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Background The tomato russet mite (TRM), Aculops lycopersici, and powdery mildew (PM), Oidium neolycopersici, are two major problems in tomato cultivation for which no effective biocontrol solutions exist to date. In a greenhouse compartment, we investigated the potential of preventatively establishing the iolinid omnivorous mite Pronematus ubiquitus on potted tomato plants to control both pest and pathogen simultaneously. Results Using Typha pollen, P. ubiquitus established well on tomato plants, with numbers reaching up to 250 motiles per tomato leaflet. The built-up population was capable of controlling subsequent infestations with both TRM and PM. This represents the first report of an arthropod protecting a crop against pests as well as disease. Conclusion The implementation of P. ubiquitus in tomato crops could be a real game-changer as it eliminates the need for repeated pesticide use or sulphur applications. The finding that arthropods can effectively control diseases opens up new opportunities for biological crop protection.

The conservation status of an ecosystem is checked by studying the composition and diversity of the organisms that interact in trophic chains. The aim of this study was to evaluate the biodiversity of mites associated to Capsicum annuum L. var glabriusculum (Solanaceae) at three sampling sites corresponding to two Protected Natural Areas (PNA) in Tamaulipas state, Mexico. Samplings were carried out in “Cañón de la Peregrina” and “Altas Cumbres” situated in the PNA "Altas Cumbres" and “Ojo de Agua”, located in the "El Cielo" Biosphere Reserve. Mite diversity was H = 1.09 ± 0.14 in Ojo de Agua, and it was H = 1.08 ± 0.08 and H = 1.11 ± 0.06 in Altas Cumbres and Cañón de la Peregrina, respectively. A total of 47 species were identified belonging to 35 genera of 18 families associated to C. annuum L. var glabriusculum in Mexico. Predatory mite richness was higher than that of generalist and phytophagous mites (31, 11 and 5 species, respectively) for the two ANP. The similarity index of Jaccard between OA–AC (IJ = 0.257; P < 0.05), CP–AC (IJ = 0.293; P < 0.05) and AC–CP (IJ = 0.324; P < 0.05) was low. Pseudopronematalus sp. 4 (Iolinidae) was predatory mite most abundant in both ANP (Pi = 9.311); followed by Metaseiulus (Metaseiulus) negundinis (Denmark) (Phytoseiidae) only for ANP “Altas Cumbres” (Pi = 1.004). While for phytophagus mite, Aculops lycopersici (Tryon) (Eriophyidae) and Tetranychus merganser Boudreaux (Tetranychidae) presented the highest abundances in all sites (Pi = 79.919 and 5.142, respectively). The high number of mites species associated to chile piquín suggests stability in the PNA despite anthropogenic activities, and that the PNA works as a mite reservoir.

Aculops lycopersici (Massee) causes plant desiccation and severe damage to tomato (Lycopersicon esculentum Mill) fruit, resulting in serious economic loss. The objective of the study was to determine the incidence of damage to fruit by A. lycopersici. Three varieties of tomato (SUN 7705, CID, and V305 F1) were used. Variety V305 F1 had the greatest index of damaged fruit (1.6852a), lowest index of useful fruit, (2.1878a) and least average weight per fruit (302.97a) of the three varieties. CID was least affected. The middle stratum had the greatest index of damaged fruit (2.3070a), lowest index of useful fruit, (1.5660b), and least average weight per fruit (254.89b) of the three strata. The lower stratum was least affected.

Studies on the life history and life table parameters of Neoseiulus cucumeris Oudemans (Acari: Phytoseiidae) were carried out under laboratory conditions of 25 ± 1 °C and 65 ± 5% RH; 30 ± 1 °C and ...

