RESUMEN
Injury by herbivores is a major biotic stress that limits soybean [Glycine max (L.) Merrill] crop production. Among the main soybean insect pests, Anticarsia gemmatalis Hübner is responsible for causing significant economic damage in soybean. The primary management strategy for this insect is chemical control and use of Bt transgenic soybean. Alternative strategies, such as host plant resistance, are considered an efficient and less-aggressive method, especially in association with other strategies as part of an integrated pest management (IPM) approach. In this study, we evaluated 30 soybean genotypes to verify antixenosis expression through oviposition, attractiveness, and food consumption tests. From this, we selected 13 promising genotypes to verify the possible presence of antibiosis. Our results suggest that antixenosis was found in genotypes 'TMG 133' RR, 'TMG 1179' RR, 'IAC 19', 'IAC 17', 'IAC 100', D75-10169, and IAC 78-2318. By influence on behavior and negative impact on larval viability, antixenosis and antibiosis were indicated for the genotypes IAC 74-2832, 'IAC 19', 'IAC 17', 'IAC 100', and PI 274454. 'TMG 7062' IPRO was found to provide antibiosis resistance by negatively affecting larval development and viability. Because of reduced food consumption by larvae, antixenosis was indicated for 'IAC 24'. These genotypes should be considered in soybean breeding programs focusing on soybean resistance to A. gemmatalis.
Asunto(s)
Lepidópteros , Mariposas Nocturnas , Animales , Antibiosis , Genotipo , Larva , Mariposas Nocturnas/genética , Glycine max/genéticaRESUMEN
Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East Asia Minor 1 is one of the most important pests of the common bean, due to its potential of causing direct and indirect damage. This study aimed to evaluate 78 bean genotypes to verify the occurrence of resistance of antixenosis type against B. tabaci. Initially, multiple-choice trials were performed to evaluate the oviposition preference and nymphs' establishment at 3 and 15 days after infestation. Subsequently, 21 bean genotypes were selected, and a no-choice test was conducted. Colorimetric analyses were performed to establish correlations between leaf color and insect establishment. In multiple-choice trial, the genotypes BRS Ametista, BRS Estilo, BRS Esplendor, SCS 204 Predileto, BRS Notável, IPR Eldorado, CHIB 06, IPR Quero-Quero, Iapar 81, CHIP 338, IPR Garça, Arcelina 4, SCS 202 Guará, IAC Esperança, H96102-1-1-1-52, CHIP 348, Carioca Comum, CHIP 300, IAC Carioca Eté, IAC Ybaté, and Tybatã were the least used for oviposition and nymph establishment, demonstrating antixenosis or antibiosis. In the no-choice trial, most genotypes were less attractive to whitefly, and the genotypes CHIB 06, IPR Garça, CHIP 300, and IAC Esperança had less oviposition. The most attractive genotypes presented high luminosity and more intense green and yellow colors, indicating positive correlation. Therefore, the genotypes BRS Ametista, SCS 204 Predileto, BRS Estilo, IPR Eldorado, SCS-202 Guará, Carioca Comum, Arcelina 4, CHIP 348, and IAC Esperança showed the highest resistance stability in the no-choice trial, and they are promising sources of antixenotic factors for use in breeding programs to obtain whitefly-resistant common bean lines.
Asunto(s)
Hemípteros , Herbivoria , Phaseolus/genética , Animales , Brasil , Color , Femenino , Genotipo , Ninfa , Oviposición , Hojas de la Planta , TricomasRESUMEN
Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is an important pest capable of colonizing several species of cultivated plants, including soybean [Glycine max (L.) Merrill]. The primary management strategy for this insect is chemical control and adoption of Bt plants. However, alternative environmentally friendly strategies should be investigated and adopted as available for sustainable management of this insect pest. One potential underutilized method for insect control is plant resistance. The objective of this study was to categorize resistance (antixenosis and antibiosis) of 22 soybean genotypes on H. armigera in a laboratory setting. A preliminary experiment was conducted using soybean leaves and pods to determine the most promising genotypes for resistance. For each selected genotype, we collected biological parameters, leaf intake, and performed confinement tests. The genotypes PI 227687, PI 274453, PI 274454, PI 229358, PI 171451, 'IAC 17', and 'IAC 19' expressed resistance against H. armigera. Each genotype lowered larval survivorship. The genotypes PI 229358, PI 227687, PI 274453, and PI 274454 expressed resistance by prolonging larval development and reducing fifth-instar larvae weight. 'IAC 19' reduced leaf consumption and lowered the weight of fifth-instar larvae. Antixenosis was found in genotypes PI 227687, PI 274454, and 'IAC 19'. These genotypes might be used in breeding programs focusing on soybean resistance to lepidopterans.
