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1.
An. acad. bras. ciênc ; 89(4): 2955-2969, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-886855

ABSTRACT

ABSTRACT The host acceptance behavior and environmental factors as temperature affect the feeding behavior of Lepidoptera pests. Thus, they must be considered in studies about the risk potential of resistance evolution. The current study sets the differences in the feeding behavior of neonate Alabama argillacea (Hübner) (Lepidoptera: Noctuidae) larvae exposed to Bt and non-Bt cotton plants, under different temperatures and time gap after hatching. Two cotton cultivars were used: the Bt (DP 404 BG - bollgard) and the non-transformed isoline, DP 4049. We found that the feeding behavior of neonate A. argillacea is significantly different between Bt and non-Bt cotton. Based on the number of larvae with vegetal tissue in their gut found on the plant and in the organza as well as on the amount of vegetal tissue ingested by the larvae. A. argillacea shows feeding preference for non-Bt cotton plants, in comparison to that on the Bt. However, factors such as temperature and exposure time may affect detection capacity and plant abandonment by the larvae and it results in lower ingestion of vegetal tissue. Such results are relevant to handle the resistance of Bt cotton cultivars to A. argillacea and they also enable determining how the cotton seeds mix will be a feasible handling option to hold back resistance evolution in A. argillacea populations on Bt cotton, when it is compared to other refuge strategies. The results can also be useful to determine which refuge distribution of plants is more effective for handling Bt cotton resistance to A. argillacea.


Subject(s)
Animals , Temperature , Gossypium/parasitology , Feeding Behavior/physiology , Lepidoptera/physiology , Biological Assay , Pest Control, Biological , Plants, Genetically Modified , Gossypium/genetics , Lepidoptera/classification
2.
Braz. j. biol ; 76(3): 787-795, tab, graf
Article in English | LILACS | ID: lil-785051

ABSTRACT

Abstract Thirty-one morphotypes of insect galls and two flower damages were found on 16 families, 22 genera and 24 plant species in Restinga de Marambaia (Barra de Guaratiba, Rio de Janeiro, RJ). Fabaceae and Myrtaceae were the plant families with the greatest richness of insect galls (4 and 6 morphotypes, respectively), and the greatest number of galled plants (four and three species, respectively). Galls were mostly found on leaves and stems (77% and 10%, respectively). The galling insects are represented by Diptera, Lepidoptera, and Hemiptera. The majority of the galls (81%) were induced by gall midges (Cecidomyiidae: Diptera).


Resumo Foram encontrados 31 morfotipos de galhas de insetos e dois danos em flores em 16 famílias, 22 gêneros e 24 espécies de plantas, na Restinga de Marambaia (Barra de Guaratiba, Rio de Janeiro, RJ). Fabaceae e Myrtaceae foram as famílias de plantas com maior riqueza de galhas (4 e 6 morfotipos, respectivamente) e maior número de espécies com galhas (quatro e três espécies, respectivamente). As galhas predominaram nas folhas e caules (77% e 10%, respectivamente). Os insetos galhadores estão representados por Diptera, Lepidoptera e Hemiptera. A maioria das galhas (81%) foi induzida por Cecidomyiidae (Diptera).


Subject(s)
Animals , Plant Tumors/parasitology , Plants/parasitology , Host-Parasite Interactions/physiology , Insecta/physiology , Plant Tumors/classification , Brazil , Plant Stems/parasitology , Plant Leaves/parasitology , Myrtaceae/parasitology , Diptera/classification , Diptera/physiology , Hemiptera/classification , Hemiptera/physiology , Insecta/classification , Fabaceae/parasitology , Lepidoptera/classification , Lepidoptera/physiology
3.
Braz. j. biol ; 76(2): 307-314, Apr.-June 2016. tab
Article in English | LILACS | ID: lil-781385

ABSTRACT

Abstract Mass production of predatory stinkbugs in the laboratory is prioritized to release them into the field as part of IPM programs. Therefore, the aim of this study was to identify the best prey for rearing the predator Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae) among five different species of insect (three of Lepidoptera, one of Coleoptera, and one of Diptera). Second-instar P. nigrispinus nymphs were conditioned in transparent 1000-mL plastic pots, adults were placed in Petri dishes for mating, and both stages were maintained under controlled conditions (25 ± 1°C, 12 hours of photophase, 70 ± 10% RH). Nymphs and adults of P. nigrispinus consumed more Musca domestica (Linnaeus, 1758) (Diptera: Muscidae) larvae than the other tested prey. The consumption of fly larvae was 1.5 larvae/day/nymph and adults 1.7 larvae/day/adult. However, the number of eggs per female was less when the predator consumed M. domestica larvae (407.8 eggs/female) and most when consumed the Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) larvae (797.7 eggs/female). Furthermore, the percentage of hatched eggs was greater when the predator females consumed D. saccharalis larvae (90.0%). D. saccharalis larvae is the best prey to rearing P. nigrispinus.


