IP 46 microsclerotia (MS) formulated in pellets or granules was investigated, and a promising granular formulation was tested against Aedes aegypti adults to confirm its efficacy. Microcrystalline cellulose (MC) and diatomaceous earth (DE) or a combination of vermiculite (VE), DE and silicon dioxide (SD) were tested as carriers in granular formulations containing MS. A range of 93-96.5% RH was critical for fungal development, and at least 96.5-98.5% RH was required for high conidial production on pellets or granules. Conidial production was clearly higher on pellets and granules prepared with VE than MC as the main carrier. VE granules containing MS were highly active against A. aegypti adults. Most mosquitoes were killed within 6 days after treatment regardless of the exposure time of adults to the formulation (1 min-24 h) or ambient humidity (75 or >98%). Production of conidia on dead adults varied between 7.3 × 106 and 2.2 × 107 conidia/individual, when exposed to MS granules for 12 h and 1 min, respectively. Granular formulations containing VE as the main carrier and MS as the active ingredient of M. humberi have strong potential for use against A. aegypti. KEY POINTS: • High conidial production on granular microsclerotial formulations at >96.5% RH • Vermiculite is more appropriate as a carrier than microcrystalline cellulose • Granules with IP 46 microsclerotia are highly active against Aedes aegypti adults.

Inorganic pellets containing microsclerotia of Metarhizium anisopliae: a new technological platform for the biological control of the cattle tick Rhipicephalus microplus

Abstract: This study was sought to devise pellets containing inorganic materials and microsclerotia of Metarhizium anisopliae strain IP 119 for biological control of Rhipicephalus microplus, the most economically important tick in Brazilian cattle industry. In addition, we evaluated the storage stability of the pellets, their tolerance to ultraviolet radiation (UV-B), and efficacy against ticks under laboratory conditions. Fungal microsclerotia were produced by liquid culture fermentation and mixed with pre-selected inorganic matrices: vermiculite powder, diatomaceous earth, and colloidal silicon dioxide (78:20:2, w/w/w). The microsclerotial pellets were then prepared by a two-stage process involving extrusion and spheronization. Pellet size averaged 525.53 ± 7.74 μm, with a sphericity index of 0.72 ± 0.01, while biomass constituents did not affect the wet mass properties. Conidial production from microsclerotial pellets upon rehydration ranged from 1.85 × 109 to 1.97 × 109 conidia g−1 with conidial viability ≥ 93%. Conidial production from pellets stored at 4 °C was invariable for up to 21 days. Unformulated microsclerotia and microsclerotial pellets were extremely tolerant to UV-B compared with aerial conidia. Engorged tick females exposed to conidia from sporulated pellets applied to soil samples and upon optimal rehydration exhibited shorter oviposition time length, shorter life span, and reduced number of hatched larvae. In summary, microsclerotial pellets of M. anisopliae IP 119 effectively suppressed R. microplus and showed outstanding UV-B tolerance in laboratory tests. Prospectively, this formulation prototype is promising for targeting the non-parasitic stage of this tick on outdoor pasture fields and may offer a novel mycoacaricide for its sustainable management. • Pellets with microsclerotia and inorganic materials are innovative for tick control. • Metarhizium microsclerotia show superior UV-B tolerance in relation to conidia. • Pellets of Metarhizium microsclerotia produce infective conidia against ticks.

composição e processo de preparação multiparticulada de natureza sólida contendo microescleródios de metarhizium anisopliae para controle de artrópodes-praga de importância na saúde humana, veterinária e na agropecuária e seus usos

Abstract: composicao e processo de preparacao multiparticulada de natureza solida contendo microesclerodios de metarhizium anisopliae para controle de artropodes-praga de importância na saude humana, veterinaria e na agropecuaria e seus usos. a presente invencao descreve formulacoes e processos de obtencao de sistemas solidos multiparticulados contendo microesclerodios de metarhizium anisopliae para o controle biologico de artropodes-praga, especialmente de rhipicephalus microplus (carrapato-do-boi). essa forma de apresentacao pode facilitar a aplicacao dos agentes biologicos no campo, tornando-a mais reprodutivel e efetiva, alem de mais segura. os fungos formulados se apresentam com viabilidade estavel sob refrigeracao e os bioensaios comprovam sua efetividade. dessa forma, as formulacoes descritas aqui devem possibilitar um controle biologico mais eficaz e mais seguro que as formulacoes existentes atualmente.

