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In this long-term study we evaluated the diversity and seasonality of predatory insects (Diptera: Syrphidae and Asilidae) in Brachiaria decumbens monoculture and silvopastoral systems in Southeast Brazil. The study was conducted in Coronel Pacheco municipality, Minas Gerais state, Brazil, between February 2010 and January 2015. Insects were collected with malaise traps installed in both monoculture and silvopastoral systems. Specimen abundance, family diversity, seasonality assessed by circular analysis, the degrees of association between specimen number and climatic variables measured by Spearman’s correlation, and the constancy and similarities of Syrphidae and Asilidae were analyzed in the monoculture and silvopastoral systems. Eleven species of hoverflies (Diptera: Syrphidae) were collected, five and three of which were exclusive to the silvopasture and monoculture, respectively. The number of specimens within the monoculture was significantly greater than that in the silvopasture. Twenty-four species of robber flies (Diptera: Asilidae) were collected, two of which were exclusive to the monoculture and eight to the silvopasture. The abundance of robber flies in the silvopasture was not significantly different from that in the monoculture. Syrphidae diversity was greater in the monoculture and was not significantly different from robber fly family diversity. Circular analysis revealed seasonality, with the distribution grouped during dry periods for hoverflies and dispersed for robber flies. Most hoverflies and robber flies were accidental in each of the systems. Further studies on the capacity of these predator species to act as biological control agents of pasture pests are required. This study presents important and promising results for understanding the dynamics of the Syrphidae and Asilidae community in monoculture and silvopastoral systems in Brazil.

Maize (Zea mays L.) is the only reproductive and feeding host plant of the corn leafhopper Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae) in Brazil and this insect is the only vector of the causal agents of corn stunting diseases in South America. The ability of D. maidis to survive on other plant species in the absence of their host plant is an area of speculation. This study observed the ability of D. maidis to use other plant species as overwintering or shelter plants during the maize off-season in central Brazil. This study was carried out in the Embrapa Cerrados (Planaltina/DF, Brazil) experimental field in August 2017, August 2018, and September 2018, during which maize plants were not present in the field. In these months, several plant species present in the field were sampled using an entomological net. Samples of D. maidis collected were sorted out in the laboratory, identified by sex, and counted. Twenty-nine plant species belonging to nine botanical families were sampled. In all, a total of 146 D. maidis adults were collected from 17 plant species which include, 64 in August 2017, 67 in August 2018, and 15 in September 2018. Approximately 93% of these collections were made on plants of the Poaceae family. The number of D. maidis females collected were higher than the number of males in all the sampling periods. This study therefore, suggest that during the maize off-season, part of the D. maidis population can survive and shelter on other plants of the Poaceae family.

The effects of temperature in winter-spring (average 17.0 °C) and spring-summer (average 23.0 °C) seasons on the transmission and latent period of maize bushy stunt phytoplasma (MBS-phytoplasma) and corn stunt spiroplasma (CSS) (Spiroplasma kunkelii) caused by the corn leafhopper, Dalbulus maidis (DeLog and Wolcott) (Hemiptera: Cicadellidae) were evaluated in two experiments in a screenhouse in Sete Lagoas, Minas Gerais State, Brazil. Approximately 200 mollicute-free adults of D. maidis were confined on popcorn (Zea mays L. cv. IAC125) plants infected with spiroplasma and the same number of mollicute-free leafhoppers were confined on plants infected with phytoplasma. They remained on the source plants for a 6 d acquisition access period (AAP). Next, leafhoppers were fed healthy popcorn seedlings. Transmission tests were performed with one leafhopper per seedling for each mollicute, with 12 replicates, at 12, 20, 30, 40 d since the first day of AAP. In addition, at 40 d, one leafhopper with phytoplasma and another with spiroplasma were confined together on 24 popcorn seedlings. The inoculation access period (IAP) was 3 d. The temperature was recorded daily during the experimental periods. In Experiment 1, during the 40 d latent period, only 41.6% and 58.3% of plants, respectively, exposed to phytoplasma or to both mollicutes presented MBS-phytoplasma symptoms. In Experiment 2, during the 20 d latent period, some popcorn plants presented MBS-phytoplasma (16.7%) and CSS (33.3%) symptoms, whereas almost 100% of plants at the 30 and 40 d latent period presented disease symptoms. Plant symptoms and results from PCR tests indicated that MBS-phytoplasma was more tolerant to low temperatures than S. kunkelii.

