Mite fauna (Acari) associated with apple orchards (Malus domestica) and spontaneous vegetation as reservoir for predatory mites / Acarofauna (Acari) associada a pomares de maçã (Malus domestica) e vegetação espontânea como reservatório de ácaros predadores

Abstract The aim of this study was to recognize the mite fauna associated with apple orchards in southern Brazil and present a dichotomous key of the species sampled and those already reported in apple trees in southern Brazil. The studies were carried out in the 2020/2021 harvest in seven apple orchards of the Eva, Fuji and Gala cultivars located in the municipalities of Muitos Capões, Antônio Prado (Rio Grande do Sul state) and São Joaquim (Santa Catarina state). The orchards were divided into quadrants and sampling was carried out monthly. In each orchard, 40 plants were sampled, with three leaves of each plant collected in apical, median and basal regions of a median branch. In addition, monthly five species of spontaneous plants per orchard were sampled. A total of 8,425 mites were found, with the greatest abundance in Antônio Prado (50%), followed by Muitos Capões (35.5%) and São Joaquim (14.5%). The specimens found belong to 29 families, 64 genera and 99 species, in addition to mites of the order Oribatida. The greatest diversity was found in spontaneous vegetation (59 species), being 19 exclusives to apple trees and 21 species common to apple trees and spontaneous vegetation. Phytoseiidae was the family that presented the greatest richness, with 16 species, of which seven were common in apple trees and spontaneous plants. The most abundant species was Aculus schlechtendali Nalepa (Eriophyidae) (39.5%), followed by Panonychus ulmi (Koch) (Tetranychidae) (14.6%), Polyphagotarsonemus latus (Banks) (Tarsonemidae) (9.4%) and Neoseiulus californicus (McGregor) (Phytoseiidae) (7.4%). These results suggest that the mite fauna present in apple orchards in different landscapes and management are distinct, with a greater diversity of phytoseiid mites present in organic areas. Therefore, to maintain a greater diversity of predatory mites in these orchards, organic management seems to be the most appropriate. Furthermore, the high acarine diversity found in spontaneous vegetation demonstrates the importance of maintaining these plants in orchards that serve as refuges and reservoirs, favoring the permanence of natural enemies in these environments.

Resumo O objetivo deste estudo foi reconhecer a acarofauna associada a pomares de macieira no sul do Brasil e apresentar uma chave dicotômica das espécies amostradas e daquelas já relatadas em macieiras no sul do Brasil. Os estudos foram realizados na safra 2020/2021 em sete pomares de macieiras das cultivares Eva, Fuji e Gala localizados nos municípios de Muitos Capões, Antônio Prado (RS) e São Joaquim (SC). Os pomares foram divididos em quadrantes e a amostragem foi realizada mensalmente. Em cada pomar foram amostradas 40 plantas, sendo três folhas de cada planta coletadas nas regiões apical, mediana e basal de um ramo mediano. Além disso, mensalmente foram amostradas cinco espécies de vegetação espontânea por pomar. Foram encontrados 8.425 ácaros, com maior abundância em Antônio Prado (50%), seguido por Muitos Capões (35,5%) e São Joaquim (14,5%). Os exemplares encontrados pertencem a 29 famílias, 64 gêneros e 99 espécies, além de ácaros da ordem Oribatida. A maior abundância foi encontrada em vegetação espontânea (59 espécies), sendo 19 exclusivas de macieiras e 21 espécies comuns a macieiras e vegetação espontânea. Phytoseiidae foi a família que apresentou maior riqueza, com 16 espécies, das quais sete eram comuns em macieiras e vegetação espontânea. A espécie mais abundante foi Aculus schlechtendali Nalepa (Eriophyidae) (39,5%), seguida por Panonychus ulmi (Koch) (Tetranychidae) (14,6%), Polyphagotarsonemus latus (Banks) (Tarsonemidae) (9,4%) e Neoseiulus californicus (McGregor) (Phytoseiidae) (7,4%). Esses resultados sugerem que a acarofauna presente em pomares de macieira em diferentes paisagens e manejos são distintas, com maior diversidade de ácaros fitoseídeos presentes em áreas orgânicas. Portanto, para manter uma maior diversidade de ácaros predadores nesses pomares, o manejo orgânico parece ser o mais adequado. Além disso, a elevada diversidade de ácaros encontrada na vegetação espontânea demonstra a importância da manutenção destas plantas em pomares que servem como refúgios e reservatórios, favorecendo a permanência de inimigos naturais nestes ambientes.

