Impact of natural epizootics of the fungal pathogen Neozygites floridana (Zygomycetes: Entomophthorales) on population dynamics of Tetranychus evansi (Acari: Tetranychidae) in tomato and nightshade

The tomato red spider mite, Tetranychus evansi (Acari: Tetranychidae) was recently introduced in Africa and Europe, where there is an increasing interest in using natural enemies to control this pest on solanaceous crops. Two promising candidates for the control of T. evansi were identified in South America, the fungal pathogen, Neozygites floridana and the predatory mite Phytoseiulus longipes. In this study, population dynamics of T. evansi and its natural enemies together with the influence of environmental conditions on these organisms were evaluated during four crop cycles in the field and in a protected environment on nightshade and tomato plants with and without application of chemical pesticides. N. floridana was the only natural enemy found associated with T. evansi in the four crop cycles under protected environment but only in the last crop cycle in the field. In the treatments where the fungus appeared, reduction of mite populations was drastic. N. floridana appeared in tomato plants even when the population density of T. evansi was relatively low (less than 10 mites/3.14 cm(2) of leaf area) and even at this low population density, the fungus maintained infection rates greater than 50%. The application of pesticides directly affected the fungus by delaying epizootic initiation and contributing to lower infection rates than unsprayed treatments. Rainfalls did not have an apparent impact on mite populations. These results indicate that the pathogenic fungus, N. floridana can play a significant role in the population dynamics of T. evansi, especially under protected environment, and has the potential to control this pest in classical biological control programs. (C) 2009 Elsevier Inc. All rights reserved.

Modelling the potential distribution of the invasive tomato red spider mite, Tetranychus evansi (Acari: Tetranychidae)

Predicting the potential geographical distribution of a species is particularly important for pests with strong invasive abilities. Tetranychus evansi Baker & Pritchard, possibly native to South America, is a spider mite pest of solanaceous crops. This mite is considered an invasive species in Africa and Europe. A CLIMEX model was developed to predict its global distribution. The model results fitted the known records of T. evansi except for some records in dry locations. Dryness as well as excess moisture stresses play important roles in limiting the spread of the mite in the tropics. In North America and Eurasia its potential distribution appears to be essentially limited by cold stress. Detailed potential distribution maps are provided for T. evansi in the Mediterranean Basin and in Japan. These two regions correspond to climatic borders for the species. Mite establishment in these areas can be explained by their relatively mild winters. The Mediterranean region is also the main area where tomato is grown in open fields in Europe and where the pest represents a threat. According to the model, the whole Mediterranean region has the potential to be extensively colonized by the mite. Wide expansion of the mite to new areas in Africa is also predicted. Agricultural issues highlighted by the modelled distribution of the pest are discussed.

Biology of predator mite Euseius alatus DeLeon (Acari: Phytoseiidae) under different temperatures

Biology of predator mite Euseius alatus DeLeon (Acari: Phytoseiidae) under different temperatures. Euseius alatus DeLeon (Acari: Phytoseiidae) is one of the most common predators of tropical fruit trees in Brazil, feeding of pollen, mites and other small arthropods. This predator presents wide distribution, occurring from Rio Grande do Sul to Ceara. This work had as objective to evaluate the effect of temperature oil the development and reproduction of E. alatus, in addition to determining their thermal requirements. The study was accomplished at temperatures of 18, 21, 24, 27, 30 and 33 degrees C; relative humidity of 70 +/- 5%; and 12-h photophase. At these temperatures, the egg-adult period lasted 14.0; 8.1; 5.5; 4.9; 3.8 and 3.1 days, respectively. The egg, larva, protonymph and deutonymph stages and the egg-adult period presented thermal thresholds of 12.52; 13.85; 14.86; 14.86 and 13.31 degrees C,and thermal constants of 22.32; 14.23; 16.23; 17.3 and 70.16 degrees days. The values for the parameters of the fertility life table, analyzed ill conjunction With the values of the different variables of development at different temperatures, showed that the temperature of 30 degrees C is the Most suitable for development and reproduction of E. alatus in the laboratory. Therefore, is it apparent that the best temperature conditions for the development of L alatus are found in the warmer regions of Brazil, such as those observed in northeastern Brazil.

