RESUMO
Ceratitis capitata (Wiedemann, 1824) is an insect of major economic importance in the mango orchards of the submedium of the São Francisco River Valley, the main area of mango production and exportation in Brazil. To provide alternatives for the management of C. capitata, toxic baits based on alpha-cypermethrin (Gelsura®) and spinosad (Success® 0.02 CB) were evaluated in three commercial mango experiments during two consecutive harvests: 2016/2017 (experiment 1 - area 1) and 2017/2018 (experiment 2 -area 2 and experiment 3 - area 3). According to the results, there was a large reduction in the infestation of C. capitata after five sequential applications of the alpha-cypermethrin (6 g.ha-1) and spinosad (0.38 g.ha-1) toxic baits performed at seven-day intervals during mango fruit ripening in all experiments and years (harvest) evaluated. Compared with the untreated plots, the plots with alpha-cypermethrin and spinosad applications showed a significant reduction in the damage induced (fallen fruits and/or on trees) by C. capitata. The management of C. capitata in mango orchards can include the use of the toxic bait based on alpha-cypermethrin, which represents an alternative to rotate with spinosad toxic bait in the São Francisco River Valley.
Assuntos
Ceratitis capitata , Inseticidas , Mangifera , Animais , Inseticidas/farmacologia , Controle de Insetos/métodosRESUMO
Toxic bait formulations have been one of the main strategies used in apple orchards in southern Brazil for the control of South American fruit fly. However, its effects on the stingless bees Plebeia emerina (Friese) and Tetragonisca fiebrigi (Schwarz) are unknown. This study aimed to assess the toxicity, attraction and repellency of food lures and toxic baits on P. emerina and T. fiebrigi. We evaluated the food lures Anamed® (pure), Biofruit® (3%), Flyral® (1.25%), Sugarcane molasses (7%) and Samaritá Tradicional® (3%), in toxic baits formulations associated with spinosad (Tracer® 480SC) and malathion (Malathion® 1000EC), and the ready-to-use toxic baits Success® 0.02CB and Gelsura®. We obtained the mean lethal concentration (LC50) and the mean survival of workers after exposure to toxic bait formulations. In the field, we carried out attraction and repellency tests of toxic baits to foraging. The food lures associated with malathion and spinosad showed different levels of toxicity to P. emerina and T. fiebrigi. Sugarcane molasses and Samaritá Tradicional® associated with spinosad showed high toxicity, with LC50 values of 6.92 and 10.61â¯ng/µL diet to P. emerina, and of 4.37 and 15.48â¯ng/µL diet to T. fiebrigi, respectively. Gelsura® and food lures with malathion caused rapid workers mortality, with mean survival less than 3â¯h after exposure. No toxic bait formulation was attractive to P. emerina foragers in the field. Anamed®, Gelsura®, and Success® were repellent to P. emerina foragers.
Assuntos
Abelhas/efeitos dos fármacos , Controle de Insetos/métodos , Inseticidas/toxicidade , Animais , Abelhas/fisiologia , Brasil , Drosophila , Combinação de Medicamentos , Inseticidas/química , Dose Letal Mediana , Macrolídeos/química , Macrolídeos/toxicidade , Malation/química , Malation/toxicidade , Análise de SobrevidaRESUMO
To provide alternatives to the use of spraying synthetic insecticides in C. capitata management, was evaluated the effect of "attract and kill" toxic baits on population suppression of C. capitata in three commercial areas producing table grapes. Toxic baits of Gelsura™ (4.5 L ha-1) and Success™ 0.02 CB (4.0 L ha-1) resulted in lower population levels of C. capitata adults in monitoring traps after five sequential applications at weekly intervals during the maturation period of the grapes when compared with control plots with or without insecticidal spray. In addition, plots with Gelsura™ and Success™ 0.02 CB applications showed a significant reduction in damage (%) by C. capitata on grape berries and grape bunches when compared with control plots without or with insecticidal spray. However, when compared with a plot treated by conventional management with sprays of etofenprox (Safety™, 100 g c.p. (commercial product) 100 L-1) and applications of spinosad (Success™ 0.02 CB toxic bait) with a brush, only Gelsura™ (4.5 L ha-1) showed a lower level of damage of grape berries and grape bunches. Toxic baits Gelsura™ (4.5 L ha-1) and Success™ 0.02 CB (4.0 L ha-1) are promising alternatives for the population suppression of C. capitata on table grapes.
