Study of Abiotic and Biotic Parameters Affecting the Abundance of Mosquito Larvae (Diptera: Culicidae) in the Region of Fez (Morocco)

Mosquitoes cause significant human health issues. However, very few studies have attempted to examine the question of how abiotic and biotic factors affect the abundance of Culicidae in the larval habitat. The objective of this study was to analyze the influence of biotic and abiotic factors on the increase of the most common mosquito species in the Fez region (Central Morocco). Larvae mosquitoes were sampled by standard dipping technique in four different types of macrohabitats, between November 2015 and November 2016. Each mosquito specimen was morphologically identified by the Moroccan Culicidae key and the Brunhes key. The analysis was done using R analysis software. We collected a total of 772 mosquito larvae belonging to nine different species, five of which are considered of medical interest. Culex pipiens (Linnaeus, 1758), known as the major vector in the transmission of West Nile virus fever (WNV), was the most common species of all mosquito larvae collected. The results of Poisson regression analysis showed that factors such as the presence of green filamentous algae, vegetation cover, and debris were found to be positively significant in the distribution of the genus Culex. However, there was insufficient evidence to determine the parameters that are capable of estimating the abundance of Anopheles. The findings have also estimated that biotic and abiotic factors can lead to significant variation in the abundance of Culex perexiguus (Theobald, 1903), Culex theileri (Theobald, 1903), and Culex pipiens (Linnaeus, 1758). Identifying the priority parameters governing the proliferation of mosquitoes in the region of Fez can be one of the key elements for better vector control.

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Delivery Methods for RNAi in Mosquito Larvae

Journal of Insect Science ◽

10.1093/jisesa/ieaa074 ◽

2020 ◽

Vol 20 (4) ◽

Author(s):

Kashif Munawar ◽

Azzam M Alahmed ◽

Sayed M S Khalil

Keyword(s):

Mosquito Control ◽

Mosquito Species ◽

Main Tool ◽

Field Application ◽

World Population ◽

Mosquito Larvae ◽

Health Issues ◽

Delivery Methods ◽

Resistance Development ◽

The World

Abstract Mosquito-transmitted diseases pose a threat for a great portion of the world population. Chemical insecticides are the main tool for mosquito control. Heavy dependence on chemicals created several problems such as resistance development in many mosquito species, environmental effects, and human health issues. Other tools for mosquito control were developed and used in some parts of the world. Ribonucleic acid interference (RNAi) is a reverse genetic mechanism that was recently introduced as a new tool for pest control. Regarding mosquito, RNAi was used to study gene function and to discover genes that can be used as targets for control purposes. Several delivery methods are used to induce RNAi in mosquito larvae. Some methods such as injection and soaking are used routinely in RNAi research but have no application in the field. Other methods such as nanoparticles and microbes have some characteristics that make them good candidates for field application. In this report, we will focus on delivery methods for RNAi in mosquito larvae and will give examples for each method.

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Evaluation of species composition and seasonal dynamics of mosquito larvae in the Košice Basin during 2010 and 2011

Biologia ◽

10.2478/s11756-013-0150-1 ◽

2013 ◽

Vol 68 (2) ◽

Author(s):

Eva Bocková ◽

Alica Kočišová ◽

Helena Hlavatá

Keyword(s):

Species Diversity ◽

Species Composition ◽

Seasonal Dynamics ◽

Culex Pipiens ◽

Mosquito Species ◽

Mosquito Larvae ◽

Aedes Vexans ◽

Anopheles Maculipennis

AbstractIn six sites in the Košice Basin we collected 17,520 larvae of 15 mosquito species during the seasons (April–August) of 2010 and 2011. They were: Aedes vexans (Meigen, 1830), Ae. cinereus (Meigen, 1818) [or Ae. rossicus (Dolbeskin, Gorickaja & Mitrofanova, 1930], Ochlerotatus geniculatus (Olivier, 1791), Oc. refiki (Medschid, 1928), Oc. rusticus (Rossi, 1790), Oc. sticticus (Meigen, 1838), Oc. punctor (Kirby, 1837), Oc. cataphylla (Dyar, 1916), Oc. cantans (Meigen, 1818)[or Oc. annulipes (Meigen, 1830)], Oc. communis (De Geer, 1776), Oc. flavescens (Müller, 1764), Oc. leucomelas (Meigen, 1804), Culiseta annulata (Schrank, 1776), Culex pipiens (L., 1758) [or Cx. torrentium (Martini, 1925)] and Anopheles maculipennis s.l. The objective of the present research was to identify the mosquito larvae species diversity and compare their distribution and density in urban and suburban localities of the monitored territory.

