Eriophyidae Research Articles

Invasion of the gall mite Aceria genistae (Acari: Eriophyidae), a natural enemy of the invasive weed Cytisus scoparius, into California, U.S.A. and predictions for climate suitability in other regions using ecological niche modelling

ABSTRACTScotch broom (Cytisus scoparius (L.) Link) is a European shrub that has naturalised in several countries worldwide and is recognised as an invasive weed in much of western North America. The mite Aceria genistae (Nalepa) is a coevolved, gall-inducing herbivore associated with Scotch broom in its native range and has been intentionally introduced as a classical weed biological control agent of C. scoparius in Australia and New Zealand. An adventive, never intentionally introduced, population of A. genistae was discovered in Washington and Oregon, U.S.A. in 2005. Surveys for A. genistae in California resulted in the discovery of the gall mite in 11 counties, with a widely scattered distribution. Molecular and morphological assessments confirm the mites collected from galls in California are A. genistae. Whether natural or anthropogenic, the estimated rate of long range dispersal for A. genistae from Washington or Oregon to California ranges from 39 to 62 km/yr. Niche model predictions indicate that A. genistae will continue to expand its distribution throughout much of the Scotch broom-invaded lands of California but areas supporting the weed in the Eastern U.S.A. appear less suitable. Modelling evidence also indicates that portions of Chile and Argentina are suitable for colonisation by A. genistae, also suggesting that expansion of the mite is possible in areas of Tasmania, southeastern Australia, and New Zealand where the mite was released. The environmental safety of A. genistae in relation to non-target plants and the influence of herbivory on Scotch broom fitness are discussed.

Evaluation of Floral Cuts on Eriophyid Mite Retention on Knock Out and Multiflora Rose Cuttings

Current eriophyid mite quantification techniques require transportation of the Rosa spp. cuttings to the laboratory. It is thought that the change in xylem hydraulic conductance within the cut cane could trigger the mites to abandon their host, owing to the changes to the microenvironments that these mites are inhabiting. An experiment was conducted to determine the necessity of floral cuts (reducing stem embolisms by an additional cut underwater) for the retention of eriophyid mites during transit. Four groups of plants (rose rosette virus (RRV)-free Knock Out roses, RRV-infected Knock Out roses, RRV-free multiflora roses, and RRV-infected multiflora roses) were evaluated at different time intervals (0.5, 2, 4, 8, 24, 48, 72, and 96 h postharvest) to assess mite populations on each plant (number of mites per gram of tissue). Cut type (floral or dry cut) and rose species were found not to have a significant effect on the number of mites per gram of tissue found, indicating that floral cuts are not needed for accurately estimating eriophyid mite populations. Rose cuttings infected with RRV were found to have an average of 46 times more mites per gram in comparison with RRV-free cuttings.

Eriophyoid Mites Found on Healthy and Rose Rosette Diseased Roses in the United States1

AbstractPhyllocoptes fructiphilus (Keifer), known as the rose bud mite, is an eriophyoid mite that has been shown to be the vector of Rose rosette virus (RRV), an Emaravirus, and the causal agent of rose rosette disease (RRD). Studies were conducted of mites found on roses, using various microscopy techniques including wide field, phase contrast and differential interference contrast light microscopy, and table top and low temperature scanning electron microscopy. Surveys of roses from several states within the US indicate the presence of three species of eriophyid mites: Phyllocoptes fructiphilus, Eriophyes eremus (Druciarek & Lewandowski), and Callyntrotus schlechtendali (Nalepa). Phyllocoptes fructiphilus was found primarily under the petioles (stipules), inside the flower sepals appressed to the ovary/seeds, and on the surface of the leaves. It was collected on plants with or without symptoms of RRD and often hides amongst the dense simple and bulbous, glandular hairs or under the stipules/petioles. Eriophyes eremus was found under the stipules of roses and is now recorded for the first time in the Americas. Callyntrotus schlechtendali was found on the open surface of the older leaves. The latter two species were not observed to be associated with obvious plant injury. In addition, predatory mites were found associated with these mites which may be useful as biological control agents of the eriophyid mites.Index words: insect vectors, disease spread, predatory mites, virusesSpecies used: Rose bud mite [Phyllocoptes fructiphilus (Keifer)]; Roses (Rosa spp.)

