Potencial de alimentação de Chrysoperla externa (Hagen, 1861) (Neuroptera, Chrysopidae) em diferentes densidades de Uroleucon ambrosiae (Thomas, 1878) (Hemiptera, Aphididae)

Abstract

ABSTRACT. Feeding potential of Chrysoperla externa (Hagen) (Neuroptera, Chrysopidae) in different densities of Uroleucon ambrosiae (Thomas) (Hemiptera, Aphididae). The feeding potential of 2 nd and 3 rd instar larvae of Chrysoperla externa (Hagen, 1861) in relation to different densities of 30, 40 and 50 nymphs of Uroleucon ambrosiae (Thomas, 1878) at 3 rd and 4 th instars was evaluated. The treatments were individualized into 2.5 cm in diameter and 8.5 cm tall flat bottom glass vials and maintained in a controlled environmental chamber at 25±2 ºC temperature, 70±10% RH and 14 h photophase. A completely randomized experimental design with 10 replications was used. The consumption of the prey nymphs by the predator larvae was evaluated after 1, 2, 4, 8, 16 and 24 h from the beginning of the experiment and at every subsequent 24 h period until 2 nd instar larvae molted or 3 rd instar larvae pupated. Results have shown that for 2 nd instar larvae, during the 1 h to 24 h period, there was a decreasing prey consumption at the 30 and 40 prey densities. However an increase in the consumption at the 50 prey density was observed. After this period, C. externa larvae presented a progressive increase on nymphs consumption as a function of the prey density. The same occurred with de 3 rd instar predator larvae in all treatments. When daily mean consumption was evaluated the predator/prey ratio was 1:23, 1:27 and 1:33 for 2 nd instar larvae and 1:27, 1:33 and 1:41 for 3 rd instar larvae at 30, 40 and 50 nymph densities, respectively.

Aspectos biológicos de Chrysoperla raimundoi Freitas & Penny (Neuroptera, Chrysopidae)

“…Larvas de C. externa são capazes de consumir diariamente durante o terceiro ínstar cerca de 41,3 de ninfas de Uroleucon ambrosiae (Thomas, 1878) (Hemiptera, Aphididae), importante vetor do vírus-do-mosaico-da-alface, quando oferecidas na densidade de 50 indivíduos (Auad et al 2003). A temperatura é um dos fatores determinantes para o desenvolvimento dos insetos, existindo um gradiente de variação aceitável para cada espécie, necessitando de uma faixa de temperatura ideal para o seu desenvolvimento.…”

Diversidade De Insetos Em Plantas Hospedeiras Próximas Às Áreas De Cultivo De Milho E Algodão

“…Embora também se alimentem nas folhas tem certa preferência pelas hastes floríferas. Ocorrem com frequência nas plantas silvestres da família Asteraceae (AUAD et al, 2003).…”

Effects of Temperature on Development and Survival ofHarmonia axyridis(Coleoptera: Coccinellidae) andChrysoperla externa(Neuroptera: Chrysopidae) Fed onRhopalosiphum padi(Hemiptera: Aphididae)

“…Research findings with predatory coccinellids and lacewings highlight the potential of these agents to control aphids in various crops (Auad et al 2003;Maia et al 2004;Tsaganou et al 2004;Lee & Kang 2004;Barbosa et al 2008;Yu et al 2013), which suggests their use for control of R. padi, given the natural occurrence of predators and prey in pasture (Auad et al 2009). Among predators, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) and Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) are used in augmentative and conservation biological control programs in several crop cultures in various regions of the world (Albuquerque et al 1994;Koch 2003).…”