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Somnath Roy - One of the best experts on this subject based on the ideXlab platform.
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detection and biochemical characterization of acaricide resistance in field populations of tea red spider mite Oligonychus coffeae acari tetranychidae in assam tea plantation of india
International Journal of Acarology, 2019Co-Authors: Somnath RoyAbstract:ABSTRACTThe red spider mite, Oligonychus coffeae, (RSM) is one of the most damaging pests of tea in most tea-producing countries. The use of synthetic acaricide, the main strategy for controlling R...
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geographical variation in susceptibility of tea red spider mite Oligonychus coffeae nietner acari tetranychidae to commonly used acaricides in tea plantations of assam north east india
International Journal of Acarology, 2018Co-Authors: Somnath Roy, Gautam Handique, Anjali Km Prasad, Bipanchi Deka, Krandashree Duarah, Archita Barua, Bithika Phukan, Azizur RahmanAbstract:The tea red spider mite, Oligonychus coffeae, is one of the most destructive pests of tea in the world which is mainly managed by chemical acaricides. In the present study, concentration-mortality ...
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clove oil efficacy on the red spider mite Oligonychus coffeae nietner acari tetranychidae infesting tea plants
Proceedings of the Zoological Society, 2017Co-Authors: Archita Barua, Somnath Roy, Gautam Handique, Azizur Rahman, Foridur Rahman Bora, Dwiban Pujari, Narayanannair MuraleedharanAbstract:The tea red spider mite, Oligonychus coffeae Nietner (Tetranychidae), is an economically important pest of agricultural and ornamental crops and considered one of the major pests of tea plants in North-east India. In view of increasing resistance recorded in insect and mite pests against pesticides, a study was conducted to determine the acaricidal, antiovipositional, repellent and ovicidal activities of clove oil (an essential oil from the clove plant, Syzygium aromaticum L. Merr. & Perry: Myrtaceae) against tea-red-spider-mite. Mortality of O. coffeae varied with the concentrations and the duration of exposure time of the mites after application of oil. Rate of deposition of eggs by mites on treated leaf surfaces as well as the viability rate of eggs decreased significantly. In addition, certain concentrations of clove oil have been proved effective against adult mites.
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terminalia chebula retz combretaceae source of a botanical acaricide against Oligonychus coffeae nietner acarina tetranychidae
International Journal of Acarology, 2014Co-Authors: Somnath Roy, Azizur Rahman, Ajit Kumar Phukan, Narayanannair MuraleedharanAbstract:Aqueous extract of the dry pericarp of the fruits of Terminalia chebula was evaluated in the laboratory against the tea red spider mite, Oligonychus coffeae (Nietner) to determine its effect on mortality of adult mites, viability of eggs and oviposition deterrence. The same extract was also evaluated in the field to determine its effect on mite populations. A direct spray method was used in the laboratory at concentrations of 1%, 2%, 3%, 4%, 5%, and 6%. Mortality of O. coffeae was dependent on both concentration and time after application. Deposition of eggs by adult mites on treated leaf surfaces decreased significantly and the viability of eggs was also significantly reduced. No phytotoxic effect was observed when tea bushes were sprayed with different doses of aqueous extract of the dry pericarp of the fruits of Terminalia chebula. Tea samples were taint free. Quality (appearance of liquor, flavour, taint, and taste) of tea was not adversely affected by treatment with the extract. With the easy availab...
