scholarly journals Cold Tolerance and Population Dynamics of Leptoglossus zonatus (Hemiptera: Coreidae)

Insects ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 351 ◽  
Author(s):  
Kristen E. Tollerup
Keyword(s):  
Population Dynamics ◽  
Late Summer ◽  
Economic Loss ◽  
San Joaquin Valley ◽  
Destructive Sampling ◽  
Fresno County ◽  
Winter Temperatures ◽  
Early Fall ◽  
Aggregation Size ◽  
Considerable Economic Loss

In California’s San Joaquin Valley, feeding by the coreid pest, Leptoglossus zonatus, can cause considerable economic loss on almond and pistachio. This research was conducted to improve understanding of how winter temperatures affect mortality of overwintering adult L. zonatus and to develop a better understanding of the role pomegranate plays in the species’ life-history. We exposed 7410 field-collected adult L. zonatus to temperatures between −2 and −10 °C for a period of three, four, or six hours using insect incubators. At six hours of exposure, the, LD50 and LD95 occur at −5.8 and −9.7 °C, respectively. We classified L. zonatus as chill-intolerant. Temperatures cold enough to affect substantial mortality of overwintering L. zonatus rarely occur in the San Joaquin Valley. Whole aggregation destructive sampling from a pomegranate hedgerow in Fresno County was conducted to determine population dynamics. At late summer to early fall, aggregations consisted of >90% immature stages. By early to mid-winter, mean aggregation size decreased, consisting of only three to 12 late-instars and adults. During years one and two of the experiment, L. zonatus produced a generation on pomegranate, mostly between September and mid-November. Overwintering did not occur on pomegranate, rather the majority of adults emigrated to other overwintering locations by mid-winter.

The ecology of Honey Creek, Oklahoma: population dynamics and drifting behavior of three species of Simulium (Diptera: Simuliidae)

1977 ◽  
Vol 55 (2) ◽  
pp. 325-337 ◽  
Author(s):  
William K. Reisen
Keyword(s):  
Population Dynamics ◽  
Water Temperature ◽  
Larval Development ◽  
Late Summer ◽  
Diel Changes ◽  
Egg Maturation ◽  
South Central ◽  
Early Fall

The population dynamics and drifting behavior of Simulium virgatum, S. trivittatum, and Simulium species A were investigated at nine stations in a south-central Oklahoma limestone stream from June 1972 through August 1973. Simulium species A abundance paralleled vernal periphyton increases and exhibited characteristic midsummer and midwinter decreases, while S. virgatum and S. trivittatum were most prevalent during late summer and early fall. Simulium species A and S. virgatum oviposited during the evening crepuscular period. In Simulium species A synchronous egg maturation and eclosion apparently imparted a degree of drift rhythmicity in the early instars which progressively degenerated during larval development. Simulium virgatum drift rates were highest during midafternoon and were correlated with diel changes in water temperature. Simulium trivittatum drift rates were highest during the evening and morning and lowest during the afternoon.

Xylella fastidiosa and Glassy-Winged Sharpshooter Population Dynamics in the Southern San Joaquin Valley of California

Plant Disease ◽  
2020 ◽  
Vol 104 (11) ◽  
pp. 2994-3001 ◽  
Author(s):  
Mark S. Sisterson ◽  
Lindsey P. Burbank ◽  
Rodrigo Krugner ◽  
David Haviland ◽  
Drake C. Stenger
Keyword(s):  
Population Dynamics ◽  
Xylella Fastidiosa ◽  
Late Summer ◽  
Early Summer ◽  
San Joaquin Valley ◽  
Pierce's Disease ◽  
Homalodisca Vitripennis ◽  
Pierce’S Disease ◽  
Vector Population ◽  
Pathogen Populations

Xylella fastidiosa is a vector-transmitted bacterial plant pathogen that affects a wide array of perennial crops, including grapevines (Pierce’s disease). In the southern San Joaquin Valley of California, epidemics of Pierce’s disease of grapevine were associated with the glassy-winged sharpshooter, Homalodisca vitripennis. During the growing season, rates of X. fastidiosa spread in vineyards are affected by changes in pathogen distribution within chronically infected grapevines and by vector population dynamics. Grapevines chronically infected with X. fastidiosa rarely tested positive for the pathogen prior to July, suggesting vector acquisition of X. fastidiosa from grapevines increases as the season progresses. This hypothesis was supported by an increase in number of X. fastidiosa-positive glassy-winged sharpshooters collected from vineyards during July through September. Analysis of insecticide records indicated that vineyards in the study area were typically treated with a systemic neonicotinoid in spring of each year. As a result, abundance of glassy-winged sharpshooters was typically low in late spring and early summer, with abundance of glassy-winged sharpshooter adults increasing in late June and early July of each year. Collectively, the results suggest that late summer is a crucial time for X. fastidiosa secondary spread in vineyards in the southern San Joaquin Valley, because glassy-winged sharpshooter abundance, number of glassy-winged sharpshooters testing positive for X. fastidiosa, and grapevines with detectable pathogen populations were all greatest during this period.