The genus Cyclocephala Dejean (Coleoptera, Scarabaeidae, Dynastinae) contains approximately 350 species and is found mainly in the Neotropical region. These species function in the cycling of organic matter, act as bioindicators of environmental quality, and some species are considered agricultural pests. This study attempted to analyze the spatio-temporal distribution and diversity of Cyclocephala species across five Brazilian biomes, and to understand the factors that influence their distribution. Climatic variables (temperature, humidity, and precipitation), spatial variables (latitude, longitude, and elevation), and the landscape composition around the sampling areas were evaluated. Insects were collected using light traps in areas of native vegetation in the Amazon, Cerrado, Atlantic Rainforest, Pampa, and Caatinga biomes. Sampling was carried out monthly from June 2015 to May 2016. A total of 5695 individuals across 38 species of Cyclocephala were collected, including five species recorded for the first time in Brazil. The Amazon biome contains the greatest species richness and abundance of Cyclocephala species among all studied biomes, with 73.68% of collected species being endemic to this biome. The richness and abundance of species in this genus were influenced by climatic factors, such as temperature (and its interactions with precipitation and relative humidity) and the interaction between precipitation and relative humidity, and by spatial factors, such as longitude, but not by the percentage of vegetation remaining in the landscape. Cyclocephala species showed seasonal abundances and aggregated distribution, which varied according to the climatic characteristics of each biome.

BRS 429 is a sweet cassava cultivar with yellow pulp and technological qualities (high root yield, early maturity, and favorable plant architecture) and sensory qualities (short cooking time, little fiber, and soft texture) that make it an excellent option for cultivation in the Distrito Federal, Paraná, and São Paulo, Brazil.

BACKGROUND The entomopathogenic fungus Metarhizium rileyi is known to cause natural infections in some caterpillars. In this multiyear study, we carried out laboratory, greenhouse and three field trials with the aim of developing a sustainable option for control of the fall armyworm (FAW) in maize. Association of M. rileyi with Spodoptera frugiperda baculovirus (SfMNPV) and delivery strategies were also investigated. RESULTS The selected isolate (CG381) was effective in the laboratory at a low concentration (~ 4 × 103 conidia cm-2 ), killing >95% of FAW larvae within 8 days. In the greenhouse assay, applications of conidia suspended in water or as dry powder in maize whorls (~ 6.3 × 106 conidia per plant) produced similar larval mortalities (88%-96%). In the field trials, conventional spraying of unformulated conidia (0.6 and 1.2 × 1012 conidia ha-1 ) caused low larval mortalities (27-31%). Simultaneous application of either unformulated or oil-based formulations of M. rileyi conidia and S. frugiperda baculovirus (SfMNPV) to plant rows caused larval mortalities comparable with each of the pathogens applied alone. However, when a formulation containing both pathogens was sprayed directly into the whorls, the overall mortality of S. frugiperda larvae due to pathogens (mostly to M. rileyi infections) reached ~ 59%, twofold higher than the other treatments with conventional spraying, whereas in the control, the overall mortality was only 1%. CONCLUSION Optimizing exposure of S. frugiperda larvae to an inoculum of virulent entomopathogens through directed applications to maize whorls is critical to produce satisfactory mortality levels and is promising for integrated pest management.

The corn leafhopper Dalbulus maidis (DeLongWolcott) is one of the most important maize (Zea mays L.) pests in Latin America because of its ability to efficiently transmit pathogens [maize bushy stunt phytoplasma (MBSP) and corn stunt spiroplasma-Spiroplasma kunkelli Whitcomb et al. (CSS)] associated with corn stunt disease complex and maize rayado fino virus (MRFV). This leafhopper species, considered a secondary pest until a few years ago, was first reported in Brazil in 1938. Since 2015, corn stunt diseases have been the main phytosanitary threat to corn production in Brazil, and D. maidis has assumed the status of a key pest of the crop. In this study, we gathered pertinent information about the corn leafhopper, from the time it was first recorded in Brazil. Aspects such as origin, association with maize, bioecology, geographical distribution in the Americas, and its congeners are addressed. We present a history of studies performed with this species in the country, its importance as a pest, host plants, and survival strategies during the maize off-season. Based on the available scientific knowledge, the main management strategies for insect vectors and diseases are discussed. Finally, the main knowledge gaps for this insect vector and the prospects for future studies and actions to mitigate the damage caused by insect vectors in maize crops in Brazil are presented and discussed.

In 2009, a new pest of cassava crops was observed in the Federal District (Brazil) and identified as Eubulus (Kirsch) sp. (Coleoptera: Curculionidae). The pest is currently distributed in the states of Goiás, Minas Gerais, Mato Grosso do Sul, and Paraná. The larvae consume roots, causing the tissue to rot and making it unfit for consumption. The damage can extend to 100% of the roots. Owing to the potential losses that this pest is capable of causing, studies are needed on its biology, ecology, and future management strategies aimed at minimizing the losses, allowing the continuity of cassava cultivation in Brazil. This study reports on the occurrence of the pest in Brazilian Cerrado, its distribution in Brazil, the symptoms of its infestation and estimates the damage caused.

