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Ecological studies and management of the red spider mite, Oligonychus mangiterus (Rahman and Sapra) infesting mango orchards near Cairo in Egypt were carried out for two years. Population behaviour of the pest was influenced by climatic conditions, host preference, predation and vertical distribution. About 14 & 15 generations were recorded for 0. mangiferus on Hindi and 16 & 14 generations on Alphonso cultivars during the two successive years respectively. Leaves at top level of both mango cultivars were found preferable to the mite infestation than those at the middle and bottom. Alphonso mango trees were nearly more susceptible to mite pest compared with Hindi cultivar. One acaricide application was sufficient to suppress the mite outbreak below the economic level when it applied as mite population started to increase.

Life history and prey consumption of the predatory stigmaeid mite Agistemus olivi Romeih, as affected by feeding on the motile stages of the olive bud mite Aceria oleae Nalepa and the olive rust mite Tegolophus hassani Keifer (Acari : Eriophyidae), has been studied for the first time at different temperatures and 70–75% r.h. A greater capability was shown for consuming the olive bud mite than the olive rust mite and the former prey relatively induced more fecundity. The rise of different temperatures from 20°C to 25°C and 30°C shortened development and increased reproduction and prey consumption. The maximum reproduction (6.92 and 6.08 eggs ♀ day) was recorded at the higher temperature, while the minimum reproduction (1.50 and 1.30 eggs ♀ day) was observed for A. oleae and T. hassani, respectively.

Ecological studies were carried out on seven tenuipalpid mites: Cenopalpus pulcher, C. lanceolatistae, Brevipalpus obovatus, B. phoenicis, B. californicus, Tenuipalpus punica and T. granati infesting deciduous fruit trees in U.A.R. and their predators for one year. C. lanceolatisetae, C. pulcher, and T. granati were encountered on pear, apple and grape respectively. B. obovatus was noted infesting quince and apple trees but preferring the first host. B. phoenicis was found infesting only pear trees at the Tahreer orchard. In Nile Delta, T. punica and C. pulcher were regarded as persistent pests on pomegranate and apple respectively, while B. californicus was noted as an occasional pest on several hosts. Zusammenfassung Okologische Untersuchungen uber Milben an Obstbaumen in Unteragypten Es wurden okologische Untersuchungen an sieben Milbenarten der Fam. Tenuipalpidae: Cenopalpus pulcher, C. lanceolatisetae, Brevipalpus obovatus, B. phoenicis, B. californicus, Tenuipalpus punica und T. granati sowie ihren Feinden durchgefuhrt. C. lanceolatisetae, C. pulcher und T. granati bewohnten Apfel-, Birnen- und Grapefrucht-Baume. B. obovatus befiel Quitte und Apfel unter Bevorzugung der ersteren. B. phoenicis wurde nur an Birnbaumen im Tahreer-Distrikt gefunden. Im Nildelta traten T. punica und C. pulcher als Schadlinge an Granatapfel- und Apfelbaumen auf, wahrend B. californicus als gelegentlicher Schadling verschiedener Obstbaumarten beobachtet wurde. Die rauberische Milbe Amblyseius swirskii scheint ein wichtiger Mortalitatsfaktor bei den Tenuipalpiden an Laubbaumen zu sein. Auch Pronematus ubiquitus spielt eine ahnliche Rolle. Die Dichte beider Arten war positiv mit derjenigen der Tenuipalpiden korreliert. Die Bedeutung der in geringer Anzahl gefundenen Tydeus californicus war nicht klar ersichtlich.

Studying mites associated with deciduous orchards in Egypt, fourty four mite species were recorded. Population abundance of Tetranychus cinnabarinus was affected by the prevailing climatic conditions, host preference, action of predators, pesticides and leaf age. A better understanding of some of these factors is necessary and might lead to possibilities of altering the conditions of the plant growth so as to lower the reproductive poteniality of the mite feeding on it. A control measure of one summer acaricide application throughout the year seemed to be the most successful control management of T. cinnabarinus. Zusammenfassung Uber die Wirkung okologischer und chemischer Faktoren auf die auf Obstbaumen schadlichen Milben in Agypten Bei Untersuchungen der in den Kronen agyptischer Obstbaume lebenden Milben wurden insgesamt 44 Arten gezahlt. Die die Populationsdichte der wichtigsten phytophagen Milbe Tetranychus cinnabarinus beeintlussenden Faktoren waren: Klima. Wirtspflanze, Aktivitat der rauberischen Feinde. Blattalter und Akarizide, Es ist notwendig. die Wirkung dieser Faktoren besser zu verstehen, um mit Hilfe einer Veranderung der Umweltbedingungen die Reproduktionsrate der schadlichen Milben zu reduzieren. Der ein Jahr lang angewandte Einsatz eines Sommer-Akarizids scheint zur Zeit die erfolgreichste Methode zur Eindammung von T. cinnabarinus zu sein.