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bioefficacy assessment of melia azedarach l seed extract on tea red spider mite Oligonychus coffeae nietner acari tetranychidae
International Journal of Acarology, 2012Co-Authors: Somnath Roy, Ananda MukhopadhyayAbstract:Aqueous seed extract of Melia azedarach (L.) was evaluated against tea red spider mite, Oligonychus coffeae (Nietner), in relation to mortality of adult mites, viability of eggs and subsequent adult emergence and oviposition deterrence in the laboratory, and the extract underwent field evaluation in terms of per cent reduction of the mite population. Direct spray methods were used in the laboratory with concentrations of 1%, 2%, 4%, 6%, 8% and 10%. Mortality of O. coffeae was dependent on both concentration and time (56.4% mortality on the first day; 95.6% mortality by the seventh day). The viability of eggs was reduced significantly compared with untreated mite's eggs. Significant reduction in adult emergence and increased duration of total developmental period were noted. Deposition of eggs by adult mites on treated leaf surface was decreased significantly compared with the control. No phytotoxic effect (score 0–5% and grade 1) was observed in the field when tea bushes were sprayed with different doses ...
Azariah Babu - One of the best experts on this subject based on the ideXlab platform.
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Diagnoses and re-description of Coccinellid beetles, Stethorus rani Kapur and Stethorus aptus Kapur (Coleoptera: Coccinellidae) preying on tea red spider mite Oligonychus coffeae Nietner (Acari: Tetranychidae)
International Journal of Tropical Insect Science, 2020Co-Authors: Azariah Babu, J. Poorani, Vattakandy Jasin Rahman, Shaloo Ayri, Amsalingam Roobakkumar, V. V. RamamurthyAbstract:Stethorus aptus Kapur and Stethorus rani Kapur are two important predatory ladybird beetles preying on red spider mite, Oligonychus coffeae Nietner infesting tea in South India. This study re-describes these two predatory beetles since it was found that the original descriptions were scanty. In this study, an attempt has been made on the diagnoses with a detailed description which is supplemented with current terminology, illustrations, coloured images, morphometrics and SEM images of both species. The morphometrics done in the study deals with the length and width of the egg, larvae, pupa and adult of both male and female. Body colour, setae, clypeus, eyes, antennae, scutellum, elytron, abdomen, legs and genitalia were re-described. The present study of the surface morphology with SEM puts forward the differences observed in the size of the punctures on pronotum of two species and the proportion of elytral length versus width as additional diagnostic characters of significance.
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Seasonal Abundance and Predatory Potential of Stethorus aptus Kapur (Coleoptera: Coccinellidae): A Biocontrol Agent of Tea Red Spider Mite Oligonychus coffeae Nietner (Acarina: Tetranychidae)
Proceedings of the Zoological Society, 2018Co-Authors: Archita Barua, Azariah Babu, Ratul Ch RajkhowaAbstract:The tea red spider mite, Oligonychus coffeae Nietner is one of the major pests of tea plants in North-east India. The ladybird beetle, Stethorus aptus Kapur, is a newly reported predator of O. coffeae . Predatory efficiency study of S. aptus under laboratory conditions revealed that adult of S. aptus consumed significantly more mites than larvae. In free choice condition, the predator consumed within a range of 48–56 adults and 82–90 larvae of O. coffeae whereas the 3rd and 4th instar larvae of S. aptus consumed 20–26 adults and 50–60 larvae of O. coffeae per day respectively. Population dynamics of S. aptus was observed for 1 year under field conditions. The maximum density of the predator was recorded during January to March and it gradually declined from September onwards. Population of S. aptus showed positive correlation with its prey O. coffeae and relative humidity while effect of other factors was insignificant.
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evaluation of certain leaf extracts against red spider mite Oligonychus coffeae nietner acarina tetranychidae infesting tea
International Journal of Acarology, 2012Co-Authors: Duraikannu Vasanthakumar, Amsalingam Roobakkumar, Mariappan S R Subramaniam, Pandian Kumar, Chandran Sundaravadivelan, Azariah BabuAbstract:Leaf extracts of some common plants such as Vitex negundo (Linn. & Paracetamol), Gliricidia maculata (HBK), Wedelia chinensis (Osbeck), Morinda tinctoria (Roxb) and Pongamia glabra (Vent) were evaluated for their acaricidal activity against the red spider mite, Oligonychus coffeae, in the laboratory using the leaf disc method under controlled conditions. Leaves collected from the above mentioned plants were shade-dried followed by oven drying (at 60°C) and were milled in an electric blender. After this, the powder was taken for the preparation of the concentrations required for the various bioassays. Aqueous extracts were prepared and their effects on the mortality of adults and eggs and as oviposition deterrents were assessed after spraying and were compared with an untreated control. All tested plant extracts showed varying levels of effect on red spider mite compared with the untreated control. Among them, the aqueous extracts of M. tinctoria and P. glabra had maximum ovicidal action, ovipositional det...