The mite family Phytoseiidae contains predatory species used in biological control. However, among the 2,521 valid species, only a few are presently considered for pest management. The study focuses on a species, frequently observed in agrosystems, but whose biology is almost totally unknown: Typhlodromus (Anthoseius) recki. The objectives were to assess its distribution and to determine under laboratory conditions: (i) the development of three populations fed on three tomato pests (Tetranychus urticae, T. evansi, Aculops lycopersici), (ii) the dispersion along the tomato stem, and (iii) the dispersion from mint to infested tomato leaf discs. Based on its distribution, this species seems to be adapted to Mediterranean climate, and is preferentially found on Boraginaceae, Solanaceae, Asteraceae and Lamiaceae. Results show that T. (A.) recki is a generalist predator, with good performance regarding the number of prey consumed. Differences were observed between the populations considered; one population out of the three tested shows even a higher mean consumption of T. urticae than that recorded for Neoseiulus californicus and N. cucumeris. It is attracted by food source and is able to walk along the tomato stem. These results are encouraging enough to consider T. (A.) recki as a good natural enemy candidate for biological control (especially based on biodiversity conservation). Further experiments should be developed to test the predatory ability of this species at larger scale (entire tomato plants and tomato fields or greenhouses)., Acarologia, 60, 684-697

Trichome-mediated defence in wild and cultivated tomato cultivars has been extensively studied against some mite species for several decades. Previous studies have shown that this mechanism negatively affects phytophagous mites and their predators. To better explain the tritrophic relationship of tomatoes, the interactions between population densities of the tomato rust mite, Aculops lycopersici (Massee) (Acari: Eriophyidae), and its predators on the tomato cultivars, namely, Dora, Etna, Grande, H2274, Jana and M1103, and the trichome densities of these cultivars were investigated in both a climatic room and an organic tomato field from 2014-2015. Under both controlled and field conditions, the A. lycopersici population density was significantly higher in the stake tomato cultivars, Jana and Etna, than in other tomato cultivars. When the tomato rust mite’s population density was the highest during mid-August and mid-September in the tomato field, the population density of the predator species, Tydeus kochi Oudemans (Tydeidae), showed a similar population pattern and significant positive correlation with the A. lycopersici density. However, density of this predator mite was significantly lower than that of A. lycopersici over the entire season. Remarkably, the glandular trichome type VI density was significantly higher in the stake cultivars than other cultivars. In contrast, significantly fewer glandular trichomes were found in the indeterminate tomato cultivars, Grande and H2274, which had fewer tomato rust mites and larger tydeid mite predator densities. These results support the hypothesis that trichomes provide excellent shelter for tomato rust mites and are obstacles for its predator mites. However, the population density of the insect predator, Macrolophus sp., was not affected by the trichome density or tomato cultivar, but its population density was not significantly correlated with that of the A. lycopersici population.

Mites of family Stigmaeidae are potential predators of various species of phytophagous mites through the world.The present study was conducted in Acarology Research Laboratory Plant Protection Research Institute, Dokki, Egypt. The aim of this work was to study the effect of different prey species on the biology of stigmaeid mite, Agistemus vulgaris Soliman and Gomaa. The results showed that A.vulgaris completed its life cycle in 12.56 days when fed on Tetranychus urticae Koch as compared to 12.09 and 10.75 days when fed on Oligonychus sayedi Zaher, Gomaa & El-Enany and Aculops lycopersici Massee, respectively. The maximum average fecundity (53.75 eggs/female) was recorded after feeding on O. sayedi where as after feeding on T. urticae and A. lycopersici , it was 28.43 and 21.93, respectively. Predatory mite has better life table parameters in comparison with the other prey mites. The biological aspects of the predator was as follow, Mean generation time (T) averaged 18.63, 19.18 and 15.34 days, respectively; Net reproductive rate (Ro) averaged 12.82, 24.38 and 9.81; intrinsic rate of natural increase (rm) was 0.13, 0.16 and 0.14; finite rate of increase (λ) averaged 1.14, 1.18 and 1.16 when the mite fed on immature stages of T. urticae, O. sayedi and A. lycopersici, respectively. A. vulgaris is considered a promising biological control agent against phytophagous mites.

This study is conducted to develop a new method of early occurrence monitoring for Aculops lycopersici Massee (Acari: Eriophyidae), a major pest in tomato. A. lycopersici causes damage to plants such as curling of leaflet edges, followed by leaflet bronzing. As feeding continues by the mites, the plant takes on a russeted, wilted appearance, eventually culminating in leaflet desiccation and finally plant death. Fruit damages in tomato were shown when the density of mites was very high. Also, A. lycopersici caused more damage to unripe fruits than ripe fruits. The time taken to detect A. lycopersici on green label sticker was 7.0 seconds, the shortest. Blue, orange and white label stickers took 17.1, 19.8 and 12.3 seconds respectively. The permeable microscope with side illumination was useful in observing A. lycopersici on label stickers. A. lycopersici began to occur in late-April and the density of the mites increased rapidly after mid-May. The density peaked in mid to late-June, and decreased after late-June. A. lycopersici was observed on lower stems 20 days after the release of mites and observed on higher stems 60 days after. The peaked densities were observed on stems 40 and 60 days after and on leaf 80 days after. The label sticker is enough to monitor early occurrence of A. lycopersici in tomato cultivation facilities.