Strategies to reduce PM2.5 and O3 together during late summer and early fall in San Joaquin Valley, California

2021 ◽  
pp. 105633
Author(s):  
Lin Huang ◽  
Jinjin Sun ◽  
Ling Jin ◽  
Nancy J. Brown ◽  
Jianlin Hu
Keyword(s):  
Late Summer ◽  
San Joaquin Valley ◽  
Early Fall

scholarly journals Decrease in Enteroviral Meningitis - An Unexpected Benefit of COVID-19 Mitigation?

2020 ◽  
Author(s):  
Kami D Kies ◽  
Amber S Thomas ◽  
Matthew J Binnicker ◽  
Kelli L Bashynski ◽  
Robin Patel
Keyword(s):  
Cerebrospinal Fluid ◽  
Laboratory Testing ◽  
Clinical Microbiology ◽  
Late Summer ◽  
Mitigation Strategies ◽  
Clinical Microbiology Laboratory ◽  
Microbiology Laboratory ◽  
Testing Data ◽  
Early Fall ◽  
Enteroviral Meningitis

Abstract Enteroviral meningitis is seasonal, typically exhibiting a rise in prevalence in late summer/early fall. Based on clinical microbiology laboratory testing data of cerebrospinal fluid, the expected August/September/October peak in enteroviral meningitis did not occur in 2020, possibly related to COVID-19 mitigation strategies.

scholarly journals Inter-seasonal population dynamics and pest status of Bemisia tabaci (Gennadius) biotype B in an Australian cropping system

2008 ◽  
Vol 99 (4) ◽  
pp. 325-335 ◽  
Author(s):  
R.V. Sequeira ◽  
A. Shields ◽  
A. Moore ◽  
P. De Barro
Keyword(s):  
Population Dynamics ◽  
Bemisia Tabaci ◽  
Cropping System ◽  
Late Summer ◽  
System Component ◽  
Cotton Production ◽  
Pest Status ◽  
Weed Host ◽  
Biotype B ◽  
Seasonal Population

AbstractBemisia tabaci, biotype B, commonly known as the silverleaf whitefly (SLW) is an alien species that invaded Australia in the mid-90s. This paper reports on the invasion ecology of SLW and the factors that are likely to have contributed to the first outbreak of this major pest in an Australian cotton cropping system. Population dynamics of SLW within whitefly-susceptible crop (cotton and cucurbit) and non-crop vegetation (sowthistle, Sonchus spp.) components of the cropping system were investigated over four consecutive growing seasons (September–June) 2001/02–2004/05 in the Emerald Irrigation Area (EIA) of Queensland, Australia. Based on fixed geo-referenced sampling sites, variation in spatial and temporal abundance of SLW within each system component was quantified to provide baseline data for the development of ecologically sustainable pest management strategies. Parasitism of large (3rd and 4th instars) SLW nymphs by native aphelinid wasps was quantified to determine the potential for natural control of SLW populations. Following the initial outbreak in 2001/02, SLW abundance declined and stabilised over the next three seasons. The population dynamics of SLW is characterised by inter-seasonal population cycling between the non-crop (weed) and cotton components of the EIA cropping system. Cotton was the largest sink for and source of SLW during the study period. Over-wintering populations dispersed from weed host plant sources to cotton in spring followed by a reverse dispersal in late summer and autumn to broad-leaved crops and weeds. A basic spatial source-sink analysis showed that SLW adult and nymph densities were higher in cotton fields that were closer to over-wintering weed sources throughout spring than in fields that were further away. Cucurbit fields were not significant sources of SLW and did not appear to contribute significantly to the regional population dynamics of the pest. Substantial parasitism of nymphal stages throughout the study period indicates that native parasitoid species and other natural enemies are important sources of SLW mortality in Australian cotton production systems. Weather conditions and use of broad-spectrum insecticides for pest control are implicated in the initial outbreak and on-going pest status of SLW in the region.

Cattle Foraging Behavior in Leafy Spurge (Euphorbia esula)-Infested Rangeland

1987 ◽  
Vol 1 (4) ◽  
pp. 314-318 ◽  
Author(s):  
Rodney G. Lym ◽  
Donald R. Kirby
Keyword(s):  
Warm Season ◽  
Economic Loss ◽  
Leafy Spurge ◽  
High Density ◽  
Euphorbia Esula ◽  
Low Density ◽  
Forage Production ◽  
Grazing Season ◽  
Grazing Cattle ◽  
Early Fall

