The present research aimed at evaluating the influence of the water quality in the life cycle and attraction of Aedes aegypti (L.) females to oviposit using different sources of water (raw sewage, effluent of UASB reactor, effluent of polishing lagoon, effluent of anaerobic filter, rain water and de-chlorinated water). The immature development time and survivorship were evaluated on a daily basis in two distinct feeding systems (with and without food). The quality of the water was shown to affect the egg and larval stages, but not the pupal or the adult. In the absence of food, no development was observed in rain water and de-chlorinated water. Immature development was faster in water sources from raw sewage, although with the lowest survivorship (37.3%). Free-choice tests indicated that females preferred to lay most of their eggs on water collected from the effluent of a UASB reactor, achieving the highest oviposition activity index (OAI) of 0.57. In non-choice tests, females laid larger batches of eggs in water collected from anaerobic filters (204.8 eggs), with the lowest number of eggs being laid on de-chlorinated water (37.3 eggs). It can be concluded that A. aegypti does not demonstrate any particular preference to lay eggs on clean water. This has serious implications for developing strategies to manage populations of this important vector in urban areas as it was shown to lay eggs and successfully develop on several different sources of water.

A presente pesquisa teve por objetivo avaliar a influência da densidade larval sobre o ciclo de vida, tamanho e fecundidade de Aedes aegypti (L.). Os bioensaios foram conduzidos a 26 ± 2ºC e 12h de luz. Foram utilizadas cinco densidades larvais (200, 500, 750, 1000 e 1250 larvas/l) e dois sistemas de alimentação (um com alimentação fixa de 100 mg de ração e outro com quantidade de alimento proporcional ao número de larvas/bandeja). Avaliou-se diariamente, o tempo de desenvolvimento e sobrevivência de ovo e larva, a razão sexual, a longevidade, a fecundidade e o tamanho dos adultos. O ciclo de vida de A. aegypti foi significativamente afetado pela densidade quando ofertados 100 mg de ração por bandeja. O período de desenvolvimento larval aumentou de 8,3 para 37,9 dias, a fecundidade diminuiu de 105,7 para 41,8 ovos/fêmea assim como o comprimento alar de 4,6 mm para 3,6 mm, quando comparadas às densidades de 200 para 1250 larvas/l, respectivamente. Não foram detectadas diferenças significativas dessas variáveis quando foram ofertados 1,9 mg de ração por larva, exceto para o tamanho dos adultos. Fêmeas criadas a 1250 larvas/l foram maiores, com comprimento alar médio de 5,2 mm.

We focused on the evaluation of the influence that the larval density have on the life cycle, size and fecundity of Aedes aegypti (L.). The bioassays were conducted at 26 ± 2ºC and at 12h light. Five larval densities (200, 500, 750, 1000 and 1250 larvae/l) and two feeding systems (one with a fixed amount of 100 mg of food, and other with an amount of food proportional to the number of larvae/tray) were tested. Egg and larval development time and survivorship, sex ratio, longevity, fecundity and the size of adults were evaluated on a daily basis. The life cycle of A. aegypti was significantly affected by the density when offered 100 mg of food per tray. The period of larval development increased from 8.3 to 37.9 days whereas female fecundity and wing length decreased from 105.7 to 41.8 eggs/female and from 4.6 mm to 3.6 mm, respectively, by changing from a density of 200 to 1250 larvae/l. Significant differences of these variables were not detected when offering 1.9 mg of food per larvae, except for the size of the adults. Females emerged from rearing densities of 1250 larvae/l grew larger, with an average wing length of 5.2 mm.

O trabalho teve por objetivo avaliar o efeito da qualidade da água no desenvolvimento de Aedes aegypti (Linnaeus, 1762). O ciclo de vida desse vetor foi estudado em águas de esgoto bruto, efluente de reator UASB, efluente de lagoa de polimento, efluente de filtro anaeróbio, água de chuva e água desclorada. Diariamente avaliaram-se o período de desenvolvimento e as viabilidades de ovo, larva, pupa, longevidade e a fecundidade dos adultos. A duração do período larval variou de 5,6 a 9,1 dias, sendo a sobrevivência baixa em águas de esgoto bruto, efluente de reator UASB, efluente de lagoa de polimento e efluente de filtro anaeróbio. Não foram observadas diferenças nas durações e viabilidades das fases de ovo e pupa, longevidade e fecundidade dos adultos. Constatou-se que, apesar da baixa viabilidade larval, é possível o desenvolvimento do A. aegypti em águas com elevados graus de poluição e que todos os tratamentos permitiram o desenvolvimento desse vetor.

The present work aimed to estimate the effect of water quality in the development of Aedes aegypti (Linnaeus, 1762). The life cycle of this vector was studied in raw sewage water, effluent of UASB reactor, effluent of polishing lagoon, effluent of anaerobic filter, rainwater and de-chlorinated water. The development period, egg viability and larval and pupal survival were evaluated daily as well as the adult longevity and fecundity. The duration of larval period showed a variation of 5.6 to 9.1 days. Survival was considered low in raw sewage water, effluent of UASB reactor, effluent of polishing lagoon and effluent of anaerobic filter. No difference in terms of the duration and egg and pupal viability nor in the adult longevity and fecundity was detected. It was verified that despite a reduction in larval viability, A. aegypti could accomplish total development in waters with high pollution degree and that all the treatments were suitable to the development of this vector.

O trabalho teve por objetivo avaliar o efeito da temperatura sobre o ciclo de vida de Aedes aegypti (Linnaeus, 1762), determinar as exigências térmicas para o desenvolvimento e estimar o número de gerações anuais do inseto em campo. O ciclo de vida das populações de A. aegypti foi estudado nas temperaturas de 18, 22, 26, 28, 32 e 34 ± 2ºC e fotofase de 12 horas, determinando-se ainda os limites térmicos inferiores de desenvolvimento (Tb) e as constantes térmicas (K) e estimado o número de gerações anuais do inseto em laboratório e em campo. A temperatura favorável ao desenvolvimento de A. aegypti encontra-se entre 22ºC e 32ºC, e para a longevidade e fecundidade dos adultos entre 22ºC e 28ºC. As Tb, K de ovo a adulto, e o número de gerações anuais em campo foram de 11,33; 8,99 e 13,61ºC, 192,3; 213,2 e 116,5 graus-dias, e 23; 24,6 e 30,3 gerações para as populações de A. aegypti de Boqueirão (07º29'27''S, 36º08'09''W), Campina Grande (07º13'32''S, 35º54'15''W) e Remígio (06º58'1''S, 35º47'29''W), respectivamente.

The present work aims at estimating, based on a biological study, the thermal exigencies to the development and the number of generations per year of Aedes aegypti (Linnaeus, 1762) (Diptera, Culicidae) in field. The life cycle of the A. aegypti populations has been studied at constant temperatures of 18, 22, 26, 28, 32 and 34 ± 2ºC, and 12 hours photophase. The low threshold temperature of development (Tb) and the thermal constant (K) have been determined. The number of generations per year in laboratory and field has also been estimated. The favourable temperature to the A. aegypti development its between 22ºC and 32ºC, and to the longevity and fecundity A. aegypti adult its between 22ºC and 28ºC. The egg to adult basal temperature, thermal constant and the number of generations in field were, in order, 11.33; 8.99 and 13.61 ºC, 192.3; 213.2 and 116.5 graus-days, and 23; 24.6 and 30.3 generations to A. aegypti populations from Boqueirão (07º29'27''S, 36º08'09''W), Campina Grande (07º13'32''S, 35º54'15''W) and Remígio (06º58'1''S, 35º47'29''W).