44 species of 17 families of mites associated with deciduous fruit trees (grape, apple, pear, quince, apricot, plum, peach, cherry, pomegranate, pecan, almond) were recorded in U.A.R. 13 species were phytophagous, 28 species were presumably predacious, and three species were presumably scavengers and fungus feeders. Zusammenfassung Ubersicht uber die in der V.A.R. auf laubabwerfenden Obstgewachsen lebenden Milben 44 Milbenarten aus 17 Familien wurden an Wein, Apfel, Birne, Quitte, Aprikose, Pflaume, Pfirsich, Kirsche, Granatapfel, Pekanus und Mandel registriert: 13 phytophage, 28 mutmaslich rauberische sowie 3 Abfall und Pilze fressende Arten. Die Milbenarten werden familienweise unter Angabe der Wirte, der Lebensweise und Haufigkeit aufgezahlt.

Two eriophyid mites, Aculops acaciae sp. n. and Tetra acaciae sp. n. are described and illustrated from Acacia arabica. The first species was found infesting flowers; while the second one was noted on well developed leaves preferring the lower surface. Relationships of the new species with other known species under the genera are discussed.

Mites associated with abandoned fig trees in Egypt were observed during a 2-year study. This study included species diversity and seasonal fluctuations as well as some biological aspects of common eriophyoid species. Three phytophagous species consisted of the fig bud mite Aceria ficus (Cotte), the fig leaf mite Rhyncaphytoptus ficifoliae Keifer and the two-spotted spider mite Tetranychus urticae Koch, representing a basic trophic level, were fed upon by three of predacious mites (Pronematus ubiquitus (McGregor), Amblyselus swirskii Athias-Henriot, Agistemus exsertus Gonzalez). Population abundance of the injurious mites were affected by the prevailing climatic conditions, action of predators and leaf age. A control measure of one summer pesticide (abamectin) application throughout the year seemed to be the most successful management of harmful mites. Life table parameters showed that the population of A. ficus multiplied 28.52 times in a generation time of 17.90 days, while R. ficifoliae population increased 16.50 times in a generation time of 14.61 days. Field and laboratory studies indicated that the viviparity is a typical character in the reproduction of R. ficifoliae.

16 species of 11 families of mites associated with fig trees in U.A.R., were recorded. 3 species were phytophagous, while 11 species were presumably predacious, and 2 species were presumably scavengers and fungus feeders. Zusammenfassung Feigenbaum-bewohnende Milben in Agypten Auf Feigenbaume im Nildelta wurden 16 Milbenarten aus 11 Familien festgestellt: 3 phytophyge, 11 wahrscheinlich rauberische und 2 wahrscheinlich Abfalle und Pilze verzehrende Arten.

The predacious mites Amblyseius gossipi El-Badry and A. swirskii Athias-Henroit developed, survived and reproduced successfully on several artificial diets. The best diet consisted of 1 g yeast, 1 g milk, 30 mg cystine, 30 mg proline, 30 mg arginine, 20 mg sucrose, 50 mg glucose, 30 mg streptomycin sulphate and droplets of sorbic acid. Mean eggs/female/day by the two predators was 0.54 and 0.30 when reared on the best diet compared to 1.21 and 0.40 when fed on a natural diet, respectively. Female longevity of A. swirskii was 84.3 days, nearly twice as long as that on a natural diet. Eggs showed no abnormalities; larvae fed on diets had normal development, and adults were comparable in size to individuals reared on a natural diet.

