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During a survey (March-June, 1995) of predacious mites on citrus in 30 major production areas, 25 species of phytoseiid and Anystid mites were recorded. Amblyseius pafuriensis Van der Merwe occurred almost at every sites in the Northern Transvaal and Southern Zimbabwe, A. citri (Van cer Merwe & Ryke) was most common in Central and Eastern Transvaal, A. citri and Typhlodromus crassus Van der Merwe, Natal, and A. addoensis addoensis (Van der Merwe & Ryke) and A. addoensis rubicolus (Van der Merwe & Ryke) in both Cape provinces. Regarding the whole region, A. addoensis addoensis, A. citri, A. addoensis rubicolus represented 86% of the total number of sampled predators, A. pafuriensis, T. crassus and T. rasilis Van der Merwe together represented 5% and the remaining 20 species represented 9%. The study indicated that A. pafuriensis, T. crassus and T. rasilis can be excellent biocontrol agents on citrus. [ABSTRACT FROM AUTHOR]

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Olive is a blessed and therapeutic fruit cultivated all around the globe in relatively temperate and dry regions. Keeping in view the quality and yield of the crop, use of pesticides is indispensable. Traditional pesticides used against crop enemies are effective but unsafe to environment, humans and predators. Olive fields of Saudi Arabia are the biggest in the world and facing infestation due to rapidly increasing number of diverse mite species. Recently, four mite species, Tegelophus hassani, Aceria olive, Oxycenus niloticus and Tetranychus urticae found to be causing severe damage to the plants, have been identified in the olive fields of Saudi Arabia. Huwa-San TR50 is a well-known water disinfectant and considered to be safe as its adverse effects on plants have not been reported as yet. The present study has been conducted to evaluate the use of Huwa-San TR50 as an acricide against four olive mites and two of their predators under laboratory and field conditions. Five different concentrations of Huwa-San TR50; 1000, 2000, 3000, 4000 and 5000 ppm were used based on previous studies to observe mortality of the selected phytophagous mites namely T. hassani, A. olive, O. niloticus and T. urticae. Gradual increase in mortality was observed when mites were treated with Huwa-San TR50 in the concentration range of 1000 - 5000 ppm. Optimum concentration of Huwa-San TR50 to be used against the mites was found to be 4000 ppm as there was negligible increase in mortality beyond this concentration. T. urticae was relatively resistant to Huwa-San TR50 with mortality of 76.58% at optimal concentration. Huwa-San TR50 has effectively impacted egg hatching especially in case of O. niloticus, where successful hatching was only 20%. Eggs of T. urticae are relatively resistant showing 57.97% hatching. The same trend and similar results of mortality and egg hatching were obtained under laboratory and field trials. As an essential part of this research, effect of Huwa-San TR50 was also observed on two predatory mites namely; Phytoseius plumifer and Agistemus exertus and it was found to be relatively safe to predatory mites showing mortality of 30 to 34% at optimum concentration. Again there was insignificant difference in mortality and egg hatching under field and laboratory conditions. Huwa-San TR50 being ecofriendly, safe to predatory mites and an effective acaricide against olive mites and their eggs is recommended for its commercial use in olive orchards. [ABSTRACT FROM AUTHOR]

This study demonstrates a laboratory induction of a malathion - resistant strain in Amblyseius cydnodactylon Shehata & Zaher and effect of selection on reproduction. Initially 500 sensitive females obtained from a laboratory mass culture were exposed to malathion at LC70. Subsequent selections were conducted every two generations at progressive LC70 values and number of eggs/female/day was recorded at each selection. Experiments were carried out under laboratory conditions of 24-28°C and 70-80 % R. H. The LC70 in the parent generation was 5.19 ppm and increased to 20 ppm in F4 selection generation. The dosage mortality relationships continued to increase up to a maximum of 282.3 ppm in F16. The rate of developing resistance increased from 1.75 folds in F2 to 1.97 folds in F4 and gradually reached a maximum of 54.39 folds in F16. There was an obvious decrease in reproduction corresponded to increasing resistance. For example, the number of eggs/female/day in F 16 was 8 eggs, contrasting 3 eggs in the parent generation. [ABSTRACT FROM AUTHOR]

