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1.
Rev Soc Bras Med Trop ; 57: e007152024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39699543

RESUMO

BACKGROUND: Vector distribution influences arbovirus persistence. This study examined the diversity of mosquito breeding sites in an Atlantic Forest fragment in Rio de Janeiro, Brazil. METHODS: Mosquito specimens were collected at Fazenda dos Cordeiros, Silva Jardim, Brazil. Tire, plastic, bamboo, and sapucaia traps were evaluated for oviposition preferences using ecological indices. RESULTS: Tire traps had the highest density. Bamboo traps showed the highest diversity. Plastic container was the most divergent site. The key recorded vector species included Aedes albopictus and Haemagogus leucocelaenus. CONCLUSIONS: Identifying the breeding sites that contribute the most to mosquito density is essential for optimizing control strategies.


Assuntos
Culicidae , Florestas , Mosquitos Vetores , Densidade Demográfica , Animais , Brasil , Mosquitos Vetores/classificação , Mosquitos Vetores/fisiologia , Culicidae/classificação , Culicidae/fisiologia , Biodiversidade , Feminino , Aedes/fisiologia , Aedes/classificação , Oviposição/fisiologia
2.
Neotrop Entomol ; 54(1): 9, 2024 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-39668273

RESUMO

Seed beetles spend most of their lives within the seeds of host plants belonging to the Fabaceae family. Evidence suggests the cues that mediate pre-oviposition behaviour in Zabrotes subfasciatus (Boheman) are volatile organic compounds (VOCs) emitted by the seeds and suggests differential abilities in environment sensing between sexes. Here, we tested whether VOCs from different legume species trigger different levels of attraction, whether females and males differ in their ability to respond to VOCs, and whether the seeds promoting different behaviours feature singular VOCs. Finally, we tested females' response to selected VOCs from legume seeds with different levels of attraction. Behavioural assays testing the beetles' response to four Fabaceae species allowing varied levels of fitness (Phaseolus vulgaris, Glycine max, Lens culinaris, and Cicer arietinum) and antenna removal assays confirmed volatiles emitted by the seeds act as chemical cues for females and showed the seeds of the tested legume species trigger different levels of attraction. GC-MS analysis revealed the seeds of two of the species at the extreme of the preference hierarchy feature singular VOCs profiles and abundance. One of the differentially expressed VOCs found in higher quantities in P. vulgaris (ethenylbenzene = styrene) and one in C. arietinum (2-ethyl-1-hexanol) mediate opposing behaviours in Z. subfasciatus females. These results suggest host choice in Z. subfasciatus relies upon at least a two-component kairomone-based system: styrene attracts females to P. vulgaris seeds and 2-ethyl-1-hexanol keeps them from choosing C. arietinum as a substrate for oviposition. The system has evolutionary and agricultural relevance because it may allow for "niche" specialisation in seed stores and natural environments and may help develop pest management strategies.


Assuntos
Besouros , Fabaceae , Hexanóis , Sementes , Compostos Orgânicos Voláteis , Animais , Besouros/fisiologia , Feminino , Masculino , Sinais (Psicologia) , Oviposição/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas
3.
J Insect Sci ; 24(5)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39364798

RESUMO

Heilipus lauri is a specialist avocado seed feeding weevil native to parts of México and is an invasive pest in Colombia. This weevil is considered an incursion risk because possible unintended introductions into areas outside of its native range can result in establishment, which threatens avocado production in invaded regions. Despite being a well-recognized pest of avocados, relatively little is known about oviposition biology, behavior, and cultivar preferences of this weevil. Field studies in commercial Hass avocado orchards in México and laboratory studies in a quarantine facility in California (USA) indicated that H. lauri prefers to oviposit into middle and bottom thirds of fruit. In the laboratory, an average of 1.7 eggs (range 1-6 eggs) are laid over a 24-h period in oviposition chambers by individual females. Conspecifics add eggs to these clutches, with up to 17 eggs being recorded in 1 oviposition chamber. This finding suggests that H. lauri does not use an oviposition deterring pheromone. Female weevils readily oviposit in artificial holes representing mechanical wounds on fruit. In comparison to the commercially dominant Hass variety, fruit from Lamb Hass and G22, a native Guatemalan variety, and to a lesser extent Gem, may be less preferred for oviposition when females have a choice of fruit in which to oviposit. Videography studies indicated that H. lauri exhibits predominantly diurnal activity with respect to oviposition behaviors, feeding, and walking.


