Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.f...Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.farinae)and Dermalophagoides pteronyssinus(D.pteronyssinus).Methods:Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations(50.00%,25.00%,12.50%,6.25%and 3.13%)and exposure times(24hrs,48hrs,72hrs and 96 hrs).All treatments were replicated 7 times,and the experiment repeated once.The topical and contact activities of the two herbs were investigated.Results:Mortalities from lemongrass extract were higher than neem for both topical and contact activities.At 50%concentration,both 24 hrs topical and contact exposures to lemongrass resulted in more than 91%mortalities for both species of inites.At the same concentration and exposure time,neem resulted in topical mortalities of 40.3%and 15.7%against D.pteronyssinus and D.farinae respectively;contact mortalities were 8.0%and 8.9%against the 2 mites,respectively.There was no difference in topical mortalities of D.pteronyssinus from exposure to concentrations oflemongrass and neem up to 12.50%;lemongrass was more effective than neem at the higher concentrations.Conclusions:Generally,topical mortalities of D.farinae due to lemongrass are higher than that due to neem.Contact mortalities of lemongrass are always higher that neem against both species of mites.展开更多
Palynological investigation of the Denwa Formation exposed along Denwa river succession at Saptadara picnic point near village Jhirpa, Satpura Basin, Madhya Pradesh, has revealed the presence of spore-pollen, fungal r...Palynological investigation of the Denwa Formation exposed along Denwa river succession at Saptadara picnic point near village Jhirpa, Satpura Basin, Madhya Pradesh, has revealed the presence of spore-pollen, fungal remains and Oribatid mites. Here, the mites are on record for the first time. Presence of fungal remains strongly depicts the prevalence of a very humid climate with high temperature and rainfall in the region. Poor occurrence of spore-pollen restricts the age determination of the studied section;hence, its age assessment is relative. Thus, an over-view of spore-pollen along with dinocysts and insects reported earlier from the subsurface strata comprising Denwa Formation, from other two localities in the nearby area of village Anhoni, is dealt herein, and that had inferred an age—range from Carnian to Rhaetic for the palynoflora and fauna.展开更多
Water mites (Hydrachnidia) are common external parasites of the medically important mosquitoes (Culicidae). Between April 2014 and April 2015, 64 mites from three genus, Arrenurus 71.9%, Limnochares 3.1%, and Hydrachn...Water mites (Hydrachnidia) are common external parasites of the medically important mosquitoes (Culicidae). Between April 2014 and April 2015, 64 mites from three genus, Arrenurus 71.9%, Limnochares 3.1%, and Hydrachna 25.0%, were collected from female mosquitoes in two rural locations near Cuiabá, Mato Grosso, Brazil. Dipterous species parasitized by water mites belonging to seven species: Anopheles (Nys.) darling, An. evansae, Aedes (Och.) scapularis, Ae. serratus, Mansonia (Man.) wilsoni, Psorophora (Jan.) ferox, Ps. varipes. The most common specimens to accommodate the water mites were Anopheles (Nys.) darlingi and Psorophora (Jan.) varipes. The prevalence of parasitism of mosquitoes by water mites found in this study was less than 5. However, few studies have addressed the ecological role of mites and their biotopes, as well as host-parasite interactions in Brazil.展开更多
Water mites (Hydrachnidia) are common external parasites of the medically important mosquitoes (Culicidae). Between April 2014 and April 2015, 64 mites from three genus, <i>Arrenurus</i> 71.9%, <i>Li...Water mites (Hydrachnidia) are common external parasites of the medically important mosquitoes (Culicidae). Between April 2014 and April 2015, 64 mites from three genus, <i>Arrenurus</i> 71.9%, <i>Limnochares</i> 3.1%, and <i>Hydrachna</i> 25.0%, were collected from female mosquitoes in two rural locations near Cuiabá, Mato Grosso, Brazil. Dipterous species parasitized by water mites belonging to seven species: <i>Anopheles</i> (<i>Nys.</i>)<em> darling</em>, <i>An. evansae, Aedes</i> (<i>Och.</i>) <em>scapularis, Ae. serratus</em><em>, Mansonia</em> (<em>Man</em>.) <em>wilsoni, Psorophora</em> (<em>Jan.</em>) <em>ferox, Ps.</em><em> varipes</em>. The most common specimens to accommodate the water mites were <i>Anopheles </i>(<i>Nys.</i>) <em>darlingi</em> and <em>Psorophora</em> (<i>Jan.</i>) <em>varipes</em>. The prevalence of parasitism of mosquitoes by water mites found in this study was less than 5. However, few studies have addressed the ecological role of mites and their biotopes, as well as host-parasite interactions in Brazil.展开更多