Experiments were conducted at Faculty of Agriculture farm Shebin Elkom and laboratory of Economic Entomology and Agricultural Zoology Department to study the eriophyid mites associated with three vegetable plants, five fruit trees, and two ornamental plants during the period from 2013/2015. Incidence studies indicated that 11 species of eriophyid mites belonging to 7 Genera was collected. Five plant extracts were chosen to determine their effect on Aculops lycopersici mite, after one week the redaction percentages were the highest when cayenne pepper and garlic used 98, 91 % while this percentage approximately ranged between 85, 88 % for other plant extracts, three weeks after application the reduction percentages were 100% in all plant extracts treatment except thyme record 98%. Ten chemical compounds as pesticides were experimented to show their effect on Aculops lycopersici. One day after application Sino S recorded the highest reeducation percentage 97% followed by Citrogard and Dumber 90%, while the lowest reduction percentages ware recorded by Vermex and Arrow 43, 46 %. Also, studied effect of some control methods against eriophyid mites on some morphological characters of tomato plants. It was observed that plant length increase in all treatments than untreated plants, increase percentage were 88.6, 89.7 % for Acari stop and high point treatment, while it was 88.4 , 90.9% in Cayenne pepper and Garlic three weeks after application. Biology of eriophyid mite Aceria dioscoridis reared in laboratory under 28± 2 C and 75± 5% R. H. the mean of incubation period was 1.75± 0.32 days, 72% from eggs was hatched to active larvae. Some biological aspects of predatory mite were studies when used Aceria dioscoridis ,Cisabroptus Kenyaeas prey, the incubation period of predator egg was 2.44± 0.61days for female, while it was 2.42± 0.51days for male. The life cycle of the predatory mite ranged from 8:12 days for female and 7: 12 for male.

Development, oviposition, and survival of a commercially available predatory mite, Amblyseius swirskii (Athias-Henriot), were investigated to determine the life history parameters when they consumed a diet of cattail ( Typha latifolia L.) pollen or tomato russet mites ( Aculops lycopersici [Massee]) at 25 ± 0.5 °C and 70 ± 10% RH. Both diets were favorable for development, oviposition, and survival of A. swirskii . Amblyseius swirskii reared on mite prey showed improved performance as compared to pollen. Females laid a total of 26.8 and 38.1 eggs on the pollen and mite diets, respectively. The mortality of female A. swirskii was very low during the first 20 days on both diets, and the cumulative Weibull models that were used to describe age-specific survival and fecundity of female showed a good fit to the data. The net reproductive rate ( R 0 ), intrinsic rate of increase ( r m ), and finite rate of increase ( λ ) of A. swirskii were higher on russet mites than when fed on the pollen diet due to their shorter immature development period and higher oviposition rate. The intrinsic rate of increase ( r m ) of the predatory mite was 0.185 and 0.201 on the pollen and mite diet, respectively. The mean generation time ( T ) and the population doubling time ( D t ) were not significantly different for A. swirskii on the two diets. Our results provide life history information for a commercially available A. swirskii using two favorable diets and can be used to compare population growth under other diet sources.

Predation, development, and oviposition experiments were conducted to evaluate Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) as a potential biological control agent for tomato russet mite, Aculops lycopersici (Massee) (Acari: Eriophyidae), which can be a serious pest of greenhouse tomatoes. Results showed that A, swirskii attacked all developmental stages of A. lycopersici and had a type II functional response at the prey densities tested. The attack rate and handling time estimates from the random predator equation were 0.1289/h and 0.2320 h, respectively, indicating that A. swirskii can consume 103.4 individuals per day. Predation rates of A. swirskii on A. lycopersici in the presence of alternative food sources such as pollen, first-instar thrips, or whitefly eggs were 74, 56, and 76%, respectively, compared with the predation rate on A. lycopersici alone. A. swirskii successfully completed their life cycle on either A. lycopersici or cattail (Typha latifolia L.) pollen. At 25°C and 70% RH, developmental time of female A. swirskii fed on A. lycopersici or on cattail pollen was 4.97 and 6.16 d, respectively, For the first 10 d after molting to the adult stage, A. swirskii fed on A. lycopersici had higher daily oviposition rate (2.0 eggs per day) than on pollen (1.5 eggs per day). From this laboratory study, it can be concluded that A. swirskii has promising traits as a predator against A. lycopersici and that their populations can be maintained using alternative food sources such as cattail pollen. We suggest that the effectiveness of A. swirskii against A. lycopersici under field conditions needs next to be investigated.

