scholarly journals Spatial Distribution of Lycorma delicatula (Hemiptera: Fulgoridae) Egg Masses on Tree-of-Heaven, Black Walnut, and Siberian Elm in North America

2019 ◽  
Vol 113 (2) ◽  
pp. 1028-1032 ◽  
Author(s):  
Houping Liu ◽  
Richard J Hartlieb
Keyword(s):  
Spatial Distribution ◽  
Tree Height ◽  
Black Walnut ◽  
Egg Mass ◽  
Egg Masses ◽  
North West ◽  
Tree Of Heaven ◽  
Significant Difference ◽  
Cardinal Direction ◽  
Lycorma Delicatula

Abstract The spatial distribution of Lycorma delicatula (White) egg masses on three species of trees were studied in Pennsylvania. Five tree-of-heaven, five black walnut, and one Siberian elm trees were felled in early spring 2019 to sample for egg masses. Each egg mass was marked for its cardinal direction, position in the tree, height above ground, and spread from the bole. A total of 214 egg masses were found on tree-of-heaven and black walnut, with 38.3, 29.4, 22.0, and 10.3% on the north, west, south, and east quadrant, respectively. No significant difference in cardinal direction was found for either species. Equal number of egg masses were found on branches and boles on tree-of-heaven. However, significantly more egg masses were found on branches (96.5%) compared to boles (3.5%) on black walnut. Egg masses were laid at 0.30–12.92 and 0.70–17.00 m above ground, with most on boles/higher branches and middle/lower branches for tree-of-heaven and black walnut, respectively. Significant effect of height above ground was found for black walnut, with more egg masses found at 4–6 m compared to 0–2, 12–14, and 14–16 m. Significant effect of spread from the bole was found for tree-of-heaven, with more egg masses found at 0–2 m compared to 2–4 and 4–6 m. The 24 egg masses on the Siberian elm were mostly found on east quadrant branches 0–2 m above ground and within 2 m from the bole. Variation in tree branching patterns and difference in egg mass distribution of other forest pests were discussed.

scholarly journals Performance and host association of spotted lanternfly (Lycorma delicatula) among common woody ornamentals

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Osariyekemwen Uyi ◽  
Joseph A. Keller ◽  
Emelie Swackhamer ◽  
Kelli Hoover
Keyword(s):  
Egg Mass ◽  
Broad Host Range ◽  
Insect Performance ◽  
Offspring Performance ◽  
Egg Masses ◽  
Tree Of Heaven ◽  
Range Tree ◽  
Lycorma Delicatula ◽  
The Difference ◽  
Salix Babylonica

AbstractLycorma delicatula (spotted lanternfly) has a broad host range with a strong preference for the invasive host plant from its native range, tree of heaven (Ailanthus altissima); it had long been speculated that L. delicatula could not develop or reproduce without access to tree of heaven. In 2019, we found that this assumption was incorrect, but fitness was reduced in the absence of A. altissima in that the number of egg masses laid was dramatically fewer for insects reared on suitable non-A. altissima host plants that had recently been established. We hypothesized that longer established, larger trees (of the same species) would improve the fitness of L. delicatula in the absence of tree of heaven. In spring 2020, we examined insect performance with and without access to A. altissima by tracking development, survival, host tree association and oviposition in large enclosures with trees planted two years prior to the study. Each enclosure included one each of Juglans nigra, Salix babylonica and Acer saccharinum along with either one A. altissima or one Betula nigra; these trees had twice the diameter of the same trees the previous year. We reared nymphs with and without access to A. altissima, released them into the corresponding large enclosures as third instars, and monitored them from early July 2020 through November 2020. We also determined whether lack of access to A. altissima by parents of L. delicatula have any fitness effects on offspring performance. To ensure adequate adult populations for comparing fecundity between treatments, third instars were released into the multi-tree enclosures due to high mortality in earlier instars that occurred in a similar study in 2019. Insect survival was higher and development faster with access to A. altissima. Third and fourth instar nymphs were most frequently observed on A. altissima when it was present, while adults were equally associated with A. saccharinum and A. altissima. In the absence of A. altissima, nymphs were most frequently found on S. babylonica, while adults were most often on A. saccharinum. Females with access to A. altissima deposited nearly 7-fold more egg masses than those without access to A. altissima, which is consistent with the difference in egg mass numbers between the two treatments the previous year; thus, our hypothesis was rejected. The offspring of parents that had been reared without access to A. altissima showed similar survival and development time from egg to adult as offspring from parents that never had access to A. altissima. These findings suggest that managers need to be aware that even in the absence of A. altissima in the landscape, several hardwood host trees can be utilized by L. delicatula to develop and reproduce, but fitness without A. altissima is likely to still be reduced.