Assuntos
Oviposição , Persea , Gorgulhos , Animais , Feminino , Gorgulhos/fisiologia , Frutas , México , California
4.
An Acad Bras Cienc ; 96(4): e20240632, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39383354

RESUMO

Telenomus remus (Hymenoptera: Scelionidae) is an efficient parasitoid of Spodoptera eggs. However, biological control programs require taxonomic, bioecological and behavioral studies of biological agents. Although the performance of T. remus in pest control has been evaluated, little is known about its behavioral aspects that can influence IPM tactics. The aim of this study was therefore to study the parameters related to the oviposition behavior of T. remus on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs. The experiment was conducted in the laboratory, where 17 females were transferred individually to arenas containing a mass of S. frugiperda eggs. Oviposition behavior was recorded for 30 minutes. The average walking speed of the females was 0.116 mm.s-1 and the total distance covered was 203.3 mm. The females remained on the egg masses for an average of 16.7 min, which corresponds to more than half of the total time. The average number of parasitized eggs was 15.1 per female in 30 minutes. Females with larger antennae had lower values for average speed and total distance covered. The results of the parameters evaluated show the standard oviposition behavior of T. remus females on S. frugiperda eggs and help us to better understand the species.


Assuntos
Oviposição , Spodoptera , Animais , Oviposição/fisiologia , Feminino , Spodoptera/parasitologia , Spodoptera/fisiologia , Controle Biológico de Vetores , Óvulo/fisiologia , Óvulo/parasitologia , Himenópteros/fisiologia , Vespas/fisiologia , Interações Hospedeiro-Parasita
5.
Braz J Biol ; 84: e285828, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39383415

RESUMO

Calcium (Ca) is an essential mineral for eggshell formation and muscle contraction, and a lack of it can result in poor egg quality and decreased egg output in laying ducks. This study aims to see how feeding the mineral Ca in a ration containing Shrimp head meal and Bilis fish head affects the laying performance and quality of hatching eggs in Mojosari ducks. A total of 105 female and 15 male Mojosari ducks, aged 78 weeks, were raised for three months and randomly divided into 15 flocks (each flock containing seven females and one male duck). There were three kinds of treatment, namely P0 (control, without mineral), P1 (ratio of Shrimp head meal and Bilis fish head 2:1 + 1% mineral), and P2 ((ratio of Shrimp head meal and Bilis fish head 1:2 + 1% mineral). The findings revealed that adding mineral Ca to feed, including Shrimp head meal and Bilis fish head, had no significant influence (P>0.05) on laying Mojosari duck performance in terms of feed intake, egg production, egg weight, egg quality, ducklings produced, and income over feed cost (IOFC). Furthermore, Ca addition in the ration did not result in substantial increases (P>0.05) in fertility, hatchability, or egg size characteristics. Based on the findings of this study, feeding ducks with shrimp head meal and Bilis fish head can be used as an alternate calcium-free feed formulation.


Assuntos
Ração Animal , Cálcio , Patos , Animais , Patos/fisiologia , Feminino , Ração Animal/análise , Masculino , Cálcio/análise , Oviposição/efeitos dos fármacos , Oviposição/fisiologia , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Distribuição Aleatória
6.
Sci Rep ; 14(1): 24803, 2024 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-39438582

RESUMO

This study was conducted with the objective of evaluating the impact of replacing inorganic mineral sources (IM) with amino acid complexed minerals (AACM) in laying hens' diets on performance, egg quality, bone, and intestinal health. The effects of 4 different diets with varying levels of AACM substitution were evaluated on 400 Lohmann White hens aged 78-98 weeks. The control diet contained only IM sources at levels of 60, 60, 7, 40, 0.2, and 2 mg/kg of Zn, Mn, Cu, Fe, Se, and I, respectively. The other treatments were made by a total substitution of IM with AACM, as follows: AACM70-70% of IM levels; AACM50-50% of IM levels; and AACM40-40% of IM levels. Orthogonal polynomial contrasts and Dunnett's test were used to determine their impact (P < 0.05). The treatment AACM40 improved egg production, egg weight, egg mass, and feed conversion ratio (P < 0.05). Hens that received AACM40 also produced the thickest eggshells and better tibial bone density (P < 0.01). Histomorphometry analyses demonstrated significant effects of AACM treatments. The optimal supplementation levels of 24, 24, 2.8, 16, 0.08, and 0.8 mg/kg of Zn, Mn, Cu, Fe, Se, and I, respectively.


