Euseius Ovalis Research Articles

Identification of Euseius nicholsi and Euseius oolong (Acari: Phytoseiidae) by using integrative taxonomy

Several specimens of an Euseius sp. were collected from Bajiaozhai National Forest Park (Guilin, China). Preliminary morphological observations showed that the species is very similar to Euseius nicholsi (Ehara and Lee, 1971) which is frequently reported from China and other far eastern countries, as well as Euseius oolong Liao and Ho, 2018, a species recently described from Taiwan. However, some morphological differences such as the body size, reticulation on the dorsal plate, shape of calyx of spermatheca etc., existed between these two species. In order to ascertain whether these morphological differences are representing different or a single species belonging to the genus Euseius, molecular analyses were conducted by using ITS, 12S rDNA, and mitochondrial DNA COI markers. Results revealed very low levels of genetic divergence (ITS 0–1%, 12S rDNA 0–2.37%, COI 0–2%), based on the three molecular markers, between Euseius sp., Euseius nicholsi [collected from Institute of Zoology, Guangdong Academy of Sciences (IZGAS) and from National Center for Biotechnology Information (NCBI) data], and Euseius oolong (collected from IZGAS). In addition, the phylogenetic tree constructed by using the neighbor-joining method also showed that sequences of these three populations were clustered in a single clade and parallel to out-group Euseius ovalis. Therefore, it can be concluded that Euseius sp. probably belongs to Euseius nicholsi, and Euseius oolong is a junior synonym of this species. This study clearly demonstrates the importance of integrative taxonomy for the proper identification of phytoseiid mites, one of the most important groups of predators utilized for biological control all over the world.

Phytoseiidae on Citrus in Florida Dooryard, Varietal, and Commercial Trees between 1951 and 2014, and Species Recommendations for Evaluation in Citrus Under Protective Screen (CUPS)

A survey of the mite fauna on citrus was conducted in 550 dooryard trees including 25 varietal trees in Florida, USA, during 2009 to 2014 in the following counties: Broward, Charlotte, Collier, Dade, Indian River, Lee, Manatee, Martin, Palm Beach, Pinellas, Polk, St. Lucie, and Sarasota. One abandoned block of trees was sampled in Highlands County. Seventeen species of Phytoseiidae were identified from 1,982 slide-mounted mites collected from these trees. Euseius ennsi Ueckermann, Moraes & Childers, Euseius ovalis (Evans), Neoseiulus loxus (Schuster & Pritchard), Phytoseius coheni Swirski & Shechter, Typhlodromalus jucundus (Chant), and Typhlodromina johnsoni (Mahr) were new records on Florida citrus. Amblyseius largoensis (Muma) was the most abundant species with 854 of the phytoseiids followed by E. ovalis, Euseius mesembrinus (Dean), E. ennsi, and Iphiseioides quadripilis (Banks) (all Mesostigmata: Phytoseiidae) with 418, 388, 81, and 68 mites, respectively. Amblyseius largoensis was the most frequently collected phytoseiid from 220 of the 550 dooryard and varietal trees, followed by E. ovalis from 97 trees. A total of 787 commercial citrus trees were sampled in Florida from 2009 to 2014 in De Soto, Hardee, Hendry, Highlands, Indian River, Okeechobee, Palm Beach, Polk, and St Lucie counties. One T. jucundus was collected from these trees. Amblyseius largoensis and E. ovalis are recommended for evaluation as general predators of mite and insect pests in enclosed structures of citrus under protective screen (CUPS). Both mites have broad host ranges and are known mite predators, including some insect pests. Both species appear to have some degree of pesticide tolerance and use supplemental plant pollens such as Quercus virginiana Mill. (Fagaceae) or Typha spp. L. (Poaceae). Differences in phytoseiid species in this study and from earlier sampling for mites on citrus in Florida from 1986 to 2003 by the first author, a horticultural mineral oil (HMO) field study during 1994 to 1996, M. H. Muma from 1951 to 1975, and Denmark and Evans (2011) are included for comparison. A combined total of 60 phytoseiid species are reported on Florida citrus for the period of 1951 to 2014.