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functional and numerical responses of the predatory mite neoseiulus longispinosus to the red spider mite Oligonychus coffeae infesting tea
Journal of Insect Science, 2012Co-Authors: Vattakandy Jasin Rahman, Azariah Babu, Amsalingam Roobakkumar, Kandasamy PerumalsamyAbstract:Functional and numerical responses of the predatory mite, Neoseiulus longispinosus (Evans) (Acari: Phytoseiidae) to the red spider mite, Oligonychus coffeae Nietner (Acari: Tetranychidae), infesting tea were determined in a laboratory on leaf discs. Prey consumption increased with increases in temperature and prey density. Handling time decreased and successful attack rate increased with increased temperature. N. longispinosus was more voracious on larvae and nymphs than on adults of O. coffeae. Handling time was higher on adult females than on larvae. Rate of predation leveled off at temperatures greater than 25° C. Functional responses to prey density at six temperatures and to each life stage of O. coffeae approximated the Holling type II model. The oviposition rate increased with prey consumption and temperature. On average, a predator consumed 1.62 adult female prey for every egg it laid. With a fixed number of prey available, predation rate per predator decreased with increased predator density.
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pseudomonas fluorescens as an efficient entomopathogen against Oligonychus coffeae nietner acari tetranychidae infesting tea
Journal of Entomology and Nematology, 2011Co-Authors: Amsalingam Roobakkumar, Azariah Babu, Duraikkannu Vasantha Kumar, Soumik SarkarAbstract:The biocontrol efficacy of the bacterium, Pseudomonas fluorescens was evaluated against the red spider mite (RSM), Oligonychus coffeae in the laboratory. Both bacterial suspension and extra cellular filtrate of 24, 48 and 72 h old were sprayed to test the efficacy of bacterium against adult mites. The mortality due to P. fluorescens increased as the age and percentage of culture increased. Chitinase activity of P. fluorescens in response to chitin induction was measured in nutrient agar by estimating the amount of reducing sugars liberated. Chitinase activity was higher in 72 h old culture.
Tetsuo Gotoh - One of the best experts on this subject based on the ideXlab platform.
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a new species of spider mite Oligonychus neocastaneae sp nov acari tetranychidae from japan
Zootaxa, 2018Co-Authors: Tea Arabuli, Tetsuo GotohAbstract:A new species Oligonychus neocastaneae sp. nov. is described and illustrated from Castanea crenata Sieb. et Zucc. (Fagaceae). The new species closely resembles Oligonychus castaneae Ehara Gotoh, 2007, which inhabits the same host plant, Castanea crenata, but mainly differs by the aedeagus in having a longer distal portion which forms a small sigmoid and acuminate tip, instead of having a shorter distal portion which ends in a truncate tip. Several differences were also observed between the two species in the leg setal counts of tarsus II in the male and female; the number of tactile setae and solenidia (in parentheses) was 11(1) for the female and male in the new species, but in O. castaneae this count is 12(1) for the female and 12(2) for the male. A maximum likelihood tree based on the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA (mtDNA) showed that O. neocastaneae sp. nov. was clearly separated from O. castaneae and other related species. A key to all species of the genus Oligonychus known in Japan is given.
