scholarly journals Oviposition Behavior of Culex tarsalis (Diptera: Culicidae) Responding to Semiochemicals Associated with the Western Mosquitofish, Gambusia affinis (Cyprinodontiformes: Poecilliidae)

2019 ◽  
Vol 57 (2) ◽  
pp. 343-352 ◽  
Author(s):  
Adena M Why ◽  
William E Walton
Keyword(s):  
Tap Water ◽  
Oviposition Behavior ◽  
Pond Water ◽  
Gambusia Affinis ◽  
Egg Laying ◽  
Culex Tarsalis ◽  
Mosquito Oviposition ◽  
Natural Density ◽  
Gravid Mosquitoes ◽  
Laboratory Bioassays

Abstract Considerable previous research has focused on predator-associated semiochemicals and how they affect mosquito oviposition behavior. However, most of this work has been done without taking into consideration either the natural density of the predators or how other semiochemicals in aquatic environments might affect the responses of gravid mosquitoes. The influence of mosquitofish density, source water (tap vs pond), presence of freshly laid egg rafts, and removal of a putative source of semiochemicals (bacteria) on oviposition by Culex tarsalis Coquillett (Diptera: Culicidae) was studied in laboratory bioassays. Culex tarsalis females were deterred from laying egg rafts on water that contained semiochemicals associated with Gambusia affinis (Baird & Girard), but this deterrence was not strongly associated with the density of fish used to condition aged tap water. The number of egg rafts laid onto Gambusia-exudate water made with either tap water (density < 1 fish per liter) or pond water was typically ≥ 50% of that onto water that did not house mosquitofish. Gravid mosquitoes tested individually did not reduce oviposition onto Gambusia-exudate water as compared to controls. Likewise, oviposition by females with ablated wings did not differ significantly between Gambusia-exudate water and controls. Oviposition onto filter-sterilized Gambusia-exudate water was reduced relative to unfiltered water, suggesting that semiochemicals deterring egg-laying were still present after bacteria were removed. Taken together, these findings suggest that the responses of gravid Cx. tarsalis to chemicals from habitats containing mosquitofish are complex and the origin of the semiochemicals present in the Gambusia-exudate water needs to be elucidated.

Identification of Chemicals Associated Gambusia affinis (Cyprinodontiformes: Poeciliidae), and Their Effect on Oviposition Behavior of Culex tarsalis (Diptera: Culicidae) in the Laboratory

2021 ◽  
Author(s):  
Adena M Why ◽  
Dong-Hwan Choe ◽  
William E Walton
Keyword(s):  
Volatile Compounds ◽  
Oviposition Behavior ◽  
Dimethyl Disulfide ◽  
Ring Structure ◽  
Gambusia Affinis ◽  
Culex Tarsalis ◽  
Waste Products ◽  
Treated Water ◽  
Low Concentrations ◽  
Volatile Chemical Compounds

Abstract The western mosquitofish, Gambusia affinis (Baird & Girard), has been used worldwide for the control of larval mosquitoes for more than 100 yr. We found that the western encephalitis mosquito, Culex tarsalis Coquillett (Diptera: Culicidae), can detect the presence of G. affinis in oviposition sites based on associated chemicals, leading to a decrease in the number of egg rafts laid. Three volatile chemical compounds were identified in the headspace above the water where G. affinis had been held for 24 h. Oviposition bioassays conducted using standards of the volatile compounds identified (dimethyl disulfide [DMDS], dimethyl trisulfide [DMTS], and S-methyl methanethiosulphonate) found that females reduced oviposition only when low concentrations of DMTS were present, but this response was not consistent across all trials and concentrations tested. DMDS, DMTS, and S-methyl methanethiosulphonate are known bacterial metabolic waste products and may be the source of the compounds. Two nonvolatile compounds of interest were found to be present in the Gambusia-exudate water. After tasting Cx. tarsalis were deterred from ovipositing onto Gambusia-treated water from which the bacteria had been removed by filtration, indicating that the kairomone may consist of nonvolatile compound(s). One of the nonvolatile compounds isolated from the Gambusia-treated water has a benzene ring structure similar to that of cholesterol but the structure of the two nonvolatile deterrents remains to be fully characterized. Our research shows that three volatile compounds and two nonvolatile compounds are present in water associated with G. affinis (Poeciliidae: Gambusia) and affect the oviposition behavior of Cx. tarsalis in laboratory bioassays.

scholarly journals Laboratory Evaluation of Oviposition Behavior of Field Collected Aedes Mosquitoes