Mite fauna on apples in southern Brazil - Review and perspectives.

Brazil is among the largest apple producers in the world (Malus domestica Bork, Rosaceae), with production concentrated mainly in the southern of the country. Panonychus ulmi (Koch) (Tetranychidae) have economic importance in apple and, recently, Aculus schlechtendali (Nalepa) (Eriophyidae), was reported in Brazil. This review aims to delineate the distribution of the acarofauna associated to apple, with emphasis on the main groups of economic importance and their potential natural enemies and highlight the problems related to phytophagous species and management possibilities. Searches were carried out in databases, and the principal keywords were Aculus schlechtendali, Malus domestica and Panonychus ulmi. After the exclusion criteria resulted 166 publications. The social and economic importance of the apple has been increasing on the world, however, due to environmental imbalance, phytophagous mites are increasing their populations and acquiring resistance against acaricides. Panonychus ulmi has been reported in America for decades, being of economic importance for Brazil and the record of A. schlechtendali alerts to the possibility of damage in orchards in the country. Therefore, it is important that the literature be evaluated, that the mite species are identified and that forms of conscious management are developed. Prioritizing the human and animal health and environmental balance.

Acarofauna associated with organic matter in laying aviaries of different rearing systems in Brazil.

Due to the high density of chickens housed within the same space in aviaries, a large volume of organic matter accumulates on the floor. This large supply of available resources allows the development of arthropods, including organisms that affect poultry productivity and health. This study aimed to evaluate the composition of the mite community associated with organic matter in poultry houses with different rearing systems and the verification of potential predators to be evaluated in clean management techniques, such as biological control. The study was carried out in the state of Rio Grande do Sul (Brazil) in a total of six poultry houses, two of the 'Californian' system (SIG) and four of the 'cage free' system (SIF). In total, 839,459 specimens were collected, of which 358,044 were collected from SIF and 481,415 specimens from SIG. Fifty-two species/morphospecies were found and we observed a grouping of aviaries from the same rearing model. Species of medical veterinary importance were found, such as Dermanyssus gallinae, Megninia ginglymura, Ornithonyssus sylviarum and Tyrophagus putrescentiae. The results demonstrate that the organic matter present in the aviaries harbors a high diversity of mites of medical-veterinary importance and predators, which are influenced by the rearing system.

Two new species of the genus Ologamasus (Ologamasidae) from apple orchards in southern Brazil.

This paper describes two new species of the genus Ologamasus (Acari: Ologamasidae), namely Ologamasus margaridae n. sp. and Ologamasus tuberculatus n. sp., based on females, males and nymphal stages collected in apple orchards (Malus domestica Borkh.) in southern Brazil. Ologamasus tuberculatus has a distinctive pair of large pores inserted on protuberances on the dorsal shield.

Influence of laying hen-systems and ecologic variables on mites of medical and veterinary importance.

