To take the students attention in physics lectures is always a challenge. The projectile motion is not an exception. Then, study of popcorn motion can be a way to introduce and motivate the students in this subject. In this work, the popcorn flight, caused by the popping process was recorded by a cellular phone and analyzed frame by frame. Then, the drag coefficient (CD) of vertically moving popcorns is determined and its dependency with the vertical velocity (vy) and with the Reynolds number (Re) is explored. Our results show that CD increases exponentially when vy decreases. Also, CD shows higher uncertainties when the popcorn is close to its maximum vertical trajectory. The dependency of CD with Re shows that the popcorn flights are governed, mainly, by a laminar flow motion (Re ＜ 2000). challenge exception Then subject work flight (CD (vy explored decreases Also trajectory governed mainly 2000. 2000 . 2000) 200 20 2

ABSTRACT. Popcorn (Zea mays L. everta) is a specialty crop with a higher aggregate economic value than that of common maize. In Brazil, national literature is still incipient and contradictory in terms of plant population management and water requirements. Furthermore, the interaction between these factors has not been reported, despite the increasing cultivation of popcorn. The objective of this trial was to determine whether agricultural traits and popping expansion from hybrid IAC 125 could be affected by plant density and levels of irrigation water, in addition to determining the significance level of the interaction between both factors. We investigated five plant populations (40,000, 55,000, 70,000, 85,000, and 100,000 plants ha-1) and five different levels of water depth in 2014/2015 [574.86 (without supplementary irrigation), 609.86, 644.86, 679.86 (control), and 714.86 mm] and 2015/2016 [857.4 (without supplementary irrigation), 867.26, 886.60, 916.78 (control), and 959.81 mm] using a complete block design with split-plot, comprising a main plot (for plant populations) and subplot (for water depth), with six replicates for each set. We found increasing linear effects from grain yield under population density and levels of water depth, but this interaction was not significant. Moreover, the popping expansion for the main effects and the interaction between plant populations and water depth, were not significant. ABSTRACT Zea L everta maize Brazil requirements Furthermore reported popcorn 12 40,000, 40000 40 000 (40,000 55000 55 55,000 70000 70 70,000 85000 85 85,000 100000 100 100,00 ha1 ha 1 ha-1 20142015 2014 2015 2014/201 574.86 57486 574 86 [574.8 without irrigation, , irrigation) 60986 609 609.86 64486 644 644.86 67986 679 679.8 control, control (control) 71486 714 714.8 mm 20152016 2016 2015/201 857.4 8574 857 4 [857. 86726 867 26 867.26 88660 886 60 886.60 91678 916 78 916.7 95981 959 81 959.8 splitplot, splitplot split plot, split-plot depth) set significant Moreover 40,000 4000 00 (40,00 5500 5 55,00 7000 7 70,00 8500 8 85,00 10000 10 100,0 ha- 2014201 201 2014/20 574.8 5748 57 [574. 6098 609.8 6448 64 644.8 6798 67 679. (control 7148 71 714. 2015201 2015/20 857. [857 8672 2 867.2 8866 88 6 886.6 9167 91 916. 9598 95 959. 40,00 400 0 (40,0 550 55,0 700 70,0 850 85,0 1000 100, 201420 20 2014/2 574. [574 609. 644. 201520 2015/2 [85 867. 886. 9 40,0 (40, 55, 70, 85, 20142 2014/ [57 20152 2015/ [8 40, (40 [5 [ (4 (