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molecular based identification and phylogeny of Oligonychus species acari tetranychidae
Journal of Economic Entomology, 2012Co-Authors: Tomoko Matsuda, Norihide Hinomoto, R N Singh, Tetsuo GotohAbstract:The genus Oligonychus has been morphologically divided into two groups based on the direction of curvature of the aedeagus and includes some morphologically similar species that are difficult to distinguish. To develop DNA-based methods for identifying Oligonychus species and to determine the phylogenetic relationships among them, we examined the cytochrome c oxidase subunit I gene of mitochondrial DNA and the internal transcribed spacer and 28S regions of nuclear ribosomal RNA gene for 17 species. Based on the genetic distances (p-distances) of the three DNA regions, the range of intraspecific divergence was found to be below (and not overlap) the range of interspecific divergence, which allowed the 17 species to be discriminated correctly, consistent with their classification based on morphology. Phylogenetic trees constructed by neighbor-joining and Bayesian methods clearly showed two clades, consisting of species whose aedeagi curve ventrally and dorsally, respectively. Three Oligonychus species inhabiting gramineous plants formed clearly defined subclades.
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Divergence in host range and reproductive compatibility in three strains of Oligonychus gotohi Ehara (Acari: Tetranychidae)
International Journal of Acarology, 2007Co-Authors: Tetsuo Gotoh, Yasuki Kitashima, Satoshi Abe, Shozo EharaAbstract:Abstract Preliminary observations indicated that Oligonychus gotohi Ehara collected from deciduous chestnut (deciduous-tree strain) could not develop on leaves of the evergreen broad-leaved tree Lithocarpus edulis (Makino) Nakai in the laboratory. Furthermore, we found an evergreen arrhenotokous (A) strain that produces both female and male progeny and an evergreen thelytokous (T) strain that produces only female progeny. These observations suggest that O. gotohi consists of either host races or sibling species. To determine which is the case, we examined the above three strains on 19 fagaceous plant species. The deciduous-tree strain successfully developed and oviposited on seven deciduous trees but did not develop on evergreen trees at all. The evergreen-A strain had the narrowest host range and could develop and oviposit only on three species of deciduous trees and only on three species of evergreen trees. The evergreen-T strain grew well on six deciduous trees and on all but one of the evergreen trees...
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wolbachia distribution and cytoplasmic incompatibility based on a survey of 42 spider mite species acari tetranychidae in japan
Heredity, 2003Co-Authors: Tetsuo Gotoh, H Noda, Xiaoyue HongAbstract:Wolbachia are a group of maternally inherited bacteria that infect a wide range of arthropods. Wolbachia infections are known to result in the expression of various abnormal reproductive phenotypes, the best known being cytoplasmic incompatibility. The first systematic survey of 42 spider mite species in Japan revealed that seven species (16.7%) were infected with Wolbachia. Wolbachia in the spider mites were grouped into three subgroups in supergroup B by phylogenetic analyses of the wsp gene. Most spider mites did not show cytoplasmic incompatibility when infected males were crossed with uninfected females. However, all infected populations of Panonychus mori and Oligonychus gotohi (five and four populations, respectively) possessed modification-positive strains of Wolbachia, and the cytoplasmic incompatibility decreased egg hatchability and female ratio of the spider mites. Thus, some Wolbachia strains cause sex ratio distortion in their hosts.
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susceptibility of the red spider mite Oligonychus coffeae acari tetranychidae to acaricides on tea plants in japan
International Journal of Acarology, 2001Co-Authors: Tetsuo Gotoh, Yasuki Kitashima, K Goka, T NagataAbstract:Abstract The red spider mite, Oligonychus coffeae (Nietner) (Tetranychidae), was recently found on mango and tea plants in the Ryukyu Islands, southern Japan. The susceptibility of adult females and eggs of a population from tea on Okinawa Island to 19 acaricides was examined, using a spray tower. The LC50 values in female adults of O. coffeae indicated high susceptibility to 15 acaricides and resistance only to chlorfenapyr. Of the group of 15 chemicals, bifenazate and fenbutatiaoxide yielded higher LC50 values in O. coffeae than in the susceptible strain of T. kanzawai, suggesting that these chemicals may be less effective in controlling O. coffeae. Eggs were resistant to ten acaricides, especially to bifenthrin and chlorfenapyr, but susceptible to the other nine. Thus, eggs were more resistant to the chemicals than adult females, but nine acaricides are candidates for effective control of O. coffeae.
