ABSTRACT: One of the causes of productivity loss in sugarcane cultivation has been associated with the species Diatraea saccharalis, also known as the sugarcane borer. Therefore, this study evaluated the feasibility of using hyperspectral sensors to obtain the leaf spectral response of sugarcane in different periods of infestation at leaf and canopy levels to diagnose D. saccharalis damage in advance. The study included three varieties of sugarcane: CTC9003BT, CTC4, and RB966928. The insecticide Altacor® was used to control pestsin half of the plots. Data collection occurred at the following stages: sprouting, tillering, stalke longation, and early maturation. Data regarding relative water content (RWC), leaf spectral signature in the laboratory and canopy, vegetation indices (NDVI and MCARI), productivity, purity, and total recoverable sugar (TRS) were collected to evaluate the borer effects on the sugarcane crop. The highest RWC was observed for CTC9003BT (60.15%) without insecticide and 59.0% with insecticide. The visible (400-680 nm) and near-infrared (750-1300 nm) spectral bands identified spectral variations in plants with and without sugarcane borer. The percentage of sugarcane borer showed high and negative correlations between productivity, NDVI, and TRS, with coefficients of -0.68, -0.76, and -0.76, respectively. The NDVI and MCARI indices effectively detect plants under stress, but their variation is influenced by multiple factors, making it difficult to associate them with a single problem (sugarcane borer). ABSTRACT Therefore D advance CTCBT CTC BT CTC4 RB966928 RB Altacor plots stages sprouting tillering longation maturation RWC, , (RWC) MCARI, MCARI) purity TRS (TRS crop 60.15% 6015 60 15 (60.15% 590 59 0 59.0 400680 400 680 (400-68 nm nearinfrared near infrared 7501300 750 1300 (750-130 0.68, 068 68 -0.68 0.76, 076 76 -0.76 respectively stress factors . borer) RB96692 (RWC 60.15 601 6 1 (60.15 5 59. 40068 40 (400-6 750130 75 130 (750-13 0.68 06 -0.6 0.76 07 7 -0.7 RB9669 60.1 (60.1 4006 4 (400- 75013 13 (750-1 0.6 -0. 0.7 RB966 60. (60. (400 7501 (750- 0. -0 RB96 (60 (40 (750 - RB9 (6 (4 (75 ( (7

RESUMO: Uma das causas de perda de produtividade em lavouras de cana está associada à espécie Diatraea saccharalis, também conhecida por broca da cana. Portanto, este estudo avaliou a viabilidade do uso de sensores hiperespectrais para obter a resposta espectral foliar da cana-de-açúcar em diferentes períodos de infestações, tanto a nível foliar quanto dossel, a fim de diagnosticar antecipadamente os danos da Diatraea saccharalis. O estudo contou com três variedades de cana-de-açúcar: CTC9003BT, CTC4 e RB966928. Em metade das parcelas foi utilizado o inseticida Altacor® para o controle de pragas. As coletas de dados ocorreram nas fases: brotação, perfilhamento, crescimento de colmos e início da maturação. Para avaliar os efeitos da broca na cana foi coletado os dados referentes ao conteúdo relativo de água (CRA), assinatura espectral foliar em laboratório e dossel, índices de vegetação (NDVI e MCARI), produtividade, pureza e ATR (Açúcar Total Recuperável). O maior CRA encontrado foi para a CTC9003BT (60,15%) sem inseticida e 59,0% com inseticida. As faixas espectrais do visível (400-680 nm) e infravermelho próximo (750-1300 nm) identificaram variações espectrais nas plantas com e sem broca. O percentual de broca apresentou correlações altas e negativas entre a produtividade, NDVI e ATR, com coeficientes de -0,68, -0,76 e -0,76, respectivamente. Os índices NDVI e MCARI foram eficazes na detecção de plantas sob estresse, contudo, sua variação é influenciada por múltiplos fatores, sendo difícil associá-los a um único problema (broca). RESUMO saccharalis Portanto canadeaçúcar açúcar infestações dossel CTCBT CTC BT RB966928 RB Altacor pragas fases brotação perfilhamento maturação CRA, , (CRA) MCARI, MCARI) Açúcar Recuperável. Recuperável . Recuperável) 60,15% 6015 60 15 (60,15% 590 59 0 59,0 400680 400 680 (400-68 nm 7501300 750 1300 (750-130 0,68, 068 68 -0,68 0,76 076 76 -0,7 0,76, respectivamente estresse contudo fatores associálos associá los (broca) RB96692 (CRA 60,15 601 6 1 (60,15 5 59, 40068 40 (400-6 750130 75 130 (750-13 0,68 06 -0,6 0,7 07 7 -0, (broca RB9669 60,1 (60,1 4006 4 (400- 75013 13 (750-1 0,6 0, -0 RB966 60, (60, (400 7501 (750- - RB96 (60 (40 (750 RB9 (6 (4 (75 ( (7