Resumo A produção massal de percevejos predadores no laboratório é priorizada para liberá-los no campo, como parte de programas de MIP. Portanto, o objetivo deste estudo foi identificar a melhor presa para a criação do predador Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae) entre cinco espécies diferentes de insetos (três de Lepidoptera, uma de Coleoptera e uma de Diptera). Ninfas de segundo ínstar de P. nigrispinus foram acondicionadas em recipientes plásticos transparentes de 1000 ml, adultos foram colocados em placas de Petri para o acasalamento e, ambos os estágios foram mantidos sob condições controladas (25 ± 1°C, fotofase de 12 horas e 70 ± 10% UR). Ninfas e adultos de P. nigrispinus consumiram mais larvas de Musca domestica (Linnaeus, 1758) (Diptera: Muscidae) do que as outras presas testadas. O consumo de larvas de mosca foi de 1,5 larvas/dia/ninfa e adultos 1,7 larvas/dia/adulto. No entanto, o número de ovos por fêmea foi menor quando o predador consumiu larvas de M. domestica (407,8 ovos/fêmea) e maior quando consumiu larvas de Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) (797,7 ovos/fêmea). Além disso, a percentagem de eclosão de ninfas foi maior quando as fêmeas do predador consumiram larvas de D. saccharalis larvas (90,0%). Larvas de D. saccharalis é a melhor presa para a criação de P. nigrispinus.


Subject(s)
Animals , Female , Sexual Behavior, Animal/physiology , Coleoptera/physiology , Food Chain , Hemiptera/physiology , Lepidoptera/physiology , Reproduction/physiology , Diptera/physiology , Life Cycle Stages/physiology
4.
Braz. j. biol ; 74(1): 205-211, 2/2014. tab
Article in English | LILACS | ID: lil-715597

ABSTRACT

We studied the biology of Tiracola grandirena (Herrich-Schäffer, 1868) (Lepidoptera: Noctuidae: Hadeninae) at 25 ± 1 °C, 70 ± 10% RH and 14 hours of photo phase. Three experiments, using 150 larvae each, were conducted for the larval stage. In the first, used to assess the duration and survival of all stages, insects were reared individually and fed an artificial diet (Grenee). In the second, individuals were also reared separately, but were fed leaves of 10 plants from different families. In the third, the larvae were not individualised, the food plants were rotated such as to provide three plant species every 48 hours. In the first experiment, the viability of the eggs, larvae, pupae and prepupae was 91.9, 94.7, 32.49 and 43.5%, respectively. The average duration of the egg, larvae, prepupae, pupae and adult were 6.0, 25.3, 25.7, 21.4 and 12.7 days, respectively. The prolonged prepupal period indicates that T. grandirena can develop larval (prepupal) diapause. The results of the experiments with different host plants showed that T. grandirena is polyphagous at species, population and individual level.


Estudou-se a biologia de Tiracola grandirena (Herrich-Schäffer, 1868) (Lepidoptera: Noctuidae: Hadeninae) em condições controladas de 25 ± 1 °C, 70 ± 10% UR e fotofase de 14 horas. Na fase larval foram estabelecidos três experimentos empregando 150 larvas cada. No primeiro, os insetos foram criados individualmente, com dieta artificial de Grenee, cujos dados foram utilizados para avaliar a duração e a sobrevivência das larvas, pupas e adultos. No segundo, as larvas foram criadas individualmente, alimentadas com folhas de 10 plantas de famílias diferentes avaliando-se a sobrevivência e duração larval (fase ativa). No terceiro, as larvas foram mantidas em um mesmo recipiente, variando-se a alimentação vegetal, três espécies a cada 48 horas, avaliando-se apenas a sobrevivência larval. No primeiro experimento a viabilidade de ovo, larva, pré-pupa e pupa foi de 91,93; 94,67; 32,39 e 43,48%, respectivamente. A duração média de ovo, larva, pré-pupa, pupa e adulto foi de 6,00; 25,26; 25,76; 21,35 e 12,67 dias, respectivamente. O prolongado período de pré-pupa indicou que, nas condições em que foi criada T. grandirena pode desenvolver diapausa larval (pré-pupal). Os resultados dos experimentos com diferentes plantas hospedeiras demonstraram que T. grandirena é polífaga ao nível específico, populacional e individual.


