Eclosion rate, development and survivorship of Aedes albopictus (Skuse)(Diptera: Culicidae) under different water temperatures

Abstract

Neotropical Entomology 36 (6):966-971 (2007) Eclosão, Desenvolvimento e Sobrevivência de Aedes albopictus (Skuse) (Diptera: Culicidae) sob Diferentes Condições de Temperatura da Água RESUMO -Em áreas tropicais, onde as populações de insetos vetores são particularmente abundantes, as temperatura usualmente variam entre 25°C e 35°C. Considerando a importância dessa variação na determinação da dinâmica populacional de mosquitos, neste trabalho, desenvolvimento e as taxas de eclosão e sobrevivência dos estágios imaturos de Aedes albopictus (Skuse) foram comparados sob temperaturas constantes de 25, 30 e 35°C (em câmaras climatizadas) e ambientes (25°C a 29°C). A taxa de eclosão foi considerada como o total de larvas obtidas após 24h. O período de desenvolvimento, assim como a taxa de sobrevivência larval e pupal foram avaliados diariamente. A taxa de eclosão foi signifi cativamente mais elevada sob temperatura ambiente comparada às constantes, sugerindo que a variação da temperatura pode ser um fator estimulante da eclosão. O tempo médio de eclosão aumentou com a temperatura, variando de 2,8h (25ºC) a 5,2h (35ºC). A duração do período larval apresentou grande variabilidade dentro de cada grupo, embora não tenha diferido signifi cativamente entre os mesmos (11,0 ± 4,19 dias), tendo sido mais longo para indivíduos mantidos na água a 35°C (12,0 ± 4,95 dias) e temperatura ambiente (13,6 ± 5,98 dias). Ao contrário, a sobrevivência das larvas foi fortemente afetada na temperatura mais elevada, onde apenas um indivíduo alcançou o estágio adulto. Esses resultados sugerem que a população de Ae. albopictus de Recife pode estar em processo de adaptação ao aumento de temperatura e que o limite para o desenvolvimento de estágios larvais se encontra próximo a 35°C. PALAVRAS-CHAVE: Biologia, vetor, ciclo de vida, limite térmicoABSTRACT -In tropical areas, where vector insects populations are particularly numerous, temperature usually range between 25°C and 35°C. Considering the importance of such temperature variation in determining mosquitoes population dynamics, in this work the developmental, eclosion and survival rates of the immature stages of Aedes albopictus (Skuse) were compared under constant 25, 30 and 35°C (using acclimatized chambers) and environmental (25°C to 29°C) temperatures. The hatching rate was considered as total number of larvae recovered after 24h. The development period as well as larval and pupal survival rate were evaluated daily. Eclosion rate was signifi cantly higher under environmental temperature than under the studied constant temperatures, suggesting that temperature variation may be an eclosion-stimulating factor. The mean eclosion time increased with the temperature, ranging from 2.8h (25°C) to 5.2h (35°C). The larval period was greatly variable inside each group, although it did not differ signifi cantly amongst groups (11.0 ± 4.19 days), with individuals showing longer larval stages in water at 35°C (12.0 ± 4.95 days) and environmental temperature (13.6 ± 5.98 days). Oppositely, survival was...

Temperature Effects on the Immature Development Time of Culex eduardoi Casal & García (Diptera: Culicidae)

“…As expected, the total development time (from irst instar larva to adult emergence) was inversely related to the rearing temperature in the range of 7 o C to 25 o C, as observed for several mosquito species (e.g., Rueda et al 1990, Mahamood & Crans 1998, Ribeiro et al 2004, Monteiro et al 2007. The time required by the immatures maintained at the lowest temperatures to reach adulthood was extended between six to eight orders of magnitude as compared for those maintained at 25°C.…”

“…Pupal survivorship ranged from 5% (5/92) at 7°C up to 13% (12/92) at 15°C, and no larvae completed their development in temperatures > 30 o C (Table 1). Nevertheless, other culicids common to the south of Brazil and Argentina are able to complete their development in temperatures between 30 o C and 35ºC (Calado & Navarro-Silva 2002, Ribeiro et al 2004, Monteiro et al 2007. However, none of them have been detected on latitudes higher than 40ºS.…”

“…The proportion of time spent in each stage varied between 7 o C and 25°C with respect to the total development time. However, like in Aedes albopictus (Skuse) (Calado & Navarro-Silva 2002, Monteiro et al 2007, the fourth instar was the longest stage, accounting for 25-36% of the total development time, what is probably related with the nature of the larval growth process, since most of the growth occurs during the last instar (Clements 1992).…”

The biology and demographic parameters of Aedes albopictus in northern peninsular Malaysia

“…In our experiment food was supplied in optimum amounts, and evidence exists that under such nutritional conditions, larval developmental period vary from 5 to 10 days [36] . Monteiro et al [37] recorded no adult emergence when immature stages of A. albopictus were maintained at 35 曟 and concluded that the limit temperature for the development of its larval stages is close to 35 曟 . Our result is consistent with a similar previous study in Penang [17] in indicating a short larval period of A. albopictus, although the environmental conditions are not identical.…”

Evaluation of Toxicity of Phenolic Compounds Using <i>Aedes aegypti</i> (Diptera: Culicidae) and <i>Artemia salina</i>

“…Two hundred Ae. aegypti eggs approximately 15 days old were used to avoid lowering the hatching rate [16] [17]. To check the incubation period and viability, the eggs were divided into five batches of 20 eggs each, which were kept in 20 mL test tubes, with 10 mL of water and fish food added to each tube.…”