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Biodiversity of Social Wasps (Hymenoptera: Vespidae) at Altitudes Above 1600 Meters in the Parque Estadual da Serra do Papagaio, State of Minas Gerais, Brazil

EntomoBrasilis ◽

10.12741/ebrasilis.v8i3.519 ◽

2015 ◽

Vol 8 (3) ◽

pp. 174-179 ◽

Cited By ~ 2

Author(s):

Marcos Magalhães de Souza ◽

Heloina Nathalliê Mariano da Silva ◽

João Batista Dallo ◽

Lizandra de Fátima Martins ◽

Lucas Rocha Milani ◽

...

Keyword(s):

Solar Radiation ◽

High Altitude ◽

Abiotic Factors ◽

Common Species ◽

Social Wasps ◽

Minas Gerais ◽

Ecological Role ◽

Biotic And Abiotic Factors ◽

Campos De Altitude ◽

Dark Coloration

The Parque Estadual da Serra do Papagaio is the largest area of natural preservation in the south of Minas Gerais, with areas of Floresta Atlantica, Floresta de Araucaria and Campos de Altitude. Although this is an area of biological importance, there are many groups that have not yet been studied there: for example social wasps, which are insects belonging to order Hymenoptera, family Vespidae, which play an important ecological role in different ecosystems. This study was carried out in the aforementioned natural preservation area at altitudes between 1600 and 2200 m in 20 days of sampling between July of 2013 and April of 2014, using active searches and attractive traps to record species. Twenty two species of social wasps were sampled, distributed in seven genera. This number is small compared to counts from other studies in this state, which is probably due to the high altitude of this area. There was a predominance of nests with protective casings in the most common species recorded, and the most populous species was Polybia fastidiosuscula Saussure, a finding that can be explained by the superior thermoregulation afforded by the nest casing. Two other common species were Mischocyttarus drewseni Saussure, and Mischocyttarus rotundicolis (Cameron), which have nests without casings; however, these species have dark coloration, as does the substrate used for nesting, and can therefore enhance retention of solar radiation; nevertheless, other biotic and abiotic factors could be involved.Biodiversidade de Vespas Sociais (Hymenoptera: Vespidae) em Áreas de Altitude Acima de 1600 Metros do Parque Estadual da Serra do Papagaio, Estado de Minas Gerais, BrasilResumo. O Parque Estadual da Serra do Papagaio é a maior Unidade de Conservação do sul de Minas Gerais, com áreas de Mata Atlântica, floresta de Araucária e Campos de Altitude. Apesar da importância biológica da área, muitos grupos animais não foram estudados, como as vespas sociais, insetos que pertencem à ordem Hymenoptera, família Vespidae, e que desempenham importante papel ecológico em diferentes ecossistemas. O estudo foi conduzido nessa Unidade de Conservação em altitudes entre 1600 a 2200 m, no período de julho de 2013 a abril de 2014, durante vinte dias de amostragem, utilizando busca ativa e armadilhas atrativas para registro das espécies. Foram amostradas 22 espécies de vespas sociais distribuídas em sete gêneros. Número menor em relação a outros estudos do estado, o que, provavelmente, foi ocasionado pela elevada altitude. Houve uma predominância de ninhos com invólucro protetor e a espécie mais frequente foi Polybia fastidiosuscula Saussure, o que pode ser explicado pela melhor regulação térmica obtida pelo invólucro. Outras duas espécies frequentes foram Mischocyttarus drewseni Saussure e Mischocyttarus rotundicolis (Cameron) que possuem ninhos sem invólucro, porém essas espécies possuem coloração escura, assim como o substrato utilizado para nidificação e isso poderia reter melhor a radiação solar. Contudo outros fatores bióticos e abióticos podem estar envolvidos.

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Seasonal dynamics of mosquitoes (Diptera: Culicidae) in Osijek (Croatia) for the period 1995–2004

Biologia ◽

10.2478/s11756-009-0138-z ◽

2009 ◽

Vol 64 (4) ◽

Cited By ~ 6

Author(s):

Mirta Bogojević ◽

Enrih Merdić ◽

Nataša Turić ◽

Željka Jeličić ◽

Željko Zahirović ◽

...

