Beating Tray Samples Research Articles

Insect pests associated with Andean lupin (Lupinus mutabilis Sweet) and their parasitoids in Peruvian central coast – (Lima, La Molina)

This survey aimed to determine the insect pests associated with Andean lupin ( Lupinus mutabilis Sweet) and its parasitoids, under Peruvian central coast conditions. Sampling was made every seven days with the following methods: linear meter evaluations, plant organ evaluations, pitfall traps, and beating trays. Infested plant organs were taken to the laboratory for adult insect recovery (phytophagous or parasitoids). Pitfall traps and beating tray samples were also processed and stored. During the survey, 14,051 individuals belonging to 11 orders and 91 families were recorded. Insects that infested Andean lupin were Melanagromyza lini Spencer (stem borer), Liriomyza huidobrensis (Blanchard) (leafminer), Crocidosema aporema (Walsingham) (budborer), Grammopsoides tenuicornis (Casey) (stem borer) and Frankliniella occidentalis (Pergande) (bud and flower thrips). Diglyphus websteri (Crawford), D. begini (Ashmead), Chrysocharis flacilla (Walker), C. caribea Boucek, Chrysocharis sp. and Halticoptera arduine (Walker) were recorded as parasitoids of L. huidobrensis , whereas Carcelia sp. was recorded for C. aporema .

Differences in abundance and diversity of diurnal invertebrates among three Fijian forests, and a comparison of two trapping methods for rapid assessments

Apart from some high-profile exceptions (e.g. charismatic long-horned beetles), the ecology and conservation of Fijian invertebrates have received little research attention, and their potential as biodiversity surrogates or indicators is poorly understood. We surveyed diurnal terrestrial invertebrates within three Fijian forest types (lowland, upland, and coastal) using Malaise traps and beating trays to compare invertebrate abundance and diversity among forests. We also evaluated the efficiency of the two trapping methods for rapid invertebrate assessments. Overall, we collected 2584 invertebrates representing 321 morphospecies within 22 arthropod orders. We found significant differences in the abundance and diversity of invertebrates among forest sites for beating-tray samples, but not for Malaise-trap samples. Upland forest had the greatest diversity (Simpsons diversity index, D = 0.98); coastal forest recorded the lowest diversity (D = 0.14), but the greatest abundance of invertebrates. Several orders of invertebrates were relatively abundant across sites and traps (i.e. had high sampling reliability; they included Coleoptera, Hemiptera, Hymenoptera, Lepidoptera, and Diptera), so could be targeted as surrogates for broader biodiversity sampling. Given the urgency with which baseline data are needed across the South Pacific, invertebrate sampling provides a rapid biodiversity assessment tool, including for working in remote areas with few resources.

Effect of introductions of a predator complex on spider mites and thrips in a tunnel and an open field of pesticide-free everbearer strawberry

BACKGROUND: Chemical control of spider mites and thrips in everbearer strawberry is difficult as few efficient chemicals are available and residues represent a risk. In the north the success of biocontrol of mites and thrips in open fields compared with tunnels needs to be evaluated. OBJECTIVES: To investigate the need for control of spider mites and thrips and evaluate the effectiveness of biological control agents in everbearer strawberry. METHODS: Similar experimental plots, in a tunnel and an open field, planted with three everbearer strawberry varieties were arranged to compare the effect of introductions of the spider mite predator Phytoseiulus persimilis and releases of the generalist predatory mites Neoseiulus cucumeris and Neoseiulus barkeri and a predatory bug, Orius majusculus. Several sampling methods were used to evaluate mite and thrips populations. RESULTS: Phytoseiulus persimilis was successful against spider mites. Naturally occurring cecidomyiid and staphylinid predators affected control positively. Thrips damage remained mostly tolerable. The dominant thrips species were Thrips major, Thrips atratus, Thrips vulgatissimus and Frankliniella intonsa. Thrips numbers in the beating tray samples correlated with thrips damage to berries. CONCLUSIONS: Predatory mites were effective in controlling spider mites in an open field and a tunnel. The need for thrips control depended on the strawberry variety. Naturally occurring predators contributed to the control of spider mites and thrips.

