scholarly journals The parasitoid Aenasius arizonensis prefers its natural host but can parasitize a nonnatural host in the laboratory: an opportunity for control of a new invasive mealybug

2021 ◽  
Author(s):  
Jun Huang ◽  
Fuying Zhi ◽  
Juan Zhang ◽  
Xiaowei Li ◽  
Yaobin Lu
Keyword(s):  
Hind Tibia ◽  
Host Choice ◽  
Not Given ◽  
Emergence Time ◽  
Parasitism Rate ◽  
Phenacoccus Solenopsis ◽  
Offspring Fitness ◽  
Key Factor ◽  
Number Of Visits ◽  
Tibia Length

AbstractThe absence of natural enemies in newly invaded areas is a key factor in the successful invasion of alien species. Whether a specific parasitoid can be domesticated to attack a nonnatural host that has no reported parasitic enemies in invasive areas remains unclear. Here, we analyzed two invasive mealybugs (PSS-Phenacoccus solenopsis and PSI-Phenacoccus solani) and a specific parasitoid of P. solenopsis (Aenasius arizonensis) to verify this hypothesis under laboratory conditions. A. arizonensis preferred to parasitize PSS, but after 6 h, it also parasitized PSI female adults. The number of visits and parasitism rate was significantly higher for PSS than for PSI. However, the contact time was influenced by the natal host. The chemical volatiles emitted by the two hosts were different and may be an important factor for host choice. Offspring fitness, measured as emergence time, longevity, and hind tibia length, in those emerging from PSS was better in those emerging from PSI, but the emergence rate was higher in the latter. We supposed that A. arizonensis accepts and parasitizes low-quality hosts not because of an "incomplete" evaluation but because it may be more profitable to parasitize than not given circumstances; this may provide an opportunity for the control of a new invasive mealybug in the future.

scholarly journals Ability of Spalangia endius (Hymenoptera: Pteromalidae) to Parasitize Bactrocera dorsalis (Diptera: Tephritidae) after Switching Hosts

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 613
Author(s):  
Yuan Zheng ◽  
Zi-Wei Song ◽  
Yu-Ping Zhang ◽  
Dun-Song Li
Keyword(s):  
Bactrocera Dorsalis ◽  
Low Density ◽  
Type Ii ◽  
Emergence Time ◽  
Functional Responses ◽  
Parasitism Rate ◽  
Spalangia Endius ◽  
Pupal Parasite ◽  
Density Population

We studied the parasitism capacity of Spalangia endius as a pupal parasite of Bactocera dorsalis after switching hosts. We used pupae of B. dorsalis and M. domestica as the hosts and studied parasitism by S. endius in the laboratory. The parasitism capacities were compared at different host densities and different parasitoid ages. The two functional responses of S. endius fitted a Holling Type II equation. More M. domestica were parasitized than B. dorsalis at all the densities. The ability of S. endius to control M. domestica was α/Th (parasitism capacity) = 32.1950, which was much stronger than that of control B. dorsalis, which was α/Th = 4.7380. The parasitism rate of wasps that had parasitized B. dorsalis had decreased by the emergence time of parasitoids. These results suggest that the parasitoid-pest ratio should be 1:25 to maintain a relatively stable parasitism rate for control of B. dorsalis. The S. endius colony reared on M. domestica successfully controlled a low-density population of B. dorsalis in the lab. We provide evidence suggesting that the parasitism capacity of S. endius needs to be improved.

Effects ofHelicoverpa armigera(Noctuidae, Lepidoptera) host stages on some developmental parameters of the uniparental endoparasitoidMeteorus pulchricornis (Braconidae, Hymenoptera)

2007 ◽  
Vol 98 (2) ◽  
pp. 109-114 ◽  
Author(s):  
Liu Ya-hui ◽  
Li Bao-ping
Keyword(s):  
Adult Development ◽  
Helicoverpa Armigera ◽  
Growth And Development ◽  
Hind Tibia ◽  
Choice Test ◽  
Fitness Functions ◽  
Meteorus Pulchricornis ◽  
Helicoverpa Armígera ◽  
Parasitism Level ◽  
Tibia Length

