Browsing by Author "Cabral, Susana"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Effects of deltamethrin on the reproduction of Trichogramma cordubensis (Hymenoptera: Trichogrammatidae)Publication . Garcia, Patrícia; Cabral, Susana; Oliveira, Luísa; Rodrigues, ArmindoThe influence of deltamethrin on the reproduction of Trichogramma cordubensis, a thelytokous egg parasitoid, was investigated by studying egg maturation and daily fecundity of insecticide treated wasps and offspring emergence rates. The insecticide was applied to the parasitoids at the prepupal stage within its host eggs (Ephestia kuehniella ). The total number of parasitized eggs per female during the first 7 days was not significantly influenced by the tested concentrations of deltamethrin. Prevalence of parasitism during this period had a similar pattern between deltamethrin treatments and the control. In addition, the mean number of mature eggs observed per female per day was significantly correlated to mean daily fecundity, regardless of the treatments. Offspring emergence was significantly influenced by the insecticide treatments experienced on their progenitors, decreasing significantly at 48 and 72 h for the highest tested concentration of deltamethrin (23.6 mg [a.i.]/L). Despite that, deltamethrin had no adverse effects on the reproduction of treated wasps, particularly when was applied at the concentration recommended by the manufacturer (12.5 mg [a.i.]/L).
- Essential and non-essential trace metals in scalp hair of men chronically exposed to volcanogenic metals in the Azores, PortugalPublication . Amaral, André; Arruda, Mónica; Cabral, Susana; Rodrigues, ArmindoVolcanoes produce and release large amounts of toxicants, and the concentration of metals in hair can be used as a biomarker of exposure to trace metals. In order to investigate whether humans exposed to volcanic emissions demonstrate higher concentrations of essential and non-essential trace metals, scalp hair of men (3–89 years) living in two areas of the Azores, one exposed to volcanic emissions and the other not, was sampled, and their content in Cd, Cu, Pb, Rb, Se, and Zn was quantified by using High Resolution Inductively Coupled Plasma Mass Spectrometry. In average, men exposed to volcanic emissions presented higher concentrations of Cd (96.9 ppb), Cu (16.2 ppm), Pb (3417.6 ppb), Rb (216.3 ppb), and Zn (242.8 ppm), but not Se (469.6 ppb). Also, strong and significant correlations were found between Cd–Rb and Pb–Rb in the exposed men. In conclusion, humans living chronically exposed to volcanic emissions show high concentrations of essential and non-essential trace metals in scalp hair, and is suggested that this type of exposure may be as harmful as living close to industrial facilities.
- New records of Coccinellidae (Coleoptera) to the Azores islandsPublication . Soares, António O.; Borges, Isabel; Cabral, Susana; Figueiredo, Helena; Resendes, RobertoIn order to record new Coccinellidae species to the Azores, forty one samplings were made in S. Miguel, Graciosa and Pico islands. Graciosa and Pico islands surveys were performed during the scientific expeditions organised by the Department of Biology from the University of the Azores, between the 7th and 15th of June, 2004 and the 6th and 15th of June, 2005, respectively. A total of eleven species were collected. The presence of two new species was noticed: one Scymnini species to Pico island, Clitosthetus arcuatus (Rossi) and one Coccinellini species to S. Miguel island, Myrrha octodecimguttata (Linnaeus).
- Voracity of Coccinella undecimpunctata: effects of insecticides when foraging in a prey/plant systemPublication . Cabral, Susana; Soares, António O.; Garcia, PatríciaCoccinella undecimpunctata L. is a euryphagous predator established in Azores that offers interesting potential as a control agent in the context of integrated pest management (IPM). However, to further develop IPM against aphids, it is important to evaluate the effects that insecticides might have on voracity. Thus, we proposed to evaluate the effects of pirimicarb and pymetrozine on the voracity of 4th instar larvae and adults of C. undecimpunctata, under distinct scenarios of exposure to chemicals within a prey/plant system. Voracity of C. undecimpunctata was not significantly affected by pirimicarb or pymetrozine when treatments were directly sprayed on the predator; however, when insecticides were sprayed on the prey/plant system, the predator’s voracity was significantly increased. Results suggest that C. undecimpunctata does not detect the insecticide on the aphids and indicate that the increase in voracity may be due to a decrease in the mobility of insecticide-treated aphids, since their capture should be easier than highly mobile non-treated prey. The consequences of such increase in the voracity for IPM programs are discussed.