Assuntos
Aminoácidos , Ração Animal , Galinhas , Minerais , Animais , Aminoácidos/metabolismo , Minerais/metabolismo , Feminino , Ração Animal/análise , Ovos/análise , Suplementos Nutricionais , Dieta/veterinária , Densidade Óssea/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal , Oviposição/efeitos dos fármacos
7.
Braz J Biol ; 84: e283850, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39476008

RESUMO

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), an invasive and polyphagous pest affecting various vital crops globally, was studied to assess how different maize hybrids impact its biological parameters under controlled laboratory conditions. Maize, a crucial crop for food security in Egypt, requires effective Integrated Pest Management (IPM) strategies to manage pests like S. frugiperda. This article explores how S. frugiperda performs on five maize hybrids-Hi-Tech 2031, Wataniya 6, Giza 10, Giza 128, and Giza 168. Significant differences were observed in larval duration across the hybrids, with the shortest duration (14.08 days) on Hi-Tech 2031. Giza 128 resulted in the longest pupal period (9.39 days), and adult lifespans varied between 8.91 and 9.61 days. Reproductive parameters also diverse, with pre-oviposition periods ranging from 4.64 to 4.90 days and oviposition periods from 3 to 4.14 days. The highest average egg count (1352.19 eggs) was recorded with Giza 10. Hybrids Hi-Tech 2031 and Giza 128 had a lower male proportion (44.81% and 43.45%, respectively). Giza 10 also yielded the highest pupation rate (93.33%), while Hi-Tech 2031 showed the highest emergence rate (96.33%).


Assuntos
Larva , Spodoptera , Zea mays , Animais , Zea mays/parasitologia , Spodoptera/fisiologia , Feminino , Masculino , Oviposição/fisiologia , Fatores de Tempo , Hibridização Genética , Reprodução/fisiologia
8.
Bull Entomol Res ; 114(5): 691-698, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39421890

RESUMO

Global warming has driven changes in the biology and fitness of organisms that need to adapt to temperatures outside of their optimal range to survive. This study investigated aspects of reproduction and survival of the lady beetle Tenuisvalvae notata (Mulsant) (Coleoptera: Coccinellidae) subjected to temperatures that varied from its optimal (28°C) to a gradual decrease (12, 14, 16, and 18°C) and increase (32, 34, 35, and 36°C) over time at a rate of 1°C/day. Fertility, fecundity, oviposition period, and survival were determined. There was a significant reduction in fertility and fecundity at temperatures below 18°C and above 34°C, whereas survival was reduced only above 34°C. Additionally, we evaluated that fecundity was the lowest when females were kept at low temperature, and when males were kept under high temperature. Therefore, if the T. notata remained for a long period under exposure to temperatures outside the ideal range, then the species could present different reproductive responses for each sex to high and low temperatures. This factor must be considered when releasing natural enemies into an area to understand the effect of temperature on the decline of a local population a few generations after release.


Assuntos
Besouros , Fertilidade , Temperatura , Animais , Besouros/fisiologia , Feminino , Masculino , Reprodução , Oviposição , Longevidade
9.
Exp Appl Acarol ; 93(4): 831-845, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39320533

RESUMO

Raoiella indica Hirst has rapidly and widely spread throughout the New World since 2004, primarily infesting coconut palms and interacting with the predator Amblyseius largoensis (Muma). Although A. largoensis feeds on R. indica at all stages of development, it cannot naturally reduce its population to levels that do not impact the host plant. Raoiella indica possesses dorsal setae that secrete exudates during all post-embryonic developmental stages, and females have a behavior that deliberately deposits droplets on the freshly laid egg, possibly as a defense strategy against predation in vulnerable stages. In this context, we analyzed whether the presence or absence of droplets in R. indica eggs affects predation using A. largoensis as a biological model. Thus, we evaluated whether some biological and behavioral characteristics of A. largoensis could be affected by the consumption of R. indica egg masses washed or unwashed with water. Also, we performed a chemical analysis of the droplets exuded by R. indica and provided a description of the oviposition behavior of R. indica. The predator showed a higher consumption rate and preference for washed eggs. The results suggest that the exudate droplets have defensive functions, which are incorporated by the female onto the egg during oviposition and subsequently during a patrolling behavior, as they lose their effect after being washed with water. Although the droplets do not prevent the predator from feeding, they reduce the number of R. indica eggs consumed without affecting the growth of A. largoensis.