scholarly journals Dispersal and Oviposition Patterns of Lycorma Delicatula (Hemiptera: Fulgoridae) During Oviposition Period in Ailanthus Altissima (Simaroubaceae)

2022 ◽  
Author(s):  
Minhyung Jung ◽  
Jung-Wook Kho ◽  
Do-Hun Gook ◽  
Young Su Lee ◽  
Doo-Hyung Lee
Keyword(s):  
Tree Height ◽  
The United States ◽  
Dispersal Distance ◽  
Oviposition Period ◽  
Ailanthus Altissima ◽  
Egg Mass ◽  
Dispersal Patterns ◽  
Egg Masses ◽  
Lycorma Delicatula ◽  
Positive Correlations

Abstract The spotted lanternfly (SLF), Lycorma delicatula (Hemiptera: Fulgoridae), has the potential to become a global pest and is currently expanding its range in the United States. In this study, we investigated the dispersal patterns of SLF in Ailanthus altissima during its oviposition period in South Korea using fluorescent marking system. Oviposition patterns of SLF were then analyzed by surveying egg masses in A. altissima patches. The recapture rate of fluorescent-marked SLF rapidly decreased < 30% within the first two weeks. During the oviposition period, seven cases of among-patch dispersal of SLF adults were observed with a minimum estimated dispersal distance mainly ranging between 10 - 60 m and a maximum of 1,740 m. Also, the number of A. altissima trees detected with fluorescent-marked SLF increased until late September. Based on the egg mass survey, a total of 159 egg masses were detected from 38 out of 247 A. altissima trees. Furthermore, ca. 80% of egg masses were located < 2.5 m above the ground. Finally, the number of egg masses showed significant positive correlations with the height and diameter at root collar of A. altissima trees; both tree height and DRC were significantly larger from the trees with egg masses.

scholarly journals Oviposition Substrate Selection, Egg Mass Characteristics, Host Preference, and Life History of the Spotted Lanternfly (Hemiptera: Fulgoridae) in North America

2019 ◽  
Author(s):  
Houping Liu
Keyword(s):  
Host Preference ◽  
Fourth Instar ◽  
Egg Mass ◽  
Black Cherry ◽  
Substrate Selection ◽  
Egg Masses ◽  
Tree Of Heaven ◽  
History Of ◽  
Oviposition Substrate ◽  
Substrate Types