Subject(s)
Animals , Female , Male , Lepidoptera/physiology , Life Cycle Stages/physiology , Larva/growth & development , Lepidoptera/classification , Lepidoptera/growth & development , Survival Analysis
5.
Braz. j. biol ; 73(1): 179-184, Feb. 2013. ilus
Article in English | LILACS | ID: lil-671377

ABSTRACT

The larvae of the southern beet webworm Herpetogramma bipunctalis (Fabricius, 1794) damage the leaves of species in the plant genus Rubus. The present study investigated the biology of H. bipunctalis and developed a protocol for raising H. bipunctalis under laboratory conditions. On the basis of the biological data, we devised a life table. In order to develop the rearing procedures, we determined which oviposition substrate and blackberry cultivar were the most appropriate for larval development. The mean durations of the egg, larval, and pupal stages were 5.59 days, 26.37 days, and 13.37 days, respectively, and the corresponding survival rates were 80.83%, 49.07%, and 83.23%. The mean pupal weight was 0.0491 g for males and 0.0536 g for females. The mean life cycle (egg-to-adult) period was 45.33 days, and overall survival to adulthood was 33.01%. H. bipunctalis females laid a mean of 252.63 eggs over a mean of 13.60 days of oviposition; the mean pre-oviposition period was 2.67 days. Mean female and male life spans were 17.51 and 19.25 days, respectively, and the sex ratio was 0.51. The life-table data indicated that H. bipunctalis can reproduce 57.9 times per generation. Each cage contained one blackberry leaf placed on a paper towel. This method allowed us to obtain the greatest number of eggs. The larval stage was shorter for insects reared on leaves of the Guarani cultivar than for those reared on leaves of the Xavante cultivar (22.63 vs. 26.37 days). These basic data can aid in establishing strategies for the management of H. bipunctalis on blackberry farms.


Lagartas de Herpetogramma bipunctalis (Fabricius, 1794) causam danos nas folhas da amoreira-preta (Rubus spp.). O objetivo deste trabalho foi estudar sua biologia e desenvolver uma técnica de criação, em condições de laboratório. Com os dados de biologia, foi elaborada uma tabela de vida de fertilidade. Para o estudo da técnica de criação, foram determinados o substrato para obtenção de ovos e a cultivar de amoreira-preta mais adequada para o desenvolvimento larval. A duração dos estágios de ovo, lagarta e pupa foram de 5,59, 26,37 e 13,37 dias, com sobrevivência de 80,83, 49,07 e 83,23%, respectivamente. O peso das pupas foi 0,0491 g para machos e 0,0536 g para fêmeas. O ciclo biológico (ovo-adulto) foi de 45,33 dias, com sobrevivência total de 33,01%. As fêmeas colocaram, em média, 252,63 ovos durante 13,60 dias, com um período de pré-oviposição de 2,67 dias. A longevidade média de fêmeas e machos foi de 17,51 e 19,25 dias, respectivamente, e a razão sexual, de 0,51. Por meio da tabela de vida de fertilidade, determinou-se uma capacidade de aumento de 57,9 vezes a cada geração. Gaiolas revestidas com papel toalha e com a presença de folhas de amoreira-preta propiciaram a obtenção de uma maior quantidade de ovos. A duração do estágio larval para os insetos alimentados com folhas de amoreira-preta cv. Guarani (22,63 dias) foi menor do que aqueles alimentados com folhas da cv. Xavante (26,37 dias). Estas informações são básicas e auxiliarão em futuros estudos, visando ao estabelecimento de estratégias de manejo de H. bipunctalis em amoreira-preta.


Subject(s)
Animals , Female , Male , Lepidoptera/growth & development , Plant Leaves/parasitology , Rosaceae/parasitology , Lepidoptera/physiology , Life Cycle Stages/physiology , Oviposition/physiology , Reproduction/physiology , Sex Ratio
6.
Neotrop. entomol ; 40(2): 251-257, Mar.-Apr. 2011. graf, tab
Article in Spanish | LILACS | ID: lil-586664

ABSTRACT

The objective of this research was to evaluate the incidence of damage by the leafworm Alabama argillacea (Hübner) on yields of cotton grown under rows spaced 0.38 m and 0.76 m at the irrigation area of Santiago del Estero, Argentina. The period evaluated was extended from first flower to first open boll. Treatments were T1 - without control of larvae, T2 - with control of larvae, T3 - control since first flower to the end of effective blooming, and T4 - with larval control since the end of effective blooming to first open boll. The effect of injuries on the crop was evaluated trough boll cotton yield. Larvae were sampled in a weekly basis and insects were present from the first flower until harvest. Populations of A. argillacea decreased crop yields in the two distances tested, by decreasing the weight or number of open bolls.