Asunto(s)
Lepidópteros , Mariposas Nocturnas , Animales , Genotipo , Control de Insectos , Larva , Glycine maxRESUMEN
Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) is an important pest of vegetable crops, including collard greens Brassica oleracea var. acephala (Brassicaceae). The use of resistant genotypes is an interesting option to reduce insect populations and can be used as an important tool for integrated pest management (IPM). This study evaluated 32 genotypes of collard greens against the attack of silver leaf whitefly, with the aim to characterize antixenosis. Initially, a multiple-choice trial was conducted using all genotypes, in which the adult attractiveness was assessed on two leaves per genotype at 24 and 48 h after infestation. After 48 h, one leaf of each genotype was randomly selected for the determination of the number of eggs per square centimeter. From the results of the multiple-choice trial, 13 genotypes were selected for a no-choice oviposition test, following the same method of the previous test. Colorimetric analyses were also performed to establish possible correlations between leaf color and insect colonization. Genotypes HS-20, OE, and VA were less attractive, demonstrating antixenosis. Genotypes LG, VE, J, MG, MOP, HS-20, VA, and MT had less oviposition in the multiple-choice test, which indicated expression of antixenosis. In the no-choice test, genotypes VE, P1C, CCB, RI-919, H, and J had less oviposition, which also characterized antixenosis. Therefore, genotypes VE and J showed the highest resistance stability because both had less oviposition in both test modalities. Thus, the resistance to B. tabaci biotype B indicates the genotypes HS-20, OE, VA, VE, and J are promising for use in breeding programs to develop resistance to whitefly.
Asunto(s)
Brassica/genética , Hemípteros/fisiología , Herbivoria , Animales , Colorimetría , Femenino , Genotipo , Oviposición , Control de Plagas , Pigmentación , Hojas de la PlantaRESUMEN
This study aimed to evaluate the biotic potential and life table of individuals of Helicoverpa armigera (Hübner) from different host plants (citrus, corn, and cotton) and Brazilian states (São Paulo, Distrito Federal, and Bahia) in artificial diet, under laboratory conditions (25 ± 1°C, 70 ± 10% RH, 14 h photophase). The longevity, pre-, post- and oviposition periods, fecundity, and fertility of 15 mating pairs per origin were evaluated. We also compared the reproductive parameters of each group of insects (São Paulo (SP), Distrito Federal (DF), and Bahia (BA)), including the net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (r m), and finite rate of increase (λ). Microsatellite analysis from individuals collected in different locations and host plants did not show differences among the parental insects. It was verified that parental progeny collected in cotton fields from Bahia had a higher biotic potential, a higher reproductive rate (Ro), and a better fecundity compared to the insects from remaining regions. The life table charts indicate that the highest values for the reproductive parameters of the Bahia progeny are associated with higher specific fertility, particularly in early adulthood. The greatest biotic potential of the Bahia progeny may be due to increased selection pressure from the insecticide used (organophosphate and pyrethroid) on cotton crops compared to that of other crops, as well due to the massive adoption of Bt cotton-producing areas of that state from 2013 outbreaks.