Diversity of mite fauna associated with agro-horticultural crops in Bihar, India

A total of twenty species of predatory mite belonging to thirteen genera like Amblyseius, Euseius, Typhlodromips, Scapulaseius, Neoseiulus, Phytoseius, Typhlodromus, Lasioseius and Agistemus were recorded. The predatory mite, Amblyseius largoensis was found as most predominant species occupied 43.41% of total population followed by Typhlodromips syzygii, Lasioseius parberlesei, Typhlodromus (Anthoseius) spp., Phytoseius jujuba and Neoseiulus longispinosus enumerated 16.48, 6.43, 5.95, 4.68 and 4.19% of total predatory mite population in surveyed areas, respectively. Some other predatory mites belonging to the families like Tydeidae, Bdellidae, Ascidae, Cunaxidae, Stigmaeidae and Cheyletidae under the order Prostigmata were also recorded during the period of investigation. Moreover, six major phytophagous mite viz., Tetranychus urticae, Eutetranychus orientalis, Oligonychus litchi, Oligonychus mangiferous and Schizotetranychus baltazari belonging to the family Tetranychidae and Polyphagotarsonemus latus under the family Tarsonemidae were documented and considered as key mite pest. The predatory mites were found effective against phytophagous mites and other soft bodied insect pests. However, Amblyseius largoensis, Amblyseius brachycalyx, Euseius ovalis, Euseius alstoniae, Euseius sajnekhalicus, Typhlodromips syzygii, Neoseiulus longispinosus, Neoseiulus imbricatus, Scapulaseius moraesi, Phytoseius jujuba, Typhlodromus (Anthoseius) sp., Lasioseius parberlesei, Agistemus industani, Tydeus spp., Bdelloides spp. and Cunaxa spp. were found preying on Tetranychus urticae, Eutetranychus orientalis, Schizotetranychus baltazari, Oligonychus litchi, Oligonychus mangiferous, Polyphagotarsonemus latus, Brevipalpus phoenicis, Eriophyidae, mealy bug and pupae of whitefly.

Survey of phytoseiid mites (Acari: Mesostigmata, Phytoseiidae) in citrus orchards and a key for Amblyseiinae in Vietnam

Citrus is the second largest fruit crop in Vietnam. Phytoseiid mites are important natural enemies of mite pests and small insects in citrus orchards. By examining the specimens collected from three citrus orchards in the Mekong Delta in the south of Vietnam, a new record of phytoseiid mite Amblyseius obtuserellus Wainstein and Begljarov, 1971 was found and two other species Amblyseius largoensis (Muma, 1955) and Euseius ovalis (Evans, 1953) were also obtained. Herein, they are re-described and illustrated based on the current specimens. A key for Amblyseiinae in Vietnam is also provided

New records of Phytoseiidae (Acari: Mesostigmata) from Mauritius

Mauritius is one of the three islands constituting Mascareignes Archipelago, with La Réunion and Rodrigues. So far, onIy three mite species of the family Phytoseiidae are known from Mauritius, namely Amblyseius caudatus, Euseius ovalis and Phytoseius coheni. We report in this paper the results of a brief survey recently conducted on Mauritius Island, in which four additional species were found, namely Paraphytoseius orientalis, Phytoseiulus persimilis, Scapulaseius reptans and Typhlodromips culmulus.

Biological control of Echinothrips americanus by phytoseiid predatory mites and the effect of pollen as supplemental food

The poinsettia thrips, Echinothrips americanus Morgan, is an upcoming pest in greenhouse crops, causing serious damage in various vegetable and ornamental crops through extensive foliage feeding. We assessed which stages of E. americanus are attacked and killed by the phytoseiid predatory mites Amblyseius swirskii (Athias-Henriot), Amblydromalus limonicus (Garman and McGregor), Euseius gallicus Kreiter and Tixier and Euseius ovalis (Evans). Both the predation and oviposition rates were assessed in the laboratory to evaluate which mite species is potentially the most effective predator of E. americanus. In two greenhouse trials with non-flowering sweet pepper plants, we compared the efficacy of the predators E. gallicus and E. ovalis with A. swirskii and we assessed how this was affected by the application of cattail pollen. All stages of E. americanus, except adults, were consumed by all species of predatory mites. The highest predation and oviposition rates were recorded for A. limonicus followed by A. swirskii and E. ovalis when first and second larval stages were provided as prey, but E. ovalis appeared to be the best predator of thrips pupae. Euseius gallicus displayed very low predation and oviposition rates compared to the other species of predatory mites. Cattail pollen did not support the population growth of poinsettia thrips, but it strongly increased the predatory mite population densities, particularly those of E. ovalis. Both A. swirskii and E. ovalis significantly reduced thrips densities on plants. The application of pollen significantly enhanced the control of E. americanus by A. swirskii; this was not the case for E. ovalis. Euseius gallicus did not reduce densities of E. americanus on sweet pepper plants, not even at high densities in the presence of pollen.

