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G.j. De Moraes - One of the best experts on this subject based on the ideXlab platform.

  • Mites (Acari) of cassava (Manihot esculenta Crantz) habitat in southern Africa
    'Informa UK Limited', 2018
    Co-Authors: Hanna R., G.j. De Moraes, Kreiter S., Phiri G., Jone A.
    Abstract:

    Consideration of possible side-effects of exotic biological control agents on their new environments is a necessary step in classical biological control programs. The evaluation of such effects usually requires the knowledge of the fauna present in those environments prior to introduction of control agents. This paper presents the first of a series of studies to evaluate the safety of a classical biological control program of the cassava green mite Mononychellus tanajoa (Bondar) in Mozambique and Malawi involving the introduction of Typhlodromalus aripo DeLeon, a predatory mite of the family Phytoseiidae. The objective of this study was to determine the mite fauna of cassava and of some of the visually most common plant species in or around cassava fields in those countries. The study was conducted at different occasions in the dry and rainy seasons, in 26 fields in Mozambique and 20 fields in Malawi representing a range of ecosystems. Twenty-one phytoseiid species were recorded in Mozambique and 32 in Malawi. On cassava, the dominant Phytoseiids were Euseius baetae (Meyer & Rodrigues), Euseius bwende (Pritchard & Baker) and Typhlodromalus saltus(Denmark & Muma) in Mozambique, and Euseius fustis (Pritchard & Baker), Iphiseius degenerans (Berlese) and T. saltus in Malawi. On other plants, the dominant Phytoseiids were Euseius baetae, Amblyseius sundi Pritchard & Baker and Parphytoseius horrifer (Pritchard & Baker) in Mozambique, and I. degenerans,Euseius magucii (Meyer & Rodrigues) and Euseius orygmus (Ueckermann & Loots) in Malawi. Several of the most common plants associated with cassava were observed to harbor phytoseiid species that were also found on the latter. Those plants may be important as reservoirs of such predators when conditions are not appropriate for them to live on cassava. This seemed to be particularly true for 6 Phytoseiids in Mozambique (A. sundi, E. magucii, P. horrifer, Typhlodromalus spinosus(Meyer & Rodrigues), Typhlodromips shi (Pritchar & Baker) and Neoseiulus teke (Pritchard & Baker)), and 6 Phytoseiids in Malawi (E. orygmus, Phytoseius amba Pritchard & Baker, T. shi, Typhlodromus (Anthoseius) kikuyuensis Swirski & Ragusa, Typhlodromus (Anthoseius) malawiensis Annou, Moraes & Hanna and N. teke), that were found on cassava at the end of the rainy season, but only on other plants in the dry season. M. tanajoa was the dominant mite species on cassava in both countries in addition to the Phytoseiids; few other species were found on that plant in either country. A larger diversity of mites in addition to Phytoseiids was found on other plants, but always at low numbers. Phytoseiids diversity and abundance varied between savannah and forest zones. These variations are likely due differences in biotic and abiotic factors between the two zones

  • Native phytoseiid mites as indicators of non-target eVects of the introduction of Typhlodromalus aripo for the biological control of cassava green mite in Africa
    'Elsevier BV', 2018
    Co-Authors: Zannou I.d., G.j. De Moraes, Hanna R., Kreiter S., Phiri G., Agboton B., Jone A.
    Abstract:

    Article purchasedThe need to evaluate non-target effects of classical biological control of arthropod pests has received considerable attention in recent years. We determined with repeated field surveys the changes in abundance and distribution of the phytoseiid mite fauna in cassava fields resulting from the introduction of the neotropical phytoseiid Typhlodromalus aripo into two countries—Malawi and Mozambique—in southern Africa for the biological control of Mononychellus tanajoa. Typhlodromalus aripo abundance was similar, while the abundance of the target pest M. tanajoa declined progressively, during the 2 years after the introduction of T. aripo into the target countries. We did not detect any changes in the abundance of the most common native Phytoseiids mites—Euseius baetae, Euseius bwende and Ueckermannseius saltus—on cassava in Mozambique. In contrast, the abundance of two of the most common native Phytoseiids, Euseius fustis and Iphiseius degenerans, on cassava in Malawi were apparently facilitated—i.e., their abundance was enhanced by the introduction of T. aripo; while the abundance of a third species, U. saltus, was not affected. For only one species, E. baetae, within-plant distribution shifted to the lower parts of the cassava canopy as a result of the introduction of T. aripo, which resides in the upper parts of the cassava canopy, but without any measurable negative effects on biological control of M. tanajoa. While the overall abundance of phytoseiid mites found on non-cassava vegetation was not affected by T. aripo introduction, there were some changes in relative abundance of some species in Malawi. Possible mechanism for the increase in abundance of I. degenerans and E. fustis in Malawi, and changes in within-plant distribution of E. baetae and I. degenerans in Mozambique and Malawi, respectively, are discussed. The methodology developed for assessing potential non-target effects of T. aripo introduction into southern Africa has significantly advanced classical biological control efforts against an economically important cassava pest