Predation potential and biology of Protogamasellopsis posnaniensis Wisniewski & Hirschmann (Acari: Rhodacaridae)

Rhodacaridae are cosmopolitan mites mentioned as predators, although nothing is known about their potential as biological control agents. One of the objectives of the work reported in this paper was to evaluate the potential of Protogamasellopsis posnaniensis (Acari: Rhodacaridae) as predator of representative species of insects of the families Sciaridae (Bradysia matogrossensis (Lane)) and Thripidae (Frankliniella occidentalis (Pergande)), of mites of the family Acaridae (Tyrophagus putrescentiae (Schrank) and Rhizoglyphus echinopus (Fumouze & Robin) and of nematodes of the family Rhabditidae (Protorhabditis sp.). Another objective was to determine the biological cycle of P. posnaniensis when fed the prey on which it performed best in the preceding predation test. The study was conducted in a laboratory where the experimental units were maintained at 25 +/- 1 degrees C, 97 +/- 3% RH and in the dark. Although the predator was able to kill all prey species considered in this study, the most favorable prey were T. putrescentiae, F. occidentalis and Protorhabditis sp. Survivorship of the predator in predation tests was always 98% or higher. Life table biological parameters when the predator was fed T. putrescentiae were: R(o) = 109.29; T = 19.06 days; lambda = 1.28 e r(m) = 0.32 female/female/day. Despite preying upon larvae of B. matogrossensis, eggs of the former can also be killed by the latter. The results indicated that A posnaniensis is a promising biological control agent, deserving additional studies on its possible use for the control of soil pests. (C) 2008 Elsevier Inc. All rights reserved.

Role of entomopathogenic fungi in the control of Tetranychus evansi and Tetranychus urticae (Acari: Tetranychidae), pests of horticultural crops

The spider mites Tetranychus urticae Koch and Tetranychus evansi Baker and Pritchard are important pests of horticultural crops. They are infected by entomopathogenic fungi naturally or experimentally. Fungal pathogens known to cause high infection in spider mite populations belong to the order Entomophthorales and include Neozygites spp. Studies are being carried out to develop some of these fungi as mycoacaricides, as standalone control measures in an inundative strategy to replace the synthetic acaricides currently in use or as a component of integrated mite management. Although emphasis has been put on inundative releases, entomopathogenic fungi can also be used in classical, conservation and augmentative biological control. Permanent establishment of an exotic agent in a new area of introduction may be possible in the case of spider mites. Conservation biological control can be achieved by identifying strategies to promote any natural enemies already present within crop ecosystems, based on a thorough understanding of their biology, ecology and behaviour. Further research should focus on development of efficient mass production systems, formulation, and delivery systems of fungal pathogens.

Phytoseiid mites of the tribe Typhlodromini (Acari: Phytoseiidae) from sub-Saharan Africa

This is the ninth publication in a series on the taxonomy of phytoseiid mites of sub-Saharan Africa. Sixty-five phytoseiid species of the tribe Typhlodromini Wainstein, all of which are in the genus Typhlodromus Scheuten are reported in this paper (62 in the subgenus Anthoseius DeLeon and 3 in the subgenus Typhlodromus Scheuten). They refer to all species of this tribe known to occur in sub-Saharan Africa. Fifteen new species are described and 41 species are redescribed. Most of the reported species were collected in various habitats in southern Africa and in cassava habitats in tropical Africa. A key is included for the separation of these species.

A new flat mite (Acari: Prostigmata: Tenuipalpidae) from date palm in the Sultanate of Oman

Tenuipalpus omani n. sp. (Acari: Tenuipalpidae) is described from the Sultanate of Oman, based on adults of both sexes collected on date palm, Phoenix dactylifera L. (Arecaceae). This new species is most similar to T. eriophyoides Baker, T. pareriophyoides Meyer & Gerson and T. yarensis Hasan, Bashir & Wakil, also collected from date palm.