Jin Dao-chao - One of the best experts on this subject based on the ideXlab platform.
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FIGURE 15 in Ontogenetic development and redescription of Oligonychus pratensis (Banks, 1912) (Acari: Tetranychidae)
2018Co-Authors: Li Juan, Yi Tian-ci, Guo Jian-jun, Jin Dao-chaoAbstract:FIGURE 15. Oligonychus pratensis, larva, venter. Scale bar 100 µm
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Ontogenetic development and redescription of Oligonychus pratensis (Banks, 1912) (Acari: Tetranychidae)
2018Co-Authors: Li Juan, Yi Tian-ci, Guo Jian-jun, Jin Dao-chaoAbstract:Li, Juan, Yi, Tian-Ci, Guo, Jian-Jun, Jin, Dao-Chao (2018): Ontogenetic development and redescription of Oligonychus pratensis (Banks, 1912) (Acari: Tetranychidae). Zootaxa 4486 (3): 349-375, DOI: https://doi.org/10.11646/zootaxa.4486.3.
Daochao Jin - One of the best experts on this subject based on the ideXlab platform.
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redescription of three species of Oligonychus acari tetranychidae from china
Systematic & Applied Acarology, 2019Co-Authors: Jianjun Guo, Daochao JinAbstract:Two species of Oligonychus are redescribed: O. baipisongis Ma & Yuan, 1976 and O. chamaecyparisae Ma & Yuan, 1976. Moreover, O. hainanensis Ma, Yuan & Lin, 1979 is here recognized as a junior synonym of O. biharensis (Hirst, 1924), which is also redescribed here based on adult females, males and deutonymphs. The redescription of O. baipisongis is based on holotype and paratypes, the types of O. chamaecyparisae could not be located but the species is described from male and female material collected by En-Pei Ma in 1978 from Lanzhou City, Xi-An City and Xining City. The dorsal setae in O. baipisongis show remarkable sexual dimorphism. The difference between the aedeagi of O. chamaecyparisae and Oligonychus perditus Pritchard & Baker, 1955 are discussed. All three species are diagnosed, illustrated with line drawings and photographs.
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ontogenetic development and redescription of Oligonychus pratensis banks 1912 acari tetranychidae
Zootaxa, 2018Co-Authors: Jianjun Guo, Daochao JinAbstract:Oligonychus pratensis (Banks, 1912) is redescribed based on adult females as well as immature instars collected from Imperata (Poaceae) in Zhangjiajie City, Hunan Province, China. The ontogenetic development of chaetotaxy in O. pratensis is the same as that in O. afrasiaticus (McGregor, 1939) and O. saccharinus Baker & Pritchard, 1960. Moreover, we remove O. shinkajii Ehara, 1963 from synonymy with O. modestus (Banks, 1900), due to significant differences in their aedeagal morphology.
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ontogenetic development and redescription of Oligonychus metasequoiae acari tetranychidae
Systematic & Applied Acarology, 2017Co-Authors: Daochao JinAbstract:Abstract Oligonychus metasequoiae Kuang, 1992 is redescribed based on the larva, protonymph, deutonymph and adult male and female specimens from China. The ontogenetic development of chaetotaxy in O. metasequoiae and the number and position of solenidia on tibia I are discussed. Patterns of setal addition on legs I–IV from larvae to adults in this species are different from the basic pattern of the Tetranychinae outlined by Lindquist.