The corn leafhopper Dalbulus maidis is one of the most important pests of maize in Latin America. Here we report, for the first time, the natural occurrence of two fungal species infecting the adult stage of this pest. In 2020, insects killed by a pale bluish green fungus in irrigated maize fields located in Northeast Brazil were found attached to the abaxial surface of leaves. Using morphological characters and multigenic phylogeny, it was identified as Metarhizium brasiliense. In the beginning of 2021, the same pathogen was seen on adults in a maize field in the Central-Western region, alongside an entomophthoralean fungus during an epizootic. The latter pathogen was molecularly identified as a species in the genus Batkoa. The number of Batkoa-infected leafhoppers, displaying the typical swollen abdomen and extended wings, reached an average of 1.88 per maize leaf (86.42% of the sampled adults). The incidence of M. brasiliense was higher in plots in the Northeastern region (0.22 and 0.53 adult per leaf) when compared to the Central-Western region (0.04 adult per leaf). The report of D. maidis adults infected by M. brasiliense in agricultural settings located in different geographic regions and over 550 km apart indicates probable widespread occurrence of this pathogen in Brazil. Moreover, this opens the possibility of more applied biological control studies and, perhaps, the development of new tools to manage D. maidis populations.

A doença conhecida como enfezamento do milho, associada aos molicutes Spiroplasma kunkelii Whitcomb et al. e fitoplasma do milho (“maize bushy stunt phytoplasma”), tem adquirido importância crescente no Brasil nos últimos anos. Em função da expansão do cultivo do milho fora da época normal e do uso de irrigação em algumas regiões, tem ocorrido superposição dos ciclos da cultura no campo, favorecendo o aumento das populações desses patógenos bem como do inseto vetor, Dalbulus maidis. Nesta pesquisa foram realizados estudos ecológicos e de genética de populações de D. maidis para melhor compreender o seu mecanismo de sobrevivência na entressafra do milho e, com isso, aprimorar o manejo deste vetor visando ao controle do enfezamento. Por ser o milho o único hospedeiro conhecido de D. maidis no Brasil, esta cigarrinha parece ter duas alternativas para sua sobrevivência na ausência da cultura: migração e/ou dormência em restos culturais ou áreas adjacentes. Para investigar estas possibilidades, populações de D. maidis foram monitoradas quinzenalmente através de cartões adesivos amarelos dupla face (7x12 cm) por períodos que variaram de 15 a 29 meses, no município de Anastácio/MS. Esta região é caracterizada por áreas extensas de pastagens e por apresentar pequenas áreas de plantio de milho com um longo período de entressafra (6-7 meses). O monitoramento foi realizado em cinco áreas representando duas situações distintas: a) áreas (I e II) onde o milho era plantado uma vez por ano a partir de outubro; e b) áreas (III, IV, Va e Vb) de pastagem, onde o milho não era cultivado há pelo menos 5 anos. Simultaneamente, realizou-se monitoramento em uma área de Piracicaba/SP, onde o milho era plantado o ano inteiro (área VI). Paralelamente, foram realizadas análises RAPD-PCR para comparação genética de populações desta cigarrinha em Anastácio/MS e de outras quatro localidades do Centro-Sul e Nordeste do Brasil, sendo também avaliados métodos simples de preservação de espécimes de D. maidis para utilização do DNA em análise genética. As coletas com cartões adesivos em Anastácio/MS mostraram que D. maidis coloniza plantios de milho mesmo em áreas de pastagens perenes, onde esse cereal não era cultivado há muitos anos. Picos populacionais simultâneos foram observados na entressafra em todas as áreas estudadas, sendo maiores em locais de solo exposto por aração; assim, o preparo do solo parece exercer influência na escolha da área para o pouso por adultos de D. maidis. Estas informações, aliadas ao fato de que D. maidis não foi capturada em vegetação adjacente aos plantios de milho por vários métodos de amostragem (cartões adesivos, rede de varredura e succionador motorizado), sugerem que os indivíduos colonizadores desses plantios eram imigrantes de locais distantes. A hipótese de migração é reforçada pelas análises de RAPD-PCR que indicaram elevado fluxo gênico entre as populações do Centro-Sul do Brasil. Dos métodos avaliados para preservação do DNA de D. maidis, álcool