Resumo O menor teor de lignina em espécies de plantas com potencial energético resulta na maior facilidade de quebra da celulose, disponibilizando glicose para geração de etanol. Porém, maiores teores de lignina representa um fator de resistência ao ataque de insetos. O objetivo deste trabalho foi avaliar como importantes pragas do sorgo energia, Diatraea saccharalis e Spodoptera frugiperda, se comportam quanto à alimentação e desempenho em sorgo bmr-6, um genótipo mutante com menor concentração de lignina. Foram realizados experimentos em laboratório e casa de vegetação, avaliando o desenvolvimento destas pragas nos híbridos de sorgo biomassa bmr 007, 008, TX635 e seus respectivos genótipos isogênicos convencionais (sem o gene bmr). O teor de lignina foi maior nos híbridos não bmr, mas nos parâmetros avaliados nos insetos, houve variação entre os tratamentos, não sendo consistente em apenas um híbrido e nem por ser ou não bmr. A menor sobrevivência de S. frugiperda foi verificada no híbrido BR008 tanto bmr quanto não bmr. As notas de injúria por S. frugiperda no sorgo em casa de vegetação foram altas (>7) em todos os tratamentos. Para D. saccharalis, não houve diferença significativa para a sobrevivência larval em laboratório, mas em casa de vegetação o híbrido BR007 tanto bmr quanto não bmr proporcionaram maior sobrevivência. Diante da necessidade de diversificar a matriz energética e o fato de que não foi comprovada neste estudo maior suscetibilidade dos híbridos bmr a ambas as pragas, estes resultados são promissores para o cultivo desses híbridos de sorgo biomassa para produção de biocombustíveis.

Abstract The lower lignin content in plants species with energy potential results in easier cellulose breakdown, making glucose available for ethanol generation. However, higher lignin levels can increase resistance to insect attack. The objective of this work was to evaluate the susceptibility of a bmr-6 biomass sorghum (a mutant genotype with a lower concentration of lignin) to important pests of energy sorghum, Diatraea saccharalis and Spodoptera frugiperda. Experiments were performed in the laboratory and greenhouse to evaluate the development of these pests on the biomass sorghum bmr hybrids BR007, BR008, and TX635 and their respective conventional near-isogenic genotypes (without the bmr gene). The lignin content was higher in non-bmr hybrids, but the evaluated insect variables varied between treatments, not being consistent in just one hybrid or because it is bmr or not. The lowest survival of S. frugiperda was observed in the BR008 hybrid, both bmr and non-bmr. The S. frugiperda injury scores on plants in the greenhouse were high (>7) in all treatments. For D. saccharalis, there was no difference in larval survival in the laboratory, but in the greenhouse, the BR007 hybrid, both bmr and non-bmr, provided greater survival. Due the need to diversify the energy matrix and the fact that greater susceptibility of the bmr hybrids to either pests was not found in this study, these results hold promise for cultivation of these biomass sorghum hybrids for the production of biofuels.