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Subrat K. Panigrahi ◽  
Tapan K. Barik ◽  
Satyabrata Mohanty ◽  
Niraj Kanti Tripathy
Keyword(s):  
Tap Water ◽  
Oviposition Behavior ◽  
Oviposition Preference ◽  
Egg Laying ◽  
Laboratory Evaluation ◽  
Distilled Water ◽  
Wild Female ◽  
Aedes Mosquitoes ◽  
Nacl Concentration ◽  
Different Sources

Wild female Aedes aegypti and Ae. albopictus were allowed to lay eggs in (i) ovitraps with different concentrations of NaCl, (ii) different coloured ovistrips, (iii) water from different sources, (iv) larva holding water, and different sized ovitraps for oviposition preference. Oviposition cycle was also studied in different photoperiod regimens. The number of eggs laid was observed to gradually decrease with increase in NaCl concentration in both the species. Experiments were conducted to determine egg laying preference for any specific colour of the ovistrip and black ovistrip was found to be most preferred by both the species. For oviposition preference, eight water samples collected from different sources were used and it was observed that the maximum number of eggs was laid in ovitraps containing distilled water followed by tap water. In addition, Aedes mosquitoes laid more number of eggs in ovitraps containing larval holding water than ovitraps containing distilled water. Further, both the species did not lay any egg in the smallest used ovitrap although the number of eggs was maximally deposited in the largest ovitrap used. In the present studies, both the Aedes species laid the maximum number of eggs in the 4th quarter of the light period with normal 12 h light and dark phases (LD 12 : 12).

logjam Encodes a Predicted EMP24/GP25 Protein That Is Required for Drosophila Oviposition Behavior

Genetics ◽  
2003 ◽  
Vol 164 (1) ◽  
pp. 173-186
Author(s):  
Ginger E Carney ◽  
Barbara J Taylor
Keyword(s):  
Intracellular Trafficking ◽  
Oviposition Behavior ◽  
Egg Laying ◽  
P Element ◽  
Female Reproduction ◽  
Multiple Functions ◽  
Cytoplasmic Vesicles ◽  
Egg Chambers ◽  
Low Levels ◽  
Overlapping Transcripts

Abstract A newly characterized Drosophila melanogaster gene, logjam (loj), functions in female reproduction by modulating oviposition behavior. The locus encodes at least six overlapping transcripts with unique 5′ ends. P-element mutants that express very low levels of loj transcripts are unable to oviposit mature eggs. This phenotype can be rescued by the introduction of a transgene expressing the most abundant loj transcript. As for many genes that specify behavioral outputs, loj is present in the adult central nervous system (CNS). Interestingly, it is also observed in vitellogenic egg chambers, suggesting that there may be multiple functions for this gene in egg-laying behavior. loj encodes a predicted protein with homology to the EMP24/GP25 transmembrane components of cytoplasmic vesicles and likely functions in intracellular trafficking.

scholarly journals Identifying the Biological Characteristics Associated with Oviposition Behavior of Tea Leafhopper Empoasca onukii Matsuda Using the Blue Light Detection Method

Insects ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 707
Author(s):  
Qi Yao ◽  
Huining Zhang ◽  
Long Jiao ◽  
Xiaoming Cai ◽  
Manqun Wang ◽  
...  
Keyword(s):  
Blue Light ◽  
Detection Method ◽  
Oviposition Behavior ◽  
Egg Laying ◽  
Biological Characteristics ◽  
Light Detection ◽  
Tea Plantations ◽  
Egg Density ◽  
Theoretical Evidence ◽  
Proven Method

Tea leafhopper (Empoasca onukii Matsuda) is amongst the key pests in tea plantations around the East Asian region. Stereomicroscopy is a conventional method used for detecting tea leafhopper eggs by dissecting the tender tissues. However, there is a need for a faster and more efficient method to directly observe and investigate intact eggs within tea shoots. The absence of a proven method limits research efforts for determining the oviposition behavior of E. onukii. Herein, we applied the blue light detection method (BLDM), a technique recently developed for other species, in order to detect E. onukii eggs directly and non-destructively within the tender shoot. In addition, we compared BLDM against the traditional stereomicroscope detection method (SMDM) for four tea cultivars. Notably, our results revealed that BLDM was precise and effective in measuring the egg laying quantity of E. onukii on intact tea shoots. Neither tea cultivars nor egg density in the tender shoot significantly affected the accuracy of BLDM. Furthermore, biological characteristics that have rarely been reported previously for E. onukii were investigated using the BLDM, including zygote duration, ovipositional rhythm, egg distribution within the tender shoot, and in different leaf positions, numbers of eggs laid by a single female daily, and laid by the entire generation. Therefore, these findings provide insights into the basic and theoretical evidence for the strategy and mechanism associated with the oviposition behavior of E. onukii.