etílico absoluto ou 70% a -20°C, tampão de extração (inseto macerado e inteiro) e principalmente congelamento a -20°C, mostraram-se os mais adequados. Insetos preservados em álcool etílico absoluto ou 70%, em temperatura ambiente, e insetos secos ao ar mostraram-se imprestáveis para RAPD-PCR após 120, 60 e 10 dias, de armazenamento, respectivamente. Através de bioensaios de transmissão com adultos de D. maidis coletados nos plantios de milho em Anastácio/MS verificaram-se taxas infectividade por S. kunkelii e fitoplasma que variaram de 1,9 a 19,7% e 1,1 a 3,6%, respectivamente, suportando a hipótese de que esses patógenos possam utilizar o vetor para sobrevivência na entressafra e disseminação a longas distâncias. The corn stunt disease, associated with the mollicutes Spiroplasma kunkelii Whitcomb et al. and maize bushy stunt phytoplasma, became very important in Brazil in the 1990’s. As result of changes in the cultural practices in some regions, such as the increase in irrigated areas and the cultivation of a second maize crop in late summer, crop cycles are overlapping in the field, favoring the increase of populations of these pathogens as well as of the leafhopper vector, Dalbulus maidis. ln this research, studies on ecology and population genetics of D. maidis were carried out to better understand its survival mechanism in the corn overseason, in order to improve vector management and disease control. Because maize is the only known host of D. maidis in Brazil, this leafhopper has two possible strategies for survival during corn overseason: migration or dormancy in crop remains or adjacent areas. To investigate these possibilities, populations of D. maidis were monitored biweekly by double-faced yellow sticky cards (7 x 12 cm) for periods that varied from 15 to 29 months, in the region of Anastácio, State of Mato Grosso do Sul (MS). This region is characterized by extensive areas of perennial pastures, where maize is planted in small and isolated areas, with a long overseason period (6-7 months). The survey was accomplished in five areas representing two different situations: a) areas (I and II) where maize is grown once a year in the spring, in the same field plot; and b) areas (III, IV, VA and VB) of pasture where maize had not been cultivated, at least in the previous 5 years. A similar and simultaneous survey was carried out in one area of Piracicaba, State of São Paulo (SP), where is grown year round (area VI). RAPD-PCR analyses were used for genetic comparisons of D. maidis populations in Anastácio/MS (micro region), as well as of populations from distant localities in the center-south (4) and northeast (1) of Brazil (macro region). In addition, a study was carried out to evaluate several methods of preservation of D. maidis specimens for use of its DNA in genetic analysis. The survey with sticky cards in Anastácio/MS showed that D. maidis colonized all maize plantings, even in the isolated areas of pasture where this cereal had not been cultivated before. Simultaneous population peaks were observed in the overseason in all areas studied; the peaks were higher areas where the soil had been exposed by plowing, suggesting that plowed soil might serve as a cue in the choice of the area for landing by adults of D. maidis. These observations, allied to the fact that D. maidis was not captured in vegetation adjacent to the maize plantings after numerous samplings with different methods (yellow sticky cards, sweep net and suction trap), suggest that the leafhoppers that colonized maize plantings in Anastácio/MS were immigrant from distant areas. The migration hypothesis is reinforced by the RAPD-PCR analyses that indicated high gene flow among the populations of the center-south of Brazil. Among methods tested for preservation of DNA of D. maidis, absolute or 70% ethyl alcohol at -20°C, extraction buffer (homogenized or whole insect) and especially freezing at -20°C were the most appropriate. Insects preserved in absolute ethyl alcohol or 70% ethyl at room temperature and air-dried insects were inappropriate for RAPD-PCR after 120, 60 and 10 days of storage, respectively. D. maidis adults collected in the maize plantings of Anastácio/MS showed infectivity rates by S. kunkelii and phytoplasma that varied from 1,9 to 19,7% and 1,1 to 3,6%, respectively, supporting the hypothesis that these pathogens use the vector for survival and long-distance spread in the corn overseason.