ABSTRACT. Cotesia flavipes parasitizes Diatraea saccharalis, a pest that causes major losses to sugarcane production. The mass production of C. flavipes and its subsequent release onto sugarcane is one form of biological control of D. saccharalis. An essential factor for successfully fighting this pest is the development of host diets that can increase the efficiency of C. flavipes production. Palm oil contains saturated fatty acids, unsaturated fatty acids, and polyunsaturated linoleic acid. However, little is known about the effects of palm oil on C. flavipes production in the laboratory. Different concentrations of palm oil were added to the D. saccharalis diet and its nutritional indices were analyzed. Subsequently, the production and sex ratio of C. flavipes were determined. Our results indicated that the addition of higher palm oil concentrations to an artificial diet generated a high relative consumption rate (RCR) in D. saccharalis, and consequently a high relative metabolic rate (RMR), which resulted in a lower production of the parasitoid. In contrast, the lowest palm oil concentration in the artificial diet generated a low RMR and resulted in high-efficiency conversion of ingested food (ECI), enabling D. saccharalis to yield more C. flavipes. This suggests that palm oil influences the quantity of D. saccharalis ingested, which determines the number of C. flavipes that will be generated. In this study, supplementation of a D. saccharalis diet with 0.25% palm oil increased the production of C. flavipes. Therefore, this level of palm oil supplementation can aid in the production of C. flavipes on a laboratory-scale. Further research, including increasing the number of parasitoids, must be performed to mass-produce the augmentative releases of C. flavipes to manage D. saccharalis. ABSTRACT C D acids acid However laboratory analyzed Subsequently determined RCR (RCR RMR, , (RMR) parasitoid contrast highefficiency ECI, ECI (ECI) study 025 0 25 0.25 Therefore laboratoryscale. laboratoryscale scale. scale laboratory-scale research parasitoids massproduce produce (RMR (ECI 02 2 0.2 0.

ABSTRACT: Sugarcane borer Diatraea saccharalis (F.) is the primary sugarcane pest in Brazil. To estimate the relationship between larvae in sugarcane stalks and captures of male adults of D. saccharalis, we collected samples weekly: (1) adults with one delta trap with three virgin females and three female pupae and (2) larvae in 120 stalks per plot of 12.6 hectares (355 × 355 m). The study was conducted in two sites with five plots each, in the municipalities of Nova Ponte and Tupaciguara, Minas Gerais State, Brazil, from July 2016 to May 2017. Relationships between (1) males trapped per week and the number of larvae outside of stalks (LOS) were estimated and (2) we evaluated climate variables, namely average temperature, average relative air humidity, hours with relative air humidity below 30 %, rainfall and number of rainy days, and adults and larvae of D. saccharalis. We obtained generalized linear models for LOS in autumn and for larvae inside the stalks (LIS) in spring and autumn and trapped males in both sites. A significant and direct relationship between LIS and males trapped allows predicting larvae density based on captures of males. In addition, plant damage can be estimated based on accumulated captures of males. There was a negative relationship between hours of air humidity < 30 % and larvae outside of stalks. Densities of LIS can be estimated from male captures and by the humidity variables in the trapping week. Nevertheless, the models require validation in the field.

ABSTRACT Plant resistance is an important tactic within the precepts of Integrated Pest Management, and the existence of grain sorghum hybrids with multiple insect resistance could benefit crop management and sustainability. This study evaluated the susceptibility of 30 grain-sorghum hybrids to three major pests, namely, fall armyworm (FAW) Spodoptera frugiperda, sugarcane borer (SCB) Diatraea saccharalis, and green-belly stink bug (GBS) Diceraeus melacanthus. The hybrids were cultivated and experiments with each insect species were conducted separately in a greenhouse. For FAW, visual injury assessments were performed on plants 7 and 14 days after infestation (DAI). For SCB, insect presence and injury were assessed 40 DAI. For GBS, the plants were evaluated using a damage rating scale 12, 19, and 26 DAI. Cluster analysis allowed separating the grain sorghum hybrids into groups regarding the levels of resistance to each pest. Hybrid BRS373 stood out as moderately resistant to FAW; AG1090, 80G20, BRAVO, BRS373, AG1615, and IG220 were the most promising for SCB; and for GBS, hybrids 50A40, A9735R, JADE, ENFORCER, BUSTER, 50A10, and IG244 were the most nominated. This information will significantly aid sorghum breeding programs focused on developing commercial hybrids that comprise both insect-resistance and high-yield characteristics. However, further research should evaluate potential chemical and morphological plant traits underlying the lower levels of susceptibility to FAW, SCB, and GBS found in the selected sorghum hybrids. Management sustainability 3 grainsorghum pests namely FAW (FAW frugiperda SCB (SCB saccharalis greenbelly green belly (GBS melacanthus greenhouse 1 DAI . (DAI) 4 12 19 2 pest BRS BRS37 AG1090 AG 80G20 G BRAVO AG1615 IG IG22 50A40 A A9735R AR R JADE ENFORCER BUSTER 50A10 IG24 nominated insectresistance highyield high yield characteristics However (DAI BRS3 AG109 80G2 AG161 IG2 50A4 50A1 AG10 80G AG16 50A AG1