The search for improvements in the poultry production chain and for increased egg productivity have grown significantly. However, intensive production with or by using of confinement systems negatively affect the welfare of animals and is favoring the appearance of harmful ectoparasites in production. Due to differences in the existing management systems, (e.g. Californian and cage-free systems) and given the importance of the poultry industry in the international market, the aim of the present study was: (1) to compare mite community between SIG (Intensive system - cage: Californian) and SIF (Intensive system - free: cage free); (2) egg-laying systems to analyze how the abundances of the ectoparasites Dermanyssus gallinae, Megninia ginlgymura, and Ornithonyssus sylviarum are affected by these egg-laying models; (3) to evaluate the association between the functional diversity found in traps, organic matter, and feathers in both systems; and finally, (4) to analyze how abiotic factors (e.g. humidity, temperature at sampling) affect mite community composition inside each model. A total of 860,571 mites were sampled, belonging to 59 taxa from six functional groups. Mite composition in the SIF system was different from the SIG system, while their variations in dispersion homogeneity were quite similar to each other. Although taxonomic composition is different between them, they are quite similar when clustered according to functional diversity. The variables 'humidity' and 'temperature' were not determining factors for the appearance of species. The species that most contributed for distinguishing the models were: M. ginlgymura, Dermatophagoides farinae, D. gallinae, Tyrophagus putrescentiae, O. sylviarum, Blattisocius keegani, Glycyphagus sp., Acotyledon sp., and Cheyletus malaccensis, respectively. Dermanyssus gallinae was strongly associated with the Californian model. Two taxa were highly correlated with cloaca, neck, dorsum, and inner wings; variations in relative air humidity also affected M. ginlgymura and O. sylviarum populations. Organic matter had a high abundance of predatory mites with potential for controlling mites of sanitary importance in the poultry chain.

Acarofauna present in organic strawberry fields and associated weed species in southern Brazil.

The presence of weeds in the margins of strawberry crops can enhance populations of predatory mites as a measure to support conservation biological control. The aims of this study were (i) to assess the composition of the acarofauna associated with strawberries and the accompanying herbaceous plants in an organic farming system, and (ii) to evaluate the possible relationships between phytophagous and predatory mites occurring in this system. Strawberry leaves and whole plants of weeds were sampled biweekly from August 2014 to February 2015 in Lapa (Paraná, Brazil). In total, 23 weed species belonging to 10 families were identified; 3768 mite individuals (from 15 families and 4 suborders) were recovered, 77% on strawberries and 23% on weeds. Abundance of predatory mites on weeds was greater than on strawberry cultivars. On strawberries, the most abundant family was Tetranychidae (84%) followed by Phytoseiidae (11.6%). In total, 16 predatory mite species from the Phytoseiidae family were identified, 13 of them occurring on strawberry leaflets. Typholodromalus aripo, Neoseiulus californicus and Typhlodromips mangleae were the most abundant mite species on strawberry leaves. On weeds, most individuals were predatory mites (59%), whereas phytophagous mites represented 17.2%. The most abundant family was Phytoseiidae (36.4%). On weeds, the phytoseiid mite T. aripo was the most abundant species, representing 34.7%. Besides being found on strawberry leaflets, T. aripo was associated with 15 weed species. Among the weeds, Bidens pilosa showed the highest values of the Shannon index (1.97), Margalef index (3.04), and Pielou's evenness index (0.95). This study emphasizes the importance of surrounding weeds as a shelter for beneficial mitefauna in strawberry fields, likely contributing to enhance conservation biological control.

Case report: Tyrophagus putrescentiae (Acari) attacking laying birds in conventional poultry houses.

Tyrophagus putrescentiae (Schrank) (Acaridae) is one of the most allergenic mite species worldwide, and it particularly infests household environments, animal feed factories, and food factories. It has been the aim of several studies recently in the healthcare area due to its allergenic potential. However, there had been no records of this species attacking laying birds until this report. This is the first record of adverse reactions in animals triggered by infestations of this species. Therefore, the present study aims at describing the damages and symptomatology of T. putrescentiae infestations on commercial laying hens. Alopecia and dermatitis were symptoms exacerbated by T. putrescentiae infestation starting at 40 weeks old. The presence of this species on hens, as observed in the present study, might be directly related to the accumulation of food and poultry litter on these birds, in their cages, or in the vicinities. Hence, the results might be related to their feeding behavior, which consists of continuous supply of animal feed in these management systems. The present study provides an unprecedented record that reveals the importance and potential for emergency pest status of T. putrescentiae in the poultry industry. Its infestations in poultry houses probably required constant sanitary care and monitoring are required in order to prevent outbreaks of this mite.