AbstractA single choice test was performed to examine developmental strategies in the uniparental endoparasitoidMeteorus pulchricornisand its host, the cotton bollwormHelicoverpa armigera. The results support the dome-shaped model in which the fitness functions are ‘dome-shaped’ relative to size (and age) of host at parasitism. Older and, hence, larger host larvae were simply not better hosts for the developing parasitoids. Although parasitoid size (measured as cocoon weight and adult hind tibia length) was positively correlated with host instars at parasitism, parasitoids developing in larger hosts (L5and L6) suffered much higher mortality than conspecifics developing in smaller hosts (L2–L4). Furthermore, egg-to-adult development time inM. pulchricorniswas significantly longer in older host larvae (L4–L6) than in the younger. Performance ofM. pulchricornis, as indicated by fitness-related traits, strongly suggests that the L3host is the most suitable for survival, growth and development of the parasitoid, followed by both L2and L4hosts; whereas, L1, L5and L6are the least favourable hosts. The oviposition tendency ofM. pulchricornis, represented by parasitism level, was not perfectly consistent with the performance of the offspring; L2–L4hosts, although with the same parasitism level, had offspring parasitoids with differences in fitness-related performance. Larval development inHelicoverpa armigerawas usually suspended, but occasionally advanced, in the final instar.

scholarly journals Awareness and Knowledge of Portugal Residents about Natura 2000

2020 ◽  
Vol 12 (22) ◽  
pp. 9663
Author(s):  
Sofia S. Oliveira ◽  
Joana Pereira ◽  
Paulo Santos ◽  
Ruth Pereira
Keyword(s):  
Nature Conservation ◽  
Public Participation ◽  
Protected Areas ◽  
Wild Species ◽  
Natura 2000 ◽  
Recent Survey ◽  
Sharp Decline ◽  
Key Factor ◽  
Number Of Visits ◽  
Nationwide Implementation

Natura 2000 is the European Union’s key strategy to address the current sharp decline in biodiversity. However, according to a recent survey, most Europeans have never heard about it. The present study intended to further explore the perceptions of residents in Portugal about this network of protected areas through the nationwide implementation of a survey. Overall, 232 questionnaires were fulfilled, which showed that most respondents (n = 126, 54%) had never heard of Natura 2000. Furthermore, even the respondents who knew what Natura 2000 is were not well-informed about it. For instance, on average, they were only able to name 2.8 ± 2.2 sites within Portugal; plus, 66% (n = 65) could not correctly name any wild species that inhabited their favourite site. Surprisingly, literacy levels were not significantly correlated with the number of visits to the network (rs = 0.181, p = 0.082), and they were only weakly correlated with the frequency that the respondents engaged in ecological behaviours (rs = 0.277, p = 0.007). Overall, the current findings are in agreement with similar studies carried out in Poland that revealed that the population was poorly informed about this important network of protected areas. This scenario is especially worrisome, considering that public participation is regarded as a key factor for successful nature conservation initiatives.

Body size as an indicator of parasitoid quality in male and female Anagyrus kamali (Hymenoptera: Encyrtidae)

2001 ◽  
Vol 91 (5) ◽  
pp. 363-367 ◽  
Author(s):  
L.A. Sagarra ◽  
C. Vincent ◽  
R.K. Stewart
Keyword(s):  
Sex Ratio ◽  
Biological Control Agent ◽  
Hind Tibia ◽  
Control Agent ◽  
Large Male ◽  
Mating Preference ◽  
Small Female ◽  
Maconellicoccus Hirsutus ◽  
Anagyrus Kamali ◽  
Tibia Length

AbstractThe parasitoid Anagyrus kamali Moursi was recently introduced into the Caribbean as a biological control agent against the hibiscus mealybug, Maconellicoccus hirsutus Green. In the laboratory, parasitoid size, as measured by left hind tibia length, was positively correlated several indicators of the parasitoid‘s fitness: longevity, mating preference, fecundity, reproductive longevity, progeny emergence and sex-ratio. When fed ad libidum with honey drops, large male parasitoids lived significantly longer (29.1 ± 6.5 days) than small ones ± 5.7 days). Large females also lived significantly longer (35.4 ± 10 days) than small females (27.9 ± 9.6 days). Females showed no significant mating preference between large and small males. Lifetime fecundity was positively correlated with the size of adult females ranged from 37 ± 21 eggs for small females to 96 ± 43 eggs for large ones. The reproductive longevity, daily oviposition rate, and number of progeny were also higher among large parasitoids. The sex ratio of progeny from small female parasitoids was higher (0.76 ± than that of large individuals (0.47 ± 0.18).