ABSTRACT Fungal virulence is multifaceted and dependent on multiple factors including the pH of the spore suspension. In this study, we accessed effects of six pH values of Beauveria bassiana, and Metarhizium anisopliae medium for the growth, sporulation, and mortality on sugarcane stalk borer Diatraea saccharalis. The culture of fungi was performed onplates containing the PDA (Potato Dextrose Agar) medium. Virulence was tested in D. saccharalis larvae distributed in four replicates of 15 larvae. To evaluate the performance of the isolates, they were grown at different pH values in an artificial chitin medium to confirm the degradation capacity of the fungi at each pH. No significant difference was observed for the sporulation at pH ranged from 4 to 9 for both fungi. In the mortality assay, larval mortality was higher at pH 7 and 8 for both fungi, reaching 87% for B. bassiana and 81% for M. anisopliae.

ABSTRACT: Studies on aggressiveness of parasitoids, as assessed by their parasitism against pests, used in biological-control programs are highly important to select the most suitable species and/or strain to control insect pests. The present study investigated whether the egg parasitoid Trichogramma galloi Zucchi, an efficient control agent for sugarcane borer Diatraea saccharalis (Fabricius) in Brazil, could be replaced by Trichogramma atopovirilia Oatman & Platner, a parasitoid easier to mass-produce, since it has been found parasitizing D. saccharalis eggs in the warmest region of Brazil and Argentina. Three strains of the genus Trichogramma were compared: T. atopovirilia (ATP strain) reared on a factitious host Anagasta kuehniella (Zeller); T. atopovirilia isoline ATP-I, reared on D. saccharalis eggs for six generations; and T. galloi, reared on A. kuehniella eggs. We measured parasitism of each strain for 72 h and for the entire life span, parasitism rate per cluster of D. saccharalis eggs, number of parasitoids emerged (parasitism viability), and parasitoid life span. The results confirmed that T. galloi is the best species for D. saccharalis control, showing higher control potential, since parasitism and emergence rate were higher for this species. Although T. atopovirilia ATP-I performed reliably in all parameters, T. galloi exceeded and was the most indicated for mass-rearing in control programs for sugarcane borer.

ABSTRACT The development and use of microbial pesticides for the control of agricultural pests has intensified in recent years due to the increasing need for reductions in the use of highly toxic agrochemicals. To fill this growing need for biopesticides it is necessary to develop suitable formulations that stabilize microorganisms against environmental stress factors that reduce their efficacy and persistence in the field. In this context, the objective of the present work was to determine the insecticidal activity and persistence on sugarcane plants, of an emulsifiable concentrate (EC) containing Beauveria bassiana for the control of sugarcane borer, Diatraea sp. Photostability of the formulation under UV radiation type B and the mean and ninety lethal concentrations were also determined under laboratory conditions. The EC reached more than 80% efficacy against D. saccharalis larvae under semi-controlled field conditions. The EC efficiently photostabilized the conidia, maintaining 68.9% germination after nine minutes of irradiation while unformulated conidia completely lost the ability to germinate. This effect was also observed for the insecticidal activity, with unformulated conidia losing 30% more efficacy than formulated conidia after nine minutes of irradiation. The insecticidal activity and conidia count on sugarcane plants under field conditions decreased one and two weeks post application, respectively. Although the EC containing on B. bassiana demonstrated effective insecticidal activity against D. saccharalis, it is necessary to carry out field trials to optimize the formulation and determine the method and frequency of application to maximize its performance.