  • Phytoseiid mites of Colombia (Acarina: Phytoseiidae).
    International Journal of Acarology v. 8 n. 1 p. 15-22 1982., 2017
    Co-Authors: G.j. De Moraes, Denmark H. A., Guerrero J. M.
    Abstract:

    This is the second report of the Phytoseiids of Colombia. A new genus and species, Quadromalus colombiensis and Euseius ricinus n.sp. are described, bringing the total to 17 species of Phytoseiids for Colombia.bitstream/item/158807/1/1982-Moraes-Phytoseiid-649.PD

  • Plant inhabiting phytoseiid predators of midwestern Brazil, with emphasis on those associated with the tomato red spider mite, Tetranychus evansi (Acari: Phytoseiidae, Tetranychidae)
    Acarologia, 2014
    Co-Authors: I.p. Furtado, G.j. De Moraes, S. Kreiter, C.h.w. Flechtmann, M. Tixier, M. Knapp
    Abstract:

    The fauna of phytoseiid mites in the state of Mato Grosso do Sul, in midwestern Brazil, is poorly known. The tomato red spider mite, Tetranychus evansi Baker and Pritchard, is an important pest of Solanaceae in several countries, but it is usually found in low densities in Brazil. It has been hypothesized that this is due to the effect of natural enemies. The objective of this study was to identify phytoseiid mites from Mato Grosso do Sul associated with T. evansi, to identify promising biological control agents for T. evansi in Africa. A survey was conducted in October – November 2002, sampling more than 70 plant species of 30 families, including 16 solanaceous species. The results of this survey provide some additional information to the scant knowledge on the Phytoseiids from Mato Grosso do Sul. In total, 471 Phytoseiids were collected, belonging to 12 Amblyseiinae and two Phytoseiinae species. The most frequent and abundant species was Euseius citrifolius Denmark and Muma, followed by Euseius concordis (Chant). Also, 3,493 tetranychids were found. Tetranychus evansi was found in Aquidauna on Solanum americanum (Miller), associated with E. citrifolius and Typhlodromalus aripo De Leon; in Corumba, on S. americanum associated with E. concordis and Neoseiulus idaeus Denmark and Muma; and in Dourados, on Solanum lycopersicum (L.), associated with E. citrifolius, Proprioseiopsis mexicanus (Garman) and Proprioseiopsis ovatus (Garman). However, none of the Phytoseiids found are considered to be a promising biological control agent of T. evansi, based on both their inconsistent association with the pest and on available information about each species.

  • Rates of description of Phytoseiidae mite species (Acari: Mesostigmata): space, time and body size variations
    Biodiversity and Conservation, 2012
    Co-Authors: Marie-stéphane Tixier, Serge Kreiter, Martial Douin, G.j. De Moraes
    Abstract:

    This study aims to analyse the degree of completeness of world inventory of the mite family Phytoseiidae and the factors that might determine the process of species description. The world data set includes 2,122 valid species described from 1839 to 2010. Species accumulation curves were analysed. The effect of localisation (latitude ranges) and body size on the species description patterns over space and time was assessed. A low proportion of species seems remain to be described, but this trend could be explained by a critical reduction in the number of specialists dedicated to the study of those mites. In addition, this trend refers to the areas where Phytoseiids have been well studied around the world, and it may change considerably if the study of these mites would be intensified in some areas. The number of newly described species is lower near the tropics, and their body size is also smaller. Differences in body size were noted between the three sub-families of Phytoseiidae, the highest mean body lengths of adult females being observed for Amblyseiinae, the most diverse family. In the future, collections would have certainly to take into consideration such conclusions for instance in using more adequate optical equipment especially for field collections. The decrease in the number of phytoseiid mite described was confirmed and the factors that could explain such a trend are discussed. Information for improving further inventories is provided and discussed, especially in relation to sampling localization and study methods.

B.a. Croft - One of the best experts on this subject based on the ideXlab platform.

