Abstract: Andricus quercuslaurinus Melika & Pujade-Villar (Hymenoptera: Cynipidae) is a gall wasp from the branches (asexual reproduction) and leaves (sexual reproduction) of the Quercus affinis Scheidw. oak in Acaxochitlán, Hidalgo, Mexico. Severe infestations on the leaves cause a delay in growth and, given time, the death of trees with large levels of damage. This study evaluated the effectiveness of the pesticides Imidacloprid, Spirotetramat, Acephate and Abamectin when applied through foliar spray on the adult population of wasps that oviposit on the leaves, as well as on the eggs and larvae of the oak galls. Acephate prevented oviposition on the treated foliage. The least number of oak galls was found on the trees treated with Acephate; furthermore, they had no larvae. On the other hand, Spirotetramat had not been evaluated for the control of Cynipidae; alongside Imidacloprid, these pesticides were effective in reducing the survival of eggs and larvae. Spraying the pesticides Acephate (1.20 kg·ha-1), Spirotetramat (0.75 L·ha-1), and Imidacloprid (1.00 L·ha-1) on Q. affinis foliage are options to be considered for the control of A. quercuslaurinus given their significant effects (P = 0.05) on the mortality of the eggs with regard to the control.

Resumen: Andricus quercuslaurinus Melika y Pujade-Villar (Hymenoptera: Cynipidae) es una avispa agalladora de ramas (generación asexual) y hojas (generación sexual) del encino Quercus affinis Scheidw. en Acaxochitlán, Hidalgo, México. Las infestaciones severas en ramas causan retraso del crecimiento y, eventualmente, la mortalidad de árboles que tienen niveles altos de daño. En este trabajo se evaluó la efectividad de los insecticidas Imidacloprid, Espirotetramat, Acefato y Abamectina aplicados mediante aspersión foliar sobre la población de avispas adultas que ovipositan en las hojas, así como sobre los huevos y larvas en las agallas. El Acefato evitó la oviposición sobre el follaje tratado. El menor número de agallas se encontró en los árboles tratados con Acefato; además, no tuvieron larvas. Por otra parte, el Espirotetramat no había sido evaluado para el control de cinípidos y junto con el Imidacloprid fueron efectivos para reducir la supervivencia de huevos y larvas. La aspersión de los insecticidas Acefato (1.20 kg·ha-1), Espirotetramat (0.75 L·ha-1) e Imidacloprid (1.00 L·ha-1) al follaje de Q. affinis son opciones a considerar para el control de A. quercuslaurinus, debido a los efectos significativos (P = 0.05) en la mortalidad de huevos con respecto al testigo.

In the State of Mexico, cut rose (Rosa x hybrida) grown under greenhouse conditions has as a commercial constraint the low phytosanitary quality of its flower buds. To improve this quality, three growth regulators containing cytokinins (two commercial products and one prepared at a dose of 0.001 ppm from a technical-grade growth regulator, all at three frequencies of application) and CP* Floral Protector (FP) were evaluated in cut Rosa x hybrid 'Polo' grown under greenhouse conditions in Villa Guerrero, State of Mexico. A completely randomized experimental design with 20 treatments and four replications in a factorial arrangement was used. Treatments were applied to flower buds of 0.5 cm in diameter with closed sepals. Evaluations were made according to commercial harvest criteria when the petals begin to separate from the center of the flower. The FP and application of growth regulators increased bud diameter and length (P ≤ 0.05), but there was no effect on peduncle length or the number of days to harvest. FP use prevented insect damage and increased the number of export-quality buds. CP® floral protector and growth regulators improve the quality of cut roses.

En el Estado de México, la rosa de corte (Rosa x hybrida) que se produce en invernadero tiene como limitante comercial la baja calidad fitosanitaria de los botones florales. Para incrementar dicha calidad, se evaluaron en Villa Guerrero, Estado de México tres reguladores del crecimiento que contienen citocininas (dos comerciales y uno preparado a la dosis de 0.001 ppm a partir del regulador de crecimiento grado técnico; todas con tres frecuencias de aplicación) y el Protector Floral CP* (PF) en Rosa x hybrida 'Polo' de corte en invernadero. Se utilizó un diseño experimental completamente al azar con 20 tratamientos y cuatro repeticiones en arreglo factorial. Los tratamientos se aplicaron a botones florales de 0.5 cm de diámetro con los sépalos cerrados. Las evaluaciones se hicieron de acuerdo al criterio comercial de punto de corte cuando los pétalos empezaban a separarse del centro de la flor. El PF y la aplicación de reguladores del crecimiento incrementaron el diámetro y longitud del botón (P ≤ 0.05), pero no hubo efecto en la longitud del pedúnculo ni en los días al corte. El uso del PF previno daños por insectos e incrementó el número de botones con calidad de exportación. El protector floral CP* y los reguladores del crecimiento mejoran la calidad de la rosa de corte.