Color preference, seasonality, spatial distribution and species composition of thrips (Thysanoptera: Thripidae) in northern highbush blueberries

We investigated color preference, seasonal abundance, spatial distribution and species composition of thrips in northern highbush blueberries, Vaccinium corymbosum L., in New Jersey (USA). White sticky traps were more attractive to thrips compared with yellow or blue traps. Thrips captures using white sticky traps showed that their flight activity begins 20–30 d after the onset of flowering, with 10, 50 and 90% of trap captures observed at 383, 647 and 1231 degree-day accumulations, respectively (10 °C base temperature). Two methods were used to study thrips distribution within a blueberry bush. First, white sticky traps were placed within the bush canopy at three different heights. The highest numbers of thrips were caught on traps in the middle and top one-third of the canopy while the lowest numbers were caught in the bottom one-third. A second method determined the distribution of thrips on the blueberry plant at different heights and phenological stages. The highest numbers of thrips were found on young leaves at lower parts of the canopy, whereas flowers and fruit had fewer thrips and none were found on buds; these thrips were identified as, Scirtothrips ruthveni (88% of adults) and Frankliniella tritici (12%). The distribution of thrips within a blueberry planting was investigated using an evenly-spaced grid of white sticky traps in combination with on bush beating-tray samples. Thrips counts from traps correlated with direct counts on the bush across the entire blueberry field (macro-scale level); however, within the field (micro-scale level), there was no correlation between the number of thrips on traps and on individual bushes near traps. Early in the season, trap counts were higher on bushes closer to the forest, indicative of movement of thrips from wild hosts into blueberry fields. However, this was not the case for direct on bush counts or trap counts for the later part of the season, where there was no clear forest “edge” effect. Percent fruit injury due to thrips feeding was low, and it correlated with thrips counts on bushes but not from counts on traps. Overall, our data show that thrips counts on sticky traps need to be interpreted with care because these numbers weakly correlated with the numbers of thrips on bushes at the micro-scale level and percent fruit injury; however, they can be useful predictors of thrips activity across entire blueberry fields (macro-scale).

Araneofauna (Arachnida; Araneae) do Parque Estadual do Turvo, Rio Grande do Sul, Brasil

A região Neotropical é considerada pouco amostrada com relação à sua araneofauna, carecendo de inventários padronizados que possam servir de base para estudos de biodiversidade. As aranhas são consideradas como importantes componentes dos ecossistemas florestais e aparentam ser organismos ideais para estudos de padrões de biodiversidade. Neste estudo foi efetuado um levantamento da riqueza e composição da fauna de aranhas do Parque Estadual do Turvo, Rio Grande do Sul, Brasil, local que protege o único remanescente representativo da Floresta do Alto Uruguai no Brasil. Foram realizadas quatro expedições semestrais, durante dois anos, no outono e na primavera (2003-2005). Como principal técnica de coleta foi empregado o guarda-chuva entomológico, com o qual amostou-se a vegetação arbóreo-arbustiva da borda da floresta nas estradas internas do Parque. Adicionalmente, foram utilizadas armadilhas de solo, extratores de Winckler, coletas manuais noturnas e amostragens aleatórias. Índice de diversidade de Shannon-Wiener (H’) e curvas de rarefação foram calculados para as coletas com o guarda-chuva entomológico. Incluindo todos os métodos, foram coletadas 8724 aranhas pertencentes a 37 famílias. Cerca de 34% (2946) constituíram-se de aranhas adultas, pertencentes a 31 famílias, 157 gêneros e 447 morfoespécies. A maior riqueza de espécies foi registrada para Salticidae (23%), seguida de Araneidae (18%), Theridiidae (16%) e Thomisidae (9%). Nas amostragens com guarda-chuva entomológico foram registradas 29 famílias; as mais abundantes (incluindo jovens) foram: Salticidae (23%), Araneidae (18%), Thomisidae (14%), Theridiidae (12%) e Anyphaenidae (12%). Dezenove espécies apresentaram abundância superior a 1% do total de indivíduos adultos coletados com esta metodologia. As mais abundantes, foram Thwaitesia affinis O. P.-Cambridge, 1881 (Theridiidae), Tariona sp. 1 (Salticidae) e Misumenops argenteus (Mello-Leitão, 1929) (Thomisidae). Nas primaveras registraram-se as maiores abundâncias de adultos e maiores riquezas de espécies; já, a diversidade de Shannon-Wiener (H’) foi maior em ambos os períodos de outono, devido ao menor número de singletons registrados. As curvas de rarefação não alcançaram a assíntota, sugerindo a existência de espécies não amostradas. A riqueza de aranhas registrada neste levantamento é a maior já encontrada para o Rio Grande do Sul, e a segunda maior registrada para o Brasil. Estes resultados denotam a importância deste ecossistema na conservação da biodiversidade do país.