Thirty-seven accessions from six species belonging to the genus Lycopersicon were tested for susceptibility to the tomato russet mite, Aculops lycopersici. Significant differences in damage index, but not in mite density, were found among cultivars of tomato, L. esculentum var. esculentum; the damage index of Hawaii 7996 was significantly lower than that of Jupiri and Ponderoza, and the damage index of Yellow-Piko was lower than that of Jupiri. When compared among species, mite densities and damage indices of wild Lycopersicon species were significantly lower than those of tomato cultivars. In particular, mite densities on 82000F of L. pennellii and PI127827 of L. hirsutum were very low (

Developmental rates of Aculops lycopersici increased linearly as rearing temperature increased. A total of 81.2 degree-days above a developmental zero of 10.5°C were required to complete development from egg to adult emergence. Adult longevity decreased with increasing temperature. The highest intrinsic rate of natural increase was observed at 25°C as 0.253 per day. The population increased exponentially on greenhouse tomato plants and the intrinsic rate of natural increase was estimated to be 0.175 per day. A. lycopersici first reproduced on the released leaves then moved upward. The infestation caused great injury to the plants, with a large number of leaves turning brown and then drying up. The number of leaves, the plant height and the diameter of the main stem of the plants all decreased. Homeopronenmtus anconai naturally occurred on tomato plants. After the rapid population increase of H. anconai, the A. lycopersici population decreased sharply. An adult H. anconai consumed an average of 69.3 A. lycopersici deutonymphs per day in the laboratory. H. anconai was thought to be a prospective natural enemy of A. lycopersici.

The distribution pattern of Aculops lycopersici (Massee) in a tomato leaf and method for estimating the density of the mite were examined. The distribution pattern of adults and nymphs was similar. About a half number of mite population infested leaflets and the other half petioles. Most of the mites infested the upper surface of the leaves. On petioles, the density of the mite was high at the posterior part. Mite numbers were large on leaflets near the stem. The percentage of the number of mite population on each part of the leaflet to the total number on whole leaf did not vary irrespective of the population density. On leaflets, the mite density was higher in the middle than periphery and also higher at the bottom than the top. However, the density became uniform in the leaflet when the density became high. From the distribution data obtained, a method for estimating the densities of mite population on whole leaf was proposed, i.e. mite numbers on the second and third leaflets and several parts of the petiole were counted.

The biology of the Australian phytoseiid mite Typhlodromips montdorensis is described from material collected in Queensland and South Australia in 1994-1996. At 25 ° C, when fed on cumbungi ( Typha sp.) pollen, the life cycle was completed in approximately 7 days, with an intrinsic rate of natural increase ( r m ) of 0.32. Female-male pairs produced a mean total of 52.7 eggs within 28 days of oviposition. Females that were deprived of males after first mating stopped laying eggs after 7-19 days; however, if another male was added, they resumed egg laying and produced, on average, a total of 49.4 eggs. The sex ratio was 2.24 females to one male. At 25 ° C, fecundity on a diet of thrips larvae (first-instar Frankliniella schultzei Trybom) was high, ranging from 2.72 to 3.58 eggs per day on the third day, depending on previous diet. Consumption rate of thrips was also high, with an average of 7.23-14.44 first-instar larvae eaten per day on the third day, depending again on previous diet and also on number of thrips larvae made available. The species was also observed to feed on: (i) broad mite, Polyphagotarsonemus latus (Banks); (ii) tomato russet mite, Aculops lycopersici (Massee); and (iii) two-spotted mite, Tetranychus urticae Koch. No diapause was observed under conditions of 25 ° C, 8 h light and 10 ° C, 16 h dark. Eggs were sensitive to low humidity, with 50% failing to hatch below 70.8% relative humidity. This species is of interest as a candidate biological control agent for thrips, broad mite and tomato russet mite in protected crops.