Asunto(s)
Lepidópteros/fisiología , Animales , Brasil , Citrus , Dieta , Femenino , Fertilidad , Gossypium , Tablas de Vida , Longevidad , Masculino , Repeticiones de Microsatélite , Oviposición , Reproducción , Zea maysRESUMEN
Bemisia tabaci biotype B (Gennadius) is one of the most important soybean pest worldwide. Herein, 15 soybean genotypes were evaluated, to characterize the occurrence of antixenosis to B. tabaci biotype B. Initially, a multiple-choice test with all genotypes was carried out, evaluating the settling and oviposition preference at 3 d after infestation, and the colonization by nymphs after 48 d of infestation. Subsequently, a no-choice test, using 14 genotypes, was conducted with infested plants individually, and the number of eggs was counted after 72 h. Then, 10 genotypes were selected (indicative of resistance and susceptibility), which were evaluated for whitefly settling 24, 48, and 72 h after infestation and for oviposition 72 h after infestation. The trichomes of the leaflets were characterized for density, size, and inclination to establish possible correlations with the settling and oviposition in the genotypes. In the first multiple-choice test, involving 15 genotypes, 'IAC-17,' 'IAC-19,' and UX-2569-159 expressed antixenosis against B. tabaci. 'Jackson,' 'P98Y11,' and PI-229358 exhibited the same behavior in the no-choice test. In the multiple-choice test, 'Jackson,' 'P98Y11,' and 'TMG1176 RR' were the least attractive and least used for oviposition. The antixenosis shown by 'Jackson,' 'P98Y11,' and PI-229358 may be related to the characteristics of the trichomes (lower density and inclined). Based on the experiments carried out, 'IAC-17,' 'IAC-19,' 'Jackson,' 'P98Y11,' PI-229358, TMG1176 RR, and UX-2569-159 are considered promising for resistance to B. tabaci biotype B and may be exploited in soybean breeding programs for resistance to insects.
Asunto(s)
Antibiosis , Genotipo , Glycine max/fisiología , Hemípteros/fisiología , Herbivoria , Animales , Conducta de Elección , Cadena Alimentaria , Hemípteros/genética , Hemípteros/crecimiento & desarrollo , Ninfa/genética , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Hojas de la Planta/fisiología , Glycine max/genéticaRESUMEN
The soybean looper Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae) is known as an important pest of leguminous plants worldwide. In Brazil, this pest species is gaining importance to producers of the common bean Phaseolus vulgaris L. (Fabaceae) because it limits field production of the crop. Chemical control is still the primary method of insect control. However, due to the possible harmful effects of pesticides to humans and the environment, alternative and less aggressive practices are being investigated. For this reason, the use of resistant plant genotypes represents a valuable tool in insect control. This study evaluated the biological aspects of larvae of C. includens confined to 14 bean genotypes under laboratory conditions (26 ± 2°C; 65 ± 10% RH; photoperiod of 14 h L:10 h D). The duration of the instars, total duration of the larval phase, consumption while in the larval phase, weight of the fifth instar larvae, larval viability, duration of the pre-pupal and pupal phases, pupal weight, pupal viability, pupal deformity, caterpillar-to-adult cycle, duration of the pre-oviposition and oviposition periods, and total number of viable eggs per female were evaluated. The genotypes "IAC Boreal," "IAC Harmonia," and "IAC Formoso" expressed antibiosis, prolonging the caterpillar-to-adult cycle and reducing the larval viability; however, each of these genotypes also experienced high leaf consumption. "IAC Jabola" expressed moderate levels of antibiosis and/or antixenosis (feeding), while the genotype "BRS Horizonte" expressed antixenosis (feeding). The data obtained with IAC Boreal, IAC Harmonia, IAC Formoso, IAC Jabola, and BRS Horizonte are promising and may help with the improvement of programs aimed at managing C. includens damage to this leguminous agricultural crop.
Asunto(s)
Herbivoria , Mariposas Nocturnas/crecimiento & desarrollo , Phaseolus/genética , Animales , Brasil , Productos Agrícolas , Genotipo , Larva/crecimiento & desarrollo , Control Biológico de Vectores , Pupa/crecimiento & desarrolloRESUMEN
Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) has been recognized as an important pest of many agricultural systems including soybean [Glycine max (L.) Merrill] crops. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM). This study aimed to evaluate the biological development of Bemisia tabaci biotype B confined on 13 soybean genotypes under greenhouse conditions. Initially, the nymphal period, complete development period (egg-adult), and the viability of the silverleaf whitefly nymphs were evaluated in all genotypes. Then, four genotypes promising for resistance ('Jackson,' UX-2569-159, 'P98Y11,' and 'TMG132 RR') and a susceptible genotype (PI-227687) were selected for further assays, where two insect populations were compared: a first population from the initial rearing (cabbage plants) and another corresponding to insects previously reared out on the selected genotypes. In addition to the parameters evaluated in preliminary tests, we also determined the viability and incubation period of eggs. Moderate levels of resistance (antibiosis/antixenosis) to B. tabaci biotype B were found in three genotypes. 'P98Y11' and 'TMG132 RR' were less suitable for insect development, extending the development cycle, and UX-2569-159 caused high nymphal mortality. We did not observe a significant increase in the level of plant resistance by the use of previously stressed insects. This suggests that the evaluation of a single whitefly generation may be sufficient to make correct decisions on promising soybean genotypes.
