Browsing by Issue Date, starting with "2001-08"
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- Effects of conventional pesticides on the preimaginal developmental stages and on adults of Trichogramma cordubensis (Hymenoptera: Trichogrammatidae).Publication . Vieira, António; Oliveira, Luísa; Garcia, PatríciaThe effects of seven pesticides sprayed on hosts with parasitoids at different phases of egg to adult development (24, 24± 48, 48± 72, 72± 96, 120± 144, 192± 216 h) of Trichogramma cordubensis (Vargas & Cabello) were studied. The effect of these pesticides on the mortality of adult parasitoids upon contact with the hosts immediately or 24 h after the treatments was also tested. One organophosphate insecticide (trichlorfon), one organochlorine insecticide (endosulfan), two pyrethroids (deltamethrin and lambda-cyhalothrin), a commercial formulation of Bacillus thuringiensis subsp. Kurstaki, and two fungicides (acetamide + dithiocarbamete and basic copper sulphate) were selected for testing. All the tests were carried out with fresh solutions of commercial insecticides applied on host eggs at the recommended concentration. The pesticides applied at different development phases did not affect the duration of parasitoid development, except endosulfan, which delayed the parasitoid preimaginal development for one day. With few exceptions, the number of parasitized host eggs that turned black (i.e. with parasitoid prepupae) did not differ significantly between the pesticide treatments and the control. The chemical insecticides affected the adult emergence rates significantly, while the other products resulted in emergence rates similar to control values. The longevity of adult progeny was very short when endosulfan or trichlorfon (< 1 and < 2 days, respectively) were applied. Overall, endosulfan was the pesticide most harmful to the preimaginal development stages of T. cordubensis. Therefore, the use of this product should be avoided when this species is part of an integrated pest control programme.
- The Azores Islands: A Unique Location for Ground-Based Measurements in the MBL and FT of the Central North Atlantic.Publication . Honrath, Richard; Fialho, PauloThe Azores Islands - the only islands in the central North Atlantic that are distant from all surrounding continentes - have historically been important for studies of the North Atlantic atmosphere. Prior to the advent of satellite observations, they provided weather data critical to the accuracy of forecasts of European weather. Today, they provide a unique base for observations of the impacts on atmospheric composition of emissions from the surrounding continents. As part of the NARE program, ground-based measurements of CO and O3 [Parrish et al., 1998] and NOY [Peterson et al., 1998], as well as ozone sondes [Oltmans et al., 1996] were made in 1993 on the island of Terceira. The Azores have also served as a base for airborne studies (e.g., those described by Law et al., this issue) and shipboard studies [e.g., Huebert et al., 1996]. Here, we briefly discuss Azores ground-based measurements, with an emphasis on a new mountaintop site designed to probe the free troposphere. […].
- Life history studies and ecological observations of Endarachne binghamiae J. Agardh (Scytosiphonaceae, Phaeophycota) from the Azores.Publication . Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.
- On the occurrence of the genus Sebdenia (Halymeniales, Rhodophyta) in the Azores.Publication . Neto, Ana I.; Terra, Marlene R.
- Checklist of the Benthic Marine Plants of the Madeira Archipelago.Publication . Neto, Ana I.; Cravo, D. C.; Haroun, R. T.A checklist of the benthic marine plants of the archipelago of Madeira is presented based on published information and personal observations. This list includes 1 Spermatophyte and 359 algal species, comprising 64 Chlorophycota, 64 Chromophycota and 231 Rhodophycota. Fifteen doubtful records for the area are also included.