Assuntos
Ceratitis capitata , Controle de Insetos/métodos , Inseticidas/administração & dosagem , Macrolídeos/administração & dosagem , Piretrinas/administração & dosagem , Vitis/parasitologia , Animais , Combinação de MedicamentosRESUMO
Linepithema micans (Forel) (Hymenoptera: Formicidae) is the main ant species responsible for the spreading of Eurhizococcus brasiliensis (Wille) (Hemiptera: Margarodidae), a soil scale that damages grapevine plants in southern Brazil. The effect of contact and ingestion of insecticides on the control of L. micans was evaluated in a greenhouse using grapevines (Vitis spp.) infested by L. micans. The insecticides thiamethoxam (250, 187.5, and 125 g/ha), fipronil (4, 5, and 50 ml/ha), and imidacloprid (650 g/ha) were sprayed on the ground, whereas toxic baits containing boric acid (0.5, 1.0, and 1.2%), pyriproxyfen (0.3 and 0.5%), and hydramethylnon (0.5%) were evaluated in different formulations. Hydramethylnon (toxic bait) and thiamethoxam (chemical barrier) were the most efficient active ingredients for the control of L. micans.
Assuntos
Formigas , Inseticidas , Animais , Controle de Insetos , Insetos Vetores , Testes de Toxicidade , VitisRESUMO
In southern Brazil, Grapholita molesta (Busck) (Lepidoptera: Tortricidae) uses diapause as survival strategy during the winter (May-August). In our study, we evaluated the effect of diapause on biological characteristics of the species for 4 months in laboratory. Newly hatched larvae of G. molesta were induced to diapause changing the photoperiod and temperature (T) (12 ± 1°C), relative humidity (RH) (70 ± 10%), and a photophase of 12 h and, when they started diapause in the prepupal stage, the conditions were kept for 4 months. Afterwards, the insects were induced to finalize the diapause process at T 25 ± 1°C, RH 70 ± 10%, and a photophase of 16 h. We evaluated the duration and viability of the larval stages and pupae, pupae weight at 24 h and sex ratio (sr), periods of preoviposition, oviposition, and postoviposition; adult life span (males and females); fecundity (daily and total); embryonic period duration and eggs viability, comparing the data with insects nondiapause. The results show that diapause greatly affected the viability of pupal-adult stages of the population (21.8%) when compared with insects' nondiapause (80.0%). Total fecundity (83.0 eggs) and mean life span (12.0 d) of insects diapause was significantly lower compared with insects nondiapause (173.0 and 17.0), respectively. However, these differences were not observed in the sr, which was similar to insects diapause (sr = 0.41) and insects nondiapause (sr = 0.49). The diapause induced for 4 months negatively affects reproduction and life span of adults of G. molesta.
Assuntos
Diapausa de Inseto , Mariposas/fisiologia , Animais , Brasil , Feminino , Larva/crescimento & desenvolvimento , Longevidade , Masculino , Mariposas/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , ReproduçãoRESUMO
Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) is an important plant virus vector in grapevine crops in Brazil and other countries. The mealybug grows in roots and leaves of the grapes. Entomopathogenic nematodes (EPNs) are efficient control agents against insects associated to the soil and could be applied with the same equipment used for chemical insecticides. The aim of this study was to select effective EPNs for controlling P. citri females in laboratory conditions (25±1°C, UR 60±10%). We tested 17 native [Steinernema rarum (6 strains), Steinernema glaseri, Steinernema feltiae, Steinernema riobrave, Steinernema sp., Heterorhabditis bacteriophora (7 strains)] and only one exotic strain (Steinernema carpocapsae ALL). The bioassays were done on Petri dishes infested with females of P. citri, which were sprayed with EPNs juveniles. The strain with larger pathogenicity and virulence in laboratory was H. bacteriophora RS33 (from 69.0% to 92.2% of mortality), native of Rio Grande do Sul.