Effects of crude aqueous extracts of indigenous pesticidal plants on the ladybird beetle, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae)

2018 ◽  
Vol 38 (02) ◽  
pp. 159-167
Author(s):  
E. Mazhawidza ◽  
B. M. Mvumi ◽  
U. Mazarura
Keyword(s):  
Plant Extracts ◽  
Tap Water ◽  
Datura Stramonium ◽  
Negative Control ◽  
Aqueous Extracts ◽  
Ladybird Beetle ◽  
Post Exposure ◽  
Application Rates ◽  
Hippodamia Variegata ◽  
Laboratory Bioassays

AbstractEffects of pesticidal plant extracts on non-targeted species are rare. Direct topical and residual sprays of crude aqueous extracts of three pesticidal plants: Datura stramonium L. Bobgunnia madagascariensis Kirkbr. & Wiersema and Solanum delagoense L. were assessed in laboratory bioassays and on-station experiments against the ladybird beetle, Hippodamia variegata (Goeze). The plants are routinely used by smallholder vegetable farmers to control aphids, Brevicoryne brassicae L. attacking rape, Brassica napus L. The crude extracts of D. stramonium fresh leaves, S. delagoense fresh fruits and B. madagascariensis dried pods, were applied separately at 5, 10, 15, 20 and 25% w/v under laboratory conditions. Application rates of 20% and 25% w/v of the plant extracts were further evaluated on-station. Negative (tap water) and positive (dimethoate® (36% E.C)) controls were included for comparison. The mortality of H. variegata was recorded 24, 48 and 72 h post-exposure. In on-station experiments, treatments were applied fortnightly and live H. variegata adults were counted at 1, 7 and 14 days post-application. Mortality of H. variegata in laboratory bioassays increased with increase in post-exposure time and B. madagascariensis (25% w/v) caused the highest mortality. Based on LD50 values, B. madagascariensis extracts were most toxic (LD50, 30% w/v) followed by D. stramonium (LD50, 34% w/v) and S. delagoense (LD50, 49% w/v) 24 h post-application. In on-station experiments, the synthetic chemical significantly lowered (P < 0.05) H. variegata numbers compared to the negative control and plant extracts. The results showed that D. stramonium and S. delagoense extracts at the application rates used in the study were relatively safer to H. variegata than B. madagascariensis (25% w/v); hence, the former two plants can be included in integrated pest management programmes.

scholarly journals RNAi-based demonstration of direct link between specific odorant receptors and mosquito oviposition behavior

2013 ◽  
Vol 43 (10) ◽  
pp. 916-923 ◽  
Author(s):  
Fen Zhu ◽  
Pingxi Xu ◽  
Rosângela M.R. Barbosa ◽  
Young-Moo Choo ◽  
Walter S. Leal
Keyword(s):  
Oviposition Behavior ◽  
Odorant Receptors ◽  
Direct Link ◽  
Mosquito Oviposition

scholarly journals A Highly Sensitive and Selective Colorimetric Hg2+ Ion Probe Using Gold Nanoparticles Functionalized with Polyethyleneimine

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Kyung Min Kim ◽  
Yun-Sik Nam ◽  
Yeonhee Lee ◽  
Kang-Bong Lee
Keyword(s):  
Gold Nanoparticles ◽  
Secondary Ion Mass Spectrometry ◽  
Color Change ◽  
Colorimetric Assay ◽  
Tap Water ◽  
Interparticle Distance ◽  
Pond Water ◽  
Assay Method ◽  
Tuna Fish ◽  
Highly Sensitive

A highly sensitive and selective colorimetric assay for the detection of Hg2+ ions was developed using gold nanoparticles (AuNPs) conjugated with polyethyleneimine (PEI). The Hg2+ ion coordinates with PEI, decreasing the interparticle distance and inducing aggregation. Time-of-flight secondary ion mass spectrometry showed that the Hg2+ ion was bound to the nitrogen atoms of the PEI in a bidentate manner (N–Hg2+–N), which resulted in a significant color change from light red to violet due to aggregation. Using this PEI-AuNP probe, determination of Hg2+ ion can be achieved by the naked eye and spectrophotometric methods. Pronounced color change of the PEI-AuNPs in the presence of Hg2+ was optimized at pH 7.0, 50°C, and 300 mM·NaCl concentration. The absorption intensity ratio (A700/A514) was correlated with the Hg2+ concentration in the linear range of 0.003–5.0 μM. The limits of detection were measured to be 1.72, 1.80, 2.00, and 1.95 nM for tap water, pond water, tuna fish, and bovine serum, respectively. Owing to its facile and sensitive nature, this assay method for Hg2+ ions can be applied to the analysis of water and biological samples.