Abstract Oviposition substrate selection, egg mass characteristics, host preference, and life history of Lycorma delicatula (White) (Hemiptera: Fulgoridae) were studied in Pennsylvania between 2016 and 2017. Twenty-four substrate types (trees, shrubs, and nonliving materials) were selected by females for oviposition. Tree-of-heaven, black cherry, black birch, and sweet cherry were favored at 62.5% of the types and accounted for 68.5% of the egg masses based on survey results 200 cm above ground. Egg mass density ranged between 0.2 and 75.2 egg masses/m2 with no significant difference among substrate types. Egg mass size ranged between 0 and 192 eggs/egg mass, with 91.8% containing <50 eggs. Significantly larger egg masses were found on sweet and black cherry compared with tree-of-heaven, with significantly higher hatch success on black locust. Eggs hatched between May 2 and June 5 and peaked on 18 May 2017. Tree-of-heaven and summer grape were preferred by nymphs and adults, while multiflora rose and black walnut were favored by the first, second, and the fourth instar nymphs, respectively. The first, second, third, fourth instars and adults lasted for 62 (2 May–3 July), 42 (8 June–20 July), 35 (26 June—31 July), 39 (10 July—18 Aug.), and 114 (24 July—15 Nov.) days, with peaks on 25 May, 22 June, 6 July, 31 July, and 22 Aug., respectively. Adult feed for 2 months before laying eggs in early October. Cumulative degree-days were 0–325, 153–652, 340–881, 567–1,020, 738–1,227, and 942–1,795 for the egg, first, second, third, fourth instar, and adult stage, respectively. Oviposition strategies and development patterns were discussed.

MORTALITY FACTORS AFFECTING EGGS OF THE FOREST TENT CATERPILLAR, MALACOSOMA DISSTRIA (LEPIDOPTERA: LASIOCAMPIDAE)

1972 ◽  
Vol 104 (5) ◽  
pp. 705-710 ◽  
Author(s):  
J. A. Witter ◽  
H. M. Kulman
Keyword(s):  
Larval Mortality ◽  
Malacosoma Disstria ◽  
Egg Mass ◽  
Forest Tent Caterpillar ◽  
Mortality Factors ◽  
Egg Masses ◽  
Factors Affecting ◽  
Egg Mortality ◽  
Significant Difference ◽  
Tent Caterpillar

AbstractParasitism, infertility, and death of fully developed first-stage larvae in eggs (pharate larvae) were the egg mortality factors encountered during a 1967–69 study on the bionomics of the forest tent caterpillar, Malacosoma disstria Hübner, in northern Minnesota. There was no significant difference in the average yearly per cent parasitization and infertility per egg mass; these ranged from 7 to 10% and 1 to 3%, respectively. There was a year to year difference in pharate larval mortality. It ranged from 39% in 1968 to only 9 and 3% for 1967 and 969. Studies showed that egg masses had a tendency to be either nearly complete y hatched or unhatched only in 1968. The variation in pharate larval mortally in these studies suggests qualitative differences in the population. The pharate larval mortality has the potential of influencing population trends of the forest tent caterpillar.

SPATIAL DISTRIBUTION OF ADULTS OFOOENCYRTUS KUVANAE(HYMENOPTERA: ENCYRTIDAE), AN EGG PARASITE OFLYMANTRIA DISPAR(LEPIDOPTERA: LYMANTRIIDAE)

1982 ◽  
Vol 114 (12) ◽  
pp. 1109-1120 ◽  
Author(s):  
M. W. Brown ◽  
E. Alan Cameron
Keyword(s):  
Spatial Distribution ◽  
Gypsy Moth ◽  
Tree Species ◽  
Small Sample ◽  
Egg Mass ◽  
Parasite Abundance ◽  
Egg Masses ◽  
Positive Correlation ◽  
Wide Range ◽  
Mass Volume