Assuntos
Insetos Vetores/parasitologia , Controle Biológico de Vetores/métodos , Inseto Planococcus/parasitologia , Rabditídios/patogenicidade , Vitis/parasitologia , Animais , Bioensaio , Brasil , Feminino , Insetos Vetores/virologia , Dose Letal Mediana , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Folhas de Planta/parasitologia , Raízes de Plantas/parasitologia , Vírus de Plantas/fisiologia , Distribuição Aleatória , Virulência , Vitis/virologiaRESUMO
The use of toxic baits has become one of the main methods of management of fruit flies in Brazil. The application of toxic baits may cause side effects on the native parasitoid Doryctobracon areolatus (Hymenoptera: Braconidae). Based on the results, formulations made from the food attractants 3% Biofruit, 1.5% Ceratrap, 1.25% Flyral, 3% Isca Samaritá, 3% Isca Samaritá Tradicional, and 7% sugarcane molasses associated with the Malathion 1000 EC and the ready-to-use toxic bait Gelsura (containing the active ingredient alpha-cypermethrin) were classified as harmful (class 4) to D. areolatus (mortality > 85% at 96 HAE). In contrast, for toxic baits formulated with insecticide phosmet, the mortality ranged from 38% to 72%, classified as slightly harmful or moderately harmful. However, when phosmet was added to the 3% Samaritá Tradicional bait, the mortality was only 3.9% (class 1-harmless), similar to the toxicity observed for the Success 0.02 CB ready-to-use bait (0.24 g a.i. spinosad/l) (<5% mortality). Although toxic baits were formulated with spinosyn-based insecticides, all toxic bait formulations were classified as harmless or slightly harmful (<50% mortality) to D. areolatus, with the exception of 1.5% Ceratrap + spinetoram and 7% Sugarcane molasses + spinosad (≈ 60% mortality-moderately harmful). In addition, these formulations did not show sublethal effects in reducing the parasitism and emergence rate of the F1 generation of D. areolatus in A. fraterculus larvae. The results serve as a basis for the correct use of toxic food baits without affecting the biological control.
Assuntos
Himenópteros , Inseticidas , Fosmet , Tephritidae , Animais , Fosmet/farmacologia , Inseticidas/farmacologia , Malation/farmacologia , Drosophila , Grão ComestívelRESUMO
Our objective was to study the biology and develop a fertility life table for the aphid Chaetosiphon fragaefolli (Cockerell) (Hemiptera: Aphididae) on leaves of strawberry, Fragaria × ananassa, Duchesne ex Rozier (Rosales: Rosaceae), of the cultivars Albion, Aromas, Camarosa, Camino Real, Diamante, Earlibrite, and Saborosa. This study was conducted under controlled conditions: 25 ± 1 (°)C, 70 ± 10% RH, and 12:12 L:D . Arenas were set up consisting of leaves inside Petri dishes containing 3% agar. Female aphids obtained after the last nymphal ecdysis were individually placed in arenas for 24 hours. The following biological parameters were evaluated: duration and survival of the nymph stage and of the life cycle (nymph-nymph), daily and total fecundity, and adult longevity. The aphids completed their biological cycle on all of the cultivars. The shortest durations (in days) of the nymphal stage were on the cultivars Camino Real and Camarosa (8.67 and 8.74 days, respectively), and the longest was on Aromas (11.12 days). The lowest survival was on cultivar Aromas (51%) and the highest on Saborosa (96%). When the time to development to the adult stage was compared, the aphids developed fastest (14.63 days) and survival was highest (96%) on cultivar Saborosa. Aphids reared on cultivar Aromas leaves had the longest pre-reproductive period (8.74 days), the greatest longevity (26.88 days), and the longest duration of the life cycle (19.76 days). Based on the fertility life table, cultivars Camarosa and Saborosa were the most favorable for development of C. fragaefolli, while Albion and Aromas were the most inadequate for aphid development.