The spider mite, Tetranychus urticae Koch., is one of the most important pests of cut rose (Rosa x hybrida) in the State of México and, its primary control it's through the use of acaricides, such as propargite; the producers initially used it with satisfactory results and currently it does not control this pest anymore. In order to estimate the level of resistance to that acaricide, in 2007, its response to this acaricide was assessed in populations from Coatepec Harinas, Tenancingo, Villa Guerrero and Zumpahuacán, State of México. In each locality at least 4 000 nymphs and 2 000 adults were collected in the cut rose cultivation in greenhouses and were reproduced to F1 for the bioassays. The dose range that eliminated 0 to 100% of the treated individuals was determined (biological window). Subsequently, from five to seven concentrations were included covering the range. Five repetitions were made, four in different consecutive days. Spider mite populations from Coatepec Harinas (RR95= 7.9X, Villa Guerrero (RR95= 1.3 X and Zumpahuacán (RR95= 11X) are considered susceptible to propargite; while the population of Tenancingo (RR95= 90. IX) is considered resistant to the acaricide.

Resumen La araña roja, Tetranychus urticae Koch., es una de las plagas más importantes de la rosa de corte, (Rosa x hybrida), en el Estado de México y su combate se realiza principalmente mediante el uso de acaricidas como el propargite; mismo que los productores usaron inicialmente con resultados satisfactorios y actualmente no controla esta plaga. Con el objetivo de estimar el nivel de resistencia a dicho acaricida, en el año 2007 se evaluó su respuesta a dicho acaricida en poblaciones provenientes de Coatepec Harinas, Tenancingo, Villa Guerrero y Zumpahuacán, Estado de México. De cada localidad se recolectaron al menos 4000 ninfas y 2 000 adultos en el cultivo de rosa de corte bajo invernadero y se reprodujeron hasta F1 para realizar los bioensayos. Se determinó el rango de dosis que eliminaba el 0 al 100% de los individuos tratados (ventana biológica). Posteriormente se incluyeron de cinco a siete concentraciones que cubrieron dicho rango. Se realizaron cinco repeticiones cuatro en días consecutivos diferentes. Las poblaciones de araña roja provenientes de Coatepec Harinas (RR95= 7.9x), Villa Guerrero (RR95=1.3x) y Zumpahuacán (RR95= 11 x) se consideran susceptibles a propargite; mientras que la población de Tenancingo (RR95 = 90.1 x) se considera resistente a dicho acaricida.

El sistema tradicional para producir botones florales de rosa de corte es ineficiente en las zonas productoras del estado de México, ya que muy pocos de ellos logran una alta calidad. El presente trabajo tuvo el objetivo de evaluar el uso de protectores florales solos o impregnados con fitohormonas (giberelinas o citocininas) para aumentar la calidad del botón floral. El protector floral impidió el ingreso de trips al botón floral e incrementó la calidad del botón floral tanto en la variedad Black Magic como en la Polo. El protector floral solo y con giberelinas contribuyó a aumentar la calidad del botón floral. Las citocininas utilizadas para impregnar tanto el botón floral como el protector floral aumentaron la calidad del botón en dosis óptima de 0,001 mg·L-1; sin embargo, dosis iguales o mayores a 100 mg·L-1 dañaron la estructura floral.

The present study was conducted to assess the use of floral protectors alone or impregnated with phytohormones (gibberellins or cytokinins) to increase bud quality. The floral protectors prevented the entry of thrips to the flower bud and increased the flower bud quality in the varieties Black Magic and Polo. The floral protector alone and gibberellin impregnated contributed to increase the quality of the floral buds. Cytokinins used to impregnate both the bud and the protector increased the quality of the floral buds at the optimal dosage of 0.001 mg·L-1; however, doses equal or above 100 mg·L-1 damaged the floral structure.