AbstractThe spatial distribution of adultOoencyrtus kuvanae(Howard) (Hymenoptera: Encyrtidae) was examined in central Pennsylvania during 1978–1980. Data were gathered over a wide range of gypsy moth (Lymantria dispar(L.) (Lepidoptera: Lymantriidae)) densities and from all phases of population growth. There was a linear relationship between the log variance and log mean, fitting Taylor's Power Law with a power of 1.27. The degree of aggregation inO. kuvanaepopulations, as measured by the variance-to-mean ratio, was correlated positively with the abundance of the parasite, and was independent of host density. Aggregation was believed to result from the habit of the female parasite ovipositing repeatedly on the same egg mass, and the resultant progeny emerging synchronously. Behavior and density ofO. kuvanaepopulations were found to depend upon the gypsy moth population condition, i.e., low, rising, high stable, outbreak, or collapsed. The frequency distribution ofO. kuvanaepopulations fit the Poisson at densities less than 0.2 parasite adult per egg mass, a condition which occurred early and late (July, November) in the season, and the negative binomial above this density; a few distributions fit the log normal. The data were also analyzed using analyses of variance (multivariate and univariate), correlation, and regression techniques. All main effects, i.e., study area, host egg mass volume, egg mass height from the ground (within the 0–2 m sampling universe), aspect of the egg mass on the tree, and tree species, were important in explaining the variance in parasite abundance; study area differences were the most important. The effects of aspect and tree species were explained on the basis of small sample sizes, and not studied further. There was a positive correlation between host egg mass volume (= size) and parasite abundance. There was also a positive correlation between the height of the egg mass and parasite abundance during the summer; however, this relationship became negative by late fall. This seasonal change in vertical distribution was attributed to the tendency ofO. kuvanaeto be closer to the ground where they overwinter. Variation in adult abundance was generally greater among gypsy moth egg masses on different trees than among egg masses on the same tree, except at low parasite densities. This was attributed to the parasites searching for egg masses on one tree before dispersing to another.

DOUGLAS-FIR TUSSOCK MOTH (HEMEROCAMPA PSEUDOTSUGATA) EGG-MASS DISTRIBUTION ON WHITE FIR IN NORTHEASTERN CALIFORNIA

1967 ◽  
Vol 99 (11) ◽  
pp. 1193-1203 ◽  
Author(s):  
Robert F. Luck ◽  
Donald L. Dahlsten
Keyword(s):  
Sampling Method ◽  
Douglas Fir ◽  
Egg Mass ◽  
Egg Masses ◽  
Sample Unit ◽  
Tussock Moth ◽  
White Fir ◽  
Cardinal Direction ◽  
Sources Of Variation ◽  
Cardinal Directions

AbstractThe distribution of Douglas-fir tussock moth (Hemerocampa pseudotsugata McD.) egg-masses on white fir (Abies concolor (Gord. and Glend.) Lindl.) was studied in three areas of northern California. In each area 100 trees between 4.5 and 8.4 in. in diameter were stratified into five defoliation classes and four crown classes, giving a total of 20 classes per study area with five trees per class. Trees were divided into four crown levels and samples were taken at each of the cardinal directions at each level. Two branches comprised n sample unit in the top half of the tree (eight branches per level) and one branch the sample unit in the bottom half of the tree (four branches per level). Egg masses were recorded per 10 sq. ft of foliage or branch area. Eighty per cent or more of the egg masses were found in the bottom half of the crown. This percentage in the bottom half of the crown increased on trees with heavy defoliation or with increased exposure of the crown. Of the four possible sources of variation considered in this study, crown level, defoliation class, and crown class were significant while cardinal direction was not. A sampling method is proposed on the basis of the information gathered in this investigation.

scholarly journals Occurrence, Seasonal Abundance, and Superparasitism of Ooencyrtus kuvanae (Hymenoptera: Encyrtidae) as an Egg Parasitoid of the Spotted Lanternfly (Lycorma delicatula) in North America

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 79 ◽  
Author(s):  
Houping Liu
Keyword(s):  
North America ◽  
Biological Control Agent ◽  
Egg Parasitoid ◽  
Seasonal Abundance ◽  
Egg Mass ◽  
Laboratory Incubation ◽  
Significant Difference ◽  
Lycorma Delicatula ◽  
Ooencyrtus Kuvanae ◽  
Oviposition Sites