Assuntos
Afídeos/fisiologia , Fragaria , Animais , Afídeos/crescimento & desenvolvimento , Fertilidade , Tábuas de Vida , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologiaRESUMO
Studies have demonstrated that the addition of preservatives mixed with food attractants have provided a more expressive attractiveness for fruit fly adults. The objective of the study was to evaluate the capture of Anastrepha fraterculus (Wiedemann, 1830) adults when the addition of borax and/or benzalkonium chloride preservative in BioAnastrephaTM and Isca Samaritá TradicionalTM food attractants compared to CeraTrapTM (control, no preservatives added) in peach orchards. As well as, verifying the effect over non-target insects. BioAnastrephaTM, Isca Samaritá TradicionalTM and CeraTrapTM attractants enabled the capture of A. fraterculus adults when used by themselves in McPhail traps. However, by adding borax and benzalkonium chloride, BioAnastrephaTM and Isca Samaritá TradicionalTM food attractants significantly increased the number of adults captured. Additionally, the number of A. fraterculus adults captured by BioAnastrephaTM attractant + borax was similar to CeraTrapTM attractant over time. Regarding non-target insects, the highest percentages of subjects captured belong to the Coleoptera (4.4 to 11%) and Diptera orders (24.1 to 34.6%) (Drosophilidae family). Nevertheless, insects from the Hymenoptera order [(Formicidae (0.14 to 0.96%), Vespidae (0.02 to 0.3%), and Apidae (0.04 to 0.9%)] families. Neuroptera (0.02 to 0.98%) and Lepidoptera (0.09 to 0.7%) were also captured, although those amounted to less than 1% of the A. fraterculus total. Adding borax and benzalkonium chloride to BioAnastrephaTM and Isca Samaritá TradicionalTM food attractants potentialize the effect of A. fraterculus capture in monitoring traps. Also, adding preservatives made attractants more durable, consequently, the need to replace attractants was not as frequent.
Assuntos
Feromônios/química , Proteínas de Plantas/química , Prunus persica , Tephritidae , Animais , VerdurasRESUMO
Parasitoids of three mealybug pests (Hemiptera: Pseudococcidae), Planococcus ficus (Signoret), Pseudococcus sociabilis Hambleton, and Pseudococcus viburni (Signoret) have been identified for the first time in Brazil. Mealybugs were collected in fruit-growing areas along southern Brazil during 2013-2016. An integrative approach, combining morphological and molecular methods, was used to identify the Brazilian parasitoids to the species level. Fifteen species were recorded, including 14 primary parasitoids belonging to Encyrtidae and Platygastridae and a single secondary parasitoid species belonging to Signiphoridae. The encyrtid parasitoids Acerophagus flavidulus (Brèthes), Anagyrus calyxtoi Noyes and Zaplatycerus sp., and the signiphorid secondary parasitoid Chartocerus axillaris De Santis are reported for the first time in Brazil.