Leafy spurge causes economic loss by reducing both herbage production and use. Herbage use by grazing cattle in various densities of leafy spurge (Euphorbia esulaL. #3EPHES) was evaluated over a 3-yr period in North Dakota. Forage production and disappearance were estimated in four density classes of leafy spurge. Use of cool- and warm-season graminoids, forbs, and leafy spurge was estimated during the middle and the end of each grazing season. Cattle used 20 and 2% of the herbage in the zero and low density infestations, respectively, by mid-season. Moderate and high density infestations were avoided until the milky latex in leafy spurge disappeared in early fall, and herbage availability in zero and low density infestations declined. Herbage use in moderate and high density infestations increased to an average of 46% by the end of the grazing season compared to 61% in zero and low density infestations. An annual herbage loss of at least 35% occurred in pasture infested with 50% density or more of leafy spurge.

scholarly journals A biodiversity hotspot for Microgastrinae (Hymenoptera, Braconidae) in North America: annotated species checklist for Ottawa, Canada

ZooKeys ◽  
2016 ◽  
Vol 633 ◽  
pp. 1-93 ◽  
Author(s):  
Jose Fernandez-Triana ◽  
Caroline Boudreault ◽  
Joel Buffam ◽  
Ronald Maclean
Keyword(s):  
North America ◽  
General Pattern ◽  
Late Summer ◽  
The United States ◽  
Early Summer ◽  
Individual Species ◽  
Early Fall ◽  
Two Peaks ◽  
Annotated Checklist ◽  
First Time

Microgastrinae wasps (Hymenoptera, Braconidae) from the city of Ottawa and its surroundings (a 50-km radius circle, ~7,800 km2) were studied based on 1,928 specimens collected between 1894 and 2010, and housed in the Canadian National Collection of Insects. A total of 158 species from 21 genera were identified, which is by far the highest number of species ever recorded for a locality in North America. An annotated checklist of species is provided.Choerasparasitellae(Bouché, 1834) andPholetesornanus(Reinhard, 1880) are recorded for the first time in the Nearctic (previously only known from the Palearctic region),Cotesiadepressa(Viereck, 1912) is recorded for the first time in Canada (previously only known from the United States), andCotesiahemileucae(Riley, 1881) andProtapantelesphlyctaeniae(Muesebeck, 1929) are recorded for the first time in the province of Ontario. In Ottawa the most diverse genera areCotesia,Apanteles,Microplitis,Pholetesor,Microgaster, andDolichogenidea, altogether comprising 77% of the species found in the area. A total of 73 species (46%) were represented by only one or two specimens, suggesting that the inventory for Ottawa is still relatively incomplete. Seasonal distribution showed several peaks of activity, in spring, summer, and early fall. That general pattern varied for individual species, with some showing a single peak of abundance either in the summer or towards the end of the season, others species attaining two peaks, in late spring and late summer, or in early summer and early fall, and yet others attaining up to three different peaks, in spring, summer and fall. At least 72 of the Microgastrinae species from Ottawa have been previously associated with 554 species of Lepidoptera as hosts – but those historical literature records are not always reliable and in many cases are based on data from areas beyond Ottawa. Thus, our knowledge of the associations between the 158 species of microgastrine parasitoids and the caterpillars of the 2,064 species of Lepidoptera recorded from Ottawa is still very incomplete.

scholarly journals Changes in historical typhoid transmission across 16 U.S. cities, 1889-1931: Quantifying the impact of investments in water and sewer infrastructures

2019 ◽  
Author(s):  
Maile T. Phillips ◽  
Katharine A. Owers ◽  
Bryan T. Grenfell ◽  
Virginia E. Pitzer
Keyword(s):  
Late Summer ◽  
Water Source ◽  
Developed Countries ◽  
The United States ◽  
Water And Sanitation ◽  
Sewer Systems ◽  
Early Fall ◽  
Sanitation Systems ◽  
The Impact

ABSTRACTBackgroundInvestments in water and sanitation systems are believed to have led to the decline in typhoid fever in developed countries, such that most cases now occur in regions lacking adequate clean water and sanitation. Exploring seasonal and long-term patterns in historical typhoid mortality in the United States can offer deeper understanding of disease drivers.MethodsWe fit modified Time-series Susceptible-Infectious-Recovered models to city-level weekly mortality counts to estimate seasonal and long-term typhoid transmission. We examined seasonal transmission separately by city and aggregated by water source. We fit regression models to measure associations between long-term transmission and financial investments in water and sewer systems.ResultsTyphoid transmission peaked in late summer/early fall. Seasonality varied by water source, with the greatest variation occurring in cities with reservoirs. Historical $1 per capita ($25.80 in 2017) investments in construction and operation of water and sewer systems were associated with 8-53% decreases in typhoid transmission, while $1 increases in total value or debt accrued to maintain them were associated with 4-7% decreases.ConclusionOur findings aid in the understanding of typhoid transmission dynamics and potential impacts of water and sanitation improvements, and can inform cost-effectiveness analyses of interventions to reduce the typhoid burden.

Sign in / Sign up

Export Citation Format

Share Document