  • plants and leaf characteristics influencing the predaceous mite kampimodromus aberrans acari phytoseiidae in habitats surrounding vineyards
    Environmental Entomology, 2002
    Co-Authors: Serge Kreiter, B.a. Croft, Marie-stéphane Tixier, P Auger, D Barret
    Abstract:

    We sampled phytoseiid mites (densities, diversity, and age structure) on several plants located in four uncultivated areas surrounding vineyards over 3 yr to determine how leaf structure affects populations. The plant composition of these areas greatly influenced the numbers and species of Phytoseiids present. The relationships between leaf structure (trichome, pollen densities, number, and structure of domatia, leaf surface) and Kampimodromus aberrans (Oudemans) densities also were studied. The frequency of occurrence and the abundance of K. aberrans per cm2 were correlated to high trichome densities. A complex phylloplane (many hairs and shelters or domatia) could confer a competitive advantage to K. aberrans over other phytoseiid mite species. The number and the rating of domatia were important to K aberrans development; high proportions of immatures were observed only on plants with these structures. Pollen densities were significantly correlated to trichome densities; domatia structure had only a somewhat lesser effect. Our study shows that dense trichome and pollen levels are favorable to the development of K. aberrans populations and add perspective on the influence of domatia on this important predaceous mite.

  • classification of generalist or specialist life styles of predaceous phytoseiid mites using a computer genetic algorithm information theory and life history traits
    Environmental Entomology, 1999
    Co-Authors: Hangkwang Luh, B.a. Croft
    Abstract:

    A computer-based genetic algorithm with an information-based model selection criterion (Akaike’s information criterion [ AIC ]) was used to identify biological traits to classify 4 life style types of 13 representative predaceous phytoseiid mites. As a form of optimization, the genetic algorithm is a computational problem-solving algorithm that mimics Darwinian evolution factors such as fitness, selection, recombination (crossovers), and mutation. The genetic algorithm seeks best solutions to an objective function from many possibilities. Each subset model of traits is treated as a living organism. The AIC is calculated for each model as its fitness value. The genetic algorithm searches for the “best” subset within the landscape of all AIC fitness values to find the best combination. Of 24 provisional traits for 13 species of Phytoseiids, 7, including those for developmental rates and 6 individual categories of prey-food proportions were always included in best solutions for the classification of the 4 life style types that previously were identified. These well-studied traits and other less-well studied traits show potential as useful indicators of life style types. Other means to simultaneously optimize selection of life style types and biological traits are discussed.

  • Intra- and interspecific predation on four life stage groups by the adult females of Metaseiulus occidentalis, Typhlodromus pyri, Neoseiulus fallacis and Amblyseius andersoni
    Experimental & Applied Acarology, 1996
    Co-Authors: B.a. Croft
    Abstract:

    Do adult females of oligophagous species such as Neoseiulus fallacis (Garman) and Metaseiulus occidentalis (Nesbitt) show less intra- and interspecific predation on Phytoseiids when other foods are scarce than polyphagous species such as Amblyseius andersoni Chant and Typhlodromus pyri Scheuten? We caged single adult females of each species without food with ten of their own eggs or larvae, with ten eggs or larvae of the other species or with ten nymphs or adult females of M. occidentalis ( T. pyri for M. occidentalis ). We assessed the ambulatory activity, survival time, egg levels and prey loss in each test. Polyphages (in particular T. pyri ) lived longer than oligophages (in particular N. fallacis ) without food. The small T. pyri detected its own stages and benefited most by feeding on small active stages of other species. Amblyseius andersoni , the largest mite, fed and gained the most of any species when held with nymphs and female adults. Metaseiulus occidentalis fed on eggs of all four species to enhance survival. The large hyperactive N. fallacis gained the least from these behaviours. Each mite seemed uniquely adapted to survive conditions of scarce prey and these behaviours may explain their roles in phytoseiid mite complexes. Overall, oligophagous adult females fed less and gained less by feeding on Phytoseiids than did polyphagous adult females.

  • differential impact of egg predation by zetzellia mali acari stigmaeidae on metaseiulus occidentalis and typhlodromus pyri acari phytoseiidae
    Experimental and Applied Acarology, 1996
    Co-Authors: Ian V Macrae, B.a. Croft
    Abstract:

    The differential impact of Zetzellia mali on the Phytoseiids Metaseiulus occidentalis and Typhlodromus pyri was studied in the laboratory and by analysis of population from orchard plots that contained either phytoseiid, similar numbers of prey mites and high or low densities of Z. mali. Five hypotheses were evaluated to explain why Z. mali had more impact on M. occidentalis in the field than on T. pyri. Given equal opportunity, Z. mali adult females did not consume more M. occidentalis eggs than T. pyri eggs nor did adult females of either phytoseiid inflict greater mortality on Z. mali eggs or larvae through attack or consumption. There was no difference in the within-tree association of Z. mali adult females with eggs of either phytoseiid species nor were there differences in the way prey mites (all life stages) were spatially partitioned between adult female Z. mali as compared with adults and deutonymphs (combined) of either phytoseiid. The foraging area of adult female Z. mali and the oviposition locations of the two Phytoseiids from both field and laboratory data were compared using spatial statistics. Metaseiulus occidentalis laid significantly more eggs in the primary foraging area of adult female Z. mali than T. pyri. This was the only factor identified which may explain the greater impact of Z. mali on M. occidentalis. The impact of these interspecific effects on the persistence of predatory mite guilds and biological control are discussed.