Coleoptera order in Brazil presents 105 families with approximately 28,000 species. The life cycle and diversity of Coleoptera are strongly influenced by climate and vegetation. The objective of this study was to evaluate the seasonality and distribution of Coleoptera families in an area of the Cerrado in the Federal District (DF) of Brazil. The insects were collected monthly, between June 2015 and May 2016, using a light trap activated only in nights with a new moon, in an area of cerrado sensu stricto in Planaltina/DF, Brazil. The data were correlated with climatic variables. A total of 21,100 Coleoptera specimens belonging to 34 families were collected, with Melolonthidae (n = 11,075), Carabidae (n = 2,522), Scarabaeidae (n = 2,506), Bostrichidae (n = 1,196), and Chrysomelidae (n = 1,086) being the most abundant. Coleoptera were significantly more abundant in the first half of the rainy season. There was a significant and positive correlation between the abundance of Coleoptera and the climatic variables temperature and precipitation. The data presented in this study are related to an atypical year under the strong influence of the El Niño phenomenon, which may influence the abundance of Coleoptera. Circular analysis revealed that Coleoptera, and the most abundant families, presented seasonality throughout the year with a grouped distribution at the beginning of the rainy season (October to December). This study demonstrates that the richness and abundance of the Coleoptera order, in the Cerrado, is strongly influenced by the characteristic climatic seasons of the biome.

The cassava cultivars BRS 417, BRS 418 and BRS 419 are the first specifically developed for flour and starch production in the Cerrado biome of Central Brazil. They are promising for higher yields, lower production costs (mechanical planting) and the increase of genetic variability in cassava crops.

Two sweet cassava cultivars with pink pulp, BRS 400 and BRS 401, are validated through participatory tests conducted at Distrito Federal, Brazil. Their high root yield stability and their high level of acceptance among producers certainly qualify them as a new crop option for cultivation in the region.

Phyllophaga capillata (Blanchard) and Aegopsis bolboceridus (Thomson) (Coleoptera, Melolonthidae) are important soil pests in soybean and maize crops in central Brazil. The aim of this study was to evaluate the capacity of root consumption by larvae of P. capillata in soybean and A. bolboceridus in maize under controlled conditions and to estimate the damage caused by these species in the field. Root consumption was evaluated in a screened nursery (Brasilia/DF, Brazil). Pots with soybean and maize plants were infested separately with different instars and larval densities (0, 1, 2, 4, 6, 8, and 10 larvae/plant) of P. capillata or A. bolboceridus. After 24 h, the weight, area, and length of the roots were evaluated. Damage estimates were calculated for soybean (Brasilia/DF, Brazil) and maize (Cabeceiras/GO, Brazil) production in fields with and without severe white grub infestations. In the crop production stage of the experiment, we evaluated the number of plants per linear meter, weight of 1000 grains, productivity, number of pods per plant (soybean), and weight and length of ears (maize). For the two species of white grubs, root consumption was relatively low for first-instar larvae, high for second-instar larvae, and especially high for third-instar larvae. The third instars reduced the root system by approximately 25% in soybean and 64% in maize. We observed that P. capillata and A. bolboceridus damaged all evaluated variables, reducing overall soybean productivity by 58.62% and maize productivity by 59.76%. Our results suggest that it is necessary to monitor the presence of these species by sampling and include them in the integrated pest management programs of these crops in the regions where these species occur.

Cetoniidae is a diverse family containing approximately 4,000 species, most of which feed on flowers and fruits. In Brazil, 72 species and 24 genera are recorded. Little is known about this family in the Central region of Brazil, and no research has previously been conducted in the ecologically important Cerrado biome. In this study, we evaluated the diversity and temporal variation of the Cetoniidae in an area of the Cerrado in the Federal District (Brazil) and verified whether the abundance and species richness were influenced by climatic variables. The study was carried out in an area of Cerrado sensu stricto at Agua Limpa Farm in Brasilia/DF. Beetles were collected weekly from October 2013 to September 2014 using 40 traps baited with banana and pineapple fermented with sugarcane juice. A total of 398 specimens comprising 8 genera and 15 species were collected. We observed temporal variation in abundance and richness of the Cetoniidae in direct relation to the climatic characteristics of the Cerrado, with a greater number of individuals and species appearing in the rainy season. Climatic variables such as temperature and humidity appear to have a significant effect on the diversity of Cetoniidae. This is the first study conducted on this family in Central Brazil.

This study aimed to monitor the population fluctuation of Cophes notaticeps (Marshall) (Coleoptera: Curculionidae) in a jatropha (Jatropha curcas L.) plantation in the Federal District, Brazil, through the use of a new trap, combined with different attractive lures and trap colors. The study was conducted at Embrapa Cerrados (Planaltina/DF) in a field trial with 720 plants. The new trap, named CPAC16, was made with PVC pipes (100 mm in diameter) of about 40 cm in length, with a window (8 × 10 cm2) in its center to enable insect access. A lure compartment was fixed on the inside of the trap`s top, and a pot, containing water and detergent, was placed at its bottom to collect the insects. The traps were painted in red, yellow, blue and green. Molasses, ethanol and pineapple were used as attractive lures. The traps were in the field trial area between May 2013 and April 2014 and the insects were collected weekly. The incidence of plants presenting damage caused by C. notaticeps was evaluated in the beginning and at the end of the study. The CPAC16 trap proved efficient in monitoring C. notaticeps. About 3494 of C. notaticeps adults were collected during the study. There were no significant differences among traps painted with different colors. The most attractive lure was molasses collecting 75.2% (n = 2627) of the specimens. Although the population peak occurred in December (n = 1162), C. notaticeps were collected throughout the year. The incidence of plants attacked by C. notaticeps ranged from 66.4% (start) to 100% (end).