Objective:To investigate the short and long tenn efficacy of a commercial air ionizer in killing Dermatophagoides pteronyssinus(D.pteronyssinus)and Dermalophagoides farinae(D.farinae)mites.Methods:The effect of a comm...Objective:To investigate the short and long tenn efficacy of a commercial air ionizer in killing Dermatophagoides pteronyssinus(D.pteronyssinus)and Dermalophagoides farinae(D.farinae)mites.Methods:The effect of a commercial ionizer on D.pteronyssinus and D.farinae was evaluated in the laboratory,using a specially designed test.Mortality was assessed after 6,16and 24 hours for direct exposure and after 24,36,48,60 and 72 hours for exposure in simulated mattress.New batches of mites were used for each exposure time.Results:LT_(50)for direct exposure of ionizer was 10 hours for D.pteronyssinus and 18 hours for D.farinae.The LT_(50)for exposure in simulated mattress was 132 hours or 5.5 days for D.pteronyssinus and 72 hours or 3days for D.farinae.LT_(95)for direct exposure of ionizer was 36 hours for D.pteronyssinus and D.farinae.Meanwhile,the LT_(95)for exposure in simulated mattress was 956 hours or 39.8 days for D.pteronyssinus and 403 hours or 16.8 days for D.farinae.Conclusions:This study demonstrates the increasing mite mortalities with increasing exposure time of a commercial ionizer and suggests that negative ions produced by an ionizer kill dust mites and can be used to reduce natural mile populations on exposed surfaces such as floors,clothes,curtains,etc.However,there is reduced efficacy on mites inside stuffed materials as in mattresses and furniture.展开更多
This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also kno...This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also known as two-spotted spider mite, is a harmful plant-feeding pest that causes damage to over 300 species of plants. Its predator, Phytoseiulus persimilis, a mite in the Family Phytoseiidae, effectively controls spider mite populations. In this study, we compared four mathematical models using a numerical simulation. These models include two known models: self-diffusion, and cross-diffusion, and two new models: chemotaxis effect model, and integro diffusion model, all with a Beddington-De Angelis functional response. The modeling results were validated by fitting experimental data. Results demonstrate that interaction scheme plays an important role in the prey-predator system and that the cross-diffusion model fits the real system best. The main contribution of this paper is in the two new models developed, as well as the validation of all the models using experimental data.展开更多
This study evaluated the allergen impermeability against airborne allergens of dust mite droppings through all parts of commercial bed covers, including surface seams and zippers. Specimens were taken from places with...This study evaluated the allergen impermeability against airborne allergens of dust mite droppings through all parts of commercial bed covers, including surface seams and zippers. Specimens were taken from places with and without seams and zipper. A novel penetration cell was developed to expose the specimens to an inoculum of purified mite droppings that was assessed for its allergen content Der p1 prior to the penetration tests. Using covers of different construction and material, the penetration level increased significantly in the presence of seams and zippers and could reach up to 6% depending on the seam’s/zipper’s characteristics and quality. Therefore, zippers and seams have to be considered as access points for the penetration of mite droppings. As for the penetration of airborne mite particles through the zipper, the penetration level was greatly attenuated by the presence of a cover strip. Depending on the respective quality and the construction type, the mite allergen Der p1 penetrated most likely through the zipper and seams of the specimens, already after a single laundry cycle. Hence, laundry may compromise the barrier performance and proves to be an important quality feature. In all samples, the textile surface showed sufficient allergen impermeability. Our conclusions provide recommendations to both manufacturers and users.展开更多