ABSTRACT. The Spodoptera frugiperda, is one of the most deleterious pests of popcorn and the identification of resistant genotypes is determinant in breeding programs. The objective of this study was to select popcorn genotypes resistant to S. frugiperda and the key traits related to the identification of resistance. The popcorn varieties UEM J1, Composto Márcia, Arachida, Composto Gaúcho, and Zapalote Chico (resistant check) were evaluated in a completely randomized design with 100 replications. The experimental unit consisted of one Petri dish, containing plant material and a caterpillar The following traits were evaluated: larval stage duration (LSt), food intake weight(IW), final larva weight (FW), mean larva weight (MW), feces (F), assimilated (A) and metabolized food weight (M), relative consumption rate (RCR), relative metabolic rate (RMR), relative growth rate (RGR), conversion efficiency of ingested food (CEI), apparent digestibility (AD), conversion efficiency of digested food (CED), and leaf area consumed (LAC). The diagnosis of multicollinearity, analysis of canonical variables, genetic divergence, hierarchical clustering, factor analysis and canonical correspondence analysis were carried out to perform multivariate analysis. After the multicollinearity test, the traits FW, IW, RCR, AD, and LAC were maintained for further analysis. The traits IW, FW and AD were determinant in the resistance by antixenosis expressed by the varieties Zapalote Chico and Arachida, for the varieties Composto Gaúcho and Composto Márcia the determining characteristics were RCR and LAC and for the variety UEM J1 the variable LAC showed greater importance. Variety Arachida was considered resistant to S. frugiperda by antixenosis and can be used in the future as a source of favorable alleles to breed resistant popcorn hybrids. The traits relative consumption rate, apparent digestibility and leaf area consumed were considered key traits in the identification of resistance against S. frugiperda in popcorn genotypes. ABSTRACT programs S J check 10 replications dish LSt, LSt , (LSt) weightIW, weightIW IW weight(IW) (FW) MW, MW (MW) F, F (F) A (A M, M (M) (RCR) RMR, RMR (RMR) RGR, RGR (RGR) CEI, CEI (CEI) (AD) CED, CED (CED) LAC. . (LAC) variables divergence clustering test importance hybrids 1 (LSt weight(IW (FW (MW (F (M (RCR (RMR (RGR (CEI (AD (CED (LAC

Resumo Mancha-de-Bipolaris é uma das mais importantes doenças foliares do milho. Estratégias de manejo adequadas e o uso de cultivar resistente permitem o controle da doença, mas para tanto, conhecer os aspectos associados ao patógeno e a resposta do hospedeiro é necessário para traçar estratégias eficientes para seleção de genótipos resistentes a essa doença. Neste sentido, objetivou-se realizar a caracterização do isolado de Bipolaris maydis avaliando a patogenicidade em diferentes linhagens de milho-pipoca e os sintomas gerados no hospedeiro a partir da inoculação. A caracterização do isolado consistiu na avaliação macromorfológica das colônias e micromofológica dos conídios em meio nutritivo BDA. Para avaliação da patogenicidade do isolado foi conduzido um experimento em casa de vegetação utilizando 20 linhagens endogâmicas de milho-pipoca, com delineamento em blocos casualizados, com quatro repetições. A inoculação foi realizada por meio de pulverização em folhas, com uma suspensão contendo 1,0 x 104 conídios.ml-1 do isolado CF/UENF 501 de B. maydis. Foi realizada uma avaliação de incidência e três avaliações de severidade dos sintomas da doença, com o intervalo de sete dias para cada avaliação. Os dados da caracterização morfológica do isolado foram analisados por meio da estatística descritiva e para severidade da doença foi aplicado o modelo de regressão linear de primeiro grau. Realizou-se a análise de variância para o coeficiente linear e angular obtido para cada tratamento e quando constatada diferença aplicou-se o agrupamento de médias de Scott-knott a 5% de significância. O isolado apresentou colônias com coloração cinza esverdeado, aspecto algodonoso e forma irregular. As linhagens L353 e L354 e L624 estão entre as linhagens que apresentaram maior resistência no inicio e ao longo das avaliações. A elevada virulência do isolado CF/UENF 501 possibilitou diferenciar as linhagens quanto a intensidade da doença, bem como o padrão dos sintomas apresentados.

Abstract Southern corn leaf blight (SCLB) is one of the most important corn leaf diseases. Appropriate management strategies and the use of resistant cultivars allow disease control. Therefore, knowing the aspects related to the pathogen and the response of hosts makes it possible to design efficient strategies for selecting genotypes resistant to this disease. In this sense, the objective was to carry out the Bipolaris maydis isolate characterization, evaluating the pathogenicity in different popcorn lines and the symptoms generated in the host after inoculation. The isolate characterization consisted of the macromorphological evaluation of the colonies and the micromorphological evaluation of the conidia in the PDA medium. An experiment was carried out in a greenhouse to evaluate the pathogenicity of the isolate, using 20 inbred lines of popcorn in a randomized block design with four replicates. Inoculation was carried out by spraying leaves, with a suspension containing 1.0 x 104 conidia.ml-1 of the CF/UENF 501 isolate of B. maydis. An incidence assessment and three assessments of disease symptom severity were performed, with seven days intervals between evaluations. The morphological characterization data of the isolate were analyzed using descriptive statistics, and for disease severity, the linear regression model was applied the first-degree model. The variance analysis was performed for the linear and angular coefficients obtained for each treatment. When a difference was found, the Scott-Knott clustering algorithm at 5% significance was applied. The isolate had gray-green colonies, a cottony appearance, and an irregular shape. The lines L353, L354, and L624 show more resistance at the beginning and throughout the evaluations. The high virulence of the CF/UENF 501 isolate made it possible to differentiate the lines in terms of disease intensity and the pattern of symptoms presented.