Assuntos
Hemípteros , Himenópteros , Animais , Brasil , Frutas , Hemípteros/parasitologia , Himenópteros/anatomia & histologia , Himenópteros/classificaçãoRESUMO
The larval-pupal endoparasitoid Diachasmimorpha longicaudata (Ashmead, 1905) is considered one of the main biological control agents of fruit flies Ceratitis capitata Wiedemann (1824) and Anastrepha fraterculus Wiedemann (1830) in Central and South America. The application of pesticides for disease and insect-pest management in fruit species may have adverse effects on the parasitoid. The objective of this study was to evaluate the lethal and sublethal effects via residual contact of commercial pesticide formulations on D. longicaudata. The active ingredients thiamethoxam, indoxacarb, chlorpyrifos, deltamethrin, spinetoram, spinosad, phosmet, lambda-cyhalothrin, malathion, dimethoate, and methidationa showed high toxicity to adults (100% mortality) after 96 h and were classified as harmful (Class 4). In contrast, the formulations of azadirachtin (Agroneem 850 EC, Azact 2.4 EC, Azamax 12 EC, and Fitoneem 850 EC), chlorantraniliprole, bordeaux mixture, sulfur, lufenuron, lime sulphur, novalurom, and mancozeb were rated as innocuous (<10% mortality). In addition, the formulations azadirachtin did not reduce the parasitism and the emergence rate of the F0 generation, the same pesticides added to chlorantraniliprole, azadirachtin A+B (Agroneem 850 EC), and lufenuron did not cause reduction in parasitism and emergence rate of the F1 generation of D. longicaudata. The use of pyrethroids, organophosphates, spinosyns, oxadiazines, and neonicotinoids should be used with caution in IPM programs. While pesticides chlorantraniliprole, azadirachtin formulations, bordeaux mixture, lufenuron, lime sulphur, and mancozeb do not cause lethal and sublethal effects for D. longicaudata adults. The results of this study provide important information for use in integrated pest management programs for fruit fly management.
Assuntos
Ceratitis capitata , Himenópteros , Praguicidas , Tephritidae , Vespas , Animais , PupaRESUMO
Anastrepha fraterculus (Wiedemann, 1830) is the main pest of fruit in southern Brazil. The use of toxic baits is one of the alternatives for its management. In this study, the toxic baits Anamed + malathion (10,000 mg/liter), Flyral 1.25% + malathion (2,000 mg/liter), and Gelsura (alpha-cypermethrin, 2,000 and 4,000 mg/liter) were highly toxic to the adults of A. fraterculus (lethal time [LT50] < 7 h). In contrast, Success 0.02 CB had an LT50 of 48.4 h. In the absence of rain, all the formulations had residual effects (>90% mortality) on A. fraterculus adults up to 21 d after treatment (DAT). In the presence of 5, 25, and 50 mm of rainfall, there was a significant reduction in the residual effect over time. However, with up to 50 mm of rain, Anamed + malathion and Gelsura 2,000 and 4,000 mg/liter caused between 43.0 and 79.0% of mortality. In the field, during two consecutive seasons (2015/2016 and 2016/2017), applications of Gelsura 2,000 mg/liter (four applications/season) caused population suppression of the pest throughout the apple fruiting period. However, in the 2016/2017 season, in the area using Gelsura, a higher percentage (≈12%) of apple fruits damaged by A. fraterculus females was observed when compared with the area with insecticide application (damage <3%). The toxic bait Gelsura (2,000 and 4.000 mg/liter) was shown to be promising for use in the management of A. fraterculus, with results similar to those with the application of synthetic insecticides.