Species richness and seasonality of spiders (Arachnida, Araneae) in an urban Atlantic Forest fragment in Northeastern Brazil

Species richness and forest seasonality of spiders in an urban fragment of Northeastern Brazil were investigated. Mata do Buraquinho is a remnant of Atlantic Rain Forest where no spider inventories have ever been made. Samplings during dry and wet seasons were carried out in order to establish if seasonality influences species richness and complementarily of the spider fauna. Pitfall traps, nocturnal collections, and beating tray samples were used to access a multi-guild spider fauna. Spider species were estimated using first order Jackknife method. Four hundred samples were obtained, resulting in 1681 adult spiders. A total of 166 species were recorded and 211 were estimated. No significant differences for species richness were observed between both periods, and the captured species were the same according to the complementarily coefficients. The fragmentation hypothesis as factor of biota impoverishment was not tested, but future investigations on this topic are suggested in the complex of forest remnants in Joao Pessoa.

Canopy insect herbivores in the Azorean Laurisilva forests: key host plant species in a highly generalist insect community

This article explores patterns of insect herbivore distribution in the canopy of the Laurisilva forests on seven islands in the Azores archipelago. To our knowledge, this is one of the first extensive study of this type in tree or shrub canopies of oceanic island ecosystems. One of the most frequently debated characteristics of such ecosystems is the likely prevalence of vague, ill‐defined niches due to taxonomic disharmony, which may have implications for insect‐plant interactions. For instance, an increase in ecological opportunities for generalist species is expected due to the lack of predator groups and reduced selection for chemical defence in host plants. The following two questions were addressed: 1) Are specialists species rare, and insect herbivore species randomly distributed among host plant species in the Azores? 2) Are the variances in insect herbivore species composition, frequency and richness explained by host plants or by regional island effects? We expect a proportional distribution of herbivore species between host plants, influenced by host frequency and distinct island effects; otherwise, deviation from expectation might suggest habitat preference for specific host tree crowns. Canopy beating tray samples were performed on seven islands, comprising 50 transects with 1 to 3 plant species each (10 replicates per species), giving 1320 samples from ten host species trees or shrubs in total. From a total of 129 insect herbivore species, a greater number of herbivore species was found onJuniperus brevifolia(s=65) andErica azorica(s=53). However, the number of herbivore species per individual tree crown was higher forE. azoricathan for any other host, on all islands, despite the fact that it was only the fourth more abundant plant. In addition, higher insect species richness and greater insect abundance were found on the trees of Santa Maria Island, the oldest in the archipelago. Insect species composition was strongly influenced by the presence ofE. azorica, which was the only host plant with a characteristic fauna across the archipelago, whereas the fauna of other plant crowns was grouped by islands. The great insect occurrence onE. azoricareflects strong habitat fidelity, but only four species were clearly specialists. Our findings indicate a broadly generalist fauna. The simplicity of Azorean Laurisilva contributed to the understanding of insect‐plant mechanisms in canopy forest habitats.

The effects of artificial weed strips on diversity and abundance of the arthropod fauna in a Swiss experimental apple orchard

The effects of weed strip management on the diversity and abundance of predators of aphids and their potential alternative prey were studied in a commercial apple orchard in Switzerland. In April 1992, selected weeds were sown in strip from between tree rows and along the border in one part of the orchard (the other served as a control). In both parts of the orchard, visual controls and beating tray samples on the apple trees were carried out from March to November in the years 1992 and 1993. At the same time, yellow trap samples and sweep net samples were taken in the ryegrass and weed strips. No significant difference in species diversity could be found between the strip-managed area and the control area, neither for predators of aphids nor for alternative prey. However, the strip-managed area was colonised by predators and alternative prey in significantly higher numbers than the control. The possible factors influencing the effect of the weed strips on predators and on the alternative prey are discussed.