RESUMEN El desarrollo y uso de plaguicidas microbianos para el control de plagas agrícolas se ha intensificado en los últimos años, debido a la creciente necesidad de reducir el uso de agroquímicos de alta toxicidad. Pero para suplir esta creciente necesidad de bioplaguicidas, es necesario desarrollar formulaciones adecuadas que estabilicen a los microorganismos frente a los factores ambientales de estrés que reducen su eficacia y persistencia de en campo. En este contexto, el objetivo del presente trabajo fue determinar la actividad insecticida y persistencia en plantas de caña de un concentrado emulsionable (CE) a base de Beauveria bassiana para el control del barrenador de la caña, Diatraea sp. La fotoestabilidad frente a la radiación UV tipo B y las concentraciones letales media y noventa del bioplaguicida también se determinaron bajo condiciones de laboratorio. El CE presentó una eficacia superior al 80% para el control de larvas de D. saccharalis bajo condiciones semicontroladas de campo. La formulación fotoestabilizó eficientemente los conidios, manteniendo un 68,9% de germinación después de nueve minutos de irradiación, mientras que los conidios sin formular perdieron completamente la capacidad de germinar. Este efecto también se observó para la actividad insecticida, ya que los conidios sin formular perdieron un 30% más de eficacia que los conidios formulados, después de nueve minutos de irradiación. La actividad insecticida y el recuento de conidios en plantas de caña de azúcar en campo disminuyeron a partir de la primera y segunda semana después de la aplicación, respectivamente. Aunque el CE a base de B. bassiana demostró una efectiva actividad insecticida contra D. saccharalis, es necesario realizar estudios de campo para optimizar la formulación y determinar el método y frecuencia de aplicación que permitan maximizar su desempeño.

Abstract The fluctuation of insect pests in 16 corn genotypes was evaluated, the relationship between the number of insects and grain yield was analyzed, and the most important pests for the conditions of the Campo Verde district in Pucallpa, Ucayali region were identified. 16 genotypes of hard yellow corn were evaluated under a randomized complete block design with three replications; each plot had 72 plants planted at a density of 62,500 plants per hectare. The experiment was carried out in the Campo Verde district, Coronel Portillo province, Ucayali department, Peru. Through the systematic sampling of pests, 15 plants were randomly taken per genotype in which the insects present in them were counted. In total, 12 evaluations were carried out at 10, 18, 26, 34, 41, 48, 54, 62, 69, 75, 84 and 96 days after sowing (dds). Six pests out of a total of seven were the most frequently obtained during the crop cycle, which were identified as: Dalbulus maidis (De Long and Wolcott) (Hemiptera: Cicadellidae), Diabrotica viridula (Fabricius) (Coleoptera: Chrysomelidae), Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae), Empoasca kraemeri (Ross and Moore) (Hemiptera: Cicadellidae), Oliarus spp. (Hemiptera: Cixiidae) and Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). On average, of the 12 evaluations carried out on the 16 genotypes, four were the moments in which the highest number of insects per plant was recorded (26, 34, 54 and 96 dds). The regression lines turned out to be not significant; however, the negative relationship between the number of insects and grain yield is evident. Apparently, the three most important pests would be: S. frugiperda, followed by D. maidis and D. viridula, since without these pests the average yield of the 16 genotypes would rise from 2.16 t / ha to 3.1; 2.98 and 2.81 t / ha, respectively.