Asunto(s)
Genotipo , Glycine max/genética , Hemípteros , Control de Plagas , Animales , NinfaRESUMEN
The western bean cutworm Striacosta albicosta (Smith), the fall armyworm Spodoptera frugiperda (J. E. Smith), and the corn earworm Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) are among the major lepidopteran pests of maize in the United States, belonging to the same guild and injuring the reproductive tissues of this crop. Here, intraguild competition of these lepidopterans on non-Bt maize was evaluated through survival analysis of each species under laboratory and field conditions. Competition scenarios were carried out in arenas containing maize silk or ear tissue, using larvae on different stadium of development. Fitness cost competition studies were conducted to examine the influence of intraguild competition and cannibalism and predation rates on larval development. The survival of S. albicosta competing with the other species was significantly lower than in intraspecific competition, even when the larvae were more developed than the competitor. For S. frugiperda, survival remained high in the different competition scenarios, except when competing in a smaller stadium with H. zea Larvae of H. zea had a high rate of cannibalism, higher survival when competing against S. albicosta than S. frugiperda, and reduced survival when the H. zea larvae were at the same development stadium or smaller than the competitors. Based on fitness cost results, the absence of a competitor for the feeding source may confer an advantage to the larval development of S. frugiperda and H. zea Our data suggest that S. frugiperda has a competitive advantage against the other species, while S. albicosta has the disadvantage in the intraguild competition on non-Bt maize.
Asunto(s)
Cadena Alimentaria , Mariposas Nocturnas/fisiología , Zea mays , Animales , Conducta Competitiva , Conducta Alimentaria , Aptitud Genética , Larva/genética , Larva/crecimiento & desarrollo , Larva/fisiología , Mariposas Nocturnas/genética , Mariposas Nocturnas/crecimiento & desarrollo , Zea mays/crecimiento & desarrolloRESUMEN
Integrated pest management (IPM) and insect resistance management (IRM) in various cropping systems demand a comprehensive understanding of insect behavior. Among the needed information is basic charaterizations of larval movement and dispersion of some insect-pests, such as the noctuids Striacosta albicosta (Smith) and Spodoptera frugiperda (J.E. Smith). We investigated the plant-to-plant movement of western bean cutworm and fall armyworm larvae in field of maize. Experiments on S. albicosta were conducted between 2008 and 2010. A main study with this pest was performed in 2012 in a randomized complete block design (RCBD) with nine replications. An S. frugiperda study was performed in 2013 in an RCBD with eight replications. The plant-to-plant movement and larval survival were measured in plots with maize nontoxic to the insects. The larval survival of S. albicosta presented high variety throughout the years. Although S. frugiperda survival was relatively low during 2013, it did not compromise the larval assessment. Larvae of both species dispersed governed by nondirectional sensory information, and presented aggregated and symmetrical distribution; however, fall armyworm remained nearer the release point. These results may help the IPM components, such as scouting and economic threshold, as well as the implementation of refuge and seed mixture strategies for IRM.
RESUMEN
The silverleaf whitefly Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) is one of the most severe tomato pests in the world. The damage caused by this insect may compromise up to 100% of crop production, and management of this pest has relied on spraying of synthetic insecticides. However, due to the environmental issues associated with this practice, alternative methods such as the use of botanical pesticides are now used as a strategy of integrated pest management (IPM). We evaluated the effects of essential oils of five plant species on B. tabaci biotype B in tomato and demonstrate that the essential oils (0.5%) of Piper callosum (PC-EO), Adenocalymma alliaceum (AA-EO), Pelargonium graveolens (PG-EO), and Plectranthus neochilus (PN-EO) inhibit the settlement and oviposition of B. tabaci biotype B adults in tomato plants. In fumigation tests, A. alliaceum (AA-EO) at 0.4 µL/L of air after 72 h and 0.1 µL/L of air after 6 h was the most effective against nymphs and adults of B. tabaci biotype B, respectively. The major chemical constituents of PC-EO were identified as being safrole (29.3%), α-pinene (19.2%), and ß-pinene (14.3%), whereas diallyl trisulfide (66.9%) and diallyl disulfide (23.3%) were the major compounds identified in AA-EO. This is the first report on the reduction of oviposition by the use of P. callosum (PC-EO) and A. alliaceum (AA-EO). In addition, the fumigant effect of A. alliaceum (AA-EO) on nymphs and adults has also been reported here for the first time.