ABSTRACT Introduction: Thulium Fiber Laser (TFL) is the most modern technology to treat nephrolithiasis and ureterolithiasis in endourology. Although there are a lot of new studies coming up, we still don't have data on how this laser works in some rare diseases. Cystinuria is the most common genetic nephrolithiasis disorder (1), known for its recurrent lithiasis (2). Our main goal in this video is to show a successful case of cystine calculi treated with Thulium Fiber Laser (Laser Fiber Dust/Quanta System™). Cystinuria is the most common genetic nephrolithiasis disorder (1), known for its recurrent lithiasis (2). Materials and Methods: A 25 years-old male, cystinuric, presented with a CT scan, showing a 10mm stone on the right side and two calculi 6 and 7 mm on the left side, all located in the lower calyx. Bilateral flexible ureteroscopy was done using a reusable digital flexible ureteroscope. Starting on the left side, we repositioned the stone from the lower to the upper calyx, using a tipless front opening basket. Lithotripsy was performed using TFL. Settings were 100 Hz (frequency) and 100 mJ (energy) for dusting. Popcorn technique was also used, setting the laser at 100Hz and 200 mJ, obtaining good dusting. On the right side, lithotripsy was performed in the inferior calyx, also resulting in “snowstorm”. Procedure time was 120 minutes. Results: The postoperative was uneventful. Follow up CT showed a 3 mm residual fragment in the right kidney. Conclusion: This video demonstrates the treatment of bilateral cystine calculi with Thulium Fiber Laser. Reasonable procedure time and excellent dusting results are encouraging, pointing towards great improvements in endourology. Introduction TFL (TFL endourology dont don t diseases 1, 1 , (1) 2. 2 . (2) DustQuanta Dust Quanta System™. System System™ System™) Methods yearsold years old male cystinuric scan calyx ureteroscope basket 10 frequency (frequency energy (energy used 20 snowstorm. snowstorm “snowstorm” 12 minutes Results uneventful kidney Conclusion encouraging (1 (2 “snowstorm (

Abstract Morphological and phenological variability of Guaraní maize germplasm from Northeastern Argentina (NEA) are potential sources of genetic resources, constituting valuable repositories of alleles associated with tolerance and resistance to biotic and abiotic stresses. Here, we studied the morphological and phenological variability in maize populations of 14 Guaraní landraces from NEA and analysed the relationship among them. These landraces were characterised according to the endosperm consistency of grain as Popcorn (Pc), Floury (F) and Floury with corneal periphery (F-Pc). There were inter-population differences in phenological characters as time from germination to tassel emergence, from germination to spike emergence and from germination to anthesis (length of vegetative cycle -LVC). The morphological and phenological data here reported were used to carry out a cluster analysis, in which the F and Pc populations appeared as two separate groups and the F-Pc populations were included in the F group. Thus, the well-defined F (including F-Pc) and Pc genetic pools should be prioritised within the framework of breeding plans as well as ex situ and in situ conservation programs. For these purposes it is essential the morphological, phenological and genetic characterisation the maize Guaraní landraces. (NEA resources stresses Here 1 them Pc, , (Pc) (F FPc. FPc . (F-Pc) interpopulation inter population length LVC. LVC -LVC) analysis group Thus welldefined defined including programs (Pc (F-Pc -LVC