  • influence of temperature on interspecific predation and cannibalism by metaseiulus occidentalis and typhlodromus pyri acarina phytoseiidae
    Environmental Entomology, 1993
    Co-Authors: Ian V Macrae, B.a. Croft
    Abstract:

    Interspecific predation and cannibalism and associated rates of oviposition were assessed for adult female Metaseiulus occidentalis (Nesbitt) and Typhlodromus pyri Scheuten when provided nonlimiting amounts of either eggs, larvae, protonymphs, or deutonymphs. Tests with all four stages of Phytoseiids and larvae of Tetranychus urticae Koch were carried out at 25°C. At 15 and 12.5°C, only larvae of Phytoseiids and larvae of T. urticae were prey items. Predation by T. pyri was higher than by M. occidentalis at 12.5 and 15°C but more similar at 25°C. M. occidentalis did not feed appreciably on phytoseiid larvae at 15 and 12.5°C. Neither phytoseiid oviposited at 12.5°C when fed phytoseiid larvae, but T. pyri did at 15°C. We concluded that T. pyri was a more active predator at low temperatures. Early-season predation on M. occidentalis immatures by T. pyri could contribute to displacement of M. occidentalis from apple orchards in western Oregon.

Urbaneja Bernat Pablo - One of the best experts on this subject based on the ideXlab platform.

  • Efectos de las condiciones abióticas sobre las interacciones entre tres depredadores de Tetranychus urticae con distintos hábitos alimenticios
    'Universitat Jaume I', 2017
    Co-Authors: Urbaneja Bernat Pablo
    Abstract:

    Tetranychus urticae es uno de los ácaros más perjudiciales que afectan a los huertos de cítricos en España, favorecido por altas temperaturas y baja humedad relativa. Sus principales enemigos naturales en este agro-ecosistema pertenecen a la familia Phytoseiidae entre los que destacan Euseius stipulatus, Neoseiulus californicus y Phytoseiulus persimilis. El cambio climático podría desencadenar brotes de T. urticae. Sin embargo, no se sabe cómo este fenómeno afectaría el sistema tritrófico clementina - T. urticae - fitoseidos. El objetivo principal de esta tesis ha sido evaluar cómo las condiciones abióticas afectan el rendimiento de las tres especies de fitoseidos, en diferentes módulos comunitarios bajo condiciones de campo y laboratorio. Nuestros resultados muestran que el cambio climático puede poner en peligro el control biológico de T. urticae en clementinos, favoreciendo estas condiciones abióticas a T. urticae, y causando efectos negativos sobre sus enemigos naturales clave, directamente o a través de sus interacciones.Tetranychus urticae is one of the most damaging mites affecting citrus orchards in Spain, favored by high temperatures and low relative humidity. Its main natural enemies in this agro-ecosystem belong to the Phytoseiidae family, namely Euseius stipulatus, Neoseiulus californicus and Phytoseiulus persimilis. For this reason, Climate Change could trigger outbreaks of T. urticae. However, it is not known how this phenomenon would affect the tri-trophic system clementine - T. urticae - Phytoseiids. The main objective of this thesis has been to explore how abiotic conditions (temperature and relative humidity) affect the performance of the three phytoseiid species mentioned above on different community modules in field and laboratory conditions. Our results have shown that Climate Change can actually jeopardize biological control of T. urticae in clementines, because of the combined positive effect on T. urticae, partly through its host plant, and the negative effects on its key phytoseiid natural enemies, either directly or through their interactions

  • Efectos de las condiciones abióticas sobre las interacciones entre tres depredadores de Tetranychus urticae con distintos hábitos alimenticios
    'Universitat Jaume I', 2017
    Co-Authors: Urbaneja Bernat Pablo
    Abstract:

    Tetranychus urticae es uno de los ácaros más perjudiciales que afectan a los huertos de cítricos en España, favorecido por altas temperaturas y baja humedad relativa. Sus principales enemigos naturales en este agro-ecosistema pertenecen a la familia Phytoseiidae entre los que destacan Euseius stipulatus, Neoseiulus californicus y Phytoseiulus persimilis. El cambio climático podría desencadenar brotes de T. urticae. Sin embargo, no se sabe cómo este fenómeno afectaría el sistema tritrófico clementina - T. urticae - fitoseidos. El objetivo principal de esta tesis ha sido evaluar cómo las condiciones abióticas afectan el rendimiento de las tres especies de fitoseidos, en diferentes módulos comunitarios bajo condiciones de campo y laboratorio. Nuestros resultados muestran que el cambio climático puede poner en peligro el control biológico de T. urticae en clementinos, favoreciendo estas condiciones abióticas a T. urticae, y causando efectos negativos sobre sus enemigos naturales clave, directamente o a través de sus interacciones.Tetranychus urticae is one of the most damaging mites affecting citrus orchards in Spain, favored by high temperatures and low relative humidity. Its main natural enemies in this agro-ecosystem belong to the Phytoseiidae family, namely Euseius stipulatus, Neoseiulus californicus and Phytoseiulus persimilis. For this reason, Climate Change could trigger outbreaks of T. urticae. However, it is not known how this phenomenon would affect the tri-trophic system clementine - T. urticae - Phytoseiids. The main objective of this thesis has been to explore how abiotic conditions (temperature and relative humidity) affect the performance of the three phytoseiid species mentioned above on different community modules in field and laboratory conditions. Our results have shown that Climate Change can actually jeopardize biological control of T. urticae in clementines, because of the combined positive effect on T. urticae, partly through its host plant, and the negative effects on its key phytoseiid natural enemies, either directly or through their interactions.Programa de Doctorat en Cièncie

Kreiter S. - One of the best experts on this subject based on the ideXlab platform.

  • Mites (Acari) of cassava (Manihot esculenta Crantz) habitat in southern Africa
    'Informa UK Limited', 2018
    Co-Authors: Hanna R., G.j. De Moraes, Kreiter S., Phiri G., Jone A.
    Abstract:

    Consideration of possible side-effects of exotic biological control agents on their new environments is a necessary step in classical biological control programs. The evaluation of such effects usually requires the knowledge of the fauna present in those environments prior to introduction of control agents. This paper presents the first of a series of studies to evaluate the safety of a classical biological control program of the cassava green mite Mononychellus tanajoa (Bondar) in Mozambique and Malawi involving the introduction of Typhlodromalus aripo DeLeon, a predatory mite of the family Phytoseiidae. The objective of this study was to determine the mite fauna of cassava and of some of the visually most common plant species in or around cassava fields in those countries. The study was conducted at different occasions in the dry and rainy seasons, in 26 fields in Mozambique and 20 fields in Malawi representing a range of ecosystems. Twenty-one phytoseiid species were recorded in Mozambique and 32 in Malawi. On cassava, the dominant Phytoseiids were Euseius baetae (Meyer & Rodrigues), Euseius bwende (Pritchard & Baker) and Typhlodromalus saltus(Denmark & Muma) in Mozambique, and Euseius fustis (Pritchard & Baker), Iphiseius degenerans (Berlese) and T. saltus in Malawi. On other plants, the dominant Phytoseiids were Euseius baetae, Amblyseius sundi Pritchard & Baker and Parphytoseius horrifer (Pritchard & Baker) in Mozambique, and I. degenerans,Euseius magucii (Meyer & Rodrigues) and Euseius orygmus (Ueckermann & Loots) in Malawi. Several of the most common plants associated with cassava were observed to harbor phytoseiid species that were also found on the latter. Those plants may be important as reservoirs of such predators when conditions are not appropriate for them to live on cassava. This seemed to be particularly true for 6 Phytoseiids in Mozambique (A. sundi, E. magucii, P. horrifer, Typhlodromalus spinosus(Meyer & Rodrigues), Typhlodromips shi (Pritchar & Baker) and Neoseiulus teke (Pritchard & Baker)), and 6 Phytoseiids in Malawi (E. orygmus, Phytoseius amba Pritchard & Baker, T. shi, Typhlodromus (Anthoseius) kikuyuensis Swirski & Ragusa, Typhlodromus (Anthoseius) malawiensis Annou, Moraes & Hanna and N. teke), that were found on cassava at the end of the rainy season, but only on other plants in the dry season. M. tanajoa was the dominant mite species on cassava in both countries in addition to the Phytoseiids; few other species were found on that plant in either country. A larger diversity of mites in addition to Phytoseiids was found on other plants, but always at low numbers. Phytoseiids diversity and abundance varied between savannah and forest zones. These variations are likely due differences in biotic and abiotic factors between the two zones