The most Common Predators of Bemisia tabaci (Genn.): Biology, Predation, Preferences, Releases, Alternative Food Resources, Combined Use, Current Efforts and Future Perspectives

The cotton whitefly, Bemisia tabaci (Genn.) (Hom.:Aleyrodidae) is a serious pest of greenhouses, horticulture and field crops, and ornamentals worldwide. B. tabaci has been spreading into new territories and causing extensive damage for almost a century and continues to be a severe pest worldwide. However, resistance to insecticides has rendered chemical control ineffective for the management of B. tabaci . Thus, biological control serves as an alternative and has great potential for use against B. tabaci . Biological control of B. tabaci has been used since more than 40 years, and many attempts have ended with complete success. Biological control of B. tabaci by predators represents a key strategy whose potential has gone largely unrealized in many cropping systems. While a great deal of information is available concerning parasitoids of B. tabaci , much less is known about potential of predators as bio-agents. Concomitantly, this paper reviews predators' biology, predation, preferences and releases. In addition, combined use of predators and parasitoids, intraguild predation, alternative food resources and omnivory of predators were discussed. In addition, the paper presents the efforts in biological control of B. tabaci using selected predators, and highlights research gaps and directions deserving further development to create a better understanding of these predators on different crops to control B. tabaci . In spite of hundreds of predators attacking B. tabaci , this review is restricted to the most common predators namely; beetles ( Serangium parcesetosum, Delphastus catalinae and Nephaspis oculatus ), bugs ( Orius laevigatus, Macrolophus caliginosus and Nesidiocoris tenuis ), lacewings ( Chrysoperla carnea and C. pallens ), and mites ( Amblyseius swirskii and Euseius ovalis ). In conclusion, based on information presented herein it appears that predators might be best suited for inclusion in multiple species biological control program for B. tabaci . It is hoped that this paper will help in better understanding of types of future studies necessary for implementing successful biological control programs.

<p><strong>Predatory mite fauna associated with agri-horticultural crops and weeds from the Gangetic Plains ofWest Begal, India*</strong></p>

Astudy was conducted in 2008–2009 to explore the predatory mite fauna from different agri-horticultural crops and weeds in the Gangetic plains ofWest Bengal. A total of 31 species belonging to nine genera, seven families and two orders were identified; they are listed along with their prey, period of occurrence and the plant habitats in which they were recorded. The most frequently collected specieswere the phytoseiids Amblyseius largoensis (Muma) and Neoseiulus longispinosus (Evans), the stigmaeids Agistemus spp. and the anystidWalzia indiana Smith-Meyer&Ueckermann.Given the frequencywithwhich these mites were found, they can be considered potentially useful in suppressing the associated prey mites. The phytoseiids Paraphytoseius multidentatus Swirski & Schechter, Euseius ovalis (Evans), Euseius coccineae (Gupta), Neoseiulus fallacis (Garman) and the cheyletid Cheletogenes ornatus (Canestrini&Fanzago) were less frequently found and less abundant, implying that their impact on prey population is less important. The remaining species were rare.

Predation rates of Neoseiulus womersleyi (Schicha) and Euseius ovalis (Evans) feeding on tetranychid mites (Acari: Phytoseiidae, Tetranychidae)

Predation rates of Neoseiulus womersleyi and Euseius ovalis feeding on eggs, larvae, or protonymphs of Tetranychus urticae, Tetranychus kanzawai, or Oligonychus mangiferus were measured in a chamber at 25 °C. N. womersleyi immatures consumed 9.73 T. urticae eggs, 13.53 larvae, or 11.57 protonymphs, while gravid females consumed 12.13 T. urticae eggs, 14.37 larvae, or 12.07 protonymphs daily. Female N. womersleyi consumed a total of 218.12 T. urticae eggs, 260.85 larvae, or 222.33 protonymphs, while male N. womersleyi consumed a total of 96.39 T. urticae eggs, 112.23 larvae, or 99.65 protonymphs. When O. mangiferus larvae or protonymphs were offered to E. ovalis, immatures consumed 18.57 larvae or 17.47 protonymphs. Gravid females consumed 16.83 larvae or 12.83 protonymphs daily, with a total of 330.68 larvae or 252 protonymphs. Adult E. ovalis males consumed fewer O. mangiferus larvae (107.69) or protonymphs (91.51) than females. Conversion rate of predation to reproduce was expressed as “Food–reproduction exchange rate” of N. womersleyi was lower on T. urticae than on T. kanzawai. E. ovalis showed a higher food–reproduction exchange rate on O. mangiferus than on T. urticae. The results suggest that N. womersleyi and E. ovalis feed mainly on larvae and protonymphs rather than on the eggs of T. urticae, T. kanzawai, and O. mangiferus. We recommended using T. urticae eggs are suitable food for mass rearing for both N. womersleyi and E. ovalis.