Resumen Las razas de maíz Guaraní, nativas del noreste de Argentina (NEA), son fuentes potenciales de recursos genéticos y constituyen depósitos valiosos de alelos asociados con tolerancias y resistencia a estreses bióticos y abióticos. En este trabajo, estudiamos la variabilidad morfológica y fenológica en poblaciones de 14 razas guaraníes de maíz del NEA y analizamos las relaciones entre ellas. Estas razas se caracterizaron según la consistencia del endosperma de sus granos como Popcorn (Pc), Floury (F) y Floury con periferia cornea (F-Pc). Se observaron diferencias interpoblacionales en caracteres fenológicos como el tiempo desde la germinación hasta la emergencia de la panoja, desde la germinación hasta la emergencia de la espiga y desde la germinación hasta la antesis (longitud del ciclo vegetativo-LVC). Los datos morfológicos y fenológicos reportados aquí se emplearon en un análisis de conglomerados, en el cual las poblaciones F y Pc formaron dos grupos separados, mientras que las poblaciones F-Pc se incluyeron en el grupo F. Por lo tanto, los pooles génicos bien definidos F (incluyendo F-Pc) y Pc deben priorizarse en el marco de planes de mejoramiento y programas de conservación ex situ e in situ. Para estos propósitos es esencial la caracterización morfológica, fenológica y genética de las razas nativas de maíz Guaraní. Guaraní NEA, , (NEA) abióticos trabajo 1 ellas Pc, (Pc) (F FPc. FPc . (F-Pc) panoja longitud vegetativoLVC. vegetativoLVC vegetativo LVC vegetativo-LVC) conglomerados separados tanto incluyendo (NEA (Pc (F-Pc vegetativo-LVC

Abstract The hybrids are responsive to phosphorus application, have high use efficiency and can produce high mean yields in environments with low and high phosphorus. The mean PE of these hybrids is high, therefore they are recommended for cultivation in the North and Northwest regions of Rio de Janeiro State, Brazil. application State Brazil

Abstract The hybrids UENF N01, N02 and N03 have enhanced nitrogen-use efficiency, particularly in terms of N responsiveness, which makes them ideal for low-input cultivation. Even under abiotic stress, popping expansion is not reduced, indicating these hybrids for growth in the N and NW of Rio de Janeiro State. N01 N0 nitrogenuse nitrogen use efficiency responsiveness lowinput low input cultivation stress reduced State

ABSTRACT Large amounts of nitrogen (N) fertilizers applied to maize cropping systems support high yields but cause adverse environmental impacts. The development of cultivars with higher N use efficiency is essential to maintain sustainable production. Thus, the present study aimed to select popcorn inbred lines efficient and responsive to N fertilization expressing high popping expansion. Fifty-one popcorn inbred lines from different origins were evaluated in the field under low and high N availability, arranged in a randomized complete block design with three replications. The two main traits of economic interest in the crop were evaluated: grain yield (GY) and popping expansion (PE). A joint analysis of variance was performed and a scatter plot was generated to classify the inbred lines regarding the response to the N use, focusing on GY. For PE, a Scott-Knott grouping of means was conducted. Within the panel of evaluated popcorn inbred lines, it was possible to identify sources of favorable alleles for nitrogen use efficiency and popcorn expansion, highlighting the inbred lines L205, L206, L217, and L395. These genotypes emerge as potential parents to be included in mating blocks for the development of hybrids and/or breeding populations with high nitrogen use efficiency and popping expansion. (N impacts production Thus Fiftyone Fifty one availability replications GY (GY PE. PE . (PE) ScottKnott Scott Knott conducted L205 L L206 L217 L395 andor or (PE L20 L21 L39 L2 L3

Abstract Pinole is a fine flour made from popped and toasted maize and it is the predominant food in the Rarámuri diet. This work aims to advance the sensory mapping of pinole from Sierra Tarahumara and evaluate its aroma. Three samples of pinole were analysed using a modified flash profile, Head Space-Solid Phase Dynamic Extraction coupled to Gas Chromatography-Mass Spectrometry, and electronic nose (e-nose). The e-nose analysis showed few significant differences between the pinoles. The results of the sensory profile showed that the descriptive characteristics (seventeen attributes in total) could discriminate each sample, and this could be a consequence of the slight differences in the traditional processes applied. Forty-nine volatile compounds were identified in the three samples, of which twenty-two had previously been identified in popcorn and other corn products. A Multiple Factor Analysis showed correlations of various volatile compounds (e.g., heterocyclic compounds probably formed during roasting and smoking) and sensor responses with sensory odour attributes such as peanut, corn, toasted, sweet and pinole as well as flavour attributes like toasted, pinole, sweet and corn taste.