Assuntos
Inseticidas , Malus , Tephritidae , Animais , Brasil , Feminino , Frutas , Inseticidas/toxicidadeRESUMO
The use of pesticides is considered one of the most important threats to pollinators, especially since they are widely used in agriculture for pest control. In the last years, several studies have reported severe secondary effects on various bee species, including exotic and native bees. In this study, lethal (mortality) and sublethal (locomotor activity) effects of insecticides and acaricides used in strawberries in Brazil (abamectin, novaluron, spinetoram, and thiamethoxam) were evaluated on the native stingless bees Melipona quadrifasciata and Tetragonisca fiebrigi. The results showed that the effects varied significantly according to the pesticide, type of exposure (oral or topical), and bee species. Through oral exposure, M. quadrifasciata was more susceptible to all insecticides except for abamectin, while in topical exposure, T. fiebrigi was more sensitive. Thiamethoxam followed by spinetoram and abamectin were the most lethal, regardless of species or exposure route; novaluron was not harmful at the highest tested dose. The locomotor activity of bees was altered in the presence of sublethal doses (LC10 and LC50) of all insecticides. Spinetoram and abamectin can be as much as toxic as thiamethoxam against M. quadrifasciata and T. fiebrigi in laboratory experiments. These findings should be confirmed in field experiments to define possibilities to combine pest control and pollinator management. In crops like strawberries, the selectivity of native pollinators should be considered.
Assuntos
Fragaria , Himenópteros , Inseticidas , Animais , Abelhas , Brasil , TiametoxamRESUMO
Biological invasions have reached large parts of the globe, due to human actions across the planet. Drosophila suzukii (Matsumura, 1931) is a globally invasive species, always associated with enormous and costly damage to agricultural crops. Native to Southeast Asia, D. suzukii recently (i.e., 2013) invaded and is dispersing through South America. Here, we used a phylogeographic approach based on the cytochrome c oxidase subunit I gene fragment to explore the invasion dynamics of D. suzukii populations in Brazil. We identified five haplotypes and moderate genetic diversity in Brazilian populations, which are undergoing demographic and spatial expansion. The analyses of molecular variance indicated a high genetic structure among the populations, which is partially explained by their morphoclimatic origin and invasion history. Drosophila suzukii expanded from southern to southeastern Brazil, aided by human-mediated transport of fruits from region to region. The sharing of haplotypes among Brazilian and other invaded regions of the world suggests a single invasion event of D. suzukii in Brazil, originating from previously invaded areas (e.g., North America and Europe). The rapid geographic dispersal and wide variety of fruits attacked by of D. suzukii require immediate implementation of control strategies (legal and phytosanitary) to manage this pest in Brazil.
Assuntos
Drosophila/genética , Distribuição Animal , Animais , Brasil , Variação Genética , FilogeografiaRESUMO
Ceratitis capitata (Wiedemann, 1824) is a significant insect pest of fruits produced worldwide and is capable of causing direct and indirect damage to fruit. Chemical control is the most frequently used management strategy, mainly involving organophosphate insecticides. However, the frequent use of this chemical group has resulted in unacceptable chemical residues on fruits. In this study, the toxicity of 18 insecticides was evaluated in adults and larvae of C. capitata in a laboratory. The organophosphate insecticides chlorpyrifos (Lorsban 480BR), phosmet (Imidan 500WP), and malathion (Malathion 1000EC); the spinosyns spinetoram (Delegate 250WG) and spinosad (Tracer); and the pyrethroid alpha-cypermethrin (Fastac 100SC) caused high mortality (>80%) in C. capitata adults in topical application bioassays and by ingestion when mixed with Biofruit 5% food lures. However, the insecticides chlorfenapyr (Pirate), spinetoram and chlorpyrifos produced a significant reduction in larval infestation of the fruits (67, 74, and 84% larval mortality, respectively). Insecticides based on spinosyns, alpha-cypermethrin, and cyantraniliprole are alternatives that can replace organophosphates in the management of C. capitata in the field.