Subject(s)
Animals , Gossypium/parasitology , Lepidoptera/physiology , Agriculture/methods
7.
Arq. Inst. Biol. (Online) ; 78(1): 81-87, jan-mar, 2011. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1396327

ABSTRACT

Trichogramma spp. (Hymenoptera: Trichogrammatidae) parasitam ovos de Anticarsia gemmatalis (Lepidoptera: Noctuidae), o principal desfolhador de soja no Brasil. O objetivo deste trabalho foi avaliar o parasitismo de onze espécies/linhagens de Trichogramma em cartelas de cartolina com vinte ovos de A. gemmatalis por fêmea desse parasitoide durante 24 horas. A linhagem de Trichogramma atopovirilia (Hymenoptera: Trichogrammatidae) de Sete Lagoas, Minas Gerais, apresentou melhor desempenho com 19 ovos de A. gemmatalis parasitados por fêmea em 24 horas, viabilidade de 98% e razão sexual de 0,84. A linhagem de Trichogramma pretiosum de Cristalina, Goiás, parasitou 11,9 ovos de A. gemmatalis por fêmea com 98% de viabilidade e razão sexual de 0,65. Esse trabalho confirma a importância de se avaliar linhagens de Trichogramma antes de programas de controle biológico, pois diferentes linhagens de uma mesma espécie desse parasitoide apresentam resultados distintos.


Several Trichogramma (Hymenoptera: Trichogrammatidae) species parasitize Anticarsia gemmatalis (Lepidoptera: Noctuidae) eggs, the major soybean desfoliator in Brazil. The objective of this work was to evaluate the parasitism of eleven Trichogramma species/strains in cardboards with twenty eggs of A. gemmatalis by this parasitoid female for 24 hours. The strain trat - 2 Trichogramma atopovirilia (Hymenoptera: Trichogrammatidae) of Sete Lagoas, Minas Gerais, showed better performance with 19 A. gemmatalis eggs parasitized by female in 24 hours, 98% viability and sex ratio of 0.84. The strain Trichogramma pretiosum of Crystalline, Goiás, parasitized 11.9 A. gemmatalis eggs per female with 98% viability and sex ratio of 0.65. This work confirms the importance of evaluating Trichogramma strains before biological control programs, because different strains of the same species of parasitoid have distinct results.


Subject(s)
Soybeans/parasitology , Pest Control, Biological/methods , Hymenoptera , Lepidoptera/physiology
8.
Neotrop. entomol ; 40(1): 152-153, Jan.-Feb. 2011.
Article in English | LILACS | ID: lil-578852

ABSTRACT

The presence of Stigmella epicosma (Meyrick) is reported for the first time from two coastal valleys from northern Chile: Azapa and Chaca. Adults examined were reared from leafminer larvae on Trixis cacalioides (Asteraceae), the first host plant known for S. epicosma.


Subject(s)
Animals , Asteraceae/parasitology , Lepidoptera/physiology , Chile , Demography
9.
Neotrop. entomol ; 40(1): 14-19, Jan.-Feb. 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-578853

ABSTRACT

Rearing Technique and Biological Traits of Atheloca subrufella (Hulst) (Lepidoptera: Phycitidae) in Coconut Fruits. Larvae of the coconut moth Atheloca subrufella (Hulst) develop in flowers and fruits of coconut, Cocos nucifera, causing precocious abscission of these structures and, hence, yield decrease. This work studied a feasible and suitable rearing technique for A. subrufella using fruits of coconut. We first determined the appropriate density of larvae to be reared per coconut fruit (among two, three, four or five larvae) and later tested the suitability of this rearing technique for three successive generations. The storage of egg and pupal stages during 0, 5, 10 and 20 days was also studied at 12ºC. Based on the fertility life table parameters, the best results were achieved by rearing two or three larvae per fruit as they yielded the best net reproductive rate and intrinsic rate of population increase. In addition, eggs and pupae of A. subrufella can be stored at 12ºC up to five days with viability higher than 90 percent. Adult moths emerged from pupae stored for five days at 12ºC produced an average of 219.4 eggs and lived 18.8 days. Storage periods for eggs and pupae over 10 days significantly reduced egg viability and adult fecundity, respectively. Thus, the technique in here described was shown to be suitable for the continuous rearing of A. subrufella in laboratory conditions.