Влияние галловых клещей на состояние ассимиляционного аппарата липы сердцевидной

Влияние галловых клещей на состояние ассимиляционного аппарата липы сердцевидной

Resistance to an eriophyid mite in an interspecific hybrid pedigree of Populus.

Schizoempodium mesophyllincola is an eriophyid mite that feeds in leaves of Populus trichocarpa in the central part of this cottonwood tree’s range (i.e., coastal British Columbia, Washington and Oregon) in the Pacific Northwest (PNW) of North America, and on some interspecific hybrids planted in short-rotation, intensive forestry in the region. The mite, a leaf vagrant, sucks the contents of spongy mesophyll cells, causing leaf discoloration, or “bronzing.” Here, we investigate the inheritance pattern of resistance to leaf bronzing using a three-generation Populus trichocarpa x P. deltoides hybrid pedigree. We found that resistance to the mite is an exaptation in that its source in two related F2 families of the TxD hybrid pedigree was the non-native host, P. deltoides. Two grandparental genotypes of the latter, ‘ILL-5’ and ‘ILL-129’, were completely free of the bronzing symptom and that phenotype was inherited in a Mendelian manner in the F1 and F2. Resistance to S. mesophyllincola is similar to resistance to many other regional pathogens of P. trichocarpa (e.g., Melampsora occidentalis, Venturia inopina, Sphaerulina populicola, and Taphrina sp.) in that it is inherited from the non-native grandparent (e.g., P. deltoides, P. nigra, or P. maximowiczii) in three-generation, hybrid pedigrees. In addition to finding evidence for Mendelian inheritance, we found two QTLs with LOD scores 5.03 and 3.12 mapped on linkage groups (LG) III and I, and they explained 6.7 and 4.2% of the phenotypic variance, respectively. The LG I QTL is close to, or synonymous with, one for resistance to sap-feeding arthropods and leaf developmental traits as expressed in a British study utilizing the same pedigree.

An assemblage of predatory mites (Phytoseiidae) associated with a potential biocontrol agent (Cecidophyes rouhollahi; Eriophyidae) for weed Galium spurium (Rubiaceae)

The weed Galium aparine L., commonly known as cleavers or goose grass, is an exotic plant in New Zealand (Webb et al. 1988; Reid 1998). Craemer et al. (1999) described a new gall mite species, Cecidophyes rouhollahi Craemer (Acari: Eriophyidae), from this weed in France and suggested that this new species might have potential as a biological control agent against G. spurium L. in Canada and western US where the weed was becoming more problematic (Malik & Vanden Born 1988; Whitson 1991). This mite species was later shown to result in severe stunting and complete prevention of seed production in a related weed G. spurium in greenhouse tests and was approved for field release against this weed in Canada (Sobhian et al. 2004). This mite species was recently reported on G. aparine from Auckland, New Zealand (Martin 2017). Mites prefer feeding on the young terminal leaves and can induce the leaf edges to roll inwards and curl (Fig. 1A, B, E). Martin (2017) noted: “No natural enemies of this species of mite have been recorded, but predatory mites may feed on these mites”. We report here on an assemblage of predatory mites (Phytoseiidae) associated with C. rouhollahi on G. aparine in Auckland.

Plant-mediated competition facilitates a phoretic association between a gall mite and a psyllid vector.

Phoretic associations between mites and insects commonly occur in patchy and ephemeral habitats. As plants provide stable habitats for herbivores, herbivorous mites are rarely dependent on other animals for phoretic dispersal. However, a phoretic gall mite, Aceria pallida, which is found on plants, seasonally attaches to a herbivorous insect, Bactericera gobica, for overwintering survival. After detachment, the gall mite shares a habitat with its vector and is likely to compete with this vector for plant resources. However, excessive competition works against the sustainability of the seasonal phoretic association. How the gall mite, as an obligate phoretic mite, balances this relationship with its vector during the growing season to achieve phoresy is unknown. Here, the plant-mediated interspecific interaction between the gall mite and the psyllid after detachment was studied in the laboratory and field. The laboratory results showed that infestation by the gall mite had detrimental effects on the survival and development of psyllid nymphs. Meanwhile, the mite population and the gall size were also adversely affected. The results from the field showed that the mean densities of the mite galls and psyllids were lower in the mixed-species infestation treatment than in the single-species infestation treatment across the investigation period. However, the interspecific interaction between the gall mite and the psyllid decreased rather than accelerated leaf abscission caused by the psyllid, which promoted the persistence of the psyllid population and then indirectly contributed to phoretic association. Our results suggest that the plant-mediated competition between the phoretic gall mite and its vector after detachment facilitates the maintenance of the phoretic association.