The puzzle of DNA sequences of Phytoseiidae (Acari:Mesostigmata) in the public GenBank database

The public database GenBank is an increasingly important source of sequence data for diagnostic and phylogenetic research; however, not all deposited sequences are necessarily correctly ascribed to a source species. We considered the example of the mite family Phytoseiidae to determine how the corresponding sequences could be accurately exploited. Phytoseiidae mites are well known worldwide for their ability to control certain mite and insect pests. The number of molecular approaches, especially for diagnostic purposes, has increased over the past decade, leading to an increase in the number of sequences registered in the GenBank database. The aim of the present paper was to evaluate the validity of the DNA sequences presently assigned to Phytoseiidae species in this database. Three hundred and fifty-one sequences, corresponding to the four most frequently registered DNA fragments (ITS, COI, Cytb and 12S rRNA), were considered. DNA extraction, amplification and sequencing were performed for the fragments 12S rRNA and ITS for Amblyseius andersoni, A. swirskii, Iphiseius degenerans, Euseius ovalis, E. stipulatus, Neoseiulus cucumeris and Typhlodromus pyri, as some identifications were questionable. Numerous problems were evident based on genetic distance analyses of these sequences. First, nomenclatural problems were encountered, preventing the correct identification of the taxa sequenced in one case. Suspected misidentifications were frequent, stressing the importance of voucher specimen availability. For the 12S rRNA fragment, sequences assigned to three Phytoseiidae species were those of their prey (Astigmata), underlining the care that must be taken when manipulating the DNA of such predators (sterile conditions and specific PCR primers). Finally, sequences of two regions of the COI mtDNA were encountered, leading to alignment problems between sequences of a same gene and same species. These results are discussed in relation to responsibilities of authors in terms of taxon identification and the great utility of open access DNA sequence databases, such as GenBank, for improving taxonomic identifications and advancing scientific research.

Development of Neoseiulus womersleyi (Schicha) and Euseius ovalis (Evans) feeding on four tetranychid mites (Acari: Phytoseiidae, Tetranychidae) and pollen

The development of the predatory mites, Neoseiulus womersleyi (Schicha) and Euseius ovalis (Evans), feeding on four tetranychid mites ( Tetranychus urticae, Tetranychus kanzawai, Oligonychus mangiferus, Panonychus citri), maize pollen or Chinese loofah pollen was studied at 25 °C. Immature stages of N. womersleyi feeding on T. urticae and T. kanzawai had shorter developmental duration (4.71 and 5.02 days for females, 4.77 and 5.19 days for males, respectively) than those feeding on other food sources. Immature stages of E. ovalis females feeding on O. mangiferus and T. urticae developed in 4.99 and 5.13 days, respectively, the shortest developmental duration measured. Immature stages of E. ovalis males feeding on O. mangiferus and T. urticae developed in 5.12 and 5.37 days, respectively. The longevity of N. womersleyi males (13.31 to 14.51 days) and females (17.67 to 21.81 days) feeding on T. urticae, T. kanzawai or maize pollen was longer than the longevity of N. womersleyi feeding on O. mangiferus, P. citri or loofah pollen. E. ovalis males (12.91 to 16.74 days) and females (16.24 to 23.77 days) feeding on O. mangiferus, T. urticae or maize pollen lived longer than E. ovalis males and females feeding on T. kanzawai, P. citri or loofah pollen.

