Orcial Ceolin Bortolotto

Development and reproduction of Spodoptera eridania (Lepidoptera: Noctuidae) and its egg parasitoid Telenomus remus (Hymenoptera: Platygastridae) on the genetically modified soybean (Bt) MON 87701×MON 89788.

Genetically modified crops with insect resistance genes from Bacillus thuringiensis Berliner (Bt-plants) are increasingly being cultivated worldwide. Therefore, it is critical to improve our knowledge of their direct or indirect impact not only on target pests but also on non-target arthropods. Hence, this study evaluates comparative leaf consumption and performance of Spodoptera eridania (Cramer), a species that is tolerant of the Cry1Ac protein, fed with Bt soybean, MON 87701×MON 89788 or its near [corrected] non-Bt isoline. Using this species as a model, we assessed [corrected] the comparative performance of the egg parasitoid Telenomus remus Nixon on eggs of S. eridania produced from individuals that fed on these two soybean genotypes [corrected] as larvae. Results showed that Bt soybean did not affect pest foliage consumption, but did reduce larvel duration by two days despite larvae in both treatments having six instars. Nevertheless, survival of S. eridania larvae, pupal weight, sex ratio, fecundity and longevity of female moths, and egg viability did not differ between Bt and non-Bt soybeans. Adult longevity of S. eridania males was increased when caterpillars were fed with Bt soybean versus the near isoline. No adverse effects of this technology were observed for the egg parasitoid T. remus. [corrected].

No impact of Bt soybean that express Cry1Ac protein on biological traits of Euschistus heros (Hemiptera, Pentatomidae) and its egg parasitoid Telenomus podisi (Hymenoptera, Platygastridae)

No impact of Bt soybean that express Cry1Ac protein on biological traits of Euschistus heros (Hemiptera, Pentatomidae) and its egg parasitoid Telenomus podisi (Hymenoptera, Platygastridae). Biological traits of the stink bug Euschistus heros and its main biological control agent Telenomus podisi were evaluated under controlled environmental conditions (25 ± 2oC; 60 ± 10% RH; and 14/10 h photoperiod) by placing first instar nymphs into Petri dishes with pods originating from two soybean isolines (Bt-soybean MON 87701 × MON 89788, which expresses the Cry1Ac protein, and its near non-Bt isoline A5547) where they remained until the adult stage. Due to gregarious behavior exhibited by first instar nymphs, they were individualized only when at the second instar. Adults were separated by sex and weighed, and pronotum width of each individual was subsequently measured. They were placed into plastic boxes containing soybean grains of the same soybean isoline as food source. Egg viability and female fecundity were assessed in adult individuals. Adult females of T. podisi (up to 24h old) were placed with eggs of E. heros from mothers reared on both soybean isolines. Nymphal development time, insect weight, pronotum width, sex ratio, female fecundity, and egg viability (% emergence) of Euschistus heros did not differ between treatments. Eggto-adult development time, female longevity, sex ratio, and percentage of parasitized eggs were not impacted by the Bt-soybean (expressing Cry1Ac protein). Results indicate that the Bt-soybean, MON 87701 × MON 89788, has no direct significant impact on the two studied species.

Biological characteristics of Heliothis virescens fed with Bt-soybean MON 87701 × MON 89788 and its conventional isoline

This study aimed to evaluate the larval biology of Heliothis virescens in soybean MON 87701 x MON 89788 and its isogenic non-Bt. In general, the impact of soybean MON 87701 x MON 89788 on H. virescens was evidenced in all bioassays, 100% larval mortality, independent of the structure (leaf or pod) consumed by the pest. The small larvae (1st and 3rd instar) demonstrated that they were unable to damage fresh pods of soybean, regardless of whether Bt or not Bt. The large larvae (5th instar) fed on soybean MON 87701 x MON 89788 soybeans consumed three times less compared to larvae fed on non-Bt soybeans, and resulted in reduced longevity and larval survival. When soybean plants were infested with 5th instar larvae, H. virescens caused injuries in the steams of the conventional soybean. It was recorded that the insects moves quickly to this region of the plant. However the soybean MON 87701 x MON 89788 was an effective tool in controlling H. virescens.

Aphidophagous Parasitoids Can Forage Wheat Crops Before Aphid Infestation, Parana State, Brazil

ABSTRACT. Aphid parasitoids are common in Brazilian wheat fields, and parasitize aphids at the wheat tillering stage. However, there is little information available about when this natural enemy occurs in wheat crops. This study investigated the initial occurrence of aphid parasitoids in four commercial wheat crops in northern Paraná during the 2009 crop season. We installed two Malaise traps at each wheat farm, and 400 tillers were assessed weekly in each field for aphid abundance. During this study, we captured 4,355 aphid parasitoids and 197 aphids. Three species of braconid parasitoids were identified, including Aphidius colemani (Viereck 1912), Lysiphlebus testaceipes (Cresson 1880), and Diaeretiella rapae (McIntosh 1855). The aphids species identified were Rhopalosiphum padi (Linnaeus 1758) and Sitobion avenae (Fabricius 1775). This study showed that aphid parasitoids are present in wheat crops even when aphid densities are low, and in one farm, occurred before the aphids colonization. These reports can justified the high efficiency of these natural enemies against aphids in wheat fields.Aphid parasitoids are common in Brazilian wheat fields, and parasitize aphids at the wheat tillering stage. However, there is little information available about when this natural enemy occurs in wheat crops. This study investigated the initial occurrence of aphid parasitoids in four commercial wheat crops in northern Paraná during the 2009 crop season. We installed two Malaise traps at each wheat farm, and 400 tillers were assessed weekly in each field for aphid abundance. During this study, we captured 4,355 aphid parasitoids and 197 aphids. Three species of braconid parasitoids were identified, including Aphidius colemani (Viereck 1912), Lysiphlebus testaceipes (Cresson 1880), and Diaeretiella rapae (McIntosh 1855). The aphids species identified were Rhopalosiphum padi (Linnaeus 1758) and Sitobion avenae (Fabricius 1775). This study showed that aphid parasitoids are present in wheat crops even when aphid densities are low, and in one farm, occurred before the aphids colonization. These reports can justified the high efficiency of these natural enemies against aphids in wheat fields.