Keyword(s):

Culex Pipiens ◽

Mosquito Species ◽

Common Species ◽

Significant Information ◽

Anopheles Maculipennis Complex ◽

Anopheles Maculipennis ◽

Seasonal Population ◽

Seasonal Population Dynamics ◽

Forest Habitats ◽

Maculipennis Complex

AbstractThe ten year research (1995–2004) of adult mosquitoes in the area of Osijek by dry ice baited CDC traps has provided significant information on mosquito species, species prevalence, their dynamics and seasonal activity. A total of 207,136 adult mosquitoes comprising twenty species belonging to the following genera: Anopheles, Ochlerotatus, Aedes, Culex, Coquillettidia, Culiseta and Uranotaenia were collected. The seven most common species collected during this study were: Aedes vexans (75.6%), Ochlerotatus sticticus (13.3%), Culex pipiens complex (5.9%), Anopheles maculipennis complex (1.9%), Oc. cantans (0.9%), Oc. caspius (0.6%) and Oc. excrucians (0.6%). The temporal changes in the relative abundance of the twenty mosquito species in the Osijek area were reflected in three peaks: in May, July and September. Seasonal population dynamics differed between years and between mosquito species in relation to wetland, urban and forest habitats and was influenced by water level of the Drava and the Danube rivers.

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Species composition and seasonal dynamics of mosquitoes (Diptera: Culicidae) in flooded areas of Vojvodina, Serbia

Archives of Biological Sciences ◽

10.2298/abs1004193v ◽

2010 ◽

Vol 62 (4) ◽

pp. 1193-1206 ◽

Cited By ~ 3

Author(s):

A. Vujic ◽

A. Stefanovic ◽

I. Dragicevic ◽

T. Matijevic ◽

L. Pejcic ◽

...

Keyword(s):

Species Composition ◽

Culex Pipiens ◽

Mosquito Species ◽

Common Species ◽

Seasonal Activity ◽

Anopheles Maculipennis ◽

Seasonal Population ◽

Seasonal Population Dynamics ◽

Flooded Areas ◽

Forest Habitats

Three years of sampling (2007-2009) of adult mosquitoes in the area of Vojvodina (Serbia) by dry ice baited CDC traps has provided information on mosquito species composition, prevalence and seasonal activity. A total of 58,247 adult mosquitoes were collected comprising twenty species belonging to the following genera: Anopheles Meigen (Diptera: Culicidae), Aedes Meigen, Culex L, Culiseta Felt and Mansonia Blanchard. The seven most common species collected during this study were: Culex pipiens L. complex (35.6%), Aedes vexans (Meigen) (33.4%), Aedes sticticus (Meigen) (15.2%), Anopheles maculipennis Meigen complex (4%), Mansonia richiardii (Ficalbi) (3.8%), Aedes cinereus Meigen (3.6%), Aedes pulchritarsis (Rondani) (3%) which made up 98% of all specimens. Seasonal population dynamics differed between years and between mosquito species in relation to wetland, urban and forest habitats, and was primarily influenced by the water level of the Danube, Sava and Tisa rivers, precipitation and temperature.

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Naturally Occurring Microbiota Associated with Mosquito Breeding Habitats and Their Effects on Mosquito Larvae

BioMed Research International ◽

10.1155/2020/4065315 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

H. A. K. Ranasinghe ◽

L. D. Amarasinghe

Keyword(s):

Abiotic Factors ◽

Mosquito Species ◽

Breeding Habitat ◽

Larval Abundance ◽

Mosquito Larvae ◽

Natural Habitats ◽

Individual Fitness ◽

Naturally Occurring ◽

Breeding Habitats ◽

Mosquito Breeding

Immature mosquitoes are aquatic, and their distribution, abundance, and individual fitness in a particular breeding habitat are known to be dependent on mainly three factors: biotic factors, abiotic factors, and their interaction between each other and with other associated taxa. Mosquito breeding habitats harbor a diversified naturally occurring microbiota assemblage, and the biota have different types of interactions with mosquito larvae in those habitats. Those interactions may include parasitism, pathogenism, predation, and competition which cause the mortality of larvae, natural reduction of larval abundance, or alterations in their growth. Many microbiota species serve as food items for mosquito larvae, and there are also some indigestible or toxic phytoplanktons to larvae. However, when there is coexistence or mutualism of different mosquito species along with associated microbiota, they form a community sharing the habitat requirements. With the available literature, it is evident that the abundance of mosquito larvae is related to the densities of associated microbiota and their composition in that particular breeding habitat. Potential antagonist microbiota which are naturally occurring in mosquito breeding habitats could be used in integrated vector control approaches, and this method rises as an ecofriendly approach in controlling larvae in natural habitats themselves. To date, this aspect has received less attention; only a limited number of species of microbiota inhabiting mosquito breeding habitats have been recorded, and detailed studies on microbiota assemblage in relation to diverse vector mosquito breeding habitats and their association with mosquito larvae are few. Therefore, future studies on this important ecological aspect are encouraged. Such studies may help to identify field characteristic agents that can serve as mosquito controlling candidates in their natural habitats themselves.