Resumen El pinole es una harina fina hecha con base en maíz reventado, tostado y es el alimento predominante en la dieta Rarámuri. Este trabajo tiene como objetivo avanzar en el mapeo sensorial del pinole de la Sierra Tarahumara de Chihuahua, México y evaluar su aroma. Se analizaron tres muestras del producto utilizando el Perfil Flash modificado, la cromatografía de gases-la espectrometría de masas con extracción dinámica en la fase sólida de espacio de cabeza (HS-SPDE) y la nariz electrónica (e-nose). En el análisis de la nariz electrónica hubo pocas diferencias significativas entre los pinoles. En los resultados del perfil sensorial las características descriptivas (diecisiete atributos en total) discriminaron cada muestra, como una consecuencia de las ligeras diferencias en los procesos tradicionales aplicados. Se identificaron cuarenta y nueve compuestos volátiles en las tres muestras, de los que veintidós se habían determinado previamente en las palomitas de maíz y en otros productos de maíz. El Análisis Factorial Múltiple mostró correlaciones de varios compuestos volátiles (p. ej., los compuestos heterocíclicos formados durante el tostado y el ahumado) y las respuestas de los sensores con dos tipos de atributos: de olores sensoriales como maní, maíz, tostado, dulce y pinole, y los de sabor como tostado, pinole, dulce y maíz.

Resumen En el proceso de fertilización genética del maíz (Zea mays L.), el polen ejerce un efecto directo e inmediato sobre las propiedades de la cariópside conocido como Xenia. Esta situación reviste gran importancia en maíz palomero, pues la capacidad de reventado depende de las características del endospermo, por lo que es necesario estudiar la magnitud de la Xenia en maíces palomeros, para emitir recomendaciones para la producción y la conservación. En el presente estudio se llevó a cabo en 2018, se evaluó el efecto de Xenia de variedades de maíz de diferente constitución de endospermo, sobre características físicas y de reventado del cariópside. El experimento se realizó en dos localidades, Montecillo, Estado de México y Santa María Zacatepec, municipio de Juan C. Bonilla, Puebla, utilizando un diseño experimental de bloques completos al azar. Como progenitores hembra se utilizaron las variedades de maíz palomero Compuesto Amarillo y North American Yellow Pearl Popcorn, mientras que como progenitores macho se emplearon los mismos materiales, CML-349 de endospermo semi-cristalino y una población de la raza Cacahuacintle de endospermo harinoso. Los resultados mostraron que el Compuesto Amarillo presentó una disminución de las dimensiones de la cariópside de 0.17 a 13%, mientras que en NAYPP el efecto resultó en incremento de 2.27 a 18%. El volumen de reventado presentó el mayor efecto de Xenia, ya que en el Compuesto Amarillo éste disminuyó de 25 a 49% cuando se polinizó con los maíces no palomeros, mientras que en NAYPP la disminución fue de 59%. Con los resultados, existió efecto de Xenia en el maíz palomero evaluado, el cual fue mayor sobre el volumen de expansión, mientras que en las características físicas del cariópside este efecto fue menos acentuado.

Abstract In the process of genetic fertilization of corn (Zea mays L.), pollen exerts a direct and immediate effect on the properties of the resulting caryopsis known as Xenia. This situation is of great importance in popcorn, since the popping capacity depends directly on the characteristics of the endosperm, so it is necessary to study the magnitude of Xenia in popcorns to give appropriate recommendations for the production and conservation of this genetic resource. The present study was carried out in 2018, the effect of Xenia of corn varieties of different endosperm constitution was evaluated on physical and popping characteristics of the caryopsis of two genotypes of popcorn. The experiment was conducted in two localities, Montecillo, State of Mexico and Santa María Zacatepec, municipality of Juan C. Bonilla, Puebla, using a randomized complete block experimental design. The varieties of popcorn Compuesto Amarillo and North American Yellow Pearl Popcorn were used as female parents, while the same materials, CML-349 of semicrystalline endosperm and a population of the Cacahuacintle race of mealy endosperm were used as male parents. The results showed that Compuesto Amarillo had a decrease in the dimensions of the caryopsis from 0.17 to 13%, while in NAYPP, the effect resulted in an increase, from 2.27 to 18%. The popping volume showed the greatest effect of Xenia, since in Compuesto Amarillo, it decreased from 25 to 49% when pollinated with non-popcorns, while in NAYPP the decrease was 59%. According to the results, there was an effect of Xenia on the popcorn evaluated, which was greater on the volume of expansion, while in the physical characteristics of the caryopsis, this effect was less pronounced.