The biology of the Australian phytoseiid mite Typhlodromalus lailae is described from material collected in Western Australia and New South Wales in 1994. At 25°C, when fed on cumbungi (Typha sp.) pollen, the life cycle is completed in approximately 6 days, with an intrinsic rate of natural increase (rm), of 0.38. Female−male pairs produced a mean total of 44.6 eggs within 22 days of oviposition, with 39% of these females living in excess of 29 days. Females that were deprived of males after first mating stopped laying eggs after 4−9 days, but if another male was added they resumed egg laying and produced close to a full complement of eggs (mean 42 eggs). At 25°C, fecundity on a diet of cumbungi pollen or thrips larvae (first-instar Frankliniella schutzei Trybom) was high, averaging 3.71 and 3.33 eggs per day, respectively, over a 3-day period. The sex ratio was approximately 1.5 females to 1 male. Consumption rate of thrips was also high, with an average of approximately seven first-instar or two second-instar F. schultzei larvae eaten per day. The species was also observed to feed on broad mite, Polyphagotarsonemus latus (Banks), and tomato russet mite, Aculops lycopersici (Massee). No diapause was observed under conditions of 25°C 8 h light and 10°C 16 h dark. Eggs were sensitive to low humidity, with 50% failing to hatch below 71.1% relative humidity. This species is of interest as a candidate biological control agent for thrips, broad mite and tomato russet mite in protected crops.

The effect of constant temperature on the development, reproduction and population growth of Aculops lycopersici reared on a tomato leaflet was investigated. Survival rates from egg to adult were more than 69% at temperatures between 15°C and 27.5°C, but only 53% at 30°C. Developmental rates increased linearly as rearing temperature increased from 15°C to 27.5°C. A total of 81.2 degree-days above a developmental zero of 10.5°C were required to complete development from egg to adult emergence. Adult longevity decreased with increasing temperature. Fecundity was highest at 25°C with 51.7 eggs per female. The highest intrinsic rate of natural increase was observed at 25°C as 0.253 per day.

The population growth of the tomato russet mite, Aculops lycopersici (Massee), and its effect on tomato plants were studied in glasshouses. The population increased exponentially for six weeks after infestation. The intrinsic rate of natural increase was estimated to be 0.175 per day. At seven weeks after infestation, the predator, Homeopronematus anconai (Baker) (Acari: Tydeidae), appeared on several plants. The population of A. lycopersici decreased rapidly on plants where the predator appeared, due to predation. But it decreased gradually on plants where the predator did not appear, because of the damage to the host plant caused by the mites. More than 70% of the population infested the leaves. A. lycopersici first reproduced on the released leaves then moved upward. The infestation caused great injury to the plants, with a large number of leaves turning brown and then drying up. The number of leaves, the plant height and the diameter of the main stem of the plants all decreased.

The effect of different levels of NPK on the infestation of Aculops lycopersici (Massee) (Acari: Eriophyidae) on tomato (Lycopersicon esculentum Mill), cultivar IPA 5, under field conditions was studied. The experimental design of randomized blocks with a factorial arrangement was used, including four blocks and utilizing four levels of N (0, 60, 120, and 180 kg/ha), three levels of P (0, 80, and 160 kg/ha), and two levels of K (0 and 120 kg/ha). The active forms of A. lycopersici were sampled weekly, 53 to 113 days after the tomato plants were sowed. Twenty five leaflets were collected from the intermediate part of the plants and an area of 1,76 cm2 of the under side of these leaflets with bigger colonies was examined. The plants fertilized with 120 kg/ha of K were more infested by A. lycopersici. There was a direct relationship between mite infestation and the levels of P applied to the soil; At a K level of 120 kg/ha the infestation increased with P levels. At N levels of 60 and 180 kg/ha the infestation increased, whereas at 120 kg/ha it was reduced. However the NP interaction presented a low effect on the infestation at higher levels of N. The levels of N and P applied to the soil were positive and significantly correlated to the content found in the tomato leaves. No significat correlation was observed with regard to K.