The genus Leonseius Chant & McMurtry (Phytoseiidae: Typhlodrominae) was proposed to accommodate Typhloseiopsis regularisDe Leon, 1965, a species with a troubled taxonomic history that was previously classified in the genera Typhlodromus Scheuten, Diadromus Athias-Henriot and Chanteius Wainstein. Due to its Amblyseius-like appearance (long s4, Z4 and Z5, most other setae minute; atypical for a typhlodromine), the poor descriptions of reproductive structures (spermatheca, spermatodactyl), and probably also because at the time it was a monotypic genus, researchers over the years have based the species-level identification of Leonseius regularis mainly on dorsal and ventral idiosomal chaetotaxy and setal length. In a survey of phytoseiid mites conducted in cacao plantations (Theobroma cacao L.: Malvaceae) of the municipality of Ilhéus, Bahia, northeastern Brazil, we identified two distinct morphotypes among specimens initially identified as L. regularis. Herein we provide new morphological data for L. regularis to complement the original description and previous redescriptions, and then describe Leonseius elbanhawyi Carvalho, Ferragut & Oliveira sp. nov., from cacao, distinguishing it from L. regularis by its spermatheca and spermatodactyl. Also, the diagnosis of Leonseius is amended. [ABSTRACT FROM AUTHOR]

When females of the predacious mite Phytoseius finitimus Ribaga ingested dicofol and avermectin with the prey Eriophyes dioscoridis Soliman & Abou-Awad, the egg production sharply decreased after 120 h in the former, while continued at a lower rate in the later respectively. Dicofol was moderately toxic when ingested, although, avermectin caused mortality increased by increasing the time of exposure to treated prey. Few immatures reached maturity when fed on treated prey with dicofol, contrasting better development and less immature mortality on avermectin treated prey. Zusammenfassung Untersuchungen über die Überlebensrate, Reproduktion und Entwicklung der räuberischen Milbe, Phytoseius finitimus (Acari, Phytoseiidae) nach Fütterung mit Dicofol- und Avermectin-behandelten Beutetieren Bei weiblichen Raubmilben von Phytoseius finitimus, die über die Beutetiere ( Eriophyes dioscoridis) Dicofol und Avermectin aufnahmen, konnte man beim ersten Präparat eine deutliche Abnahme der Eiproduktion ab 120stündiger Fraßzeit feststellen. Beim zweiten Präparat blieb die Eiproduktion auch bei längerer Fraßzeit erhalten, allerdings auf niedrigerem Niveau. Während bei zunehmender Fütterungszeit mit Avermectin-behandelten Beutetieren die Wirkung auf die Raubmilbe anstieg, zeigte Dicofol diesbezüglich unterschiedliche Wirkungen. Wenige Tiere erreichten das erwachsene Stadium, wenn sie während ihrer Entwicklung mit Dicofol-behandelten Beutetieren gefüttert wurden, dagegen zeigte sich bei Avermectin eine vergleichsweise bessere Entwicklung und geringere Mortalität während der Entwicklung. [ABSTRACT FROM AUTHOR]