Biological Parameters of Podisus nigrispinus (Hemiptera: Pentatomidae) Fed with Different Soybean Insect Pests

ABSTRACT Biological parameters of Podisus nigrispinus (Dallas) fed with third-instar Lepidoptera larvae of Spodoptera frugiperda J.E. Smith, Spodoptera cosmioides (Walker, 1858), and Anticarsia gemmatalis (Hübner, 1818), as well as eggs of Euschistus heros (F., 1798), the brown stink bug, were evaluated. Experiments were performed under controlled conditions (25 ± 1°C; 70 ± 10% relative humidity, and a photoperiod of 16:8 [L:D] h). P. nigrispinus had good nymphal development with >87% larval survival (viability), as well as high fecundity in adults, when fed with A. gemmatalis, S. frugiperda, and S. cosmioides larvae. Differently, adults of P. nigrispinus originating from nymphs fed with eggs of E. heros completed their life cycle; however, larval survival (viability) was reduced to 45.7%. Furthermore, these adults did not oviposit, and their body mass was from 50 to 73% lower than in individuals originating from nymphs fed with other tested prey. Taking into consideration that neither E. heros nor Spodoptera spp. are controlled by Bt soybean varieties expressing the Cry 1Ac protein, it can be assumed that the predator P. nigrispinus will still find prey species to feed in soybean fields even after the adoption of this pest control technology. This might help lower any potential negative impact of Bt soybean adoption above this insect predator. Moreover, the studied caterpillars proved to be potential prey for the predators mass rearing, similarly to what is presently being done with coleopteran larvae.

First report of the microlepidopteran Caloreas cydrota (Meyrick, 1915) (Lepidoptera: Choreutidae) in Brazil

The microlepidopteran Caloreas cydrota (Lepidoptera: Choreutidae) was first time recorded in Colombia in 1915 (Meyrick, 1915), but after it has not been documented in other regions of the world. Among the host plants of Choreutidae belong to the families of Lamiaceae and Boraginaceae, and, to a lesser extent, the families of Umbelliferae, Scrophulariaceae and Moracea (Heppner, 1977; Rota and Miller, 2013 ). However, this family has been poorly studied, with limited information being available about this group of insects (Alipanah, 2008). Therefore, this work presents the first documentation of C. cydrota in Brazil, and is the first to report its association with argentina fleabeane Conyza bonariensis (Linnaeus) (Asteracea).Individual insects were collected from damaged C. bonariensis plants cultivated in a greenhouse at the Embrapa Soybean Research Institution, Londrina, Parana, Brazil. The specimens were collected with the branches during the larval and pupal stages, to avoid any disturbance to the normal development of the insects. After collection, the material was kept in BOD chambers under controlled environmental conditions (25 ± 2 °C temperature, 60 ± 20% humidity, and a 12 h photophase). After the moths emerged, they were killed by freezing (–5 °C) in a freezer for 24 h. Subsequently the material was sent to a specialist at the Uiracu Institute to confirm their identification. The moths were subsequently kept at the entomological museum of the Uiracu Institute.This study presents the first record of the natural occurrence of C. cydrota in Brazil, and in addition, also confirms that C. bonariensis is a host plant of C. cydrota. It is an important report, because until the present, the literature no reports information about plant hosts of this insect. In greenhouse was possible observe that the larvae cause characteristic foliar “folding” in argentine fleabane which then serves as a shelter, damaging the midvein region of the leaf and weave a web. According Aiello and Solis (2003), this behavior represents a camouflage strategy for protection against natural enemies. In addition, C. cydrota larvae caused a superficial damage in the plants by “scraping” the leaf tissue, resulting in a typical brownish appearance of leaves.This injury caused by C. cydrota in argentine fleabeane is important due increase the knowledgement about this insect behavior, and we believe that this report can allow identified this microlepidopteran in other regions. Finally, this study indicates that this insect species might be widespread in other parts of the South America, as C.bonariensis is also common in Uruguay, Paraguay, and Argentina (Vargas et al., 2007).

Development of Dichelops melacanthus and its egg parasitoid Telenomus podisi reared on Bt-soybean MON 87701 x MON 89788 and its near conventional isoline under different temperatures

Dichelops melacanthus was studied under controlled conditions (60 ± 10% RH and 14/10 h L/D photoperiod), and three constant temperatures (19, 25, and 31 ± 2 °C). Fresh pods of MON 87701 × MON 89788 soybeans and its near non-Bt isoline (A5547) were supplied to nymphs and adults. The biology of T. podisi was studied in the same controlled RH conditions, but only at the standard temperature of 25 ± 2 °C. Overall, the development of D. melacanthus was better at higher temperatures, which accelerated the development of the stink bug without affecting adult biological parameters. No influence of Bt-soybeans on the biology of the pest was observed in any temperature studied, which shows that D. melacanthus is not affected by this transgenic soybean. The egg parasitoid T. podisi also was not harmed when it parasitized eggs of the pest fed with MON 87701 × MON 89788 soybeans, with similar results to those obtained in non-Bt isogenic soybeans. Thus, this study demonstrates that D. melacanthus is favored at high temperatures (31 ± 2 °C), and that neither did MON 87701 × MON 89788 soybean pods affect the development of the pest nor its parasitoid T. podisi.