Assuntos
Oviposição , Óvulo , Comportamento Predatório , Animais , Feminino , Óvulo/fisiologia , Óvulo/crescimento & desenvolvimento , Ácaros/fisiologia , Ácaros/crescimento & desenvolvimento , Besouros/fisiologia , Exsudatos e Transudatos/química
10.
Neotrop Entomol ; 53(5): 1149-1157, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39141219

RESUMO

Coffee berry borer (CBB) Hypothenemus hampei is a major biotic threat to coffee production worldwide. Studies have reported negative effects on CBB by oil-based formulations of neem (Azadirachta indica), but little information is available for other neem-extract formulations. This study evaluated CBB preference and performance in arabica coffee fruits and artificial diet treated with a neem-extract formulation (Openeem Plus®) in the field and laboratory conditions. Field experiments were performed using CBB females artificially infested in cherry or green coffee fruits confined in voile-fabric cages tied to branches of neem-treated and control plants, recording the adult mortality and offspring production. Dual-choice and no-choice bioassays assessed CBB preference and development in fruits and artificial diet treated with the neem extract compared to controls in the laboratory, respectively. As main results obtained in the field and laboratory experiments, the neem extract significantly reduced CBB oviposition in both cherry and green fruits, as well as in artificial diet compared to controls. However, the botanical product did not affect CBB adult survival and preference in the laboratory bioassays. The neem extract is promising for use in pest management strategies in sustainable arabica coffee crops by reducing CBB oviposition and offspring. These effects can contribute to lowering the pest population buildup along the crop cycle and damage potential to coffee production.


Assuntos
Azadirachta , Coffea , Frutas , Oviposição , Gorgulhos , Animais , Feminino , Oviposição/efeitos dos fármacos , Dieta , Controle de Insetos/métodos
11.
PeerJ ; 12: e17929, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39184387

RESUMO

Background: Gonipterus platensis Marelli, 1926 (Coleoptera: Curculionidae) is one of the main defoliating beetles in Eucalyptus plantations. Biological control with egg parasitoids is one of the main control strategies for this pest and a constant supply of fresh host eggs is required to rear the parasitoids. Polyandry can influence Gonipterus oviposition by increasing female fecundity and fertility; however, the high density of individuals in laboratory colonies can lead to male harassment, resulting in lower reproduction rate. The aim of this study was to measure the effects of monoandry and polyandry on the reproduction of G. platensis and the effects of male harassment on laboratory rearing conditions. Methods: Reproductive parameters were compared between three treatments: monoandry, where the female was allowed to mate daily with the same male; no choice polyandry, where the female was allowed to mate daily with a different male; and polyandry with choice, where the female was allowed to mate daily, but with a choice between five different males. Another experiment varying the density of males was conducted to evaluate the effect of male harassment. Results: Polyandry with choice resulted in the longest period of oviposition, highest fecundity and highest number of eggs per egg capsules when compared to monoandrous females. No negative effect related to male harassment in the laboratory, such as decreased fertility, fecundity, or number of eggs per egg capsule, was detected. Conclusion: Polyandry contributes to mass rearing as it increases fecundity and oviposition period on females and there is no evidence of male harassment on G. platensis.