Assuntos
Ceratitis capitata , Inseticidas , Tephritidae , Animais , Controle de Insetos , Larva , MalationRESUMO
Diachasmimorpha longicaudata (Ashmead, 1905) (Hymenoptera: Braconidae) is considered one of the main biological control agents of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). However, the application of toxic baits for the management of C. capitata might exert side effects on the parasitoid. The objective of this study was to evaluate the side effects of toxic bait formulations on D. longicaudata. The food attractants Anamed, 3% Biofruit, 1.5% CeraTrap, 1.25% Flyral, 3% Isca Samaritá, 3% Isca Samaritá Tradicional, and 7% sugarcane molasses mixed with an organophosphate insecticide [malathion, 2.0 grams of active ingredient (g a.i.) L-1] and the commercial formulation Gelsura (2.0 and 4.0 g a.i. L-1 alpha-cypermethrin) showed high toxicity to D. longicaudata adults (>90% mortality) after 96 h and were thus classified as harmful (Class 4). Similarly, 3% Isca Samaritá Tradicional and 7% sugarcane molasses in formulations with the insecticides spinosad and spinetoram (0.096 g a.i. L-1 or kg) were moderately harmful (Class 3). In contrast, the food attractants Anamed, 3% Biofruit, 1.5% CeraTrap, 1.25% Flyral, and 3% Isca Samaritá Tradicional in combination with spinosad and spinetoram and the formulation Success 0.02CB (0.096 g a.i. L-1 spinosad) were classified as harmless (<10% mortality up to 96 h, Class 1). Additionally, these formulations did not reduce the parasitism and emergence rate of the F1 generation of D. longicaudata in C. capitata larvae. Formulations of toxic baits based on spinosyn are suitable for the management of C. capitata together with the parasitoid D. longicaudata.
Assuntos
Composição de Medicamentos , Himenópteros/efeitos dos fármacos , Inseticidas/química , Inseticidas/toxicidade , Animais , Bioensaio , Controle de InsetosRESUMO
Ceratitis capitata (Wiedemann, 1824) is the main insect pest of fruits worldwide. The objective of this study was to evaluate the toxicity and residual effects of the ready-to-use toxic baits Success 0.02CB (0.24 g of active ingredient [a.i.] per liter of spinosad) and Gelsura (6 g of a.i./liter of alpha-cypermethrin) and to compare them with other food lures containing spinosad and malathion mixed with hydrolyzed protein (Biofruit 5% and Flyral 1.25%), Anamed without dilution or sugarcane molasses (7%) against adult C. capitata in laboratory and greenhouse trials. Ceratitis capitata adults were highly susceptible to all toxic bait formulations (mortality > 80%) until 96 h after exposure. The lowest LT50 (hours) of toxic baits were 2.32 (Gelsura at 4,000 mg/liter), 4.26 (Gelsura at 2,000 mg/liter), 4.28 (Anamed + malathion) and 4.89 (sugarcane molasses + malathion), while formulations containing spinosad (Biofruit, Flyral, Anamed and Success 0.02CB) showed LT50 of approximately 11 h. Without rain, Gelsura (2,000 mg/liter) and all spinosad formulations provided mortality superior to 80% 14 d after application. Gelsura and Anamed + spinosad showed higher resistance to a 5-mm simulated rain, similar to Anamed + malathion, while the other formulations had its efficacy decreased. All toxic baits were effective on adult C. capitata in residual experiments without rain while Anamed + spinosad caused high adult mortality after 5 to 25 mm rains. Gelsura and Anamed + spinosad can be used to replace toxic baits containing malathion for C. capitata population management.
Assuntos
Ceratitis capitata , Inseticidas , Tephritidae , Animais , Combinação de Medicamentos , Controle de Insetos , Macrolídeos , Malation , PiretrinasRESUMO
The mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) has recently been detected in vineyards in southern Brazil. The ant Linepithema micans (Forel) (Hymenoptera: Formicidae) is the most abundant and frequent species in these vineyards, acting mainly as a disperser of the native soil scale, the ground pearl Eurhizococcus brasiliensis (Wille) (Hemiptera: Margarodidae). This study evaluated the interactions (dispersal and predation) of L. micans with P. ficus. The first experiment evaluated the interaction between L. micans and P. ficus in a greenhouse, using Paulsen 1103 rootstock (Vitis berlandieri × Vitis rupestris) planted in pots. Plants were infested by 1) adult females of P. ficus, and 2) adult females of P. ficus and L. micans, and all mealybugs remaining after the experimental period were counted. To evaluate P. ficus predation by L. micans, two laboratory experiments were conducted (25°C, 80% relative humidity). In the first experiment, sprouted potatoes were infested with ovisacs, first-instar nymphs and adult females of P. ficus and evaluated in three treatments: 1) L. micans fed with carbohydrate and protein, 2) L. micans without food, and 3) without ants present. In the second, potatoes were infested only with first-instar nymphs of P. ficus and were exposed in two treatments: 1) L. micans without food, and 2) without ants present. The results were evaluated by counting the remaining mealybugs, with and without ants. The results showed that L. micans does not transport P. ficus, and predates on first-instar nymphs of the mealybug.