Resumen Se evaluó la fluctuación de insectos plagas en 16 genotipos de maiz, se analizó la relación entre el número de insectos y el rendimiento de grano, y se identificaron las plagas más importantes para las condiciones del distrito de Campo Verde en Pucallpa, región Ucayali. 16 genotipos de maiz amarillo duro fueron evaluados bajo el diseño de bloques completos al azar con tres repeticiones; cada parcela tuvo 72 plantas sembradas a una densidad de 62.500 plantas por hectárea. El experimento se realizó en el distrito de Campo Verde, provincia de Coronel Portillo, departamento de Ucayali, Perú. Mediante el muestreo sistemático de plagas, se tomaron 15 plantas por genotipo al azar en las que se contaron los insectos presentes en ellas. En total, se realizaron 12 evaluaciones a los 10, 18, 26, 34, 41, 48, 54, 62, 69, 75, 84 y 96 dias después de la siembra (dds). Seis plagas de un total de siete fueron obtenidas con más frecuencia durante el ciclo del cultivo, las que se identificaron como: Dalbulus maidis (De Long y Wolcott) (Hemiptera: Cicadellidae), Diabrotica viridula (Fabricius) (Coleoptera: Chrysomelidae), Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae), Empoasca kraemeri (Ross y Moore) (Hemiptera: Cicadellidae), Oliarus spp. (Hemiptera: Cixiidae) y Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). En promedio, de las 12 evaluaciones realizadas sobre los 16 genotipos, cuatro fueron los momentos en los que se registró el mayor número de insectos por planta (26, 34, 54 y 96 dds). Las lineas de regresión resultaron no ser significativas; sin embargo, es evidente la relación negativa entre el número de insectos y el rendimiento de grano. Aparentemente, las tres plagas más importantes serian: S. frugiperda, seguida de D. maidis y D. viridula, ya que sin estas plagas el rendimiento promedio de los 16 genotipos subiría de 2,16 t/ha a 3,1; 2,98 y 2,81 t/ha, respectivamente.

The sugarcane borer, Diatraea saccharalis (Fabricius), is the major pest insect attacking sugarcane crops in Brazil. Population control by insecticide treatment is not efficient due to simultaneous presence of all developmental stages of the insect throughout the year, and alternative control methods are needed. Two female-produced sex pheromone components, (Z,E)-hexadeca-9,11-dienal and (Z)-hexadec-11-enal, have previously been reported to elicit antennal activity and behavioral response of males in flight tunnel experiments. However, the attractiveness of these compounds in field tests has been very low. In this study, two additional female-produced compounds in D. saccharalis eliciting consistent antennal response in males were identified as (Z)-hexadec-9-enal and hexadecanal. In flight tunnel assays, the behavioral response to a quaternary blend was significantly higher when compared with the previously identified binary blend. Subtracting (Z)-hexadec-9-enal or hexadecanal from the full blend did not reduce attraction, indicating redundancy in the communication channel. We conclude that additional compounds are part of the sex pheromone of D. saccharalis, which may improve the efficiency of trap lures for monitoring of this pest.

Resumen Los hongos entomopatógenos Metarhizium anisopliae (Ascomycota: Clavicipitaceae) y Beauveria bassiana (Ascomycota: Cordycipitaceae) son una alternativa para el control de plagas de gramíneas (e.g. Rhammatocerus schistocercoides (Orthoptera: Acrididae) y de soya (e.g. Cerotoma tingomariana; Coleoptera: Chrysomelidae). Con el fin de utilizar estos microorganismos como principio activo de micoinsecticidas, es necesario contar con métodos de control de calidad microbiológico, fisicoquímico y de actividad biológica que sean repetibles y reproducibles en el tiempo. Por tal razón, y dada la dificultad en la recolecta de individuos en el campo y en el establecimiento de crías masivas de R. schistocercoides y de C. tingomariana, se establecieron métodos para la evaluación rutinaria de la actividad biológica mediante el uso de hospederos alternativos. Para M. anisopliae, dirigido al control de R. schistocercoides, se evaluaron las especies Diatraea saccharalis (Lepidoptera: Crambidae) y Spodoptera frugiperda (Lepidoptera: Noctuidae) mientras que para B. bassiana, dirigido al control del insecto C. tingomariana, se evaluaron D. saccharalisy Chloridea virescens(Lepidoptera: Noctuidae). Se seleccionaron a D. saccharalis y C. virescens como insectos alternativos para evaluar la eficacia de M. anisopliae y B. bassiana, respectivamente con eficacia cercana al 80 %, en los dos casos. Los métodos con los insectos alternativos seleccionados fueron estandarizados y se demostró que son repetibles y reproducibles bajo las condiciones evaluadas.