Modeling Relative Risk Assesment for Infected Plants by Eriophyoid Mites (Acari, Prostigmata) Using Poisson Log Linear Regression Model

In Poisson regression, the dependent variable of the mite population relative risk assessment can be estimated as based on countable data. Due to disappearing data and numerous uncountable values of the mite population it became difficult to evaluate the risk factor by linear regression methods. The assessment of variable features of mites depending on conditions is very suitable for Poisson regression modeling system. In the this study, the occurrence of rare events such as the occurrence ratio of infected plants was defined by eriophyid mites on two wheat varieties and four different localities. The study was constructed by two way possibility table depending on plant varieties (Triticum aestivum L. and Secale cereale L. (Poaceae) with four locations (Muradiye, Ahlat, Erciş, Doğu Beyazıt and Iğdır). The reference parameters were Triticum aestivum for varieties, and Muradiye for location, respectively. The risk assessment of infected plants for Secale cereale is 1.245 times higher as compared to Triticum aestivum and this difference was found statistically significant (p<0.05). The risk of infected plants for Iğdır location is 1.101 times higher as compared to Muradiye location (p>0.05). In the Poisson log-linear regression, the dependent variable is a risk ratio or a relative risk can be estimated as well as countable data. Thus, Poisson log-linear regression model is a very effective method for analysis of two-way contingency table. Two-way contingency table is created considering the eriophyid mite infection ratio depending on location and varieties, respectively.

ICTV Virus Taxonomy Profile: Fimoviridae.

Members of the family Fimoviridae, order Bunyavirales are plant viruses with segmented, linear, single-stranded, negative-sense RNA genomes. They are distantly related to orthotospoviruses and orthobunyaviruses of the families Tospoviridae and Peribunyaviridae, respectively. The family Fimoviridae includes the genus Emaravirus, which comprises several species with European mountain ash ringspot-associated emaravirus as the type species. Fimoviruses are transmitted to plants by eriophyid mite vectors and induce similar characteristic cytopathologies in their host plants, including the presence of double membrane-bound bodies in the cytoplasm of the virus-infected cells. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Fimoviridae, which is available at www.ictv.global/report/fimoviridae.

Factors affecting the local distribution of Polystigma rubrum stromata on Prunus spinosa

Background and aims – Polystigma rubrum forms orange-red stromata on the surface of living leaves of Prunus spinosa and P. domestica. Records suggests that this fungus now has a much more limited distribution in Britain than recorded in the 19th and early 20th century. Methods – We studied the local distribution of the fungus in the Burren Hills of western Ireland where it remains very common. Key results – Assessment of the local distribution of the fungus over two years found stromata to occur more frequently on P. spinosa leaves in hedgerows than woodlands. On individual trees in areas of open limestone pavement, the frequency of stromata was ten times higher in 2016 than 2015, possibly related to interannual rainfall differences. On hedgerow trees subjected to winter flooding, stromata were much less abundant, whereas stromata were more abundant on leaves also infected by the gall mite Eriophyes prunispinosae. The identity of Po. rubrum was confirmed by ITS sequencing.Conclusion – At a field location where Po. rubrum stromata are present in unusually high abundance, the distribution of stromata on trees in different habitats showed high levels of variation linked to both habitat and the presence of gall mites. Further work is required to determine whether variation in leaf surface and soil moisture are the key determinants of the observed distribution. Such investigations may reveal why Po. rubrum, once common in northern Europe is now restricted mainly to westerly, coastal locations.

First Report of an Emaravirus Associated with Witches' Broom Disease and Eriophyid Mite Infestations of the Blue Palo Verde Tree in Arizona.

First Report of an Emaravirus Associated with Witches' Broom Disease and Eriophyid Mite Infestations of the Blue Palo Verde Tree in Arizona.