The corn leafhopper, Dalbulus maidis (DeLong & Wolcott) (Hemiptera: Cicadellidae), is one of the most important pests of corn, Zea mays L. (Poaceae), in Latin America. We assessed the seasonal and vertical distribution of D. maidis in corn fields in Brazil, in addition to describing the effect of 2 types of yellow traps positioned at 2 heights on the capture of this leafhopper. Sampling was conducted using yellow pan traps and yellow sticky cards throughout the cropping period, in both the rainy and dry seasons. The population of D. maidis in the dry season was much larger than in the rainy season. During both the rainy season and dry seasons, the greatest abundance of D. maidis was observed at 77 d post emergence of the corn, which corresponded to physiological maturity. Greater numbers of insects were captured with yellow cards than with pan traps, at both heights and in both cropping seasons. Also, more insects were captured at the 1.5 m than at the 0.5 m sampling height. The corn leafhopper w...

de Oliveira, E., Magalhaes, P. C., Gomide, R. L., Vasconcelos, C. A., Souza, I. R. P., Oliveira, C. M., Cruz, I., and Schaffert, R. E. 2002. Growth and nutrition of mollicute-infected maize. Plant Dis. 86:945-949. Maize bushy stunt phytoplasma (MBSP) and corn stunt spiroplasma (CSS) diseases are widespread in Brazil. The leafhopper Dalbulus maidis is the insect vector for these pathogenic mollicutes. The effects of these diseases on the development of maize plants and the possible interaction of soil water availability on these effects were evaluated in two experiments carried out on potted plants. Experiment 1 was carried out in a 2 × 4 factorial, where factor 1 corresponded to healthy and mollicute-infected plants and factor 2 to the maintenance of 40, 60, 80, and 100% of the total soil water availability. Leafhoppers collected from a field with high incidence of these diseases were used to inoculate plants with mollicutes. There were three treatments in experiment 2: healthy plants, plants infected with phytoplasma, and plants infected with spiroplasma. MBSP was predominant in experiment 1. The infected plants grew less and lowered nutrient uptake, in distinct proportions, indicating a differential effect of mollicutes on nutrient uptake independent of available soil water. Soil water availability did not significantly affect plant growth and nutrient uptake or mollicute infection. The results indicated that plants infected by mollicutes contained less protein than healthy plants. Experiment 2 showed a reduction in growth of plants infected with mollicutes and less nutrient uptake by spiroplasmainfected plants. The results showed a detrimental effect of the spiroplasma on Mg uptake. Both experiments showed more water retention by infected plants than by healthy ones. These experiments clearly demonstrated that reduced plant growth and nutrient uptake are major effects on plants infected with MBSP and CSS.

The sweet cassava cultivars BRS 396, BRS 397, BRS 398 and BRS 399, were selected through 27 participatory tests conducted at Distrito Federal, Brazil. Their agronomic performance and their high level of acceptance among producers qualify them as a new crop option for cultivation in the region.

No-till sugarcane (Saccharum spp.) systems is considered as an interesting option to reduce the cost of production and allow the conservation of both soil quality and biological activity. This study was conducted at a sugarcane mill in Goiatuba, in the state of Goias, Brazil, which grows sugarcane variety SP 813250. An experiment based on a factorial design (2 × 2 × 2) was set up to compare the diversity of soil arthropods in sugarcane grown under no-till and conventional tillage systems, the efficiency of two methods used to extract soil arthropods (Berlese-Tullgren funnel and flotation in saturated salt solution), and the effects of sampling time (morning or afternoon) at different times of the year (September 2015, November 2015, April 2016, and June 2016). A total of 2776 arthropods belonging to 11 taxa were collected. Acari, Hymenoptera, and Isoptera were the most abundant arthropods (89.3%). The tillage system and sampling time did not affect soil arthropod diversity. The Berlese-Tullgren funnel method was more efficient at extracting arthropods in the rainy season (September and November), whereas the saturated salt solution method was more efficient in the dry season (April and June). The highest soil arthropod abundance was recorded in the rainy season. Our results suggest that the soil disturbance caused by tilling has no effect on soil arthropod diversity in sugarcane plantations.