Abstract The entomopathogenic fungi Metarhizium anisopliae (Ascomycota: Clavicipitaceae) and Beauveria bassiana (Ascomycota: Cordycipitaceae) are an alternative for the control of grassland pests (e.g. Rhammatocerus schistocercoides (Orthoptera: Acrididae) and soybean pests (e.g. Cerotoma tingomariana; Coleoptera: Chrysomelidae). To use these microorganisms as active principles of micoinsecticides, it is necessary to have quality control methods (microbiological, physicochemical and biological activity) accuracy, and reproducibility in a given timeframe. For this reason and given the difficulty in obtaining individuals in the field and in the establishment of the rearing of R. schistocercoides and C. tingomariana, we established methods for the routine evaluation of biological activity using alternative hosts. For M. anisopliae directed to the control of R. schistocercoides, the model insects Diatraea saccharalis (Lepidoptera: Crambidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) were tested, and for B. bassiana directed to the control of the target insect C. tingomariana, the model insects D. saccharalis and Chloridea virescens (Lepidoptera: Noctuidae) were evaluated. D. saccharalis and C. virescens were selected as alternative insects to evaluate the efficacy of M. anisopliae and B. bassiana, respectively. Efficacy was close to 80 % for both pathogens. The methods with the selected alternative insects were standardized and showed that they are repeatable and reproducible under the evaluated conditions.

SUMMARY Diatraea saccharalis is a key pest of corn cultivation in the Pampas region of Argentina. The economic thresholds used are nominal and are not based on the current calculation of the economic injury level. The goals of this work were: to characterize the relationship between the infestation pressure of D. saccharalis and the yield of the corn crop and to calculate economic injury levels in different situations of crop development. A test was carried out with the hybrid DK696 with natural irrigation and infestation, following a split plot experimental deslgn with five sowing dates and different crop protection windows.The yield showed a linear relationship with the intensity of injury caused by D. saccharalis and this response was independent of the sowing date. Injury caused to the middle third of the plants showed the greatest ¡nfluence in the determination of yield, followed by the lower stratum, while damage to the upper stratum did not show a relationship with yield. Economic injury levels are proposed for different price scenarios.

RESUMEN Diatraea saccharalis es una plaga clave del cultivo de maíz en la reglón pampeana argentina. Los umbrales económicos que se utilizan no están basados en un cálculo actual del nivel de daño económico. Los objetivos de este trabajo fueron: caracterizar la relación existente entre presión de infestación de D. saccharalis y rendimiento del cultivo de maíz, y calcular niveles de daño económico en distintas situaciones de desarrollo del cultivo. Se realizó un ensayo con el híbrido DK696 con riego e infestación natural, siguiendo un diseño experimental de parcelas divididas con cinco fechas de siembra y distintas ventanas de protección al cultivo. El rendimiento mostró una relación lineal con la intensidad de daño medida como número de entrenudos barrenados por larvas grandes. La actividad de las larvas se concentró en el estrato medio e inferior de la planta, independientemente de la fecha de siembra y del estado fenológico en que comenzó el ataque. El daño en el tercio medio de las plantas mostró la mayor influencia en la determinación del rendimiento, seguido por el estrato inferior, mientras que daños en el estrato superior no afectaron el rendimiento. Se proponen niveles de daño económico para distintos escenarios de desarrollo del cultivo.

Abstract This study aimed to investigate genetic parameters and selection strategies for sugarcane resistance to borer and determine the effects of selection for borer resistance on yield traits. The infestation index by borer (IIB) and yield traits were assessed over 3 years in 35 sugarcane clones planted in four locations in southeastern Brazil. There was no genotype × environment (year or location) interaction for borer resistance. Consequently, selection may be performed at only one location and year or by the mean of clones in several locations and/or years. The borer population affected the genotypic variance for borer resistance but when genotypic variance was significant, heritability was elevated and suitable genetic gain was achieved. Selection for borer resistance reduced the genetic gains for tons of cane per hectare, theoretical recoverable sugar, and tons of sugar per hectare; however, satisfactory selection gains for both borer resistance and yield were achieved using selection index.