In this study the distribution and relationships of element levels in water and water mite species (Acari, Hydrachnidia) selected as model organisms have been examined in two different lakes. Water samples from Eber a...In this study the distribution and relationships of element levels in water and water mite species (Acari, Hydrachnidia) selected as model organisms have been examined in two different lakes. Water samples from Eber and Karamik Lakes were analyzed with ICP (ICP-OES Instrument Spectro Genesis Fee, Germany) equipment to determine the element levels in the water. That impact level of these elements on the distribution of species was discussed. Change in the lake water composition was not a significantly determining factor in the number of species and diversities of water mites. However, eutrophication was observed to be a determining factor on the distribution of species.展开更多
Ras opposite(Rop)is known to play an essential role in regulating vesicle trafficking,including synaptic transmission and general secretion.The fundamental roles of Rop have been confirmed by the observation that null...Ras opposite(Rop)is known to play an essential role in regulating vesicle trafficking,including synaptic transmission and general secretion.The fundamental roles of Rop have been confirmed by the observation that null mutations in many organisms generate lethal phenotypes during embryogenesis.However,the effects of Rop during the postembryonic stages,especially in non-model organisms,remain largely unknown.Here,we provide new data that enhance our understanding of Rop's roles in the adults of multiple species of Tetranychus spider mites(Acari:Tetranychidae),a class of notorious agricultural pests.Our in silico and experimental evidence demonstrated that Rop is under purifying selection and is highly conserved in Tetranychus spp.RNA interference experiments showed that Rop is required for maintaining normal fecundity but has no significant effect on survival.We further demonstrate that knockdown of Rop darkens the body color of spider mites and blocks the excretion of fecal pellets,which is likely to be related to an abnormality in the excretion of food waste in the digestive system.Overall,our findings clarify novel functions of a vesicle trafficking-related gene in the adult stage of multiple Tetranychus species and highlight the need to evaluate the roles of essential genes in various organisms.展开更多
A new species of Torrenticola(Acari:Hydrachnidia)is reported from China,namely T.(T.)gladiusirostrum Jia,Gu&Guo,sp.nov.And T.(Megapalpis)distans K.O.Viets,1981 is recorded in China for the first time.Both descript...A new species of Torrenticola(Acari:Hydrachnidia)is reported from China,namely T.(T.)gladiusirostrum Jia,Gu&Guo,sp.nov.And T.(Megapalpis)distans K.O.Viets,1981 is recorded in China for the first time.Both descriptions and illustrations of these species are provided.The new species is characteristic by:dorsal plate arrangement 2+1;infracapitular bay U-shaped,deep and wide,V2 almost at same level of Ap;gnathosoma ventral apodeme short and blunt,rostrum flat and sword-shaped;P-2 and P-3 ventral processes smooth and pointed,and P-2 ventral process curved upwards,P-4 with two ventral extensions.展开更多