The occurrence of egg parasitoid Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae) on its new host, the spotted lanternfly (Lycorma delicatula (White) (Hemiptera: Fulgoridae)), was surveyed at 4 study plots in 2016 and 10 additional plots in 2017 in Pennsylvania through field collection and laboratory incubation. O. kuvanae adults were found on L. delicatula egg mass surfaces at two plots (ODSouth and Lutz) in 2016, but at none in 2017. The results of laboratory incubation showed that O. kuvanae adults were only recovered from host eggs collected at plot ODSouth in 2016, with adults emerging between 22 April and 2 May 2016 at 22 ± 1 °C, 40% ± 5% relative humidity (RH), and a 16:8 h photoperiod (light/dark). The overall parasitism at this study plot was 6.0% by egg mass and 1.2% by egg. Two oviposition sites contained parasitized L. delicatula eggs, with 12.3% (9.5–15.0%) host egg masses and 3.1% (1.3–5.0%) host eggs utilized by the parasitoid. O. kuvanae parasitism by egg was significantly higher on oviposition site ODSouth #7 than on ODSouth #8. No O. kuvanae adults were reared out of field-collected host eggs from the 10 plots in 2017. Seasonal abundance and superparasitism of O. kuvanae was examined at plot ODSouth in 2017. O. kuvanae-parasitized L. delicatula eggs were found on all four oviposition sites based on field monitoring of parasitoid adult emergence, resulting in a parasitism of 35.4% (18.8–55.6%) by egg mass and 2.2% (0.5–3.9%) by egg. No significant difference in parasitism by egg was observed among oviposition sites. O. kuvanae adults emerged in the field between 2 May and 1 June 2017. Superparasitism was confirmed for O. kuvanae on L. delicatula eggs based on parasitoid production (1.0–3.3 adults/parasitized egg) and adult exit holes (1–3 exit holes/parasitized egg). As the first parasitoid recorded from L. delicatula in North America, O. kuvanae has the potential to become an important biological control agent for L. delicatula in North America, with its well-synchronized life history in the spring, century-long field establishment, superparasitism, and female-biased progeny population. L. delicatula complements the gypsy moth well as an alternative host for O. kuvanae in the field.

scholarly journals Seasonal Development, Cumulative Growing Degree-Days, and Population Density of Spotted Lanternfly (Hemiptera: Fulgoridae) on Selected Hosts and Substrates

2020 ◽  
Vol 49 (5) ◽  
pp. 1171-1184
Author(s):  
Houping Liu
Keyword(s):  
Population Density ◽  
Seasonal Development ◽  
Growing Degree Days ◽  
Red Maple ◽  
Degree Days ◽  
Egg Masses ◽  
Tree Of Heaven ◽  
Significant Difference ◽  
Beech Tree ◽  
Specific Species

Abstract Seasonal development, cumulative growing degree-days (CUMDD10), and population density of Lycorma delicatula (White) were studied through weekly sampling of 30 plants (5 plants/species, 3 common plus 3 site-specific species per site) at six sites in Pennsylvania in 2019. In total, 24,159 L. delicatula (1,987 egg masses, 1,068 first instars, 239 second instars, 153 third instars, 410 fourth instars, and 20,302 adults) were recorded in 28 wk. Seasonal development followed similar pattern at all sites despite differences in starting, peaking, and ending time for specific life stages. The average CUMDD10 requirement for the onset of the first instars, second instars, third instars, fourth instars, adults, and eggs was 270, 465, 645, 825, 1,112, and 1,825, respectively. Population density ranged from 0 to 207.4, 0–298.9, and 0–9.6/m2 for nymphs, adults, and egg masses, respectively. Significant difference in population density was found between sites, hosts/substrates, and sampling weeks. Favored oviposition substrates included tree-of-heaven and black birch despite egg masses being laid on many other surfaces. Nymphs fed on different hosts in early stages but preferred American beech, tree-of-heaven, black birch, and multiflora rose. Adults were predominately found on tree-of-heaven with preoviposition surge on black birch and red maple. Sizable nymph and adult populations persisted on summer grape throughout the season. Tree-of-heaven played an irreplaceable role in the seasonal development and life history of L. delicatula in the field. Survey and detection activities should focus on tree-of-heaven with management efforts directed to aggregating adults for maximum efficacy.