Biological control of thrips and whiteflies by a shared predator: Two pests are better than one

We studied the capacity of one species of predator to control two major pests of greenhouse crops, Western flower thrips ( Frankliniella occidentalis (Pergande)) and the greenhouse whitefly ( Trialeurodes vaporariorum (Westwood)). In such a one-predator–two-prey system, indirect interactions can occur between the two pest species, such as apparent competition and apparent mutualism. Whereas apparent competition is desired because it brings pest levels down, apparent mutualism is not, because it does the opposite. Because apparent competition and apparent mutualism occurs at different time scales, it is important to investigate the effects of a shared natural enemy on biological control on a time scale relevant for crop growth. We evaluated the control efficacy of the predatory mites Amblyseius swirskii (Athias-Henriot) and Euseius ovalis (Evans) in cucumber crops in greenhouse compartments with only thrips, only whiteflies or both herbivorous insects together. Each of the two predators controlled thrips, but A. swirskii reduced thrips densities the most. There was no effect of the presence of whiteflies on thrips densities. Whitefly control by each of the two predators in absence of thrips was not sufficient, yet better with E. ovalis. However, whitefly densities in presence of thrips were reduced dramatically, especially by A. swirskii. The densities of predators were up to 15 times higher in presence of both pests than in the single-pest treatments. Laboratory experiments with A. swirskii suggest that this is due to a higher juvenile survival and developmental rate on a mixed diet. Hence, better control may be achieved not only because of apparent competition, but also through a positive effect of mixed diets on predator population growth. This latter phenomenon deserves more attention in experimental and theoretical work on biological control and apparent competition.

PREDATORY MITES FOR BIOCONTROL OF THE GREENHOUSE WHITEFLY, TRIALEURODES VAPORARIORUM IN CUT ROSES

Integrated Pest Management (IPM) is successfully used on a year-round scale on only 15% of the area of roses under glass. Obstacles for further expansion of IPM practices among rose growers are the control of the spidermite Tetranychus urticae and the greenhouse whitefly Trialeurodes vaporariorum. The research stations of Naaldwijk, Aalsmeer and Boskoop have started initiatives in order to enlarge the choice of predator species available for Dutch growers. A series of greenhouse experiments were conducted to select phytoseiid mites suitable for commercial cut roses. Among ten species tested in experimental greenhouses, Euseius ovalis was found to be the most promising control agent of T. vaporariorum. Its efficacy against other pests and its compatibility with chemicals are the subject of further studies. Since E. ovalis is an exotic species formerly not commercially available, efforts are being made to obtain authorization for experimenting with this species in commercial greenhouses in the framework of new fauna protection regulations in The Netherlands.

Evaluation of phytoseiid predators for control of western flower thrips on greenhouse cucumber

Ten predatory mite species, all phytoseiids, were evaluated for control of western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), on greenhouse cucumber. This study was done to further improve biological control of thrips on this crop. Neoseiulus cucumeris (Oudemans) is at present used for biological control of thrips in greenhouses. Compared to this species, Typhlodromalus limonicus (Garman & McGregor), Typhlodromips swirskii (Athias-Henriot) and Euseius ovalis (Evans) reached much higher population levels resulting in a significantly better control of thrips. T. limonicus was clearly the best predator of WFT. Also Euseius scutalis (Athias-Henriot) increased to higher populations levels than N. cucumeris, but without controlling the thrips, probably because of an unequal distribution of this predator on the plant. Iphiseius degenerans (Berlese), Neoseiulus barkeri (Hughes), Euseius finlandicus (Oudemans) and Typhlodromus pyri (Scheuten) did not establish better than N. cucumeris. A non-diapausing exotic strain of N. cucumeris did not differ from the North European strain. The best performers in this study were all of sub-tropical origin. T. limonicus, T. swirskii and E. ovalis have good potentials for controlling not only thrips but also whiteflies. Factors affecting the efficacy of phytoseiids on greenhouse cucumbers are discussed.

A collection of phytoseiid mites (Acari: Phytoseiidae) from Java with description of a new species

Eight species of the mite family Phytoseiidae are reported from West Java, Indonesia. Indoseiulus santosoi sp. nov. is described and figured from a fabaceous climbing plant at Cianjur. Euseius ovalis (Evans), Paraphytoseius seychellensis Schicha & Corpuz-Raros, Indoseiulus armellae (Schicha & Gutierrez), and Phytoseius (Dubininellus) rachelae Swirski & Shechter are recorded for the first time in Java. Redescriptions are given of I. armellae and a previously recorded species, Flagroseius euflagellatus (Karg).