Effect of temperature and diet on the morphology of Euseius concordis (Acari: Phytoseiidae)

Mite identification is usually done by the examination of morphological characteristics, the variation of which is not always sufficiently known to allow reliable distinction between closely related species. Morphological variations can be associated with geographical distribution and/ or with host ranges. The objective of this study is to evaluate the morphological variations of a population of a predatory mite identified as Euseius concordis (Chant) (Phytoseiidae) collected in Piracicaba, southeastern Brazil, when reared at different combinations of temperatures (20°C or 28°C) and diets (pollen of Typha domingensis Pers or the eriophyid mite Aceria litchii (Keifer)). High variations were observed even among mites of each treatment. Temperature (especially) and diet caused significant changes in the dimensions of some structures. Extreme cases corresponded to the maximal lengths of the dorsal idiosomal setae z2 and z4, which were about twice their minimal lengths. It is argued that for practical taxonomic purposes, it is more relevant to determine the range of the variation of each structure than its mean or other statistical parameters describing populational variations.

Key Plant, Key Pests: Chinese Elm (Ulmus parvifolia)

This series of Key Plant, Key Pests publications are designed for Florida gardeners, horticulturalists and landscape professionals to help identify common pests associated with common Florida flora. This publication, the second in the Key Plant, Key Pests Series, helps identify the most common pests found on the Chinese Elm (Ulmus parvifolia). This publication provides information and general management recommendations for anthracnose or black elm spot, powdery mildew, trunk canker, borers, eriophyid mites and leaf beetles.https://edis.ifas.ufl.edu/ep559

Geographic distribution of Phyllocoptruta oleivora in the Mediterranean Basin, with particular emphasis on Italy

Phyllocoptruta oleivora (Ashmead) is an eriophyid mite extremely dangerous in several Citrus growing areas. During the 60s, its presence was wrongly suspected in Italy, limited to Sicily, but it has never been confirmed later. Since that time, the record of this mite has been confusing often denied often considered true, without any further investigation on this aspect, causing therefore negative effects on the international trade of citrus fruit from Sicily. Authors so started paying attention to the pest distribution in Italy and other Mediterranean areas, and stressed the importance of a correct specific identification based on the real responsible biological agent of an infestation, its economic relevance and implications for phytosanitary regulations.

Swirski Mite Controlled-release Sachets as a Pest Management Tool in Container Tree Production

Adoption of biological control tools in woody ornamental nursery production has lagged behind other agriculture fields. One of the major obstacles to adoption is lack of information on the efficacy of various biological control agents in nursery production systems. The predatory mite Amblyseius swirskii, sold commercially as “swirski mite,” is a generalist predatory mite that has recently been adopted as a generalist control for a wide range of mite and insect pests, including thrips (Thripidae), whiteflies (Aleyrodidae), eriophyid mites (Eriophyidae), broad mite (Polyphagotarsonemus latus), and spider mites (Tetranychidae). A controlled-release sachet formulation of swirski mite was evaluated in three experiments to determine whether size of the tree, timing of first application, or sun intensity would affect treatment efficacy. Pest numbers on plants was evaluated biweekly for 12 weeks. The swirski mite sachets controlled broad mite and spider mite outbreaks on red maple trees (Acer rubrum) grown in nos. 3 and 15 nursery containers, respectively. Application at the time of red maple rooted cutting transplant was not necessary to achieve summer-long control of pests. No outbreaks of target pests on flowering dogwood (Cornus florida) in no. 5 containers grown under both full sun and shade, but with low levels of broad mite persisting in the shade treatment and thrips persisting in sun. These results suggest that swirski mite is a promising candidate for biological control in woody ornamental nursery production.