An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geograph...An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geographical subregions, namely Middle Subregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, Eastern Plateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun- tainous Subregion of Yunnan. The captured 10 803 small mammal hosts belong to nine families, 29 genera and 52 species in four orders (Rodentia, Insectivora, Scandentia and Lagomorpha). A total of 68 571 gamasid mites were collected from the body surface of the captured small mammal hosts and all the gamasid mites were identified to 10 families, 33 genera and 112 species. This paper lists all the mite species, together with their taxonomic position (genera and families) and their corresponding hosts. Much more mite species were found in the Middle Subregion of Hengduan Mountains than in other geographical subregions. The total individuals of mites and small mammals in the Middle Subregion of Hengduan Mountains are also the most plentiful in the five geographical subregions. Three dominant mite species and three dominant small mammal hosts were determined as the dominant species in the investigated areas of Yunnan Province. The dominant hosts are Rattus flavipectus (which accounts for 34.85% of the total individuals), Apodemus chevrieri (13.43%) and Rattus norvegicus (10.40%) while the dominant gamasid mite species are Laelaps nuttalli (Hirst, 1915) (27.84%), Laelaps echidninus (Berlese, 1887) (18.38%) and Laelaps guizhouensis (Gu et Wang, 1981) (14.79%). The results showed the high species diversity of gamasid mites in Yunnan Province and the uneven distribution feature in different subregions.展开更多
文摘Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.farinae)and Dermalophagoides pteronyssinus(D.pteronyssinus).Methods:Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations(50.00%,25.00%,12.50%,6.25%and 3.13%)and exposure times(24hrs,48hrs,72hrs and 96 hrs).All treatments were replicated 7 times,and the experiment repeated once.The topical and contact activities of the two herbs were investigated.Results:Mortalities from lemongrass extract were higher than neem for both topical and contact activities.At 50%concentration,both 24 hrs topical and contact exposures to lemongrass resulted in more than 91%mortalities for both species of inites.At the same concentration and exposure time,neem resulted in topical mortalities of 40.3%and 15.7%against D.pteronyssinus and D.farinae respectively;contact mortalities were 8.0%and 8.9%against the 2 mites,respectively.There was no difference in topical mortalities of D.pteronyssinus from exposure to concentrations oflemongrass and neem up to 12.50%;lemongrass was more effective than neem at the higher concentrations.Conclusions:Generally,topical mortalities of D.farinae due to lemongrass are higher than that due to neem.Contact mortalities of lemongrass are always higher that neem against both species of mites.
文摘Palynological investigation of the Denwa Formation exposed along Denwa river succession at Saptadara picnic point near village Jhirpa, Satpura Basin, Madhya Pradesh, has revealed the presence of spore-pollen, fungal remains and Oribatid mites. Here, the mites are on record for the first time. Presence of fungal remains strongly depicts the prevalence of a very humid climate with high temperature and rainfall in the region. Poor occurrence of spore-pollen restricts the age determination of the studied section;hence, its age assessment is relative. Thus, an over-view of spore-pollen along with dinocysts and insects reported earlier from the subsurface strata comprising Denwa Formation, from other two localities in the nearby area of village Anhoni, is dealt herein, and that had inferred an age—range from Carnian to Rhaetic for the palynoflora and fauna.
文摘Water mites (Hydrachnidia) are common external parasites of the medically important mosquitoes (Culicidae). Between April 2014 and April 2015, 64 mites from three genus, Arrenurus 71.9%, Limnochares 3.1%, and Hydrachna 25.0%, were collected from female mosquitoes in two rural locations near Cuiabá, Mato Grosso, Brazil. Dipterous species parasitized by water mites belonging to seven species: Anopheles (Nys.) darling, An. evansae, Aedes (Och.) scapularis, Ae. serratus, Mansonia (Man.) wilsoni, Psorophora (Jan.) ferox, Ps. varipes. The most common specimens to accommodate the water mites were Anopheles (Nys.) darlingi and Psorophora (Jan.) varipes. The prevalence of parasitism of mosquitoes by water mites found in this study was less than 5. However, few studies have addressed the ecological role of mites and their biotopes, as well as host-parasite interactions in Brazil.