Assuntos
Fertilidade , Oviposição , Comportamento Sexual Animal , Animais , Feminino , Masculino , Oviposição/fisiologia , Comportamento Sexual Animal/fisiologia , Fertilidade/fisiologia , Gorgulhos/fisiologia , Controle Biológico de Vetores/métodos , Reprodução/fisiologia
12.
J Am Mosq Control Assoc ; 40(3): 145-148, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39089686

RESUMO

It is estimated that there are over 500 species of arboviruses worldwide, with more than 150 of them directly associated with human diseases, the majority of which are zoonotic. Among the main arboviruses circulating in Brazil, dengue, Zika, and chikungunya stand out, all transmitted through a common vector, Aedes aegypti. Given this scenario, the development and implementation of more efficient surveillance strategies become urgent. This study aims to compare and evaluate the efficiency of beetroot peel, Beta vulgaris, as an attractant for Ae. aegypti oviposition under field conditions in the municipality of Agrestina, State of Pernambuco, Brazil. Beetroot peel extract is a cheap and accessible source of geosmin, which holds significant potential as an attractant for mosquitoes due to its resemblance to microbial volatiles found in water bodies rich in organic material. During the study period (November 2023 to April 2024), 40 traps were set in each neighborhood, with 20 of each attractant. Two traps were used per property, one following the traditionally used model (beer yeast infusion) and another containing beetroot peel. Overall, in both analyzed neighborhoods (Campo Novo and Cohab), beetroot peel appeared to be a more efficient attractant for the oviposition of culicids. Beetroot peel showed the highest values in egg abundance and in the analyzed indices.


Assuntos
Aedes , Beta vulgaris , Controle de Mosquitos , Mosquitos Vetores , Oviposição , Animais , Brasil , Beta vulgaris/química , Feminino , Arbovírus
13.
J Insect Physiol ; 158: 104699, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-39197709

RESUMO

Mating and the transfer of seminal fluid components including male accessory glands (MAGs) proteins can affect oviposition behavior in insects. After oviposition, some species of fruit flies deposit a host-marking pheromone (HMP) on the fruit that discourages oviposition by other females of the same or different species or genus and reduces competition between larvae. However, we know very little about how mating, receiving seminal fluid, or male condition can affect female host marking behavior. Here, we tested how the physiological state of females (mated or unmated), the receipt of seminal fluid, and the condition of the male (wild or sterile) affect oviposition and host-marking behavior (HMB) in Anastrepha ludens (Diptera: Tephritidae). We also determined the efficiency of the host-marking pheromone from mated or unmated females in deterring oviposition. In a further examination of how seminal fluid may be affecting HMB we assessed if there were differences in the size of wild or sterile MAGs and the protein quantity transferred during mating. Our results indicate that receiving seminal fluid increased egg laying and increased time invested in host-marking (HM). Unmated females laid fewer eggs than mated females but invested the same amount of time in depositing host-marking pheromone, which had similar effectiveness in deterring oviposition as that of mated females. Females that mated with sterile males laid the same number of eggs as females that mated with wild males but spent less time depositing host-marking pheromone, which suggests that females detect the condition of the male and invest less in marking hosts. Finally, sterile males had larger accessory glands and transferred more MAGs proteins during mating compared to wild males. Seminal proteins could be manipulating HM behavior and female investment into their current reproductive effort. We are only beginning to understand how male condition and seminal fluid can affect female physiology and maternal investment in HMP.


Assuntos
Oviposição , Sêmen , Comportamento Sexual Animal , Tephritidae , Animais , Masculino , Feminino , Tephritidae/fisiologia , Comportamento Sexual Animal/fisiologia , Sêmen/fisiologia , Feromônios
14.
Acta Trop ; 258: 107325, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39032848

RESUMO

Proposing substitutes for Pyriproxyfen (PPF) in the auto-dissemination strategy is essential to ensure the continuity of the strategy in the field, especially in the case of the emergence of populations resistant to this larvicide. One possible substitute among the compounds already in use in Brazil is the larvicide Diflubenzuron (DFB). The equation that defines the proportion of oviposition sites (habitats) contaminated by the auto-dissemination strategy was modified to account for the number of visits required to reach the necessary concentration of DFB for contamination, considering scenarios with varying numbers of oviposition sites and mosquito densities. The dissemination was evaluated in oviposition sites of 2 L, 1.5 L, 1 L, 0.5 L, 0.2 L, and 0.1 L. The minimum concentration of active ingredient (a.i) of DFB required for a commercial product to contaminate at least 50% of oviposition sites was also investigated, along with the impact of other vector control methods, such as the removal/destruction of oviposition sites and the use of insecticides to kill adult 'females, on the auto-dissemination approach. The use of pure DFB compounds enabled contamination efficiency of more than 50% in oviposition sites with a volume of less than 2 L in scenarios with fewer oviposition sites. On the other hand, with the use of the commonly used concentration of the product, similar efficacy was only achieved in oviposition sites of 0.1 L and 0.2 L in medium and high infestation scenarios. Strategies that reduce the number of available oviposition sites work synergistically with the auto-dissemination strategy, making it possible to use less concentrated products and contaminated sites of larger volume. The strategy proved to be resilient in situations of insecticide application according to the concentration of DFB used, abundance of females, and low number of oviposition sites. Increasing the number of dissemination traps on the field also contributes to better results, especially for oviposition sites of 0.5 L and 1 L. The results of the model obtained under the stipulated conditions provide further support for the potential use of DFB as a substitute for PPF in the auto-dissemination strategy.