Predation experiments were conducted to identify a predator with the capacity to control the tomato russet mite, Aculops lycopersici (Massee) (Eriophyidae), in greenhouse tomato crops. The efficiency of four predatory mites species was evaluated at the individual level in the laboratory: the tydeid Homeopronematus anconai (Baker) and the phytoseiids Phytoseiulus persimilis Athias-Henriot, Amblyseius cucumeris Oudemans, and A. fallacis Garman. The first three species had already been suggested as potential control agents. Predation by P. persimilis was essentially zero on tomato russet mite, whereas H. homeopronematus failed to develop to the adult stage when fed solely with this prey. Amblyseius cucumeris developed successfully on tomato russet mite but failed to reproduce. Only A. fallacis appears to possess several of the biological attributes required to control the tomato russet mite. This species attacks all stages of the pest and displays excellent survival (.92%), adequate rate of development (6.3 days at 22 °C), and good reproductive capacity in the presence of A. lycopersici.

The nature of the damage caused by eriophyoid mites and the assessment of yield losses still require detailed studies if appropriate control and risk mitigation strategies are to be planned. The economic importance of eriophyoid mites is increasing worldwide and a lot of species have reached a permanent pest status in certain crops, while others represent a quarantine threat for several countries. Due to their relevant role in Europe and elsewhere, three eriophyoid mites that have been frequently reported in recent research, are here considered as case studies: two of them (the apple rust mite, Aculus schlechtendali, and the grape rust mite, Calepitrimerus vitis) colonise temperate fruits, while one (the tomato russet mite, Aculops lycopersici) affects vegetables. The damage assessment related to the apple rust mite has been evaluated on different apple varieties with implications for pest control. Some factors affecting the spread and economic importance of the grape rust mite have been identified. The complexity and difficulty in controlling the tomato russet mite by chemicals enhances the interest in biological control agents. Considerations on interactions between eriophyoids and host plants (e.g. resistance, varietal susceptibility), on pest management regimes (e.g. impact of fungicides, resistance to acaricides, perspectives on biological control) are presented.

Growing of vegetables and ornamentals in the open or as protected crops all the year round is a factor responsible for changes in the biology and ecology of some insects and mites, which can be summarized as follows: (1) the life cycle closes and development occurs all the year round; (2) pests adapt and new strains and populations appear (anholocyclic forms of Aphis naslurtii on capsicum; (3) northwards movement of distribution limits (Peridroma saucia, Chrysodeixis chalcites, Aculops lycopersici, Polyphagotarsonemus latus, Empoasca decipiens); (4)indifferent organisms become pests (Udea ferrugalis). From this point of view, the idea of a new pest must be given a wider interpretation. Details are given on P. latus, E. decipiens, U. ferrugalis and C. chalcites and their control. The following treatments are suitable for IPM programmes: seedling treatment with the systemic insecticide oxamyl, spraying with Thiozol 80 (a.i. 80% wettable sulphur) and Morestan (a.i. 25% quinomethionate) against P. latus; use of light traps and electric killers against Lepidoptera and spraying with Lepidocide (Bacillus thuringzensis) against caterpillars.

The area of protected crops in Hungary is about 5300 ha. Most of it is under plastic, the area under glass being only about 250 ha. Vegetable growing makes up 80%, mostly on private farms. The main crops are capsicum, tomato and cucumber. On relatively small areas, ornamentals, principally cut flowers, are produced: carnation, gerbera, rose and chrysanthemum. The three most important, commonly occurring pests are Trialeurodes vaporariorum, Tetranychus urticae and aphids (Aphis gossypii, Myzus persicae, A. nasturtii). Polyphagotarsonemus latus, Liriomyza trifolii and Aculops lycopersici caused considerable economic damage during the eighties. However, in the last few years these pests have not been observed in any crops. Two new glasshouse pests have been described from ornamentals during the last 2 years in Hungary: Frankliniella occidentalis and Bemisia tabaci. Their accidental appearance in vegetable crops could lead to direct economic loss, besides endangering biological control systems.

There were significant differences in the level of susceptibility among the 12 varieties which were screened for resistance to A. lycopersici Pronounced tolerance to leaf damage was recorded on varieties Early Stone Improved and Beauty. Oxheart and Bonny Best both of which had comparatively lower mite densities were highly susceptible. Flower bud formation was not significantly affected by the mite damage. However, the number of dead flowers and flower buds on infested plants was significantly more than on protected ones. Russetting of young fruits due to mite damage differed significantly among the varieties tested, and was positively correlated with moisture content of young fruits. The least and most affected varieties were Beauty and Red Cloud respectively. The percentage yield loss was highest on Hybrid Beefmaster and Oxheart and lowest on Roma and Money Maker.