Subject(s)
Animals , Lepidoptera/growth & development , Cocos , Entomology/methods , Larva , Lepidoptera/physiology
10.
Neotrop. entomol ; 39(5): 681-685, Sept.-Oct. 2010. graf
Article in Portuguese | LILACS | ID: lil-566201

ABSTRACT

Herbivorous insects may attack eucalyptus causing economic losses. One of these pests is the moth Euselasia apisaon Dahman, a key pest in the basin of middle Rio Doce. Here we studied the survival of pupae of this moth in Eucalypts and in understorey plants and tested the hypotheses: i) live pupae are more abundant in plants of the understorey than in eucalyptus, ii) there is no difference between the abundance of pupae in different plants of the understorey. We sampled three areas cultivated with eucalyptus in Belo Oriente, MG, and samples were taken in five plots each area, getting five branches of each plant and of five eucalyptus trees that bordered the plot. The proportion of live and dead pupae and the mortality rate were estimated. The abundance of live pupae was higher in the understorey and the mortality rate of pupae was the same among different families of plants of the understorey. It is possible the larger available leaf area of understorey plants justify the greater abundance of live pupae in this habitat, however, avoidance of feeding habitat to finish the life cycle is also a possible explanation. Mortality rate in plants of the understorey points to an equal pressure of natural enemies on the pupae. These appointments help us to understand the dynamics of pests in eucalyptus plantations, providing important information to support actions against pests in natural environments.


Subject(s)
Animals , Eucalyptus/parasitology , Lepidoptera/physiology , Brazil , Pupa
11.
Neotrop. entomol ; 39(4): 543-548, July-Aug. 2010. graf
Article in Portuguese | LILACS | ID: lil-558839

ABSTRACT

The effects of increasing plant diversity on the population of the coffee leaf-miner Leucoptera coffeella (Guérin-Mèneville) were investigated in two organic coffee production systems. One system consisted of coffee intercropped with banana trees (shaded system) and the other one of coffee intercropped with pigeon pea (unshaded system). The increase in plant diversity on both systems was achieved via introduction of green manures such a perennial pea nut, sunn hemp and Brazilian lucerne. The population of L. coffeella, predation and parasitism of L. coffeella mines were biweekly evaluated during eight months. The increase in plant diversity on both systems did not affect the attack of L. coffeella on coffee leaves and the mine parasitism rate. However, there was a positive and significant relationship between increasing plant diversity and coffee leaf mine predation by wasps on unshaded coffee system and a negative relationship on shaded coffee system.


Subject(s)
Animals , Coffea/parasitology , Lepidoptera/physiology , Plant Leaves/parasitology
12.
Neotrop. entomol ; 39(4): 618-625, July-Aug. 2010. graf, tab
Article in English | LILACS | ID: lil-558851

ABSTRACT

The susceptible species Cedrela odorata and Swietenia macrophylla to attack by Hypsipyla grandella (Zeller) larvae were grafted onto the resistant species Khaya senegalensis and Toona ciliata. Six-month-old grafted plants were then compared to their reciprocal grafts and to both intact (non-grafted) and autografted plants for damage due to H. grandella larvae and for their effects on larval performance. Two experiments were conducted: one in which the apical bud of the main plant shoot was inoculated with H. grandella eggs, and the other in which the bud was inoculated with third instars. Damage in each experiment was assessed by the number of frass piles, number and length of tunnels, number of damaged leaves, and damage to the apical bud. Larval performance was evaluated in terms of time to reach pupation and pupal weight and length. In both experiments, plant damage differed significantly among treatments (P < 0.03). Resistant rootstocks conferred resistance to susceptible scions. In both experiments, grafting by itself, regardless of the rootstock and scion combination, also reduced damage caused by H. grandella larvae. Scions of autografted susceptible species had similar resistance to susceptible scions grafted on resistant rootstocks. Few larvae reached pupation, and their pupal weight and length were similar.


Subject(s)
Animals , Lepidoptera/physiology , Meliaceae/parasitology , Meliaceae/physiology
13.
Rev. colomb. biotecnol ; 12(1): 12-21, jul. 2010. graf, tab
Article in Spanish | LILACS | ID: lil-590640