Resumen Un enfoque novedoso para fortalecer las estrategias de mejoramiento genético de maíz es el uso del índice de estabilidad de múltiples caracteres (MTSI), este índice permite identificar genotipos más estables y de alto rendimiento con mayor confiabilidad que los métodos anteriores. Con el objetivo de seleccionar líneas S1 sobresalientes de maíz morado reventón basado en el MTSI, 80 líneas S1 de maíz morado reventón fueron evaluados en tres ambientes. Se estudiaron 11 características: volumen de expansión (VE), pericarpio pigmentado (PP), rendimiento de grano (GY), porcentaje de expansión (PE), floración masculina (FM) longitud de mazorca (LM), humedad del grano (HG), altura de planta (AP), peso de 100 granos (PG), volumen de 100 granos (VG) y tamaño del grano expandido (TG). Los resultados indicaron que las diferencias ambientales contribuyeron en mayor medida a la variación total, seguido de las diferencias genotípicas, ambos fueron significativas para todas las variables, además, la interacción genotipo x ambiente fue significativa en 10 de 11 características evaluadas. De acuerdo con el MTSI y con una presión de selección del 15%, 12 líneas S1 de maíz morado reventón fueron seleccionados como las más estables y de alto rendimiento entre los 80 genotipos evaluados. Las líneas S1 seleccionadas serán convertidas en líneas dobles haploides y evaluadas por sus habilidades combinatorias general y específica, así mismo, se determinará la capacidad antioxidante que no se conoce.

Abstract A novel approach to strengthen maize breeding strategies is the use of the multi-trait stability index (MTSI), this index allows the identification of more stable and high-yielding genotypes with greater reliability than previous methods. To select outstanding purple popcorn S1 lines based on the MTSI, 80 purple popcorn S1 lines were evaluated in three environments. 11 characteristics were studied: expansion volume (VE), pigmented pericarp (PP), grain yield (GY), expansion percentage (PE), male flowering (FM), ear length (LM), grain moisture (HG), plant height (AP), weight of 100 grains (PG), volume of 100 grains (VG) and expanded grain size (TG). The results indicated that the environmental differences contributed to a greater extent to the total variation, followed by the genotypic differences, both were significant for all the variables, in addition, the genotype x environment interaction was significant in 10 of 11 characteristics evaluated. According to the MTSI and with a selection pressure of 15%, 12 purple popcorn S1 lines were selected as the most stable and high yielding among the 80 genotypes evaluated. The selected S1 lines will be converted into double haploid lines and evaluated for their general and specific combinatorial abilities, likewise, the unknown antioxidant capacity will be determined.

ABSTRACT. The cultivation of special corns, such as baby corn, has had a positive influence on the economy of the country. Despite its importance, there is still a need for studies aimed at increasing production and planting areas of the crop. Phytosanitary studies are of particular interest, as the cultivation of such crops is susceptible to a series of pathogens, such as Bipolaris maydis, Exserohilum turcicum, and Puccinia polysora. The use of resistant cultivars is the most effective way to prevent the occurrence of these diseases. Thus, the present study aimed to identify popcorn lines that have the potential for baby corn production and are resistant to the main leaf diseases that affect the crop. The experiment was conducted in randomized blocks with four replications of 30 lines in each area, during two planting seasons. The area was located at the Federal Institute of Espírito Santo (IFES) Campus of Alegre, situated in Rive district, Espírito Santo State, Brazil. Using the obtained data, the area under the disease progress curve was obtained. Subsequently, analysis of the joint variance of the data was conducted, and when a significant effect was found, a grouping of means test was conducted. The Mahalanobis distance for each pair of lines was also calculated, and the genetic distance matrix was used to construct a dendrogram using the UPGMA method. Considering the averages obtained for the three diseases (Southern corn leaf blight, Northern corn leaf blight, and Southern rust), lines L61, L63, L65, L683, L684, L685, L691, L694, and L695 were identified as possible donors of resistance alleles for multiple diseases. Multivariate analysis efficiently grouped the lines L61, L63, L684, L685, and L691, which are described as most resistant in the univariate analysis.