scholarly journals VARIABLES RELACIONADAS CON EL NÚMERO Y ELECCIÓN DE LAS REDES SOCIALES DE LOS HOTELES ANDALUCES DE 4 Y 5 ESTRELLAS

2020 ◽  
pp. 93-111
Author(s):  
Inmaculada Rabadán-Martín ◽  
Nuria Padilla-Garrido ◽  
Francisco Aguado-Correa
Keyword(s):  
Social Networks ◽  
Social Network ◽  
Network Management ◽  
Redes Sociales ◽  
Establishment Size ◽  
The Social ◽  
Key Factor ◽  
Number Of Visits ◽  
Potential Factors ◽  
Online Reputation

La gestión de las redes sociales se ha convertido en un factor clave para el turismo. Los contenidos generados en las mismas pueden condicionar la elección por parte de los turistas, la reputación online, las ventas, e incluso la supervivencia de un establecimiento hotelero. A través del estudio de 503 hoteles andaluces de 4 y 5 estrellas, nuestro trabajo analiza la totalidad de redes sociales presentes en sus páginas web oficiales, así como los posibles factores (número de estrellas, modalidad, antigüedad, tamaño y pertenencia a cadena) que pueden influir en el número y la elección de estas.   Social network management has become a key factor in developing tourism. Content generated on social networks can influence tourist choices, online reputation, sales and the very survival of the hotel establishment. In a study of 503 four- and five-star hotels in Andalusia, we analysed all the social networks used on their official websites to attract customers, and the potential factors (number of stars, modality, age of the establishment, size, chain hotel or otherwise) that could influence the number of visits and choice of destination.

scholarly journals The Effects of Temperature on the Development, Morphology, and Fecundity of Aenasius bambawalei (=Aenasius arizonensis)

Insects ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 833
Author(s):  
Juan Zhang ◽  
Yayuan Tang ◽  
Jun Huang
Keyword(s):  
High Temperature ◽  
Natural Enemies ◽  
Morphological Changes ◽  
Insect Pest ◽  
Hind Tibia ◽  
Developmental Rate ◽  
Female Offspring ◽  
Developmental Duration ◽  
Phenacoccus Solenopsis ◽  
Different Temperatures

The effects of high temperature on the developmental, morphological, and fecundity characteristics of insects, including biological invaders and their accompanying natural enemies, are clear. Phenacoccus solenopsis (Homoptera: Pseudococcidae) is an aggressive invasive insect pest worldwide. Aenasius bambawalei (=Aenasius arizonensis Girault) (Hymenoptera: Encyrtidae) is a predominant accompanying parasitoid of this mealybug. Our previous studies showed that temperature change induced an increase in the female offspring ratio of A. bambawalei. However, whether this increase is the result of a shortened or enhanced development period of the reproductive systems of A. bambawalei remains unknown. Here, we compared the pupal development, hind tibia of female adults, and fecundity of A. bambawalei under different temperatures to clarify the development and morphological changes induced by high temperature and to better understand its potential as an accompanying natural enemy. Our results showed that, at a high temperature (36 °C), the pupal developmental duration of A. bambawalei was only 0.80 times that of the control, and the length of the hind tibia was 1.16 times that of the control. Moreover, high temperature accelerated the developmental rate of gonads and increased the numbers of eggs and sperm. These results indicated that experimental warming shortened the pupal developmental duration, altered the hind tibia length of female adults, and facilitated the fecundity of A. bambawalei. These findings will help to understand the adaptation mechanisms of accompanying natural enemies. Furthermore, these findings will help to make use of this behavior to effectively control invasive pests.

scholarly journals Attendance and Perceived Constraints to Attendance at Zoological Gardens during the Spring 2020 COVID-19 Re-Opening: The Czechia Case

2021 ◽  
Vol 2 (2) ◽  
pp. 234-249
Author(s):  
Lukáš Nekolný ◽  
Dana Fialová
Keyword(s):  
Surface Area ◽  
Questionnaire Survey ◽  
Online Communication ◽  
Communication Channels ◽  
Daily Maximum ◽  
Central European ◽  
Key Factor ◽  
Specific Factors ◽  
Number Of Visits ◽  
Perceived Constraints