Two factors were investigated to determine their effect on the reproduction and sex ratios in two species of predacious mites, Amblyseius swirskii and A. gossipi, in the laboratory. These factors were starvation during the immature and adult stages as well as fertilization in excess of females. Longevity periods were greatly influenced by food deprivation programmes. A clear difference was recorded in the total number of egg production; severe food deprivation had the leading effect followed by moderate then simple. A male of both species showed a high reproductive ability for more than 17 days and was able to mate more than once in excess of females, with maximum of seven and nine times in A. gossipi and A. swirskii respectively. Zusammenfassung Zur Wirkung von Hungerphasen und Befruchtung auf die Reproduktion von Amblyseius swirskii Athias-Henriot und A. gossipi El-Badry (Acari, Phytoseiidae) Im Labor wurde die Auswirkung von zwei Faktoren auf die Reproduktion und das Geschlechterverhaltnis bei Amblyseius swirskii und A. gossipi untersucht. Diese beiden Faktoren waren einerseits Hungerphasen im Nymphen- und Adultstadium und andererseits die Befruchtungshaufigkeit bei einer Uberzahl von Weibchen. Die Lebensdauer wurde deutlich durch die Hungerphasen beeinflust. Signifikante Unterschiede konnten auf die Gesamtzahl der Eier festgestellt werden: je langer die Hungerperioden waren, desto deutlicher war der Effekt. Mannchen beider Arten waren mehr als 17 Tage fortpflanzungsfahig und begatteten bei einer Uberzahl Weibchen haufiger als einmal, maximal 7mal (A. gossipi) bzw. 9mal (A. swirskii).

The effect of single and multiple mating on longevity, fecundity at different intervals, age of female parents and sex-ratio of the predatory mite, Agistemus exsertus Gonzalez was studied. It was found that fecundity of females mated more than once was higher than among females mated only once. A positive relation was noted between the number of progency and sex-ratio at different intervals of the reproductive period. Age of females has an influence on fecundity and sex-ratio; old females decreased egg production and produced proportionally more male progeny compared with young females under constant conditions of abundant prey. Zusammenfassung Untersuchungen zur Kopulation, Eiproduktion und zum Geschlechterverhaltnis der rauberischen Milbe Agistemus exsertus Gonzalez (Acari, Stigmaeidae) Es wurde der Einflus einer einmaligen und mehrfachen Begattung auf die Lebensdauer, die Fekunditat, das Alter der Weibchen und das Geschlechterverhaltnis von Agistemus exsertus untersucht. Die Fekunditat der Weibchen, die mehrfach begattet worden waren, war hoher als bei Weibchen, die nur einmal begattet wurden. Eine positive Beziehung konnte zwischen der Nachkommenzahl und dem Geschlechterverhaltnis in verschiedenen Intervallen der reproduktiven Phase ermittelt werden. Das Alter der Weibchen hatte Auswirkungen auf die Fekunditat und das Geschlechterverhaltnis: bei alteren Weibchen nahm die Eiproduktion ab und der Anteil der mannlichen Nachkommen nahm im Vergleich zu jungen Weibchen, die bei gleichen Bedingungen gehalten wurden, proportional zu.

The predacious mite,Agistemus exsertus Gonz. was reared on 4 types of animal egg diets (eggs ofTetranychus urticae Koch,Eutetranychus orientalis Klein,Brevipalpus pulcher [C. & F.] andBemisia tabaci [Genn.]). Life table parameters of each diet (net reproduction rate [Ro], mean generation time [T], intrinsic rate of increase [rm] and finite rate of increase [erm]) were determined. Eggs ofT. urticae were found to be preferred above other egg diets as food byA. exsertus and promoted a higher rate of oviposition. The intrinsic rate of increase was 0.15 individuals/♀/day; the population multiplied 57.91 times in a generation time of 26.21 days. Rearing on eggs ofB. tabaci exhibited more attractive compared withB. pulcher. The average number of eggs consumed daily by female was 17, 12, 9 and 7 eggs ofT. urticae, E. orientalis, B. tabaci andB. pulcher respectively. In the sex ratio of the progeny, predator females fed inT. urticae andB. tabaci gave rise to more females.

Four species in the genus Amblyseius Berlese are reported from Tanzania, A. serengati sp.n., A. fustis Pritchard and Baker, A. largoensis (Muma) and A. sawaga Pritchard & Baker. Descriptions and comparisons with similar species are provided for the new species.

Resistance has developed in the tomato russet mite,Aculops lycopersici (Massee) to the organophosphate, methamidophos. Laboratory studies showed thatA. lycopersici which received methamidophos for 3 years was highly tolerant. In contrast, it was very susceptible to dicofol and pyridaphenthion, and susceptible to cypermethrin. Pyridaphenthion and dicofol had long residual activity whereas methamidophos and cypermethrin had shorter activity.