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Decline of European Beech in Austria: Involvement of Phytophthora spp. and Contributing Biotic and Abiotic Factors

Forests ◽

10.3390/f11080895 ◽

2020 ◽

Vol 11 (8) ◽

pp. 895 ◽

Cited By ~ 2

Author(s):

Tamara Corcobado ◽

Thomas L. Cech ◽

Martin Brandstetter ◽

Andreas Daxer ◽

Christine Hüttler ◽

...

Keyword(s):

Fine Root ◽

Abiotic Factors ◽

European Beech ◽

Pathogenic Fungi ◽

Common Species ◽

Beech Forest ◽

Phytophthora Species ◽

Root Tips ◽

Collar Rot ◽

Biotic And Abiotic Factors

A severe decline and dieback of European beech (Fagus sylvatica L.) stands have been observed in Austria in recent decades. From 2008 to 2010, the distribution and diversity of Phytophthora species and pathogenic fungi and pests were surveyed in 34 beech forest stands in Lower Austria, and analyses performed to assess the relationships between Phytophthora presence and various parameters, i.e. root condition, crown damage, ectomycorrhizal abundance and site conditions. In total, 6464 trees were surveyed, and Phytophthora-associated collar rot and aerial bark cankers were detected on 133 trees (2.1%) in 25 stands (73.5%). Isolations tests were performed from 103 trees in 27 stands and seven Phytophthora species were isolated from bleeding bark cankers and/or from the rhizosphere soil of 49 trees (47.6%) in 25 stands (92.6%). The most common species were P. ×cambivora (16 stands) followed by P. plurivora (eight stands) and P. cactorum (four stands), while P. gonapodyides, P. syringae, P. psychrophila and P. tubulina were each found in only one stand. Geological substrate had a significant effect on the distribution of P. ×cambivora and P. plurivora while P. cactorum showed no site preferences. In addition, 21 fungal species were identified on beech bark, of which 19 and five species were associated with collar rot and aerial bark cankers, respectively. Four tested fine root parameters showed differences between declining and non-declining beech trees in both Phytophthora-infested and Phytophthora-free stands. In both stand categories, ectomycorrhizal frequency of fine root tips was significantly higher in non-declining than in declining trees. This study confirmed the involvement of Phytophthora species in European beech decline and underlines the need of more research on the root condition of beech stands and other biotic and abiotic factors interacting with Phytophthora infections or causing beech decline in absence of Phytophthora.

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Preliminary studies for the attract-and-kill strategy against Culex pipiens

ENTOMOLOGIA HELLENICA ◽

10.12681/eh.11611 ◽

2017 ◽

Vol 17 ◽

pp. 3 ◽

Cited By ~ 3

Author(s):

E. Kioulos ◽

G. Koliopoulos ◽

E. A. Couladouros ◽

A. Michaelakis

Keyword(s):

Bacillus Thuringiensis ◽

Growth Regulator ◽

Culex Pipiens ◽

Mosquito Species ◽

Insect Growth Regulator ◽

Mosquito Larvae ◽

Synthetic Pheromone ◽

Attract And Kill ◽

Gravid Females ◽

Microbial Agent

The attract-and-kill strategy requires an intelligent and an efficient combination of an attractant and a killing agent such as a pheromone and an insecticide respectively. The production of the synthetic oviposition pheromone of the mosquito species Culex quinquefasciatus (Diptera: Culicidae) was already achieved and its combination with three different insecticides were tested. Furthermore three larvicides, an insect growth regulator (pyriproxyfen), an organophosphate (temephos) and a microbial (Bacillus thuringiensis subsp. israelensis) were tested in the laboratory against Culex pipiens biotype molestus (Diptera: Culicidae) as agents that can keep water free from mosquito larvae. Larvicidal activity, over a 50-day period, revealed good results primary for temephos and secondary for pyriproxyfen. Temephos killed all the hatched larvae (100%) while pyriproxyfen was effective the first five days (>90%) and for the following days mortality was in a rate between 60 and 80%. The results from oviposition bioassays revealed that except temephos all the tested larvicidals repel gravid females of laying eggs for the first two days. However, when synthetic pheromone is combined with the three larvicidals, temephos and microbial agent followed the same attractant pattern as synthetic pheromone independently.

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