Assuntos
Diflubenzuron , Inseticidas , Larva , Controle de Mosquitos , Oviposição , Animais , Inseticidas/farmacologia , Diflubenzuron/farmacologia , Oviposição/efeitos dos fármacos , Controle de Mosquitos/métodos , Feminino , Brasil , Larva/efeitos dos fármacos , Culicidae/efeitos dos fármacos
15.
Neotrop Entomol ; 53(4): 738-745, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955945

RESUMO

Palpita forficifera Munroe, 1959 (Lepidoptera: Crambidae) is considered the main pest of the olive tree (Olea europaea L., Oleaceae) in Brazil and Uruguay. The aim of this work was to study the mating and oviposition behavior of P. forficifera in the field and laboratory. In the field, the sex emitting the mating pheromone was determined and in the laboratory, the rate of emergence of males and females; the age, time and duration of mating; number of copulations and oviposition time of P. forficifera were recorded. The field results showed that it was possible to capture up to five males per trap in just one night in traps with the presence of female P. forficifera. Copulation occurs between the seventh and twenty-third day of life and is most frequent during the third and sixth hours of scotophase. The average duration of the first copulation was 174 min, with 35% of couples recopulating, and there were cases of up to five copulations. Oviposition times were concentrated between 20:00 and 02:00. The results obtained provide insight into the reproductive behavior of P. forficifera and are useful for future studies aimed at identifying the sex pheromone to improve monitoring of the pest in olive orchards.


Assuntos
Oviposição , Comportamento Sexual Animal , Animais , Feminino , Masculino , Lepidópteros/fisiologia , Mariposas/fisiologia
16.
Braz J Biol ; 84: e283484, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985072

RESUMO

The date palm mite, Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae), is a serious pest of dates in the Middle East and North Africa, inflicting severe economic damage if not controlled early. As predaceous mites are known to be potential biocontrol agents against several pests, so predation capacity, life table, reproduction, and survival of Amblyseius swirskii Athias-Henriot and Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae), collected from date palm farms in Qassim Saudi Arabia, were studied under laboratory conditions (25 °C, 30 °C, 35 °C and 50 ± 5% RH) against all motile stages of O. afrasiaticus. For both predators, mean developmental time, oviposition period, and longevity were inversely related to temperature from 25 to 35 °C. Various parameters were studied for A. swirskii and N. cucumeris at 25 °C, 30 °C and 35 °C, i.e. the female developmental time, 9.37, 7.29, 5.56, and 10.67, 8.38, 6.45 d; oviposition period, 19.77, 16.18, 13.94 and 15.90, 13.84, 10.64 d; longevity, 29.39, 24.79, 20.64 and 25.42, 21.94, 17.39 d; fecundity, 31.91, 37.10, 42.16 and 21.75, 26.84, 30.56 eggs per female, respectively. The maximum daily predation rate for both the predators was recorded at 35 °C during the oviposition period. The total predation of A. swirskii and N. cucumeris female was 370.86, 387.54, 405.83, 232.14, 263.32, 248.85 preys at 25 °C, 30 °C and 35 °C respectively. The maximum reproduction rate of A. swirskii and N. cucumeris (3.02, 2.87 eggs/♀/day) was recorded at 35 °C while the minimum (2.00, 1.36 eggs/♀/day) was recorded at 25 °C. The life table parameters were estimated as net reproductive rate (Ro) 21.68, 25.94, 29.52 and 18.95, 20.25, 22.78; the mean generation time (T) 24.92, 21.82, 18.24 and 26.30, 23.60, 20.56 d; the intrinsic rate of increase (rm) 0.181, 0.232, 0.248 and 0.170, 0.185, 0.196; the finite rate of increase (λ) 1.365, 1.551, 1.706 and 1.126, 1.324, 1.428 for A. swirskii and N. cucumeris at 25 °C, 30 °C and 35 °C respectively. The results of this study suggested that the two phytoseiid species are promising biological control agents of O. afrasiaticus at a wide range of temperatures.