The predacious mite, Cydnodromella negevi (Swirski & Amitai) completed life cycle when fed on the tetranychid mites Eutetranychus orientalis (Klein), Tetranychus urticae Koch and pollen grains of Ricinus communis (L.) as an alternative food substance in the laboratory. The duration of the immature stages and adult stage were determined. Immature stages of C. negevi consumed in total an average of 27 E. orientalis and 34 T. urticae, whereas each day throughout her life, the adult female consumed an average of 11 of E. orientalis and T. urticae. While feeding on these prey, C. negevi laid 13 and 1.0 eggs per day. The number of eggs deposited per day increased (33 eggs/female/day) when fed on eriophyid mites. Females neither fed nor reproduced on liquid nutrients. L’acarien predateur Cydnodromella negevi (Swirski et Amitai) a acheve son cycle de vie quand il s’est nourri des acariens tetranychides Eutetranychus orientalis (Klein), Tetranychus urticae Koch et de grains de pollen de Ricinus communis (L.) comme substance alimentaire de remplacement au labratoire. Les durees des stades non murs et adulte ont ete determinees. Les stades pre-adultes consomment au total en moyenne 27 E. orientalis et 34 T. urticae par jour pendant toute leur existence, la famella adulte une moyenne de 11 E. orientalis et T. urticae. Elle pond 1.3 et 1.0 oeufs par jour. Le nombre d’oeufs deposes par jour a augmente (3.3 Oeufs/female/jour) lorsqu’il s’alimentait sur de acariens eriophyides. Les femelles ne s’alimentaient ni ne se reproduisaient sur liquide nutritif.

Abacarus cynodonis, n.sp. and Eriophyes niloticus, n.sp. (Eriophyidae: Acari) are described and illustrated from Bermuda grass, Cynodon dactylon (L.) Pers. The first lives under broadened leaf bases while the second prefers the upper leaf blade. Combined infestation of both species may cause stunted growth and twisting of the folded terminal shoots.

The predacious mite, Pachylaelaps aegyptiacus Hafez & Nasr completed life cycle when fed on eggs of housefly, Musca domestica (L.) at 25 ± 2°C and 70–80 % r.h. in the laboratory. The durations of the immature stages and of the adult stage were determined. Immature stages of P. aegyptiacus consumed in total an average of 16 eggs of housefly, whereas each day throughout her life, the adult female consumed an average of 7.6 eggs of housefly. Daily rate of single and multiple mating was 0.93 and 1.0 eggs/female respectively. Description of immature stages of the predatory mite was given. L’acarien predateur, Pachylaelaps aegyptiacus Hafez & Nasr, termine son cycle evolutif lorsqu’il est alimente en laboratoire avec oeufs de la mouche domestique Musca domestica (L.) a 25 ± 2° C et 70–80% d’hr. Les durees des stades non murs et adulte ont ete determinees. Les stades pre-adultes consomment au total en moyenne 16 oeufs de la mouche domestique, par jour pendant toute leur existance, la femella adulte une moyenne de 7,6 oeufs de la mouche domestique. Le taux journalier de porte apres accouplement simple ou multiple etait respectivement de 0,93 et 1,0 oeufs par femelle. La description des stades immatures a ete decrit.

The development was faster and reproduction was higher whenAmblyseius olivi Nasr & Abou-Awad fed on the eriophyid miteEriophyes olivi Zaher & Abou-Awad. The duration increased and reproduction decreased on the tetranychid miteTetranychus (T.) uriticae Koch. The predator female consumed daily 120 and 8 individuals ofE. olivi andT. (T.) uriticae respectively. The daily reproduction was as low as 0.6–0.3 eggs/♂/day when females were maintained on royal jelly, molasses, honey or their combinations.

The predacious mite, Hypoaspis Vacua (Michael) successfully developed from larva to adult stage when fed on eggs of housefly, Musca domestica (L.) and nymphs of acarid mite, Rhizoglyphus echinopus (Fum. & Rob.) in the laboratory. The duration of the immature stages and of the adult stage were determined. Food type greatly affected female fecundity and feeding capacity. Immature stages of H. vacua consumed in total an average of 13.6 eggs of M. domestica and 33.0 nymphs of R. echinopus, whereas each day throughout her life, the adult female consumed an average of 4.1 eggs of M. domestica and 13.23 nymphs of R. echinopus. Eggs of housefly were the most suitable diet, as it prolonged adult longevity (76.8 days) and increased female fecundity (13 eggs/female/day).

Heterotergum flacourtiae n.sp. (Eriophyidae: Acari) is described and illustrated. It was found in Giza region in spring primarily on the lower side of leaves of Flacourtia indica Merr., preferring the lower leaf surfaces.