ABSTRACT

La polilla del tomate (Tuta absoluta Meyrick; Lepidoptera: Gelechiidae) es una de las plagas más devastadorasdel tomate en Colombia y países suramericanos, produciendo pérdidas de hasta el 100% en cultivos sin protección.En 2009, T. absoluta se detectó en España, Portugal y países del mediterráneo, además de Inglaterra,Bulgaria y Alemania. Para su control se utilizan insecticidas químicos que generan resistencia e impactoambiental y de salud. La alternativa de utilizar biopesticidas contra esta plaga es de importancia creciente. Eneste estudio se evaluaron cinco métodos de bioensayo para medir adecuadamente la toxicidad sobre larvasde T. absoluta de tres productos comerciales: Dipel®, XenTary® y Turilav®, formulaciones a base de Bacillusthuringiensis (Bt). El método de Inmersión del folíolo, con el producto Dipel®, causó el 100% de mortalidadde larvas y 96% de supervivencia del testigo; este método presentó diferencias significativas al segundo(F=0,025, p>0,05) y cuarto (F=0,0018, p>0,05) día después de la aplicación (DDA). El método de Aspersiónfoliar por aerógrafo produjo 100% de mortalidad de larvas con Dipel® al segundo DDA (F=7,94x10-10,p> 0,05), y produjo diferencias significativas también al cuarto DDA (F=3,45x10-6, p>0,05). Los métodosFoliolos sumergidos y Medio de cultivo provocaron una alta mortalidad en el control por lo que fueron rechazados.El uso de Dipel®, XenTari® y Turilav® en concentración de 1,25 g/L causó entre 80-100% demortalidad entre el segundo y octavo DDA en tres métodos evaluados válidos (1, 2, 3), además corrobora laactividad biológica de B. thuringiensis sobre este insecto plaga.


The tomato moth (Tuta absoluta Meyrick; Lepidoptera: Gelechiidae) is one of the most devastating tomatopests in Colombia and South-American countries, producing losses of up to 100% in unprotected crops. T.absoluta was detected in Spain, Portugal and Mediterranean countries in 2009, as well as England, Bulgaria andGermany. Chemical insecticides are used for controlling it; however, they produce resistance and an environmentaland human health impact. Finding an alternative to using biopesticides against this pest is becomingincreasingly important. This study evaluated five bioassay methods measuring three commercial products’toxicity on T. absoluta larvae: Dipel, XenTary and Turilav Bacillus thuringiensis (Bt) -based formulations. The leafdipping bioassay method caused 100% larvae mortality with Dipel, the control group having 95% survivalrate. The other products showed significant differences on the 2nd (F=0.025, p>0.05) and 4th (F=0.0018,p>0.05) days after application (DAA). The leaf spray airbrush method produced 100% larvae mortality withDipel on the 2nd DAA, having significant differences from the other products tested on 2nd (DAA F=7.94 x10-10, p>0.05 ), 4th (F=3.45x10-6, p>0.05 ) and 8th (F=1.07x10-5, p>0.05 ) DAA. Submerged leaflet and culturemedium methods caused high mortality in controls and were thus rejected. A variation of the leaflet immersionmethod was standardised. The three commercial products produced high mortality in Lab conditionsregarding T. absolute larvae control at 1.25 g/L concentration, thereby corroborating the biological activity ofB. thuringiensis against this insect pest.


Subject(s)
Lepidoptera/physiology , Lepidoptera/genetics , Lepidoptera/microbiology , Lepidoptera/parasitology , Lepidoptera/chemistry , Bacillus thuringiensis/physiology , Bacillus thuringiensis/genetics , Bacillus thuringiensis/immunology , Bacillus thuringiensis/chemistry
14.
Neotrop. entomol ; 39(3): 315-318, May-June 2010. ilus
Article in English | LILACS | ID: lil-556513

ABSTRACT

Reproduction of most insects depend on nutrients accumulated during the larval stage, but many lepidopteran species will also depend on nutrients obtained at the adult stage. Feeding at the adult stage allows the intake of carbohydrate and amino acid rich solutions, which may have an effect on the species reproduction and population growth. The objectives of the current study were to characterize the effects of sugar consumption by adults of the potato tuber moth, Phthorimaea operculella (Zeller), on its reproduction. To initially test the food intake by adults, a 10 percent honey solution or water (control), both containing a liquid dye were offered to adult insects 24h after emergence, and the presence of the dye was observed by analysis of their digestive system. The effects of adult feeding on a 10 percent honey solution on the reproductive performance of P. operculella were evaluated by assessing the oviposition rate, fecundity and fertility. Adult feeding was proved by the presence of the dye within the digestive system of adults of P. operculella. Although the oviposition rate and fertility were not affected by adult feeding, female fecundity was higher in honey-fed females as compared to the water-fed females.