A new species of Proctolaelaps Berlese (Acari : Ascidae) from northeastern Brazil

Proctolaelaps bulbosus n. sp. (Acari: Ascidae) is described from adult females and males of a laboratory colony derived from a collection from Cocos nucifera L. (Arecaceae) in northeastern Brazil. This species is distinguished from other Proctolaelaps species by the absence of the setae z3 and R3, knobbed seta Z5 and long spermatodactyl.

Rediscovery and redescription of Silvaseius Barretoae (Yoshida-Shaul and Chant) (Acari : Phytoseiidae)

New collection records of Silvaseius barretoae (Yoshida-Shaul and Chant) are reported and a redescription of females as well as the first description of male are provided based on specimens collected in Argentina and Brazil.

Two new species of Tetranychus Dufour (Acari : Tetranychidae) from Peru

Two new species of spider mites (Tetranychidae) found on Solanaceae in Peru are described: Tetranychus singularis n. sp. from Datura stramonium L. and T. amazonensis n. sp. from Solanum caricaefolium Rusby.

Distribution of Tetranychus evansi and its predator Phytoseiulus longipes (Acari : Tetranychidae, Phytoseiidae) in southern Brazil

Tetranychus evansi is an important pest of tomato in several countries. The predatory mite Phytoseiulus longipes has been found in association with it in Uruguaiana, State of Rio Grande do Sul, Brazil. The objective of this study was to evaluate the distribution of those two species in Uruguaiana region. Bi-weekly samples of plant parts were taken between January 28 and April 30, 2007 in Uruguaiana and five neighboring counties. Tetranychus evansi was found in all counties, but P. longipes was only found in Uruguaiana, mainly in the urban area. It is conceivable that such restricted distribution of P. longipes is due to its recent introduction to the region. Alternatively, unfavorable winter conditions could prevent its persistence, except in protected places. Buildings and vegetation characteristics of the urban area of Uruguaiana could moderate strong winds, intense rainfall and low temperatures that commonly occur in the area.

Biogeographic distribution of the phytoseiidae (Acari : Mesostigmata)

More than 1982 species in 90 genera were included in an analysis of the biogeography of the Phytoseiidae, a family of predatory mites. Seven biogeographic regions were taken into account: Nearctic, Neotropical, Ethiopian, West Palaearctic, East Palaearctic, Oriental, and Australasian. The number of species was particularly high in the Neotropical, Oriental, and West Palaearctic regions. These regions also present the highest levels of species endemism. The number of genera was quite similar in all regions except for the Neotropics, which also had a high level of endemism. The possible Gondwanian (Neotropical, Ethiopian, Australasian, and Oriental regions) origin of the Phytoseiidae, most probably in the Neotropics, and their possible radiation to Laurasia (Nearctic, West Palaearctic, and East Palaearctic regions) are discussed. The comparison between genera and species in the different biogeographic regions indicate the importance of both dispersal and vicariance events in the evolution of the group. Dispersal is assumed to have been most important between Neotropical and Nearctic regions and between East Palaearctic and Oriental regions, whereas vicariance could have been the dominating process between Australasian, Ethiopian, and Oriental regions, as well as between West and East Palaearctic regions. A parsimony analysis of endemicity showed the Neotropical and the Nearctic regions to be isolated from the other regions. This is certainly due to a diversification after the continents drifted apart and then a high dispersal between Nearctic and Neotropical regions. Different phylogenetic hypotheses and scenarios are proposed for each subfamily based on the results obtained and further investigations are proposed. (C) 2008 The Linnean Society of London.

Phytoseiid mites (Acari : Phytoseiidae) of the subfamilies Phytoseiinae Berlese and Typhlodrominae Wainstein from Peru, with descriptions of two new species

This paper reports the mites of the subfamilies Phytoseiinae and Typhlodrominae (Phytoseiidae) from Peru, providing descriptions of 2 new species, Phytoseius ortegae Guanilo and Moraes, n. sp. and Phytoseius poripherus Guanilo and Moraes, n. sp., and a taxonomic key to separate the species reported.