Assuntos
Distribuição Animal , Formigas , Hemípteros , Comportamento Predatório , Animais , Feminino , VitisRESUMO
BACKGROUND: Drosophila suzukii is a primary insect pest that causes direct damage to fruits with a thin epidermis such as strawberries, cherries and blueberries. In strawberry fields, the co-occurrence of D. suzukii and Zaprionus indianus has increased production losses. This study evaluated the toxicities and effects of insecticidal baits to control adults and larvae of both D. suzukii and Z. indianus. RESULTS: Organophosphate (dimethoate and malathion), spinosyn (spinosad and spinetoram), pyrethroid (lambda-cyhalothrin) and diamide (cyantraniliprole) insecticides exhibited high toxicity to both adults and larvae of D. suzukii and Z. indianus (mortality >80%) in topical and dip bioassays. However, when the insecticides were mixed with a feeding attractant, a positive effect was observed only for adults of D. suzukii. Insecticides containing neonicotinoids (acetamiprid and thiamethoxam) and pyrolle (chlorfenapyr) caused intermediate mortality to adults of D. suzukii (40-60%) and low mortality for Z. indianus (mortality <23%); however, these compounds reduced the larval infestation of the two species by 55-86%. Botanical (azadirachtin) and sulphur insecticides exhibited low toxicity (mortality <40%) on adults and larvae of both species. CONCLUSION: Dimethoate, malathion, spinosad, spinetoram, lambda-cyhalothrin and cyantraniliprole are highly toxic to both larvae and adults of D. suzukii and Z. indianus. The use of toxic baits for adults of D. suzukii could be an alternative in management of this species. © 2016 Society of Chemical Industry.
Assuntos
Drosophila , Inseticidas , Animais , Combinação de Medicamentos , Controle de Insetos/métodos , Larva , Macrolídeos , Organofosfatos , Pirazóis , Piretrinas , ortoaminobenzoatosRESUMO
The Serra Gaúcha region is the most important temperate fruit-producing area in southern Brazil. Despite mealybugs (Hemiptera: Pseudococcidae) infesting several host plants in the region, there is a lack of information about the composition of species damaging different crops. A survey of mealybug species associated with commercial fruit crops (apple, persimmon, strawberry and grapes) was performed in Serra Gaúcha between 2013 and 2015, using both morphology and DNA analyses for species identification. The most abundant species were Pseudococcus viburni (Signoret), found on all four host plant species, and Dysmicoccus brevipes (Cockerell), infesting persimmon, vines and weeds. The highest diversity of mealybug species was found on persimmon trees, hosting 20 different taxa, of which Anisococcus granarae Pacheco da Silva & Kaydan, D. brevipes, Pseudococcus sociabilis Hambleton and Ps. viburni were the most abundant. A total of nine species were recorded in vineyards. Planococcus ficus (Signoret) and Pseudococcus longispinus (Targioni Tozzetti) were observed causing damage to grapes for the first time. A single species, Ps. viburni, was found associated with apples, while both Ps. viburni and Ferrisia meridionalis Williams were found on strawberry. Four of the mealybug species found represent new records for Brazil.