文摘Water mites (Hydrachnidia) are common external parasites of the medically important mosquitoes (Culicidae). Between April 2014 and April 2015, 64 mites from three genus, <i>Arrenurus</i> 71.9%, <i>Limnochares</i> 3.1%, and <i>Hydrachna</i> 25.0%, were collected from female mosquitoes in two rural locations near Cuiabá, Mato Grosso, Brazil. Dipterous species parasitized by water mites belonging to seven species: <i>Anopheles</i> (<i>Nys.</i>)<em> darling</em>, <i>An. evansae, Aedes</i> (<i>Och.</i>) <em>scapularis, Ae. serratus</em><em>, Mansonia</em> (<em>Man</em>.) <em>wilsoni, Psorophora</em> (<em>Jan.</em>) <em>ferox, Ps.</em><em> varipes</em>. The most common specimens to accommodate the water mites were <i>Anopheles </i>(<i>Nys.</i>) <em>darlingi</em> and <em>Psorophora</em> (<i>Jan.</i>) <em>varipes</em>. The prevalence of parasitism of mosquitoes by water mites found in this study was less than 5. However, few studies have addressed the ecological role of mites and their biotopes, as well as host-parasite interactions in Brazil.
文摘Objective:To investigate the short and long tenn efficacy of a commercial air ionizer in killing Dermatophagoides pteronyssinus(D.pteronyssinus)and Dermalophagoides farinae(D.farinae)mites.Methods:The effect of a commercial ionizer on D.pteronyssinus and D.farinae was evaluated in the laboratory,using a specially designed test.Mortality was assessed after 6,16and 24 hours for direct exposure and after 24,36,48,60 and 72 hours for exposure in simulated mattress.New batches of mites were used for each exposure time.Results:LT_(50)for direct exposure of ionizer was 10 hours for D.pteronyssinus and 18 hours for D.farinae.The LT_(50)for exposure in simulated mattress was 132 hours or 5.5 days for D.pteronyssinus and 72 hours or 3days for D.farinae.LT_(95)for direct exposure of ionizer was 36 hours for D.pteronyssinus and D.farinae.Meanwhile,the LT_(95)for exposure in simulated mattress was 956 hours or 39.8 days for D.pteronyssinus and 403 hours or 16.8 days for D.farinae.Conclusions:This study demonstrates the increasing mite mortalities with increasing exposure time of a commercial ionizer and suggests that negative ions produced by an ionizer kill dust mites and can be used to reduce natural mile populations on exposed surfaces such as floors,clothes,curtains,etc.However,there is reduced efficacy on mites inside stuffed materials as in mattresses and furniture.
文摘This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also known as two-spotted spider mite, is a harmful plant-feeding pest that causes damage to over 300 species of plants. Its predator, Phytoseiulus persimilis, a mite in the Family Phytoseiidae, effectively controls spider mite populations. In this study, we compared four mathematical models using a numerical simulation. These models include two known models: self-diffusion, and cross-diffusion, and two new models: chemotaxis effect model, and integro diffusion model, all with a Beddington-De Angelis functional response. The modeling results were validated by fitting experimental data. Results demonstrate that interaction scheme plays an important role in the prey-predator system and that the cross-diffusion model fits the real system best. The main contribution of this paper is in the two new models developed, as well as the validation of all the models using experimental data.
文摘This study evaluated the allergen impermeability against airborne allergens of dust mite droppings through all parts of commercial bed covers, including surface seams and zippers. Specimens were taken from places with and without seams and zipper. A novel penetration cell was developed to expose the specimens to an inoculum of purified mite droppings that was assessed for its allergen content Der p1 prior to the penetration tests. Using covers of different construction and material, the penetration level increased significantly in the presence of seams and zippers and could reach up to 6% depending on the seam’s/zipper’s characteristics and quality. Therefore, zippers and seams have to be considered as access points for the penetration of mite droppings. As for the penetration of airborne mite particles through the zipper, the penetration level was greatly attenuated by the presence of a cover strip. Depending on the respective quality and the construction type, the mite allergen Der p1 penetrated most likely through the zipper and seams of the specimens, already after a single laundry cycle. Hence, laundry may compromise the barrier performance and proves to be an important quality feature. In all samples, the textile surface showed sufficient allergen impermeability. Our conclusions provide recommendations to both manufacturers and users.