Effects of soybean proteinase inhibitors on development of the soil mite Scheloribates praeincisus (Acari : Oribatida)

Proteinase inhibitors (PI) are present in plant tissues, especially in seeds, and act as a defense mechanism against herbivores and pathogens. Serine PI from soybean such as Bowman-Birk (BBPI) and Kunitz have been used to enhance resistance of sugarcane varieties to the sugarcane borer Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae), the major pest of this crop. The use of these genetically-modified plants (GM) expressing PI requires knowledge of its sustainability and environmental safety, determining the stability of the introduced characteristic and its effects on non-target organisms. The objective of this study was to evaluate direct effects of ingestion of semi-purified and purified soybean PI and GM sugarcane plants on the soil-dwelling mite Scheloribates praeincisus (Berlese) (Acari: Oribatida). This mite is abundant in agricultural soils and participates in the process of organic matter decomposition; for this reason it will be exposed to PI by feeding on GM plant debris. Eggs of S. praeincisus were isolated and after larvae emerged, immatures were fed milled sugarcane leaves added to semi-purified or purified PI (Kunitz and BBPI) or immatures were fed GM sugarcane varieties expressing Kunitz and BBPI type PI or the untransformed near isogenic parental line variety as a control. Developmental time (larva-adult) and survival of S. praeincisus was evaluated. Neither Kunitz nor BBPI affected S. praeincisus survival. On the other hand, ingestion of semi-purified and purified Kunitz inhibitor diminished duration of S. praeincisus immature stages. Ingestion of GM senescent leaves did not have an effect on S. praeincisus immature developmental time and survival, compared to ingestion of leaves from the isogenic parental plants. These results indicate that cultivation of these transgenic sugarcane plants is safe for the non-target species S. praeincisus.

Exploration of the acarine fauna on coconut palm in Brazil with emphasis on Aceria guerreronis (Acari : Eriophyidae) and its natural enemies

Coconut is an important crop in tropical and subtropical regions. Among the mites that infest coconut palms, Aceria guerreronis Keifer is economically the most important. We conducted surveys throughout the coconut growing areas of Brazil. Samples were taken from attached coconuts, leaflets, fallen coconuts and inflorescences of coconut palms in 112 localities aiming to determine the Occurrence and the distribution of phytophagous mites, particularly A. guerreronis, and associated natural enemies. Aceria guerreronis was the most abundant phytophagous mite followed by Steneotarsonemus concavuscutum Lofego & Gondim Jr. and Steneotarsonemus furcatus De Leon (Tarsonemidae). Infestation by A. guerreronis was recorded in 87% of the visited localities. About 81% of all predatory mites belonged to the family Phytoseiidae, mainly represented by Neoseiulus paspalivorus De Leon, Neoseiulus baraki Athias-Henriot and Amblyseius largoensis Muma; 12% were Ascidae, mainly Proctolaelaps bickleyi Bram, Proctolaelaps sp nov and Lasioseius subterraneus Chant. Neoseiulus paspalivorus and N. baraki were the most abundant predators on attached coconuts. Ascidae were predominant on fallen coconuts, while A. largoensis was predominant on leaflets; no mites were found on branches of inflorescences. Leaflets harboured higher mite diversity than the attached coconuts. Mite diversity was the highest in the state Para and on palms surrounded by seasonal forests and Amazonian rain-forests. Neoseiulus paspalivorus, N. baraki and P. bickleyi were identified as the most promising predators of A. guerreronis. Analyses of the influence of climatic factors revealed that dry ambient conditions favour the establishment of A. guerreronis. Neoseiulus paspalivorus and N. baraki have differing climatic requirements; the former being more abundant in warm and dry areas, the latter prevailing ill moderately tempered and humid areas. We discuss the significance of our findings for natural and biological control of A. guerreronis.