RESUMO A população da lagarta Diatraea saccharalis (Lepidoptera: Crambidae) tem aumentado na cultura de cana-de-açúcar nos últimos anos. Apesar do controle deste inseto ser tradicionalmente realizado através do controle biológico, o uso de produtos fitossanitários ainda tem sido necessário. Portanto, o objetivo deste trabalho foi avaliar o desempenho de diferentes inseticidas no controle da broca da cana-de-açúcar, bem como o efeito sobre a produtividade e o açúcar total recuperável (ATR). O experimento foi conduzido no delineamento experimental de blocos ao acaso, com seis tratamentos e quatro blocos. Os tratamentos foram compostos por cinco inseticidas e um tratamento sem aplicação de inseticida. Para o cálculo do índice de infestação da D. saccharalis foram realizadas amostragens mensais a cada 30 dias, durante 12 meses. Após esse período, foi avaliado e calculado o índice de infestação final da D. saccharalis de cada tratamento. Para comparar a produtividade entre os tratamentos, foram colhidas as quatro linhas centrais de cada parcela. Assim, as amostras foram pesadas para o cálculo da produtividade (TCH) e enviadas ao laboratório para análise do açúcar total recuperável (ATR). O inseticida clorantraniliprole (350) proporcionou um menor índice de infestação da broca da cana, além de maior produtividade, em relação aos demais inseticidas. Não houve diferença significativa do parâmetro de açúcar total recuperável (ATR) entre os tratamentos.

ABSTRACT The population of the caterpillar Diatraea saccharalis (Lepidoptera: Crambidae) has increased in the crop of sugarcane in recent years. Although the control of this insect is traditionally carried out through biological control, the use of phytosanitary products has still been necessary. Therefore, the goal of this work was to evaluate the performance of different insecticides in sugarcane borer control, as well as the effect on productivity and total recoverable sugar (TRS). The experiment was conducted in a randomized experimental delineation of blocks, with six treatments and four blocks. Treatments consisted of five insecticides and one control group (without application of insecticide). For calculating the D. saccharalis infestation index, monthly samplings were performed every 30 days, for 12 months. After this period, the final D. saccharalis infestation index was evaluated and calculated for each treatment. In order to compare productivity among procedures, four central lines were collected from each plot. Thus, the samples were weighed for the productivity calculation (TCH) and sent to the laboratory for the total recoverable sugar (TRS) analysis. The chloranthraniliprole (350) insecticide provided a lower index of sugarcane borer infestation, in addition to greater productivity when compared to the other insecticides. There was no significant difference in the parameter of total recoverable sugar (TRS) among treatments.

Resumen Objetivos: Evaluar el efecto insecticida de productos alternativos para el control de D. saccharalis. Metodología: Se evaluó el efecto insecticida del caldo sulfocálcico puro, caldo sulfocálcico más ceniza, caldo sulfocálcico más extracto de tabaco y caldo sulfocálcico más ceniza más extracto de tabaco en concentraciones del 100%, 75%, 50% y 25% en larvas de D. saccharalis. Principales resultados: La mezcla de caldo sulfocálcico con extracto de tabaco en concentración del 75% ocasionó la mayor mortalidad de larvas de Diatraea, el mejor efecto se presentó durante las primeras 24 h de aplicación de los productos. Conclusiones: El caldo sulfocálcico en mezcla con extracto de tabaco al 75% representa una alternativa viable a los plaguicidas sintéticos para el control de D. saccharalis.

ABSTRACT Objectives: To evaluate the insecticidal effect of alternative products for the control of D. saccharalis. Methodology: The insecticidal effect of pure lime sulphur broth, lime sulphur broth plus ash, lime sulphur broth plus tobacco extract, and lime sulphur broth plus ash plus tobacco extract in concentrations of 100%, 75%, 50% and 25% in D. saccharalis larvae was evaluated. Main results: The mixture of lime sulphur broth with tobacco extract in 75% concentration caused the highest mortality of Diatraea larvae and the best effect occurred during the first 24 hours of application of the products. Conclusions: The lime sulphur broth mixed with 75% tobacco extract represents a viable alternative to synthetic pesticides for the control of D. saccharalis.