Gynaikothrips ficorum (Marchal) is a pest of the laurel tree in urban zones and insecticides are possibly used for its control, but its initial response to these products is unknown. Therefore susceptibility of various populations of this species was determined (Texcoco, Córdoba and Tlayacapan) to the insecticides permethrin, cypermethrin, diazinón, malathion, methyl oxydemeton, methyl parathion, endosulfán and methomyl. The Texcoco population was used as reference to make comparisons of the response. At 24 h of exposure, the confidence levels of the CL50 of the three populations overlapped in the insecticides cypermethrin, diazinón, malathion and methyl oxydemeton; but they did not overlap in Córdoba and Tlayacapan with Texcoco, for permethrin, methyl parathion, endosulfán and methomyl. For Córdoba and Tlayacapan with cypermethrin, the resistance proportion (RP50) was 0.88 and 0.53'; with diazinón, 0.3 and 0.29'; with malathion 1.04 and 1.02'; with methyl oxydemoton 0.74 and 7.18'; with methyl parathion 8.4 and 4.63'; with endosulfán 1.19 and 0.2', and with methomyl 0.11 and 0.53'. At 95 % mortality, only in Tlayacapan and for endosulfán (RP95=0.03), the fiducial limits did not overlap with the other two populations. The values obtained at 48 h of exposure followed the same tendencies found at 24 h. These response values correspond to a susceptible state and can be used as comparison reference.

Gynaikothrips ficorum (Marchal) es una plaga del laurel en zonas urbanas y posiblemente se usan insecticidas para su control, pero se desconoce su respuesta inicial a éstos. Por tanto, se determinó la susceptibilidad de varias poblaciones de esta especie (Texcoco, Córdoba y Tlayacapan) a los insecticidas permetrina, cipermetrina, diazinón, malatión, oxidemetón metílico, paratión metílico, endosulfán y metomil. La población Texcoco se usó como referencia para hacer comparaciones de la respuesta. A las 24 h de exposición, los límites de confianza de la CL50 de las tres poblaciones se traslaparon en los insecticidas cipermetrina, diazinón, malatión y oxidemetón metílico; pero no se traslaparon en Córdoba y Tlayacapan con Texcoco, para permetrina, paratión metílico, endosulfán y metomil. Para Córdoba y Tlayacapan con cipermetrina, la proporción de resistencia (PR50) fue 0.88 y 0.53'; con diazinón 0.3 y 0.29'; con malatión 1.04 y 1.02'; con oxidemetón metílico 0.74 y 0.9'; con permetrina 5 y 7.18'; con paratión metílico 8.4 y 4.63'; con endosulfán 1.19 y 0.2', y con metomil 0.11 y 0.53'. A nivel del 95 % de mortalidad, sólo en Tlayacapan y para endosulfán (PR95 =0.03), los límites fiduciales no se traslaparon con las otras dos poblaciones. Los valores obtenidos a las 48 h de exposición siguieron las mismas tendencias encontradas a las 24 h. Estos valores de respuesta corresponden a un estado susceptible y se podrán usar como referencia de comparación.

Spiromesifen is an insecticide that inhibits the synthesis of lipids and, in Mexico, its use against the Tomato-Potato Psyllid, Bactericera cockerelli (Sulc), on chili pepper (Capsicum annum), tomato (Lycopersicon sculentum) and potato (Solanum tuberosum) began in 2005; however more information is needed to understand its toxicity on this insect pest. The aim of this research was to determine the toxicity of spiromesifen against each of the biological stages of tomato-potato psyllid, its effect on fertility and viability of eggs deposited by treated females, as well as the female preference to lay eggs on treated and non treated plants. The relative toxicity at 95% mortality (highest LC95 value /LC95 value of the respective biological stage) of spiromesifen in egg, nymph 1, nymph 2, nymph 3, nymph 4, and nymph 5 were 517.5; 31316.2; 2950.1; 315.6; 18.2 and 1-fold, respectively. There were no differences in the toxicity of spiromesifen between adult males and females. The number of laid eggs was reduced as the spiromesifen concentration used to treat female increased and egg hatch was reduced in all tested doses. In the "no choice" test, females deposited 38.6 ± 2.01 eggs by leaf of non treated chili pepper type jalapeño, while in the treated with 360 mg L-1 we observed 0.3 ± 0.08 eggs by leaf. In the "choice" test, the oviposition decreased as the dose increased. There were no eggs on plants treated with 2400 mg L-1 of spiromesifen.

In two field-collected populations of de Bemisia tabaci (Gennadius) B biotype previously selected with the neonicotinoid insecticide thiamethoxam (NEO-R, NEO-N), and a population susceptible to insecticides (SUSC), the level of response to the insecticide thiametoxam, as well as the life and fertility tables were determined. At LC95, the NEO-R population showed a resistance ratio (RR95) value of 8.8-fold, an intrinsic rate of increase (r m) of 0.72. The fitness of the NEO-R and NEO-N populations in relation to the SUSC was 1.5 and 2.0, respectively. The RR95 value for NEO-N was 1.9-fold; it's r m value was 0.082, while in the SUSC population was 0.041. The developmental time of egg and adult were longer in NEO-R population, while the nymph and pupa lasted longer in the NEO-N and SUSC populations. The developmental time was different in the three NEO-R, NEO-N, and SUSC populations with 19.7 d (315.84 degree days or dd), 15.7 d (250.4 dd) and 18.5 d (296.6 d), respectively. The populations previously selected with thiamethoxam did not reproduce faster than their susceptible counterpart.