Phyllophaga capillata (Blanchard) is the most important soil pest in soybean crops in Central Brazil (Federal District and Goiás state). The objective of this work was to study the bio-ecology of P. capillata in the field in the Cerrado of Central Brazil, relating its biology and behaviour to the climatic characteristics of this biome. The study was conducted over three years in a soybean [Glycine max (L.) Merr.] production area (≈6000 ha) in the Federal District. Field samplings were taken to observe the biological stages of P. capillata, preferred oviposition sites and the adult swarming period. Phyllophaga capillata presented an univoltine cycle that lasted about 10 months of egg to inactive adults, and 12 months until the appearance of active adults. Eggs were found in the field in October and November. The larval stage occurred between November and June. Pre-pupae were observed in June and the pupae between July and August. Inactive adults were observed in August and September, and the swarming period was between September and December. Females preferred to oviposit in sites with taller plants. This species synchronises its active phases (larvae and active adults) with soybean cultivation and the rainy season (October/March) in the Brazilian Cerrado. Alternatives for pest management based on their bio-ecological characteristics are presented. Made available in DSpace on 2017-12-05T23:27:39Z (GMT). No. of bitstreams: 1 HowclimateinfluencesthebiologyandbehaviourofPhyllophagacapillata.pdf: 804755 bytes, checksum: ac11bcd09470229697f45352efddee46 (MD5) Previous issue date: 2017-12-05

Este trabalho objetivou estudar a diversidade de macrolepidoptera noturnos em duas fitofisionomias de Cerrado no Distrito Federal (Brasil) e verificar se a separacao entre macrolepidoptera e microlepidoptera concorre para diferencas na sazonalidade e na abundância de cada grupo. O estudo foi realizado nas fitofisionomias cerrado sensu stricto e cerradao na Embrapa Cerrados (Planaltina/DF – Brasil). Foram realizadas coletas quinzenais, entre agosto/2005 e julho/2006, por meio de armadilhas luminosas. Para o estudo da comunidade de macrolepidoptera foram calculados os indices de diversidade (Margalef e Shannon-Wiener), equitabilidade (E), similaridade (Sorensen) e indices faunisticos. Coletou-se 1.034 especimes e 134 morfoespecies de macrolepidoptera, sendo 630 especimes e 89 morfoespecies no Cerrado sensu stricto e 404 especimes e 94 morfoespecies no Cerradao. Os indices de riqueza, diversidade e equitabilidade foram semelhantes entre as duas fitofisionomias. As duas fitofisionomias apresentaram a maioria das morfoespecies de abundância rara, ocorrencia acidental e baixa frequencia. Os macrolepidoptera foram negativamente influenciados pela distribuicao de chuvas e pela umidade relativa do ar. Macrolepidoptera foram mais abundantes na estacao seca e microlepidoptera na estacao chuvosa.

The genetically modified maize to control some caterpillars has been widely used in Brazil. The effect of Bt maize and insecticides was evaluated on the diversity of insects (species richness and abundance), based on the insect community, functional groups and species. This study was conducted in genetically modified maize MON810, which expresses the Cry1Ab protein from Bacillus thuringiensis Berliner, and conventional maize with and without insecticide sprays (lufenuron and lambda-cyhalothrin) under field conditions in Ponta Grossa (Paraná state, Brazil). Insect samplings were performed by using pitfall trap, water tray trap and yellow sticky card. A total of 253,454 insects were collected, distributed among nine orders, 82 families and 241 species. No differences were observed in the insect community based on the richness, diversity and evenness indices. Predators and pollinators were more abundant in genetically modified maize. Parasitoids, detritivores, sap-sucking herbivores and chewing herbivores were more abundant in conventional maize with insecticide sprays. Significant differences were found for the species Colopterus sp., Colaspis occidentalis (L.) and Nusalala tessellata (Gerstaecker) which were most abundant in Bt maize, and Dalbulus maidis and Condylostylus sp.2 in conventional maize. RESUMO: O milho geneticamente modificado visando ao controle de lagartas tem sido amplamente utilizado no Brasil. Em estudo de campo realizado em Ponta Grossa (Paraná, Brasil), compararam-se, com base na diversidade (riqueza de espécies e abundância), os efeitos do milho Bt e do controle químico sobre a comunidade de insetos, grupos funcionais e espécies. A comunidade de insetos foi amostrada no milho geneticamente modificado MON810, que expressa a proteína Cry1Ab de Bacillus thuringiensis Berliner, e no milho convencional com e sem a aplicação de inseticidas (lufenuron e lambda-cialotrina). As amostragens foram realizadas por meio da coleta de insetos utilizando-se armadilha de queda, bandeja-d’água e cartão adesivo. Foram coletados 253.454 insetos, distribuídos em nove ordens, 82 famílias e 241 espécies. Não foram observadas diferenças na comunidade de insetos para os índices de riqueza, diversidade e equitabilidade nos tratamentos avaliados. Predadores e polinizadores foram mais abundantes no milho geneticamente modificado, e parasitoides, decompositores, sugadores e mastigadores, no milho convencional com inseticida. Diferenças significativas foram detectadas para as espécies Colopterus sp., Colaspis occidentalis (L.) e Nusalala tessellata (Gerstaecker), mais abundantes no milho Bt, e Dalbulus maidis e Condylostylus sp.2, mais abundantes no milho convencional.