Zoos are one of the most visited tourist and leisure attractions. After all the important Central-European zoos closed in the spring of 2020 due to the COVID-19 pandemic, a few weeks later they started to re-open. The main goal of this article is to evaluate how the number of visits developed after the first zoo re-openings and what specific factors limited attendances the most after the reopening, using the example of Czech zoos in May and June 2020. In addition to the information available on zoos’ online communication channels, the authors’ questionnaire survey data and attendance data provided by the zoos were used. The results indicate that the attendance was reduced the most by the obligation to buy tickets online, by the closure of state borders, and by a low limit on daily maximum number of visitors allowed. Different approaches to restricting zoos’ capacity are discussed and the use of the maximum number of people by surface area of visitor routes at one time to limit attendance is recommended. In the future, this could be a key factor for sustainability of many zoos.

Attachment of oral bacteria to titanium surfaces: An SEM study

1994 ◽  
Vol 52 ◽  
pp. 468-469
Author(s):  
J. E. Laffoon ◽  
R. L. Anderson ◽  
J. C. Keller ◽  
C. D. Wu-Yuan
Keyword(s):  
Technical Problem ◽  
Titanium Implant ◽  
Oral Bacteria ◽  
Bacterial Cells ◽  
Thin Sections ◽  
Surface Ultrastructure ◽  
Sem Study ◽  
Key Factor ◽  
Titanium Surfaces

Titanium (Ti) dental implants have been used widely for many years. Long term implant failures are related, in part, to the development of peri-implantitis frequently associated with bacteria. Bacterial adherence and colonization have been considered a key factor in the pathogenesis of many biomaterial based infections. Without the initial attachment of oral bacteria to Ti-implant surfaces, subsequent polymicrobial accumulation and colonization leading to peri-implant disease cannot occur. The overall goal of this study is to examine the implant-oral bacterial interfaces and gain a greater understanding of their attachment characteristics and mechanisms. Since the detailed cell surface ultrastructure involved in attachment is only discernible at the electron microscopy level, the study is complicated by the technical problem of obtaining titanium implant and attached bacterial cells in the same ultra-thin sections. In this study, a technique was developed to facilitate the study of Ti implant-bacteria interface.Discs of polymerized Spurr’s resin (12 mm x 5 mm) were formed to a thickness of approximately 3 mm using an EM block holder (Fig. 1). Titanium was then deposited by vacuum deposition to a film thickness of 300Å (Fig. 2).

Forum: Morphological Awareness as a Key Factor in Language-Literacy Success for Academic Achievement

2020 ◽  
Vol 51 (3) ◽  
pp. 509-513
Author(s):  
Ashley Bourque Meaux ◽  
Julie A. Wolter ◽  
Ginger G. Collins
Keyword(s):  
Academic Achievement ◽  
Academic Success ◽  
Literacy Development ◽  
Morphological Awareness ◽  
Language And Literacy ◽  
Speech Language Pathologists ◽  
School Based ◽  
Literacy Success ◽  
Key Factor ◽  
Language And Literacy Development

Purpose This article introduces the Language, Speech, and Hearing Services in Schools Forum: Morphological Awareness as a Key Factor in Language-Literacy Success for Academic Achievement. The goal of this forum is to relate the influence morphological awareness (MA) has on overall language and literacy development with morphology acting as the “binding agent” between orthography, phonology, and semantics ( Perfetti, 2007 ) in assessment and intervention for school-aged children. Method This introduction provides a foundation for MA development and explores the influence MA has over the course of school-aged language and literacy development. Through summaries of the 11 articles in this forum, school-based speech-language pathologists will be able to convey the importance of MA to promote successful educational outcomes for kindergarten to adolescent students. The forum explores researcher-developed assessments used to help identify MA skill level in first- through eighth-grade students at risk for literacy failure to support instructional needs. The forum also provides school-based speech-language pathologists with details to design and implement MA interventions to support academic success for school-aged students with varying speech-language needs (e.g., dual language emersion, vocabulary development, reading comprehension) using various service delivery models (e.g., small group, classroom-based, intensive summer camps). Conclusion MA is effective in facilitating language and literacy development and as such can be an ideally focused on using multilinguistic approaches for assessment and intervention. The articles in this issue highlight the importance in assessment measures and intervention approaches that focus on students' MA to improve overall academic success in children of all ages and abilities.

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