Control of the Codling Moth with Experimental Insecticides, 1994

Abstract The trial was conducted in a 30 yr old Bartlett pear block with chemicals applied to 4 single tree replicates arranged in a RCB. Materials were applied with conventional, high pressure hand gun equipment and sprayed to runoff or about 400 gpa. Each chemical was applied three times in a season-long, phenologically timed CM program. Two different timings were employed, based on CM biofix as determined by the first male moth captured in pheromone baited traps. A standard larvicidal timing was used in treatments receiving Guthion, A 303,603 and one treatment of RH 5992. This standard program consisted of a first application at about 250 degree days (dd) following biofix; the second 28 days later and the final at about 1250 dd, or 250 dd after the predicted emergence of second generation moths. Corresponding dates to the above schedule were 12—13 May, 9 Jun and 13 Jul. An ovicidal timing was employed for the insect growth regulator (IGR) fenoxycarb. The timings for fenoxycarb was a first application at 50-100 dd after biofix (27 Apr), the second 28 days after the first, and the third at 1050 dd (7 Jul). Evaluation of CM damage was made by recording the number of larval entries per 50 fruit per replicate at the end of the first CM generations (7-9 Jul) and again at harvest (17 Aug). Densities of PP immatures, spider mites (TSM, ERM) and PRM were estimated at three post-treatment intervals (20 Jun, 25 Jul, 16 Aug) by recording their numbers from brushing of 20 leaves (10 old, 10 new) per replicate. Adult PP and predators (lacewings, earwigs, and predaceous bugs) were estimated from two beating tray samples per replicate taken on 22 Jun, 27 Jul, and 19 Aug.

Pear, Pink and Petal Fall Timing of Manzate, 1993

Abstract Applications were made to 20 year-old Bosc and Cornice pear trees using a commercial air-carrier sprayer set to deliver 200 gpa. Each treatment was composed of 5, 20-tree replicates. Manzate 200 DF at either 6 or 8 lb formulated/acre was applied at pink bud (5 Apr), petal fall (28 Apr) or at both timings. Morestan 25 WP (5 lb/ac) was applied at the pink stage and used as the standard treatment. Estimates of PP nymphal densities were made by counts on 20 fruit cluster leaves/rep. Adult PP were recorded from 3 beating tray samples per replication.

Early Season Control of Pear Psylla, 1993

Abstract Treatments were applied to 30 year old “Bartlett” pear trees located at the Hanley Farm of Oregon State University’s Southern Oregon Experiment Station near Medford, OR. Plots consisted of 3, 6-tree replicates arranged in a random block design and sprayed to runoff with a Bean handgun sprayer at 250 psi. The spray timings utilized were delayed dormant (11-12 Mar) and pink bud (25-26 Mar) or pink bud and petal fall (26 Apr). NTN-33893 was applied only at the delayed dormant period. PP adult densities were estimated by counting individuals falling onto a cloth covered beating tray after tapping 3 limbs per replicate per treatment. Immature PP were estimated by counting nymphs on 15 fruit spurs (swollen bud) per replicate, 15 fruit clusters (open bud) per replicate or by brushing 15 fruit cluster leaves (small fruit stage) per replicate. Numbers and kinds of PP predators were also recorded from the beating tray samples.

Sampling for Lygus hesperus (Hemiptera: Miridae) in Strawberries

Several suction sampling devices were compared with a beating tray and a whole-plant sample for determining population abundance of Lygus hesperus (Knight) as well as some beneficial predatory arthropods (Geocoris spp., Hemerobius spp., Chrysopa camea (Stephens), Orius tristicolor (White), and spiders) in California strawberry fields. The Allen-vac (A-vac) sampler best approximated the whole-plant sample for L. hesperus and beneficials except spiders. The beating tray provided the most consistent though lower estimates, but could provide a useful estimate of L. hesperus and beneficial arthropod abundance in an integrated pest management monitoring program. The D-vac provided a slightly lower estimate of L. hesperus density than did the A-vac samples or beating-tray samples at a greater cost in sampling time. For each regression of relative technique against the corresponding whole-plant estimate, the intercept was not significantly different from 0. Taylor’s power law was used to develop variance-mean models for each sampling type tested.

Seasonality of Catch of Pear Psylla Cacopsylla pyricola (Homoptera: Psyllidae) on Yellow Traps

Sampling of summer form and winter form pear psylla, Cacopsylla pyricola (Foerster), was undertaken during four years and in two orchards using three methods: yellow sticky traps, clear sticky traps, and beating tray (limb jar techniques). Catches on yellow and clear sticky traps were positively correlated; correlations between trap catches and beating tray numbers tended to be nonsignificant. Catch of summer forms and fall populations of winter forms was much greater on yellow traps than on clear traps. In early spring (before bud break) clear traps captured as many or more psylla than yellow traps; but yellow traps caught far more psylla as green tissue appeared on pear trees. Differences in numbers caught on the two colors were larger for traps hung at the higher of two heights; however, in percentage terms (percentage of total captures occurring on yellow), no position effects were noted. Catches of spring populations of winter forms on sticky traps were highly biased toward male psylla. Similar trends in sex ratio bias were noted for the earliest spring beating tray samples; male bias decreased on successive sampling dates.