The symptoms of the main cereal diseases associated with phytoplasma presence such as barley deformation, maize bushy stunt, maize redness, green ear, oat proliferation, oat stunt, oat yellows, rice orange leaf, rice yellow dwarf, triticosecale stunt, wheat blue dwarf and wheat streak, yellowing, and stunting are described. Moreover the phytoplasmas associated with each disease are described together with their geographical distribution. In some cases, factors that affect the occurrence, development, and severity of these diseases are discussed. The insect vectors involved in transmission of some of these diseases are presented, along with the main morphological characteristics adopted for their identification.

The planthopper Poekilloptera phalaenoides (L.) (Hemiptera: Flatidae) is a very common species in various regions of Brazil. The aim of this study was to report on P. phalaenoides biology, its behavior, and host plants in agricultural and natural vegetation areas of the Brazilian Cerrado and to relate the bio-ecology of this species with the climatic characteristics of the biome. The study was conducted between 2005 and 2008 in agricultural areas, and areas covered with typical cerrado sensu stricto and cerradao phytophysiognomies (Planaltina, Federal District, Brazil). Weekly field samples were taken to observe the biological stages of P. phalaenoides. Adult population dynamics were studied using light traps. Host plants were observed in natural vegetation areas. P. phalaenoides presented an 11-mo life cycle (egg to adult). The egg stage, which undergoes diapause, lasted ∼6 mo, and the nymphal stage lasted 7 mo. Adults were most abundantly found in October (64.7%). Specimens of P. phalaenoides w...

The objective of this study was to compare growth and development of Helicoverpa zea Boddie and Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) larvae that were feeding on an artificial diet. Neonate larvae of H. zea and H. armigera were collected in maize fields cultivated at the Brazilian Agricultural Research Corporation, Embrapa Maize & Sorghum, in Sete Lagoas (Minas Gerais) and in farmers' cotton fields in Luís Eduardo Magalhães (Bahia), respectively. Bioassays were conducted in the laboratory using individual larvae in 50 mL plastic cups fed a white bean'based artificial diet and maintained at a temperature of 26 ± 2 °C and a relative humidity of 47 ± 10%. The following larval biological parameters were evaluated: number and duration of instars, survival of larval instars and pupae, larval biomass, larval head capsule size, and larval length. An adaptation index was computed for comparison of development of the 2 species. Significant differences were observed between the species for all variables except for the number of instars and pupal survival. Although H. armigera larvae developed faster and were smaller than H. zea larvae, the diet tested can be considered adequate for rearing both species in the laboratory.

The genus Passiflora L. has more than 400 species, most of which occur natively in tropical and subtropical regions of South America. The fruit of Passiflora tenuifila Killip, one of the native species of Brazil, has great potential for commercial use by pharmaceutical and cosmetic industries, due to its high content of phenolic compounds, which are natural antioxidants. The study was conducted in two areas located in Tocantins and in the Federal District, Brazil. The presence of globose lumps and thickening of the stems on plants of Pa. tenuifila was observed on plants in these areas. Injured samples taken from both locations were analyzed and showed the presence of larvae and pupae of a Curculionidae, which completed their life cycle in the laboratory. The adults were identified as Philonis crucifer (Brethes) (Coleoptera: Curculionidae). In Tocantins, 100% of the plants in the trial area were infested, while in the Federal District trial the incidence of infestation was 20.3%. This is the first report of an insect on Pa. tenuifila, indicating the need to develop management strategies for this pest to be applied in commercial crops of this Passiflora species.

The third-instar larvae and pupae of Aegopsis curvicornis Burmeister, and A. bolboceridus (Thomson) are described for the first time based on specimens collected and reared in Cundinamarca, Colombia and Planaltina, DF, Brazil, respectively. A key to the known thirdinstar larvae of the Agaocephalini is provided. Some data on the biology of both species are also included.