  • Native phytoseiid mites as indicators of non-target eVects of the introduction of Typhlodromalus aripo for the biological control of cassava green mite in Africa
    'Elsevier BV', 2018
    Co-Authors: Zannou I.d., G.j. De Moraes, Hanna R., Kreiter S., Phiri G., Agboton B., Jone A.
    Abstract:

    Article purchasedThe need to evaluate non-target effects of classical biological control of arthropod pests has received considerable attention in recent years. We determined with repeated field surveys the changes in abundance and distribution of the phytoseiid mite fauna in cassava fields resulting from the introduction of the neotropical phytoseiid Typhlodromalus aripo into two countries—Malawi and Mozambique—in southern Africa for the biological control of Mononychellus tanajoa. Typhlodromalus aripo abundance was similar, while the abundance of the target pest M. tanajoa declined progressively, during the 2 years after the introduction of T. aripo into the target countries. We did not detect any changes in the abundance of the most common native Phytoseiids mites—Euseius baetae, Euseius bwende and Ueckermannseius saltus—on cassava in Mozambique. In contrast, the abundance of two of the most common native Phytoseiids, Euseius fustis and Iphiseius degenerans, on cassava in Malawi were apparently facilitated—i.e., their abundance was enhanced by the introduction of T. aripo; while the abundance of a third species, U. saltus, was not affected. For only one species, E. baetae, within-plant distribution shifted to the lower parts of the cassava canopy as a result of the introduction of T. aripo, which resides in the upper parts of the cassava canopy, but without any measurable negative effects on biological control of M. tanajoa. While the overall abundance of phytoseiid mites found on non-cassava vegetation was not affected by T. aripo introduction, there were some changes in relative abundance of some species in Malawi. Possible mechanism for the increase in abundance of I. degenerans and E. fustis in Malawi, and changes in within-plant distribution of E. baetae and I. degenerans in Mozambique and Malawi, respectively, are discussed. The methodology developed for assessing potential non-target effects of T. aripo introduction into southern Africa has significantly advanced classical biological control efforts against an economically important cassava pest

  • Plant inhabiting phytoseiid predators of midwestern Brazil, with emphasis on those associated with the tomato red spider mite, Tetranychus evansi (Acari: Phytoseiidae, Tetranychidae)
    'EDP Sciences', 2014
    Co-Authors: Furtado I.p., Kreiter S., De Moraes G.j., Flechtmann C.h.w., Tixier M., Knapp M.
    Abstract:

    Times Cited: 0International audienceThe fauna of phytoseiid mites in the state of Mato Grosso do Sul, in midwestern Brazil, is poorly known. The tomato red spider mite, Tetranychus evansi Baker and Pritchard, is an important pest of Solanaceae in several countries, but it is usually found in low densities in Brazil. It has been hypothesized that this is due to the effect of natural enemies. The objective of this study was to identify phytoseiid mites from Mato Grosso do Sul associated with T. evansi, to identify promising biological control agents for T. evansi in Africa. A survey was conducted in October – November 2002, sampling more than 70 plant species of 30 families, including 16 solanaceous species. The results of this survey provide some additional information to the scant knowledge on the Phytoseiids from Mato Grosso do Sul. In total, 471 Phytoseiids were collected, belonging to 12 Amblyseiinae and two Phytoseiinae species. The most frequent and abundant species was Euseius citrifolius Denmark and Muma, followed by Euseius concordis (Chant). Also, 3,493 tetranychids were found. Tetranychus evansi was found in Aquidauna on Solanum americanum (Miller), associated with E. citrifolius and Typhlodromalus aripo De Leon; in Corumba, on S. americanum associated with E. concordis and Neoseiulus idaeus Denmark and Muma; and in Dourados, on Solanum lycopersicum (L.), associated with E. citrifolius, Proprioseiopsis mexicanus (Garman) and Proprioseiopsis ovatus (Garman). However, none of the Phytoseiids found are considered to be a promising biological control agent of T. evansi, based on both their inconsistent association with the pest and on available information about each species

  • Native phytoseiid mites as indicators of non-target eVects of the introduction of Typhlodromalus aripo for the biological control of cassava green mite in Africa
    2007
    Co-Authors: Zannou I.d., G.j. De Moraes, Hanna R., Kreiter S., Phiri G., Agboton B., Jone A.
    Abstract:

    Article purchasedThe need to evaluate non-target effects of classical biological control of arthropod pests has received considerable attention in recent years. We determined with repeated field surveys the changes in abundance and distribution of the phytoseiid mite fauna in cassava fields resulting from the introduction of the neotropical phytoseiid Typhlodromalus aripo into two countries—Malawi and Mozambique—in southern Africa for the biological control of Mononychellus tanajoa. Typhlodromalus aripo abundance was similar, while the abundance of the target pest M. tanajoa declined progressively, during the 2 years after the introduction of T. aripo into the target countries. We did not detect any changes in the abundance of the most common native Phytoseiids mites—Euseius baetae, Euseius bwende and Ueckermannseius saltus—on cassava in Mozambique. In contrast, the abundance of two of the most common native Phytoseiids, Euseius fustis and Iphiseius degenerans, on cassava in Malawi were apparently facilitated—i.e., their abundance was enhanced by the introduction of T. aripo; while the abundance of a third species, U. saltus, was not affected. For only one species, E. baetae, within-plant distribution shifted to the lower parts of the cassava canopy as a result of the introduction of T. aripo, which resides in the upper parts of the cassava canopy, but without any measurable negative effects on biological control of M. tanajoa. While the overall abundance of phytoseiid mites found on non-cassava vegetation was not affected by T. aripo introduction, there were some changes in relative abundance of some species in Malawi. Possible mechanism for the increase in abundance of I. degenerans and E. fustis in Malawi, and changes in within-plant distribution of E. baetae and I. degenerans in Mozambique and Malawi, respectively, are discussed. The methodology developed for assessing potential non-target effects of T. aripo introduction into southern Africa has significantly advanced classical biological control efforts against an economically important cassava pest.Danish International Development AgencyInternational Fund for Agricultural DevelopmentPeer Revie

  • Mites (Acari) of cassava (Manihot esculenta Crantz) habitat in southern Africa
    2005
    Co-Authors: Hanna R., G.j. De Moraes, Kreiter S., Phiri G., Jone A.
    Abstract:

    Consideration of possible side-effects of exotic biological control agents on their new environments is a necessary step in classical biological control programs. The evaluation of such effects usually requires the knowledge of the fauna present in those environments prior to introduction of control agents. This paper presents the first of a series of studies to evaluate the safety of a classical biological control program of the cassava green mite Mononychellus tanajoa (Bondar) in Mozambique and Malawi involving the introduction of Typhlodromalus aripo DeLeon, a predatory mite of the family Phytoseiidae. The objective of this study was to determine the mite fauna of cassava and of some of the visually most common plant species in or around cassava fields in those countries. The study was conducted at different occasions in the dry and rainy seasons, in 26 fields in Mozambique and 20 fields in Malawi representing a range of ecosystems. Twenty-one phytoseiid species were recorded in Mozambique and 32 in Malawi. On cassava, the dominant Phytoseiids were Euseius baetae (Meyer & Rodrigues), Euseius bwende (Pritchard & Baker) and Typhlodromalus saltus(Denmark & Muma) in Mozambique, and Euseius fustis (Pritchard & Baker), Iphiseius degenerans (Berlese) and T. saltus in Malawi. On other plants, the dominant Phytoseiids were Euseius baetae, Amblyseius sundi Pritchard & Baker and Parphytoseius horrifer (Pritchard & Baker) in Mozambique, and I. degenerans,Euseius magucii (Meyer & Rodrigues) and Euseius orygmus (Ueckermann & Loots) in Malawi. Several of the most common plants associated with cassava were observed to harbor phytoseiid species that were also found on the latter. Those plants may be important as reservoirs of such predators when conditions are not appropriate for them to live on cassava. This seemed to be particularly true for 6 Phytoseiids in Mozambique (A. sundi, E. magucii, P. horrifer, Typhlodromalus spinosus(Meyer & Rodrigues), Typhlodromips shi (Pritchar & Baker) and Neoseiulus teke (Pritchard & Baker)), and 6 Phytoseiids in Malawi (E. orygmus, Phytoseius amba Pritchard & Baker, T. shi, Typhlodromus (Anthoseius) kikuyuensis Swirski & Ragusa, Typhlodromus (Anthoseius) malawiensis Annou, Moraes & Hanna and N. teke), that were found on cassava at the end of the rainy season, but only on other plants in the dry season. M. tanajoa was the dominant mite species on cassava in both countries in addition to the Phytoseiids; few other species were found on that plant in either country. A larger diversity of mites in addition to Phytoseiids was found on other plants, but always at low numbers. Phytoseiids diversity and abundance varied between savannah and forest zones. These variations are likely due differences in biotic and abiotic factors between the two zones.Danish International Development AgencyInternational Fund for Agricultural DevelopmentPeer Revie

Peter Schausberger - One of the best experts on this subject based on the ideXlab platform.

