Qualidade de diferentes espécies de pulgões como hospedeiros do parasitóide Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae, Aphidiinae)

Abstract

-Lysiphlebus testaceipes (Cresson) has a broad aphid host range; however the quality of these preys may interfere in its biological feature. This study aimed to evaluate the quality of three Macrosiphini, Brevicoryne brassicae (L.), Lipaphis erysimi (Kaltenbach) and Myzus persicae (Sulzer), and three Aphidini Schizaphis graminum (Rondani) Rhopalosiphum maidis (Fitch) and Aphis gossypii Glover as hosts to L. testaceipes and to determine the relation possible of host preference, of size and quality of the host. The tests were carried out in climatic chamber at 25 ± 1°C, RH 70 ± 10% and 12h photophase. The parasitoid did not oviposite in B. brassicae and L. erysimi, while the other species were nutritionally suitable to the parasitoid. L. testaceipes showed preference for aphids from tribe Aphidini and these hosts presented better quality to the parasitoid when compared to Macrosiphini. Interactions among size, preference and quality between the Aphidini were found. L testaceipes showed preference (parasitism rate 76.7%) for R. maidis, the bigger host (hind tibia with 0.281 mm). This host provided bigger size (hind tibia with 0.49 mm) and higher emergence rate (95.6%) to the parasitoid when compared to A. gossypii (parasitism rate of 55.7%). Also the smaller host A. gossypii (0.266 mm) provided smaller size hind tibia (0.45 mm) and higher mortality of the parasitoid (emergence rate 72.1%). However, the development time was shorter and the longevity was higher in A. gossypii (6.3 and 5.4 days, respectively) when compared to the host R. maidis (6.7 and 3.8 days, respectively), and not been related to host size.KEY WORDS: Development time, biological cycle, host nutritional quality, host size RESUMO -O endoparasitóide solitário Lysiphlebus testaceipes (Cresson) tem uma ampla faixa de afídeos hospedeiros e a qualidade desses afídeos pode interferir nos parâmetros biológicos do mesmo. Este trabalho teve como objetivo avaliar a qualidade de três Macrosiphini, Brevicoryne brassicae (L.), Lipaphis erysimi (Kaltenbach) e Myzus persicae (Sulzer), e três Aphidini, Schizaphis graminum (Rondani), Rhopalosiphum maidis (Fitch) e Aphis gossypii Glover, como hospedeiros de L. testaceipes e determinar a possível relação da preferência do parasitóide com o tamanho e a qualidade do hospedeiro. Os testes foram conduzidos em câmara climática a 25 ± 1°C, 70 ± 10% UR e 12h fotofase. O parasitóide não ovipositou em B. brassicae e L. erysimi e as demais espécies foram adequadas nutricionalmente ao parasitóide. L. testaceipes apresentou preferência por pulgões da tribo Aphidini e esses hospedeiros apresentaram maior qualidade para o parasitóide quando comparados aos Macrosiphini. Foi encontrada relação entre tamanho, preferência e qualidade entre os Aphidini. O parasitóide apresentou preferência (76,7% de parasitismo) por R. maidis, o maior hospedeiro (tíbia posterior de 0,281 mm), e este proporcionou maior tamanho (tíbia posterior de 0,49 mm) e emergência (95,6%) ao parasitóide quando comparado a A. gossypii (55,7% de parasitismo),...

Praon volucre (Hymenoptera: Braconidae: Aphidiinae), a natural enemy of Macrosiphum euphorbiae (Hemiptera: Aphididae): Life table and intrinsic rate of population increase

“…Climatic factors (Rodrigues et al, 2004), nutritional quality (Silva et al, 2008a;Sidney et al, 2010b) and host defences (Brodeur & Boivin, 2004) According to Shukla & Triphathi (1993), climatic conditions, size and host density have a direct influence on the sex ratio of parasitoids and female biased sex ratios are common in Aphidiinae populations.…”

Host plants and aphid hosts influence the selection behaviour of three aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae)

“…The parasitoid L. testaceipes showed a preference and greater acceptance of A. fabae over M. persicae, when they were presented both individually and simultaneously, as well as on both host plants. A. colemani and L. testaceipes are generalists but with preferences for aphids on particular species of plants (Soglia et al, 2006, Silva et al, 2008. It is possible that preimaginal learning, such as contact with the mummy, may have occurred and determined host choice preference (van Emden et al, 2008).…”

Thermal biology and establishment potential in temperate climates of the aphid parasitoid, Lysiphlebus testaceipes

“…Thus, in the event that L. testaceipes are able overwinter in the UK, they could not rely on A. fabae as a host species during this time. Nevertheless, L. testaceipes is known to have an extensive host range (Mackauer and Starý 1967;Starý et al 1988aStarý et al , 2004Silva et al 2008). Therefore as part of the ERA of this population of L. testaceipes, the ability of the parasitoid to successfully parasitize aphids known to overwinter in the UK as mobile stages (anholocyclic clones) was investigated.…”

“…Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae, Aphidiinae), is an important biological control agent for a broad range of aphid species (Starý et al 1988a;Starý et al 2004;Silva et al 2008), including the economically important pest of cereal crops, Schizaphis graminum (Rondani) (Jackson et al 1970;Rodrigues and Bueno 2001). This parasitoid, originally introduced to southern France from Cuba in the 1970s, spread rapidly over Mediterranean France, Italy and Spain (Starý et al 1988a, b).…”

“…Although currently available as a commercial control agent in these regions, L. testaceipes has become a species of renewed interest because of the decision of the joint panel of EPPO (European and Mediterranean Plant Protection Ogranisation) and IOBC (International Organisation for Biological and Integrated Control of Noxious Animals and PlantsWestern Palaearctic Regional Service) to remove it from the EPPO 'positive list' of so called 'safe species' (List of biological control agents widely used in the EPPO region) at the panel meeting in 2008. Factors that led to this decision included a consideration of its wide host range (Starý et al 1988a(Starý et al , b, 2004Silva et al 2008), expanding geographic distribution (Starý et al 2004), and its ability to adapt to and thrive in a range of environments from agro-ecosystems to forests (Starý et al 1988a, b), characteristics which ultimately led to the displacement of native parasitoids (Tremblay 1984;Starý et al 1988bStarý et al , 2004. However, in spite the apparent risks associated with the use of this species as a control agent in southern Europe, under certain conditions the likelihood of such negative effects could be more limited.…”