Assuntos
Ácaros , Controle Biológico de Vetores , Phoeniceae , Comportamento Predatório , Animais , Feminino , Comportamento Predatório/fisiologia , Masculino , Ácaros/fisiologia , Phoeniceae/parasitologia , Oviposição/fisiologia , Tetranychidae/fisiologia , Reprodução/fisiologia , Longevidade , Estágios do Ciclo de Vida/fisiologia , Características de História de Vida
17.
Pest Manag Sci ; 80(11): 5619-5629, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38940546

RESUMO

BACKGROUND: Transgenic Bt technology in soybean, with plants expressing Cry1Ac, has been adopted as an insect pest management tool. It was first adopted in large areas of South America and Asia in 2013. The risk of resistance in target pests to this technology demands insect resistance management (IRM) programs. In Brazil, a structured refuge (area of non-Bt soybean) planted adjacent to the Bt soybean crop has been an important IRM recommendation, particularly for the primary lepidopteran defoliators Anticarsia gemmatalis (Lepidoptera: Erebidae) and Chrysodeixis includens (Lepidoptera: Noctuidae). The overall goal of this study was to validate IRM recommendations to Bt soybean. The objectives were to document the impact of soybean phenology, cultivar choice and non-Bt soybean defoliation on moth oviposition. In addition, a mark-release-recapture study estimated the dispersal capacity of these species. Five field experiments per species were performed for 3 years. RESULTS: Our results revealed an increase in A. gemmatalis and C. includens oviposition, respectively, on Bt plants as a consequence of the difference in plant growth stage at the time of oviposition. Defoliation of non-Bt plants significantly increased the oviposition preference of both moth species for Bt plants. The mark-release-recapture experiment indicated an average dispersal distance of ~300 m from the release point for A. gemmatalis, with maximum recapture at 1000 m. CONCLUSION: Overall, our findings emphasize the importance of planting synchronization of Bt soybean and the structured refuge. In addition, when operational aspects in large soybean areas challenge this recommendation, the priority should be for planting the refuge area first. This approach will minimize the impact of selective oviposition of A. gemmatalis and C. includens. © 2024 Society of Chemical Industry.


Assuntos
Glycine max , Mariposas , Oviposição , Plantas Geneticamente Modificadas , Glycine max/crescimento & desenvolvimento , Animais , Mariposas/fisiologia , Mariposas/crescimento & desenvolvimento , Toxinas de Bacillus thuringiensis , Endotoxinas , Proteínas Hemolisinas , Feminino , Brasil , Proteínas de Bactérias/genética
18.
J Exp Biol ; 227(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38826150

RESUMO

Gravid female lizards often experience reduced thermal preferences and impaired locomotor performance. These changes have been attributed to the physical burden of the clutch, but some authors have suggested that they may be due to physiological adjustments. We compared the thermal biology and locomotor performance of the lizard Liolaemus wiegmannii 1 week before and 1 week after oviposition. We found that gravid females had a thermal preference 1°C lower than that of non-gravid females. This was accompanied by a change in the thermal dependence of maximum running speed. The thermal optimum for locomotor performance was 2.6°C lower before oviposition than after. At relatively low temperatures (22 and 26°C), running speeds of females before oviposition were up to 31% higher than for females after oviposition. However, at temperatures above 26°C, females achieved similar maximum running speeds (∼1.5 m s-1) regardless of reproductive stage. The magnitude of the changes in thermal parameters and locomotor performance of L. wiegmannii females was independent of relative clutch mass (clutches weighed up to 89% of post-oviposition body mass). This suggests that the changes are not simply due to the clutch mass, but are also due to physiological adjustments. Liolaemus wiegmannii females simultaneously adjusted their own physiology in a short period in order to improve locomotor performance and allocated energy for embryonic development during late gravid stage. Our findings have implications for understanding the mechanisms underlying life histories of lizards on the fast extreme of the slow-fast continuum, where physiological exhaustion could play an important role.