  • predation preferences and discrimination between con and heterospecific prey by the phytoseiid mites phytoseiulus persimilis and neoseiulus californicus
    Biocontrol, 1999
    Co-Authors: Andreas Walzer, Peter Schausberger
    Abstract:

    Discrimination between and predation preference for con- or heterospecific larvae was examined for adult females of P. persimilis and N. californicus in plexiglass cages with and without their primary prey T. urticae. Rates of intra- and interspecific predation on larvae were measured for females held on leaves and provided with excess amounts of spider mites. Females of the generalist N. californicus distinguished con- and heterospecific larvae and preferred to prey upon the latter. Females of the specialist P. persimilis appeared to lack discrimination ability and fed equally on con- and heterospecifics. When spider mites and Phytoseiids were offered simultaneously, all P. persimilis females chose to first attack T. urticae, whereas N. californicus females attacked both tetranychids and heterospecific Phytoseiids. Females of both predators preyed upon phytoseiid larvae when held on leaves with surplus T. urticae: while P. persimilis fed on both con- and heterospecifics, N. californicus attacked larvae of P. persimilis but avoided cannibalizing larvae. The different behaviors of P. persimilis and N. californicus are discussed with regard to different predation types (generalists vs. specialists) and the possible consequences of mixed release for biological control of spider mites in greenhouses.

  • Juvenile Survival and Development in Euseius Finlandicus, Typhlodromus Pyri and Kampimodromus Aberrans (Acari: Phytoseiidae) Feeding on Con- and Heterospecific Immatures
    Experimental & Applied Acarology, 1999
    Co-Authors: Peter Schausberger
    Abstract:

    Juvenile survival and development in Euseius finlandicus (Oudemans), Typhlodromus pyri Scheuten and Kampimodromus aberrans (Oudemans) feeding on con- and heterospecific phytoseiid immatures were investigated in the laboratory at 25 ± 1 °C and 65 ± 5% RH. More than 50% of T. pyri protonymphs preying on larvae of K. aberrans or E. finlandicus reached the adult stage. The mean developmental time of T. pyri from the protonymphal stage to adulthood was 6.3 days when feeding on K. aberrans and 7.5 days when feeding on E. finlandicus. The majority (approximately 90%) of K. aberrans protonymphs feeding on larvae of T. pyri or E. finlandicus died before reaching the deutonymphal stage; in both cases only one individual completed juvenile development. Euseius finlandicus larvae require food to reach the subsequent life stage, in contrast to larvae of T. pyri and K. aberrans, which usually do not feed at all: 10% of E. finlandicus immatures feeding on larvae of K. aberrans or T. pyri completed juvenile development (mean developmental time from larva to adult 7.0 and 6.7 days, respectively). Cannibalizing immatures of T. pyri and K. aberrans were able to reach adulthood, whereas those of E. finlandicus were not. Unfed immatures of T. pyri lived longer than the corresponding stages of E. finlandicus and K. aberrans. The present study indicates that phytoseiid immatures are suitable prey for developing stages of polyphagous Phytoseiids. Since E. finlandicus, T. pyri and K. aberrans partly inhabit the same plant species, their immatures can be regarded as potential prey for competitive Phytoseiids in times of food scarcity.

  • inter and intraspecific predation on immatures by adult females in euseius finlandicus typhlodromus pyri and kampimo dromus aberrans acari phytoseiidae
    Experimental and Applied Acarology, 1997
    Co-Authors: Peter Schausberger
    Abstract:

    In a series of experiments, the interspecific predation and cannibalism on immatures by the adult females of Euseius finlandicus, Kampimodromus aberrans and Typhlodromus pyri were examined under laboratory conditions. The three species showed differing tendencies to prey on each other's motile immature stages. Euseius finlandicus females consumed more larvae and protonymphs than the females of T. pyri and K. aberrans. In cages without free water E. finlandicus ate a range of 6.51 larvae or 5.31 protonymphs of T. pyri and 5.27 larvae or 5.95 protonymphs of K. aberrans per female per day. Kampimodromus aberrans and T. pyri females exhibited a greater tendency to prey on heterospecifics than on conspecifics. When feeding on phytoseiid immatures and without free water, T. pyri females survived longer and laid more eggs than the females of E. finlandicus and K. aberrans. Adult females of E. finlandicus and T. pyri having free water and preying on heterospecific protonymphs were able to maintain egg laying during the whole experimental period of 12 days. The females of all three species had difficulties in piercing phytoseiid eggs, and the number of sucked eggs per female per day was low. Kampimodromus aberrans females ate 0.48 eggs of T. pyri daily, which was the highest recorded number. The great tendency to interspecific predation on motile immature Phytoseiids by the females of E. finlandicus is discussed with regard to the dominance of this species on deciduous trees and bushes in Austria.