Asunto(s)
Hemípteros/efectos de los fármacos , Insecticidas , Aceites Volátiles/farmacología , Control Biológico de Vectores , Aceites de Plantas/farmacología , Solanum lycopersicum , Animales , Femenino , NinfaRESUMEN
Pentatomids (stink bugs) are major pests of soybean, Glycine max (L.) Merril. These pests reach high levels of infestation, cause severe damage to seeds by feeding, are linked to leaf retention, and are difficult to control. Host plant resistance is considered to be a valuable tool in integrated pest management and can assist in reducing the damage caused by stink bugs. This research evaluated the resistance of soybean genotypes in Brazil to the stink bug complex, the Neotropical brown stink bug, Euschistus heros (F.), redbanded stink bug, Piezodorus guildinii (Westwood), southern green stink bug, Nezara viridula (L.), green belly stink bug, Dichelops melacanthus (Dallas), and Edessa meditabunda (F.), by assessing infestation assay, yield reduction, seed damage, and leaf retention. Certain genotypes expressed different categories of resistance: least infested, low yield reduction, low levels of damage in seeds, and low levels of leaf retention. PI lines and IAC 78-2318 showed antixenotic resistance, and 'IAC 100' showed tolerance for the stink bug complex. This is the first study to evaluate several parameters of yield and seed quality using different soybean maturity groups under relatively high infestation by the three stink bugs species. The promising genotypes might be used in regions with a high incidence of stink bugs to manage their populations in combination with other integrated pest management practices.
Asunto(s)
Glycine max/genética , Herbivoria , Heterópteros , Animales , GenotipoRESUMEN
Spodoptera frugiperda J.E. Smith (fall armyworm) is considered one of the most destructive pests of corn throughout the Americas. Although this pest has been extensively studied, little is known about its larval movement and feeding behavior on reproductive compared to vegetative corn stages. Thus, we conducted studies with two corn stages (R1 and R3) and four corn plant zones (tassel, above ear, ear zone, and below ear) in the field at Concord, NE (USA), and in the field and greenhouse at Botucatu, SP (Brazil), to investigate on-plant larval movement. The effects of different corn tissues (opened tassel, closed tassel, silk, kernel, and leaf), two feeding sequence scenarios (closed tassel-leaf-silk-kernel and leaf-silk-kernel), and artificial diet (positive control) on larval survival and development were also evaluated in the laboratory. Ear zone has a strong effect on feeding choice and survival of fall armyworm larvae regardless of reproductive corn stage. Feeding site choice is made by first-instar. Corn leaves of reproductive plants were not suitable for early instar development, but silk and kernel tissues had a positive effect on survival and development of fall armyworm larvae on reproductive stage corn.
Asunto(s)
Spodoptera/fisiología , Zea mays , Animales , Brasil , Conducta Alimentaria , Larva/crecimiento & desarrollo , Larva/fisiología , Movimiento , Nebraska , Spodoptera/crecimiento & desarrollo , Zea mays/crecimiento & desarrolloRESUMEN
Changes in protein content, peroxidase activity, and isozyme profiles in response to soybean aphid feeding were documented at V1 (fully developed leaves at unifoliate node, first trifoliate leaf unrolled) and V3 (fully developed leaf at second trifoliate node, third trifoliate leaf unrolled) stages of soybean aphid-tolerant (KS4202) and -susceptible (SD76R) soybeans. Protein content was similar between infested and control V1 and V3 stage plants for both KS4202 and SD76R at 6, 16, and 22 d after aphid introduction. Enzyme kinetics studies documented that control and aphid-infested KS4202 V1 stage and SD76R V1 and V3 stages had similar levels of peroxidase activity at the three time points evaluated. In contrast, KS4202 aphid-infested plants at the V3 stage had significantly higher peroxidase activity levels than control plants at 6 and 22 d after aphid introduction. The differences in peroxidase activity observed between infested and control V3 stage KS4202 plants at these two time points suggest that peroxidases may be playing multiple roles in the tolerant plant. Native gels stained for peroxidase were able to detect differences in the isozyme profiles of aphid-infested and control plants for both KS4202 and SD76R.