Seasonal Phenology and Biology of Calocoris norvegicus (Hemiptera: Miridae) in Pistachios and Associated Host Plants

The biology and seasonal phenology of Caloeoris norvegieus (Gmelin) were studied in pistachios, Pistaeia vera L., and associated host plants in the laboratory and four orchards in the Sacramento Valley. Nymphs were found in weeds in the orchards from late March; adults were found in early April and disappeared by late May. In beating-tray samples, adults were observed on pistachio clusters from 12 April until 25 May. Increases in numbers of adults in the beating-tray samples corresponded to high levels of epicarp lesion, ranging from 11 to 34%. Dispersal to pistachios coincided with the development of adults and was correlated with the drying of orchard weeds or cutting of alfalfa. C. norvegicus nymphs and adults were recorded on various host plants, which included several species of legumes, mustards, and orchard grasses. In late March, first instars hatched from diapausing eggs laid in the dried stems of wild radish, Raphanus sativus L., and wheat, Triticum aestivum L. Neither eggs nor first instars were found on pistachio limbs. In the laboratory, survival to adulthood was 92-98% on winter vetch, View villosa Roth, curly dock, Rumex erispus L., and wild radish, and 25% in wild oats, Avena fatua L. Oviposition was observed within all herbaceous hosts except wild oats.

Pear: Pest Control, 1983

Abstract Twenty-year-old pear trees were sprayed with handguns operating at 600 lb/in2 to evaluate pesticides for control of pear pests. Plots consisted of five two-tree replicates in randomized block design. Treatments were evaluated for pear psylla control by counts of adults and nymphs at 2-week intervals. Adults were counted by taking five beating-tray samples per rep. Nymphs were counted from 50-leaf samples per rep. The proximal, distal, and three leaves from between were collected from each of 10 randomly selected shoots. Phytophagous mites were counted from the same leaf samples but mite data are presented for only those dates when populations were dense enough to show differences between treatments. Leaf samples were brushed and resulting slides were examined using a dissecting microscope. Two 10-fruit samples per rep were weighed and tested for firmness with a penetrometer. Soluble solids were measured with a refractometer on samples of the combined juice of each lot of 10 fruit. Pear psylla russet and pear rust mite russet were rated according to US grade standards for fresh market Bartlett pears on samples of 25 fruit per rep. Fruit and foliage were examined for phytotoxicity after each spray date.

Pear, Pear Pest Control, 1983

Abstract Twenty-yr-old Anjou pear trees were sprayed with handgund operating at 600 lb/in2 to evaluate candidate pesticides for control of pear psylla. Plots consisted of five single-tree replicates in randomized block design. Pear psylla densities were estaimated by counts of adults and nymphs at about 2-week intervals. Adults were counted on five beating-tray samples per rep. Nymphs were counted from 50-leaf samples per rep. Leaf samples consisted of proximal, distal and three evenly spaced leaves between from each of 10 terminal shoots. Leaves were brushed and resulting slides were examined under a dissecting microscope. Pear psylla honeydew russet was measured by examining 25-fruit samples at harvest. Damage was recorded according to US grade standards for winter pears. Firmness, soluble solid content and weight were also measured on the fruit.

Dispersion Statistics and Sequential Sampling Plan for Adult Pear Psylla12

Reported here are dispersion statistics associated with a beating-tray method of sampling and sequential sampling procedures which optimize time spent estimating adult pear psylla densities. Psylla pyricola Foerster adults do not form cohesive groups or colonies such as aphids, but they do show a definite contagious distribution. Beating-tray samples taken during the early growing season, before foliage had developed, were slightly more variable, suggesting they were less efficient in estimating density than those taken after foliage developed. Insecticide applications did not affect the dispersion of pear psylla adults. Calculated stop lines for estimating adult pear psylla densities within 50% of the mean indicate minimum samples of 5, 8, and 12 trays at error levels of P = 0.2, 0.1, and 0.05.