The rational use of insecticides requires previous evaluation of the effectiveness of the chemicals to be used. This may reduce the use of non-effective products and prevent rising production costs and pollution. To facilitate bioassays in the laboratory, susceptibility values (LD50) of 64 insecticides and acaricides for 33 species of arthropods are presented. These LD50 could be used to determine susceptibility or resistance of these species in México.

La utilización racional de insecticidas contra una plaga en un cultivo determinado requiere de la evaluación previa de la efectividad de los productos a emplear. Esto puede disminuir el uso de productos no efectivos que encarecen la producción y contaminan el medio. Para facilitar los bioensayos en el laboratorio, se presentan los valores de susceptibilidad (DL50) para 64 insecticidas y acaricidas en 33 especies de artrópodos. Estos DL50 se podrían usar para determinar susceptibilidad o resistencia de esas especies en México.

The tomato-potato psyllid, Bactericera cockerelli (Sulc.), is one of the most important pests of chili pepper (Capsicum spp.), tomato (Lycopersicon esculentum Mill.), and potato (Solanum tuberosum L.) in México. Insecticides are used for its control, and the farmers perceive that their biological effectiveness is not satisfactory. In nymphs, LC50, LC95, confidence limits at 95%, values of resistance ratio at a level of LC50 (RR50) and LC95 (RR95) to six insecticides were determined in one susceptible and two field-collected populations (El Huizache, State of San Luis Potosí, and Arteaga-Galeana of Coahuila and Nuevo León). All the populations were susceptible to fenpropathrin, abamectin, cyfluthrin, dimetoate, esfenvalerate, and pyriproxyfen. It is documented that the lack of biological effectiveness in field is not due to resistance to insecticides.

El salerillo, Bactericera cockerelli (Sulc) es una de las plagas más importante del chile (Capsicum spp.), jitomate (Lycopersicon esculentum Mill.) y papa (Solanum tuberosum L.) en México. Para su control se usan insecticidas y los agricultores perciben que su eficacia biológica no es satisfactoria. En ninfas se determinaron los valores de CL50, CL95, límites de confianza al 95% y valores de proporción de resistencia a nivel de CL50 (RR50) y CL95 (RR95) a seis insecticidas en una población susceptible y dos de campo (El Huizache, Estado de San Luis Potosí, y Arteaga-Galeana de Coahuila y Nuevo León). Todas las poblaciones fueron susceptibles a fenpropatrín, abamectina, cyfluthrín, dimetoato, esfenvalerato y pyriproxyfen. Se documenta que la falta de eficacia biológica en campo no se debe a la resistencia a insecticidas.

Se determinó la susceptibilidad a los insecticidas acetamiprid, cipermetrina, imidacloprid, pymetrozina y thiamethoxam en dos poblaciones de mosquita blanca, Bemisia tabaci (Gennadius), Biotipo B, colectadas en los estados de Baja California y Sinaloa, México. En relación a una población susceptible, a nivel de 50% de mortalidad, la proporción de resistencia (RR50) más elevada se presentó en la población de Sinaloa a cipermetrina (17,2×), pymetrozine (26,9×) e imidacloprid (42,8×). Sin embargo, a 95% de mortalidad, las dos poblaciones fueron susceptibles a los insecticidas evaluados.

Susceptibility to acetamiprid, cypermethrin, imidacloprid, pymetrozine and thiamethoxam was determined in two populations of sweet potato whitefly Bemisia tabaci (Gennadius), Biotype B, collected in the states of Baja California and Sinaloa, Mexico. In comparison to a susceptible population, at 50% mortality, the highest resistance ratios (RR50) were observed in the Sinaloa population to cypermethrin (17.2×), pymetrozine (26.9×) and imidacloprid (42.8×). However, at 95% mortality, both populations were susceptible to the evaluated insecticides.

Determinou-se a susceptibilidade aos inseticidas acetamiprid, cipermetrina, imidacloprid, pymetrozine e thiamethoxam em duas populações de mosca branca Bemisia tabaci (Gennadius), Biotipo B, coletadas nos estados da Baixa Califórnia e Sinaloa, México. Em relação a uma população susceptível, ao nível de 50% de mortalidade, a população de sinaloa apresentou a proporção de resistência (RR50) mais elevada à cipermetrina (17,2×), pymetrozine (26,9×) e imidacloprid (42,8×). No entanto, aos 95% de mortalidade, as duas populações foram susceptíveis aos inseticidas avaliados.