Entomopathogenic Fungi: New Insights into Host-Pathogen Interactions.

Abstract: Although many insects successfully live in dangerous environments exposed to diverse communities of microbes, they are often exploited and killed by specialist pathogens. Studies of host-pathogen interactions (HPI) provide valuable insights into the dynamics of the highly aggressive coevolutionary arms race between entomopathogenic fungi (EPF) and their arthropod hosts. The host defenses are designed to exclude the pathogen or mitigate the damage inflicted while the pathogen responds with immune evasion and utilization of host resources. EPF neutralize their immediate surroundings on the insect integument and benefit from the physiochemical properties of the cuticle and its compounds that exclude competing microbes. EPF also exhibit adaptations aimed at minimizing trauma that can be deleterious to both host and pathogen (eg, melanization of hemolymph), form narrow penetration pegs that alleviate host dehydration and produce blastospores that lack immunogenic sugars/enzymes but facilitate rapid assimilation of hemolymph nutrients. In response, insects deploy an extensive armory of hemocytes and macromolecules, such as lectins and phenoloxidase, that repel, immobilize, and kill EPF. New evidence suggests that immune bioactives work synergistically (eg, lysozyme with antimicrobial peptides) to combat infections. Some proteins, including transferrin and apolipophorin III, also demonstrate multifunctional properties, participating in metabolism, homeostasis, and pathogen recognition. This review discusses the molecular intricacies of these HPI, highlighting the interplay between immunity, stress management, and metabolism. Increased knowledge in this area could enhance the efficacy of EPF, ensuring their future in integrated pest management programs.

Characterization of Tolypocladium cylindrosporum (Hypocreales, Ophiocordycipitaceae) isolates from Brazil and their efficacy against Aedes aegypti (Diptera, Culicidae).

Abstract: AIMS To survey and to characterize entomopathogenic fungi as natural enemies of mosquitoes in Central Brazil. METHODS AND RESULTS Tolypocladium cylindrosporum (Hypocreales, Ophiocordycipitaceae) was isolated for the first time in South America by using Aedes aegypti (Diptera, Culicidae) as sentinel larvae in a stagnant mosquito breeding site in a secondary tropical forest. Two isolates were morphologically and molecularly identified, and their activity tested against A. aegypti eggs, larvae and adults. CONCLUSIONS Findings emphasize the importance of T. cylindrosporum as a natural fungal antagonist of mosquitoes. SIGNIFICANCE AND IMPACT OF THE STUDY Both isolates affected larvae and adults but were less effective against eggs; both have potential for development as a mycoinsecticide especially against larvae of A. aegypti the main vector of dengue, chikungunya, Zika and urban yellow fever.

Relative humidity impacts development and activity against Aedes aegypti adults by granular formulations of Metarhizium humberi microsclerotia.

Abstract: The impact of ambient relative humidity (RH) on conidial production of Metarhizium humberi IP 46 microsclerotia (MS) formulated in pellets or granules was investigated, and a promising granular formulation was tested against Aedes aegypti adults to confirm its efficacy. Microcrystalline cellulose (MC) and diatomaceous earth (DE) or a combination of vermiculite (VE), DE and silicon dioxide (SD) were tested as carriers in granular formulations containing MS. A range of 93-96.5% RH was critical for fungal development, and at least 96.5-98.5% RH was required for high conidial production on pellets or granules. Conidial production was clearly higher on pellets and granules prepared with VE than MC as the main carrier. VE granules containing MS were highly active against A. aegypti adults. Most mosquitoes were killed within 6 days after treatment regardless of the exposure time of adults to the formulation (1 min-24 h) or ambient humidity (75 or >98%). Production of conidia on dead adults varied between 7.3 × 106 and 2.2 × 107 conidia/individual, when exposed to MS granules for 12 h and 1 min, respectively. Granular formulations containing VE as the main carrier and MS as the active ingredient of M. humberi have strong potential for use against A. aegypti. KEY POINTS: • High conidial production on granular microsclerotial formulations at >96.5% RH • Vermiculite is more appropriate as a carrier than microcrystalline cellulose • Granules with IP 46 microsclerotia are highly active against Aedes aegypti adults.