Assuntos
Lagartos , Oviposição , Reprodução , Animais , Lagartos/fisiologia , Feminino , Reprodução/fisiologia , Oviposição/fisiologia , Temperatura , Corrida/fisiologia , Locomoção/fisiologia
19.
Braz J Biol ; 84: e282231, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808790

RESUMO

The technique of terrestrial sampling of boll weevil (BW) populations is expensive and inefficient over large areas, but may be cheaper and more efficient without involving the manipulation of cotton squares. The aim of this study was to develop a technique to sampling cotton squares based on the observation of opened and/or yellowing bracts to determine the need and efficacy of chemical control of BW in cotton crops. The first experiment aimed to estimate the ratio between the number of cotton squares with opened and/or yellowed bracts and that of squares with BW oviposition punctures. The second experiment, aimed to determine the efficacy of chemical control for BW by sampling cotton squares with opened and/or yellowed bracts. The ratio between the number of opened and/or yellowed bracts and the number of cotton squares with oviposition punctures was 2:1. The level and efficiency of chemical control of BW, based on the percentage and sampling of cotton plants with opened and/or yellowed bracts, was 5% and did not differ from the one based on the observation of cotton plants with 10% cotton squares with oviposition punctures by BW females. The control level based on sampling cotton plants with open and/or yellowing bracts was 5%. The efficiency of chemical insecticides using this economic threshold against the BW did not differ from that based on sampling cotton plants with 10% of cotton squares with oviposition punctures by BW females. This indicates that the chemical control of cotton boll weevil can be carried out based on cotton squares with open and/or yellowed bracts.


Assuntos
Gossypium , Controle de Insetos , Oviposição , Gorgulhos , Gorgulhos/fisiologia , Gossypium/parasitologia , Animais , Oviposição/fisiologia , Feminino , Controle de Insetos/métodos , Inseticidas
20.
PLoS One ; 19(5): e0301816, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38743802

RESUMO

The yeast-encapsulated orange oil (YEOO) is a novel larvicide under development against vector mosquitoes. Despite its efficiency against Aedes aegypti (L.) in small scale experiments, its applicability in vector control can be influenced by other effects on mosquito behaviour or physiology. For this reason, the impact of YEOO particles in mosquito oviposition was evaluated in laboratory and semi-field conditions. Oviposition assays with one gravid Aedes aegypti female were carried under laboratory and semi-field conditions with natural light and temperature fluctuation. For all ovitraps, the number of eggs was manually counted in the wooden paddle and in the solution of each ovitrap. The proportion of eggs between substrates (wooden paddle and solution) varied between conditions, with females in laboratory presenting a lower preference to lay eggs in paddles when compared with studies in semi-field. This behaviour shifts in laboratory can create challenges to extrapolate results from laboratory to the field. Here, studies in both conditions indicate a similar impact of YEOO particles in Aedes aegypti oviposition. The potential treatment concentration of YEOO particles presents a strong repellent/deterrent effect (-0.559 > OAI > -0.760) within the initial 72h of application when compared with water, and weak repellent/deterrent signal (OAI = -0.220) when compared against inactivated yeast. Control ovitraps with water were more positive for egg presence than treated ovitraps, while ovitraps with YEOO particles and inactivated yeast present similar number of positive ovitraps. It is possible that the repellent/deterrent action is partially driven by the delivery system, since most times Citrus sinensis EO oviposition repellent/deterrent signal is weak, and it seem influenced by solvent/delivery used. However, it is unclear how the yeast wall that protect/surrounds the orange oil will negatively affect oviposition since live yeast are normally consider an attractant for mosquito oviposition.


Assuntos
Aedes , Controle de Mosquitos , Oviposição , Óleos de Plantas , Aedes/fisiologia , Aedes/efeitos dos fármacos , Animais , Oviposição/efeitos dos fármacos , Feminino , Óleos de Plantas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/fisiologia , Mosquitos Vetores/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia , Repelentes de Insetos/farmacologia
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