Subject(s)
Animals , Female , Carbohydrates , Eating , Lepidoptera/physiology , Age Factors , Reproduction
15.
Neotrop. entomol ; 39(3): 324-329, May-June 2010. ilus
Article in English | LILACS | ID: lil-556515

ABSTRACT

Crocidosema aporema (Walsingham) is a major pest of legumes in the southern cone of Latin America. The mating behaviour of two allopatric populations (Uruguay and Brazil) of C. aporema kept in captivity was studied by observing the posture of calling females, the temporal pattern of pheromone emission and mating, and the response of males to calling females in olfactometer tests. Female calling and mating was observed during the scotophase, from the first to the seventh night after adult emergence. Male response was evaluated at night using a single calling female in a Y-shaped olfactometer. Females adopted a characteristic calling posture, extruding the pheromone gland from the tip of the abdomen. Most females started calling during the second scotophase, and all females called from the third, between the fifth and seventh hours after the onset of the scotophase. Most of the couples mated once throughout the experiment, between the third and sixth night and during the middle of the dark phase. Males preferentially chose the female arm in olfactometer tests, considering both the first arm chosen and the number of visits during the observation period. Our results describe for the fi rst time the temporal pattern associated to the reproductive behaviour of C. aporema. We also provide evidence that this tortricid is monoandrous, and that pheromones are used in intersexual communication for mate finding. Our data will be used to optimize the collection of female sex pheromones for chemical characterization in order to develop a monitoring tool for this pest.


Subject(s)
Animals , Female , Male , Lepidoptera/physiology , Sexual Behavior, Animal , Time Factors
16.
Neotrop. entomol ; 39(3): 330-337, May-June 2010. ilus, tab
Article in Portuguese | LILACS | ID: lil-556516

ABSTRACT

The oriental fruit moth, Grapholita molesta (Busck), stands out as one of the most important pest in Rosaceae orchards in Brazil. During feeding, caterpillars bore into shoots, branches and fruits, impairing the commercial production. This work aimed to study the effect of endogenous factors in the chemical perception and in the species chemotactic behavior, seeking to optimize monitoring and the behavioral control of this pest. We evaluated male electroantennographical (EAG) and chemotactical (olfactometry) responses to the synthetic sex pheromone in different ages, virgins or mated and fed or unfed. The EAG responses of males did not differ for all evaluated factors. Nevertheless, the chemotactical behavior of males seems to decrease with age, not varying as a function of mating or feeding conditions. The knowledge about the interference of these factors in G. molesta may help with the interpretation of field results, allowing the development of suitable and reliable control measures based on infochemicals for behavioral control.


Subject(s)
Animals , Male , Lepidoptera/physiology , Sex Attractants/physiology , Age Factors , Copulation , Eating
17.
Neotrop. entomol ; 39(3): 420-423, May-June 2010. ilus
Article in English | LILACS | ID: lil-556528

ABSTRACT

Spodoptera frugiperda (J E Smith) is an important pest of several crops, but especially on maize in Brazil. The implementation of biological control measures hinges on the identification of its predators and other natural enemies. As a means of identifying predators, antibodies against S. frugiperda eggs were generated by inoculating rabbits with macerated S. frugiperda eggs, and the production of antibodies against S. frugiperda egg proteins was verifi ed by double immunodiffusion (DID). These antibodies were then utilized in another serological technique, counterimmunoeletrophoresis (CIE), to identify insects that could have ingested S. frugiperda eggs. Macerates of entire insects collected in maize plantations and of individual parts of their digestive tract, including the crop, were the source of antigens in the CIE, while predators fed S. frugiperda eggs in the laboratory served as the control. Antibodies produced by the inoculated rabbits were effective in detecting S. frugiperda egg proteins, especially if crop macerates were used as antigens. Among the species of insects collected from maize plantations, Lagria villosa Fabricius (Coleoptera: Lagriidae) and a species of Lygaeidae (Hemiptera) were identified as possible S. frugiperda predators.


Subject(s)
Animals , Rabbits , Lepidoptera/physiology , Spodoptera/parasitology , Antibodies/blood , Lepidoptera/immunology , Serologic Tests
18.
Neotrop. entomol ; 39(2): 172-180, mar.-abr. 2010. ilus, tab, graf
Article in Portuguese | LILACS | ID: lil-547677

ABSTRACT

This research evaluates the effect of the adult diet on the reproduction of Anticarsia gemmatalis Hübner, Heliothis virescens (Fabr.), Spodoptera frugiperda (J. E. Smith) (Noctuidae), Diatraea saccharalis (Fabr.) (Crambidae), Gymnandrosoma aurantianum Lima (Tortricidae) and Stenoma catenifer Walsingham (Elachistidae). Adults of all species were fed either water or a 10 percent honey solution. The egg viability for the 1st and 2nd egg masses, adult fecundity, longevity, number of mating and the ovigeny index (OI) (degree of ovarian maturation) were evaluated. Fecundity of A. gemmatalis and H. virescens was drastically reduced when females were fed only on water. Egg viability from both 1st and 2nd egg masses was variable between treatments. Females of A. gemmatalis, H. virescens and S. frugiperda, and males of some species had a reduced longevity when fed only on water. The number of matings was higher for A. gemmatalis and D. saccharalis when fed on water only. The OI was < 1.0 for all species evaluated indicating that all females may develop new oocytes as they age. Based on the OI and the reduced fecundity of A. gemmatalis and H. virescens, one observes that adult feeding is important for the reproduction of both species, and the IO is not a good parameter to indicate such condition. Spodoptera frugiperda, G. aurantianum, D. saccharalis and S. catenifer do not require any source of carbohydrates as adults to sustain their reproduction.