文摘In this study the distribution and relationships of element levels in water and water mite species (Acari, Hydrachnidia) selected as model organisms have been examined in two different lakes. Water samples from Eber and Karamik Lakes were analyzed with ICP (ICP-OES Instrument Spectro Genesis Fee, Germany) equipment to determine the element levels in the water. That impact level of these elements on the distribution of species was discussed. Change in the lake water composition was not a significantly determining factor in the number of species and diversities of water mites. However, eutrophication was observed to be a determining factor on the distribution of species.
基金funded by the National Natural Science Foundation of China(No.32020103011,32001905,and 31871976)the Fundamental Research Funds for the Central Universities(No.KJQN202110).
文摘Ras opposite(Rop)is known to play an essential role in regulating vesicle trafficking,including synaptic transmission and general secretion.The fundamental roles of Rop have been confirmed by the observation that null mutations in many organisms generate lethal phenotypes during embryogenesis.However,the effects of Rop during the postembryonic stages,especially in non-model organisms,remain largely unknown.Here,we provide new data that enhance our understanding of Rop's roles in the adults of multiple species of Tetranychus spider mites(Acari:Tetranychidae),a class of notorious agricultural pests.Our in silico and experimental evidence demonstrated that Rop is under purifying selection and is highly conserved in Tetranychus spp.RNA interference experiments showed that Rop is required for maintaining normal fecundity but has no significant effect on survival.We further demonstrate that knockdown of Rop darkens the body color of spider mites and blocks the excretion of fecal pellets,which is likely to be related to an abnormality in the excretion of food waste in the digestive system.Overall,our findings clarify novel functions of a vesicle trafficking-related gene in the adult stage of multiple Tetranychus species and highlight the need to evaluate the roles of essential genes in various organisms.
基金supported by SRT program of Guizhou University((2019)337)National Natural Science Foundation of China(31772421)Guizhou Provincial Science and Technology Projects(Qiankehe Pingtai Rencai-GCC[2022]029-1)。
文摘A new species of Torrenticola(Acari:Hydrachnidia)is reported from China,namely T.(T.)gladiusirostrum Jia,Gu&Guo,sp.nov.And T.(Megapalpis)distans K.O.Viets,1981 is recorded in China for the first time.Both descriptions and illustrations of these species are provided.The new species is characteristic by:dorsal plate arrangement 2+1;infracapitular bay U-shaped,deep and wide,V2 almost at same level of Ap;gnathosoma ventral apodeme short and blunt,rostrum flat and sword-shaped;P-2 and P-3 ventral processes smooth and pointed,and P-2 ventral process curved upwards,P-4 with two ventral extensions.
文摘An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geographical subregions, namely Middle Subregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, Eastern Plateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun- tainous Subregion of Yunnan. The captured 10 803 small mammal hosts belong to nine families, 29 genera and 52 species in four orders (Rodentia, Insectivora, Scandentia and Lagomorpha). A total of 68 571 gamasid mites were collected from the body surface of the captured small mammal hosts and all the gamasid mites were identified to 10 families, 33 genera and 112 species. This paper lists all the mite species, together with their taxonomic position (genera and families) and their corresponding hosts. Much more mite species were found in the Middle Subregion of Hengduan Mountains than in other geographical subregions. The total individuals of mites and small mammals in the Middle Subregion of Hengduan Mountains are also the most plentiful in the five geographical subregions. Three dominant mite species and three dominant small mammal hosts were determined as the dominant species in the investigated areas of Yunnan Province. The dominant hosts are Rattus flavipectus (which accounts for 34.85% of the total individuals), Apodemus chevrieri (13.43%) and Rattus norvegicus (10.40%) while the dominant gamasid mite species are Laelaps nuttalli (Hirst, 1915) (27.84%), Laelaps echidninus (Berlese, 1887) (18.38%) and Laelaps guizhouensis (Gu et Wang, 1981) (14.79%). The results showed the high species diversity of gamasid mites in Yunnan Province and the uneven distribution feature in different subregions.