Asunto(s)
Antibiosis , Áfidos/fisiología , Glycine max/genética , Herbivoria , Peroxidasas/genética , Proteínas de Plantas/genética , Animales , Femenino , Peroxidasas/metabolismo , Proteínas de Plantas/metabolismo , Glycine max/metabolismoRESUMEN
The soybean aphid, Aphis glycines Matsumura, has become the most significant soybean [Glycine max (L.) Merrill] insect pest in the north central soybean production region of North America. The objectives of this research were to measure selected genotypes for resistance to the soybean aphid in the later vegetative and reproductive stages under field conditions, and confirm the presence of tolerance in KS4202. The results from 2007 to 2011 indicate that KS4202 can support aphid populations with minimal yield loss at levels where significant yield loss would be expected in most other genotypes. The common Nebraska cultivar, 'Asgrow 2703', appears to show signs of tolerance as well. None of the yield parameters were significantly different between the aphid infested and noninfested treatments. Based on our results, genotypes may compensate for aphid feeding in different ways. Asgrow 2703 appears to produce a similar number of seeds as its noninfested counterpart, although the seeds produced are slightly smaller. Field evaluation of tolerance in KS4202 indicated a yield loss of only 13% at 34,585-53,508 cumulative aphid-days, when 24-36% yield loss would have been expected.
Asunto(s)
Antibiosis , Áfidos/fisiología , Glycine max/genética , Animales , Conducta Alimentaria , Nebraska , Ninfa/crecimiento & desarrollo , Control Biológico de Vectores , Densidad de Población , Estaciones del Año , Glycine max/fisiologíaRESUMEN
Bemisia tabaci biótipo B é um dos principais insetos-praga na cultura da abobrinha (Cucurbita pepo L.). O manejo dessa mosca-branca tornou-se grande desafio aos agricultores, uma vez que esta apresenta rápida capacidade de desenvolver resistência a diferentes classes de inseticidas. Como alternativa vem sendo investigado o uso de extratos vegetais com atividades inseticida e/ou insetistática, os quais têm revelado resultados promissores no combate a inseto. O presente trabalho teve por objetivo avaliar os possíveis efeitos de sete extratos provenientes de cinco espécies vegetais, Ruta graveolens L. (folhas), Azadirachta indica A. Juss. (folhas + ramos), Trichilia pallida Swartz (ramos), T. pallida (folhas), A. indica (amêndoas), Chenopodium ambrosioides L. (inflorescências + ramos+ folhas) e Mentha pulegium L. (folhas), sobre Bemisia tabaci biótipo B em abobrinha, por meio de testes de repelência e deterrência para oviposição. Em teste com chance de escolha, avaliou-se a atratividade e determinou-se o índice de repelência após 6, 24 e 48 horas da aplicação dos extratos. A oviposição foi verificada após a terceira contagem do número de adultos. O extrato à base de folhas de M. pulegium mostrou repelência e deterrência à oviposição de B. tabaci biótipo B, podendo ser recomendado como alternativa para o manejo do inseto.
Bemisia tabaci biotype B is one of the main pests in squash (Cucurbita pepo L.). The management of this whitefly has become a major challenge to growers, since they have the ability to quickly develop resistance to different classes of insecticides. Alternatively, the use of plant extracts with insecticide and/or insectistatic activities has been investigated, showing promising results for the whitefly control. The present study evaluated the possible effects of seven extracts from five plant species, Ruta graveolens L. (leaves), Azadirachta indica A. Juss. (leaves + branches), Trichilia pallida Swartz (branches), T. pallida (leaves), A. indica (almonds), Chenopodium ambrosioides L. (inflorescence + leaves + branches) and Mentha pulegium L. (leaves) on Bemisia tabaci biotype B in squash, by assays of repellence and oviposition deterrence. In free choice tests, the attractiveness and determination of the rate of repellence (with 6, 24 and 48 hours after application of the extracts) were evaluated. The oviposition was observed after the third counting of the number of adults. The extract of leaves of M. pulegium showed repellence and oviposition deterrence to B. tabaci biotype B and may be recommended as an alternative in the insect management.