Subject(s)
Animals , Female , Male , Diet , Lepidoptera/physiology , Longevity , Reproduction
19.
Neotrop. entomol ; 39(2): 181-186, mar.-abr. 2010. graf, tab
Article in Portuguese | LILACS | ID: lil-547678

ABSTRACT

Among the important pests of coconut, the coconut moth Atheloca subrufella (Hulst) is a significant pest of flowers and fruits, and is found across all coconut-producing regions in Brazil. We investigated the thermal requirements of A. subrufella and estimated the number of generations for two different growing coconut regions in Pernambuco State. The developmental time of all immature stages reduced as the temperature increased. The egg to adult period ranged from 19.3 to 59.8 days from 32ºC to 18ºC, respectively. The survival of the period from egg to adult was 25 percent at extreme temperatures (18ºC and 32ºC), while at the intermediate temperatures it was over 72 percent. Based on the thermal requirements determined for A. subrufella and the average temperatures determined for "Zona da Mata" and "Sertão" of Pernambuco State, it was estimated that A. subrufella is able to complete up to 13 generations per year in both areas. These results indicate that A. subrufella exhibited development and reproduction limited by temperatures higher than 32ºC and lower than 18ºC. However, based on the thermal requirements of A. subrufella and the mean temperatures of the "Zona da Mata" and "Sertão" of Pernambuco State, this pest can develop throughout the entire year.


Subject(s)
Animals , Cocos/parasitology , Lepidoptera/physiology , Temperature
20.
Braz. j. biol ; 70(1): 103-109, Feb. 2010. ilus, tab
Article in English | LILACS | ID: lil-539738

ABSTRACT

Folivore cerrado caterpillars are found on their host species in low frequencies, which vary between plants and throughout the year. We analysed the effects of climatic variation and of the characteristics of two host species (Miconia, Melastomataceae) on caterpillar abundance. The work was carried out in a cerrado sensu stricto area in Brasília, Federal District, Brazil, from May 1998 to September 1999. One hundred plants of each species were inspected monthly. All caterpillars found were collected and raised in the laboratory with Miconia leaves as food sources. Climatic data for the study area and plant characteristics such as local density, spatial distribution, foliar phenology, leaf pilosity and nutritional content were used to test the effects on caterpillar abundance. Less than 10 percent of the plants had larvae. Caterpillars were more frequent and abundant in M. pohliana, which was also present at higher densities than M. ferruginata. Low caterpillar frequency in host plants and an abundance peak during the dry season are consistent patterns for different cerrado Lepidoptera larvae. This abundance peak, however, is not coincident with higher leaf production in host species. We suggest that M. pohliana's higher local density and better leaf digestibility can account for the higher abundance of caterpillars in this species.


No cerrado, as lagartas de Lepidoptera, folívoras externas, são encontradas em baixas frequências e variam entre plantas e ao longo do ano. Este trabalho teve como objetivo analisar os efeitos das variações climáticas e das características das plantas (Miconia, Melastomataceae) na abundância das lagartas. O estudo foi feito no cerrado sensu stricto, Brasília, DF, de maio de 1998 a setembro de 1999. Mensalmente, 100 plantas de cada espécie foram vistoriadas. Todas as lagartas foram coletadas e criadas. Foram correlacionados com os resultados obtidos da abundância de lagartas, os dados climáticos e as seguintes características das plantas: densidade local, distribuição espacial, fenologia, pilosidade e conteúdo nutricional foliar. Menos de 10 por cento das plantas tinham lagartas. As lagartas foram mais frequentes e abundantes em M. pohliana que também foi a espécie de planta com maior densidade na área. A frequência baixa de lagartas em plantas do cerrado é um padrão bastante consistente, assim como o pico de abundância desses imaturos na estação seca. Entretanto, esse pico de abundância não coincide com a produção de folhas em nenhuma das espécies de plantas. A maior densidade local e digestibilidade das folhas de M. pohliana são os fatores que mais explicam a abundância de lagartas nessa espécie.


Subject(s)
Animals , Feeding Behavior/physiology , Lepidoptera/physiology , Melastomataceae/parasitology , Host-Parasite Interactions/physiology , Population Density , Plant Leaves/parasitology , Seasons
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