RESUMO O milho pipoca é uma importante cultura agrícola, consumida como petisco pela população mundial. No Brasil, a falta de cultivares com alto potencial de rendimento de grãos e elevado volume de expansão é considerada uma das principais dificuldades. Nesse contexto, o presente trabalho teve como objetivo avaliar a divergência genética entre linhagens elite de milho pipoca por meio de marcadores AFLP (Amplified Fragment Length Polymorphism), estimar a capacidade geral e específica de combinação (GCA e SCA, respectivamente) e correlacionar a distância genética com a SCA e a média dos híbridos. Para o estudo de divergência genética, foram avaliadas 45 linhagens de milho pipoca provenientes de diferentes híbridos e variedades. Posteriormente, dez linhagens foram selecionadas para análise dialélica; o rendimento de grãos (GY) e a capacidade de expansão (PE) foram avaliados em três ambientes. Com base nos marcadores AFLP, foi observada uma ampla variabilidade entre as linhagens avaliadas. Na avaliação dos híbridos, foi observado efeito significativo para GY e PE, sendo que alguns híbridos apresentaram alto potencial de GY e PE quando comparados às testemunhas comerciais. Por meio da análise dialélica, foi observado efeito significativo da GCA para GY e PE, indicando que as linhagens diferem na frequência de alelos favoráveis, com linhagens promissoras para a formação de híbridos ou variedades sintéticas. Por outro lado, para SCA, nenhum efeito significativo foi observado para essas características. A distância genética não se correlacionou com GY e Ŝij, demonstrando ausência de consistência na predição de grupos heteróticos para milho pipoca via marcadores AFLP.

ABSTRACT Popcorn is an important agricultural crop that is consumed as a snack food worldwide. In Brazil, the lack of cultivars with high potential grain yield and popping expansion volume is a vital problem. Therefore, the present study aimed to evaluate the genetic divergence among elite popcorn lines using amplified fragment length polymorphism (AFLP) markers to estimate the general and specific combining ability (GCA and SCA, respectively), and correlate the genetic distance with the SCA and hybrid means. For the genetic divergence study, 45 popcorn inbred lines of different hybrids and varieties were evaluated. Subsequently, 10 inbred lines were selected for diallel analysis; grain yield (GY) and popping expansion (PE) were evaluated in three environments. A wide variability of popcorn inbred lines was observed based on the AFLP markers. After evaluating the hybrids, a significant effect was observed for GY and PE, with some experimental hybrids with higher potential GY and PE than the commercial cultivars. From the diallel analysis, a significant effect was observed for GCA for GY and PE; therefore, the lines differed in the frequency of favorable alleles, with promising inbred lines for forming hybrids or synthetic varieties. However, for SCA, no significant effect was observed for these traits. Genetic distance did not correlate with GY and Ŝij, demonstrating an absence of consistency in the prediction of heterotic groups for popcorn using AFLP markers.

ABSTRACT The development of new popcorn cultivars that include wide adaptation, high stability and superior performance characteristics is one of the main alternatives to mitigate the effects of the genotype × environment interaction. In this sense, our main goal was to evaluate the adaptability and stability of new popcorn hybrids using Bayesian additive main effects and multiplicative interaction (BAMMI) method for grain yield (GY) and popping expansion capacity (PE) traits. We evaluated GY and PE from 45 new popcorn hybrids and three commercial cultivars (IAC–125, Pop Top and Top Ten) as checks in six different environments. Genotype × environment interaction, correlation and stability analyses were performed using Bayesian approaches. The full models tested presented the lowest deviance information criterion (DIC) values when compared to null models, indicating the presence of the genotype × environment interaction for both evaluated agronomic traits. Negative correlations were observed between GY and PE (r = –0.24, 95% highest posterior density [HPD] = –0.31; –0.17) and confirm the difficulty to perform selection simultaneously for both characteristics. UEM–3 and UEM–7 hybrids showed wide stability and high a posteriori averages for GY and PE. Both cultivars can be registered and recommended for cultivation in popcorn producing regions.