The objective of this study was to determine effects of total rainfall, mean temperature, predators, height of canopy, levels of nitrogen and potassium in leaves, and the density of leaf trichomes on the attack intensity of Tetranychus evansi and T. urticae (Acari: Tetranychidae) and Aculops lycopersici (Acari: Eriophyidae) in five plantations of the eggplant Solanum melongena var. ‘Natu Nobilis’ in two regions of Brazil. Higher numbers of individuals of A. lycopersici, T. evansi and T. urticae/cm2 were observed on eggplants in the Municipality of Guidoval than in Vicosa which might be explained by the fact that Guidoval showed hotter and more rainy weather. A. lycopersici was positively correlated with mean temperature (r = 0.54, P = 0.03), and T. evansi was positively correlated with total rainfall (r = 0.54; P = 0.04), while for T. urticae the correlation with total rainfall was almost significant (r = 0.47, P = 0.055). No significant effects were found (P > 0.05) of natural enemies, levels of N and K and leaf trichome density on population densities of mites. A. lycopersici showed higher density on the apical leaves while nymphs and adults of T. evansi and eggs of T. urticae had higher numbers on leaves of the apical and medium parts of eggplants than on the lower leaves. Nymphs and adults of T. urticae showed higher attack intensity on leaves from the medium and lower thirds of the plants.

The pests and their natural enemies were surveyed in 1991–1992 in Izmir Province of the Aegean Regin of Turkey1,2. The major pests were determined as: whiteflies (Trialeurodes vaporariorum Westw., Bemisia tabaci Gern.) on tomato; aphid (Aphis gossypii Glover) and spider mite (Tetranychus cinnabarinus Boiss.) on cucumber; spidermite (T. urticea Koch.) and aphids (A. gossypii and Myzus persicae Sulzer) on pepper. It were found that the pests populations couldn’t be suppressed in spite of heavy wide spectrum pesticides treatments. The secondary pests were determined as; Aculops lycopersici (Massee) on tomato; Thrips tabaci Lindeman, whitefllies, leafminers on cucumber and pepper. It were recorded that the secondary pests were suppressed by the heavy treatments against the major pests.

The biology of Typhlodromips swirskii (Athias-Henriot), Typhlodromus athiasae Porath and Swirski and Paraseiulus talbii (Athias-Henriot) was studied using Aculops lycopersici (Massee) active stages as food source. For T. swirskii, development was faster and reproduction was higher than in T. athiasae. Survival of immatures of P. talbii was low on A. lycopersici and all failed to develop to adulthood. A total of 35.4 and 30.3 eggs per female, respectively, were obtained when T. swirskii and T. athiasae were fed on active stages of the tomato rust mite. A diet of A. lycopersici provided the shortest female longevity and highest mean total fecundity, which resulted in the highest net reproductive rate (Ro = 26.785), intrinsic rate of natural increase (rm = 0.235) and finite rate of increase (A = 1.265) for T. swirskii. The mean generation time ranged between 13.97 and 17.85 days for T. swirskii and T. athiasae, respectively.

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.

Population parameters of the tydeid mite Homeopronematus anconai (Baker) utilizing various food materials were determined. Mite densities increased rapidly when fed cattail pollen provided on a grape leaf substrate. On pollen in the absence of the leaf substrate, the population first declined and then slowly increased. Fungal spores were a poor food source, with or without leaf tissue. On grape leaf alone, mite numbers failed to increase. After 20 d of exposure to tomato russet mites (TRM), Aculops lycopersici (Massee), plus pollen, pollen alone, TRM alone, and with no food, H. anconai adult females had 39, 19, 10, and 0% survival, respectively, and the cumulative number of eggs per female was 8.1, 6.8, 1.5, and 0, respectively. Significantly more TRM were consumed per female H. anconai in the absence of pollen, which suggests pollen is of high nutritive value.

The predacious miteAgistemus exsertus Gonzalez was reared in the laboratory on the eriophyid miteAculops lycopersici (Massee) for studying the development, fecundity and predation efficiency.