scholarly journals Effects of habitat edges on vegetation structure and the vulnerable golden-brown mouse lemur (Microcebus ravelobensis) in northwestern Madagascar

BMC Ecology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Bertrand Andriatsitohaina ◽  
Daniel Romero-Mujalli ◽  
Malcolm S. Ramsay ◽  
Frederik Kiene ◽  
Solofonirina Rasoloharijaona ◽  
...  
Keyword(s):  
Body Mass ◽  
Edge Effects ◽  
Vegetation Structure ◽  
Species Abundance ◽  
Tree Height ◽  
Logistic Function ◽  
Study Region ◽  
Large Trees ◽  
Significant Difference ◽  
Vegetation Parameters

Abstract Background Edge effects can influence species composition and community structure as a result of changes in microenvironment and edaphic variables. We investigated effects of habitat edges on vegetation structure, abundance and body mass of one vulnerable Microcebus species in northwestern Madagascar. We trapped mouse lemurs along four 1000-m transects (total of 2424 trap nights) that ran perpendicular to the forest edge. We installed 16 pairs of 20 m2 vegetation plots along each transect and measured nine vegetation parameters. To determine the responses of the vegetation and animals to an increasing distance to the edge, we tested the fit of four alternative mathematical functions (linear, power, logistic and unimodal) to the data and derived the depth of edge influence (DEI) for all parameters. Results Logistic and unimodal functions best explained edge responses of vegetation parameters, and the logistic function performed best for abundance and body mass of M. ravelobensis. The DEI varied between 50 m (no. of seedlings, no. of liana, dbh of large trees [dbh ≥ 10 cm]) and 460 m (tree height of large trees) for the vegetation parameters, whereas it was 340 m for M. ravelobensis abundance and 390 m for body mass, corresponding best to the DEI of small tree [dbh < 10 cm] density (360 m). Small trees were significantly taller and the density of seedlings was higher in the interior than in the edge habitat. However, there was no significant difference in M. ravelobensis abundance and body mass between interior and edge habitats, suggesting that M. ravelobensis did not show a strong edge response in the study region. Finally, regression analyses revealed three negative (species abundance and three vegetation parameters) and two positive relationships (body mass and two vegetation parameters), suggesting an impact of vegetation structure on M. ravelobensis which may be partly independent of edge effects. Conclusions A comparison of our results with previous findings reveals that edge effects are variable in space in a small nocturnal primate from Madagascar. Such an ecological plasticity could be extremely relevant for mitigating species responses to habitat loss and anthropogenic disturbances.

scholarly journals The Effect of Loneliness on Death Anxiety in the Elderly During the COVID-19 Pandemic

2021 ◽  
pp. 003022282110105
Author(s):  
Türkan Akyol Guner ◽  
Zeynep Erdogan ◽  
Isa Demir
Keyword(s):  
Death Anxiety ◽  
The Elderly ◽  
Average Score ◽  
City Center ◽  
Cross Sectional ◽  
North West ◽  
Significant Difference ◽  
Scale Scores ◽  
Education Status ◽  
At Home

The aim of the study is to determine the effect on death anxiety of loneliness in the elderly during the COVID-19 pandemic. The population of this study that is descriptive and cross-sectional type consist of 354 elderly who meet the inclusion criteria from three different associations operating for charitable purposes in a city center located in north-west Turkey. The average score of Loneliness Scale of Elderly (LSE) of the elderly was determined as 11.39 ± 5.31, and the average score of Death Anxiety Scale (DAS) of the elderly was determined as 8.54 ± 4.82. According to these results, it was found that the elderly experienced acceptable levels of loneliness and moderate death anxiety. A statistically significant difference was found in the LSE and DAS scores of the elderly according to their age, marital status, education status, chronic illness status and living at home with relatives. In addition, during the COVID-19 epidemic, the scale scores of the elderly who have increased worries, who have a hobby at home, and who communicate with their relatives via social media/mobile phones were found to be statistically significant (p < 0.05).

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