Challenges of Breeding Rose Rosette–resistant Roses

Rose rosette disease (RRD) whose causal agent, the Emaravirus Rose rosette virus (RRV), was only recently identified has caused widespread death of roses in the midwestern and eastern sections of the United States. A national research team is working on the detection and best management practices for this highly damaging disease. Unfortunately, little is known about the host plant resistance to either the causal viral agent or its vector, the eriophyid mite Phyllocoptes fructiphilus. Thus far, the only confirmed resistance is among Rosa species. Of the over 600 rose cultivars observed, only 7% have not exhibited symptoms of RRD. Replicated trials are in progress to confirm resistance and/or susceptibility of ≈300 rose accessions in Tennessee and Delaware. Rose is a multispecies cultivated complex that consists of diploid, triploid, and tetraploid cultivars. The basic breeding cycle is 4 years with a 3-year commercial trial coupled with mass propagation before release. Thus, if only one breeding cycle is needed, a new cultivar could be produced in 7 years. Unfortunately, for the introgression of a new trait such as disease resistance from a related species into the commercial rose germplasm, multiple generations are required which can easily take two decades from the first cross to cultivar release. Research is ongoing to develop a rapid selection procedure for resistance to RRD with the aid of molecular markers associated with the resistance. Such an approach has the potential of reducing the breeding cycle time by 50% and increasing the efficiency of seedling and parental selection manifold, leading to commercially acceptable rose cultivars with high RRD resistance in less time and with less expense.

What is Rose Rosette Disease?

Rose rosette disease (RRD) is incited by a negative-sense RNA virus (genus Emaravirus), which is vectored by a wind-transported eriophyid mite (Phyllocoptes fructiphilus). Symptoms include witches broom/rosette-type growth, excessive prickles (thorns), discolored and distorted growth, and, unlike most other rose diseases, usually results in plant death. RRD is endemic to North America and was first described in Manitoba, Wyoming, and California in the 1940s. It has spread east with the aid of a naturalized rose species host and has become epidemic from the Great Plains to the East Coast of North America on garden roses in home and commercial landscapes where losses have been high. The disease was suggested to be incited by a virus from the beginning, but only recently has this been confirmed and the virus identified. The presence of the vector mite on roses has been associated with RRD since the first symptoms were described. However, more recently, the mite was demonstrated to be the vector of the disease and confirmed to transmit the virus itself. As a result of the RRD epidemic in North America and its effects on the national production and consumer markets for roses, a research team comprising five major universities (Texas, Florida, Tennessee, Oklahoma, and Delaware), a dozen growers and nurseries (all regions), six rose breeding programs (California, Wisconsin, Texas, and Pennsylvania), the major rose testing programs (Earth-Kind and AGRS), the major rose organization (American Rose Society), and the major trade organization AmericanHort has formed. This research project has been funded by the Specialty Crops Research Initiative through the U.S. Department of Agriculture (USDA) with the short-term objective of improving and disseminating best management practices (BMPs) and the long-term goal of identifying additional sources of resistance and developing the genetic tools to quickly transfer resistance into the elite commercial rose germplasm.

Re- description of adult stages and description of immature stages of Aceria tristriatus (Nalepa, 1890), from western Iran

Aceria tristriatus (Nalepa, 1890) is one of the major pests of walnut (Juglans regia L.: Juglandaceae) in Iran, especially in western of country. It causes galls on leaves that mainly concentrated along the main and lateral veins. The gall forms toward the upper surface of the leaf with the opening on the lower side. This paper reports the re–description of adult stages (protogyne, deutogyne and male) and description of immature stages of walnut leaf gall mite. Furthermore difference between all mobile stages in this species based on morphological characteristics is provided. Mites were collected from walnut trees infested with this pest in Hamedan and Lorestan provinces, western Iran

Population dynamics of pests on Jasminum Multiflorum

Jasminum multiflorum is infested majorly by bud borers, eriophyid mite, shoot web worm and thrips. Study on the population dynamics of these focusing on their seasonal incidence, correlation and multiple regression analyses with weather factors was carried out at the Regional Horticultural Research and Extension Centre and Department of Entomology, College of Horticulture, Bengaluru. The results revealed that morning relative humidity was the best predictor of bud worm incidence with significant negative correlation. Similarly, rainfall was identified for the shoot web worm with positive correlation, maximum temperature for thrips with positive correlation, and both morning and evening relative humidity for eriophyid mite with negative correlation. The incidence of bud and shoot worm had no significant correlation with any of the considered weather parameters.

Potential of Monitoring for Some Species of Eriophyid Mites by Using Suction Devices Developed for Capturing Small Insects in Tea Fields

Potential of Monitoring for Some Species of Eriophyid Mites by Using Suction Devices Developed for Capturing Small Insects in Tea Fields