A total of 23,319 individuals representing 26 insect species were obtained from 1,063 cones of Abies alba Mill. in 1982-1986. This material originated from the Roztocze National Park in Poland where the natural range of European fir reaches its north eastern boundary. The coenotic groups of insects have been given and the indexes of domination (D), stability of incidences (C), species diversity (d), and Agrell's index of species co-existence (Ag) have been calculated. Zusammenfassung Erste Untersuchungen über die Entomofauna der Tannenzapfen (Abies alba Mill.) im Roztocze-National-Park in Polen Aus Tannenzapfen, gesammelt im Roztocze-National-Park in Polen, wo die nordöstliche Grenze des natürlichen Verbreitungsgebietes der Tanne verläuft, wurden in den Jahren 1982-1986 26 Insektenarten gewonnen. Sie gehören 6 Ordnungen an: Heteroptera, Coleoptera, Raphidioptera, Hymenoptera, Lepidoptera und Diptera. Unter ihnen waren die Zweiflügler und Hautflügler mit 17054 und 5443 Exemplaren am häufigsten vertreten. Es werden coenotische Gruppen von Insekten gebildet und mittels ökologischer Indikatoren charakterisiert. Zu den dominierenden Arten gehörten: Earomyia impossibile Morge, Resseliella piceae Seitn., Mesopolobus pinus Hussey, Lycoriella solani Winn. und Cartodere filum Aubé. Die Arten höchster Dominanz in den Tannenzapfen waren: Earomyia impossibile, Barbara herrichiana, Resseliella piceae und Megastigmus suspectus. Die Artendiversion war am stärksten innerhalb der Parasiten und Räuber der konofagischen und seminifagischen Insekten. Bezogen auf den Agrell'schen Koexistenzindikator zeigten sich Earomyia impossibile und Resseliella piceae am stärksten miteinander verbunden. [ABSTRACT FROM AUTHOR]

Interaction of soil predacious mites and citrus nematodes (parasitic and saprophytic), in citrus orchard under different regime of fertilizers; Effect on the population densities and citrus yield. During a course of study on the predacious mites and their relationships with citrus nematodes, there were several population interactions, greatly varied according to the regime of fertilizers. In general the presence of organic manure encourage the population of predacious mites to increase, although decreasing the portion of organic manure discourage the populations. There were several positive interactions between both populations and that of predacious mites over exploited the nematode populations in several cases. Yield was almost the same under the different combinations, although the quality as measured by fruit size, weight/fruit, diameter/fruit and total solible solids was better under organic manure regime. [ABSTRACT FROM AUTHOR]

Effect of the nematicide carbofuran on the population development of the citrus parasitic nematodeTylenchulus semipenetrans and predacious soil mites in citrus orchard under organic manure regime of fertilization. In an Egyptian citrus orchard under farmyard manure regime of fertilization an experiment was conducted for three successive seasons (1993–1995) to investigate the potency of the nematicide carbofuran against the population of the citrus parasitic nematodeTylenchulus semipenetrans Cobb. and any side-effects on predacious soil mites. An initial reduction inT. semipenetrans populations was observed after application, although a remarkable increase in the population occurred afterwards. In contrast, the average number of predators decreased, particularly in 1995. In organic plots without nematicide, predators increased to great numbers andT. semipenetrans caused negligible injury. In the fertilizer-free treatment, theT. semipenetrans population was low although that of predacious mites was high. The study indicated that carbofuran treatments reduced the population of predacious soil mites and in their absence the population of the parasitic nematode,T. semipenetrans was likely to increase. [ABSTRACT FROM AUTHOR]

Effect of the nematicide carbofuran on the population development of the citrus parasitic nematode Tylenchulus semipenetrans and predacious soil mites in citrus orchard under organic manure regime of fertilization. In an Egyptian citrus orchard under farmyard manure regime of fertilization an experiment was conducted for three successive seasons (1993-1995) to investigate the potency of the nematicide carbofuran against the population of the citrus parasitic nematode Tylenchulus semipenetrans Cobb. and any side-effects on predacious soil mites. An initial reduction in T. semipenetrans populations was observed after application, although a remarkable increase in the population occurred afterwards. In contrast, the average number of predators decreased, particularly in 1995. In organic plots without nematicide, predators increased to great numbers and T. semipenetrans caused negligible injury. In the fertilizer-free treatment, the T. semipenetrans population was low although that of predacious mites was high. The study indicated that carbofuran treatments reduced the population of predacious soil mites and in their absence the population of the parasitic nematode, T. semipenetrans was likely to increase. [ABSTRACT FROM AUTHOR]