Singly laid mole salamander (Ambystoma talpoideum) eggs resist mortality from water mold infection

Behaviour ◽  
2014 ◽  
Vol 151 (1) ◽  
pp. 125-136
Author(s):  
Dean A. Croshaw
Keyword(s):  
Population Biology ◽  
Oviposition Behavior ◽  
Positive Association ◽  
Egg Laying ◽  
Physical Contact ◽  
Embryo Viability ◽  
Egg Survival ◽  
Significant Positive Association ◽  
Water Mold ◽  
Mole Salamander

Parasites and pathogens are noteworthy forces in evolutionary and population biology. Water molds are known to infect and kill amphibian eggs, and masses placed in clusters sometimes suffer greater losses. Thus, selection may favor single oviposition behavior in which females scatter individual eggs to avoid contact with dead eggs, thereby lowering the chances of hyphal spread. I tested the hypothesis that eggs in physical contact with dead eggs are more susceptible to death via pathogen infection using a singly laying urodele, the mole salamander, whose congeners mostly lay eggs in masses. Focal eggs were placed in replicated containers with variable egg contact (physically touching or separated) by treatment eggs that varied in status (dead or alive). The effect of egg arrangement was significant, with focal eggs surviving better to hatching when not contacting treatment eggs. Although treatment egg status (dead vs. alive) was not influential on its own, the interaction between egg contact and status was an important determinant of focal egg survival. Only when eggs were physically touching was it important whether they were dead or alive. Moreover, when eggs were touching there was a significant positive association between focal egg survival and the number of surviving treatment eggs. Water mold infected most dead eggs in all treatment groups. This study shows that mole salamander eggs are more likely to die when touching other eggs that have perished, most likely because of a greater chance of water mold infection. Such mortality may have contributed to diversification of egg-laying behavior in amphibians and shows a potentially compounding fitness cost of diminished fertilization success and embryo viability.

scholarly journals Early introduction of water and complementary feeding and nutritional status of children in northern Senegal

2007 ◽  
Vol 10 (11) ◽  
pp. 1299-1304 ◽  
Author(s):  
Neil Gupta ◽  
Mario Gehri ◽  
Nicolas Stettler
Keyword(s):  
Nutritional Status ◽  
Tap Water ◽  
Large Family ◽  
Pond Water ◽  
World Health ◽  
Reverse Causality ◽  
Cross Sectional ◽  
Early Introduction ◽  
Increased Risk ◽  
Nutritional Status Of Children

AbstractObjectiveMalnutrition is responsible globally for 60% of deaths among children under 5 years and is often attributed to suboptimal feeding practices. In response, the World Health Organization recommends exclusive breast-feeding for the first 6 months of life. The objective of this study was to determine if an association exists between the early introduction of water and complementary foods (CFs) and the nutritional status of children in northern Senegal.Design/Setting/SubjectsA cross-sectional study of 374 children in the Podor Health District between the ages of 6 and 23 months was conducted. Knowledge and behaviours of mothers regarding introduction of water and CFs were assessed via individual interviews.ResultsWater was introduced to about 85% of the children in the first 3 months of life and 62% were fed CFs before 6 months. Overall, 16% had clinically significant wasting (weight-for-length Z-score (WHZ) less than − 2) and 20% had stunting (height-for-age Z-score (HAZ) less than − 2). There was no significant association between wasting or stunting and introduction of water before 3 months (WHZ: odds ratio = 0.99, 95% confidence interval 0.46–2.14, P = 0.97; HAZ: 0.68, 0.34–1.36, P = 0.3) or introduction of CFs before 6 months (WHZ: 0.81, 0.46–1.42, P = 0.5; HAZ: 0.79, 0.46–1.35, P = 0.4). A significant association was found between wasting and male sex, age, living in Guede community, drinking river/pond water and large family size, while stunting was associated with age and drinking tap water.ConclusionThe results of the present study suggest that early introduction of water and CFs is frequent and is not associated with increased risk for malnutrition among children from this region of northern Senegal, but the possibility of reverse causality cannot be excluded.

Sign in / Sign up

Export Citation Format

Share Document