ABSTRACT The search for more sustainable systems of rice cultivation, especially in relation to water use, has included the evaluation of more-efficient irrigation systems in addition to alternative water sources. The aim of this study was to conduct a phytosociological survey of weeds in rice crops irrigated by subsurface drip with different concentrations of treated dairy effluent, maintaining the soil moisture at saturation or field capacity. A pilot scale experiment was carried out in a protected environment using a randomised block design in a 5 x 2 factorial scheme, with four replications. The IAC 301 cultivar (Arborio rice) was chosen. The phytosociological surveys were carried out on four different dates, and considered the composition as well as the distribution of plant species in each of the applied treatments, using the importance value index (IVI) to evaluate the influence of each treatment. The results showed that cultivating irrigated rice, giving priority to water management, altered the ecology of invasive plants. Fourteen weed species were identified, distributed over 10 families. The effluent dose did not alter the incidence of invasive plants, and only at the final evaluation was there a reduction in the IVI value at effluent concentrations of 50% and 75%. For soil moisture, the highest IVI values occurred on the first two days of the survey under saturated conditions; this result was reversed closer to plant maturity, when the IVI values were higher at field capacity. cultivation use moreefficient efficient sources capacity scheme replications 30 Arborio chosen dates treatments (IVI treatment management plants identified 1 families 50 75 75% conditions maturity 3 7

Summary: Bioremediation with humic substances is one of the recent and promising techniques for the restoration of soils contaminated by hydrocarbons, but little information is available on its behavior in different types of soil. For these reasons, this research aimed to evaluate the removal of total petroleum hydrocarbons (HTP) in three types of soil with different textures (S1, S2 and S3) and treated with organic vermicompost amendments (cocoa husks, Theobroma cacao; rice, Oriza sativa; sugarcane bagasse, Saccharum officinarum; cow manure) and commercial humic substances (potassium humate). A randomized multifactorial experimental design (3 × 3 × 2) was proposed, which consisted of the type of soil, organic amendment (without vermicompost, with organic vermicompost, commercial humic substances) and microbial load (with microorganisms, without microorganisms). The results were analyzed using the ANOVA-Tukey tests in the Statgraphics CenturionTM V.18 program (α = 0.05) in order to evaluate significant differences between treatments. The results show that S2 with the addition of organic matter had the highest removal (86% of HTP) after 60 days of incubation, compared to the treatment with commercial humic substances, which are related to the low bioavailability of the microorganisms. This behavior was also observed in S3 with a TPH percentage removal of 77.52 and 63.4% for S1. Finally, the cell growth rate was better in S2 with commercial humic substances. An average growth of 94 × 104 CFU g-1 of soil was obtained during the 60 days of evaluation of the experiment, and a maximum of 98×105 CFU g-1 of soil in the 45 days of treatment. To conclude, the use of vermicompost is adequate for clayey soils, since the degradation rates are higher in them. In addition, they represent a cheaper alternative to synthetic treatments and revaluation of organic waste.

Resumen: La biorremediación utilizando sustancias húmicas es una de las técnicas recientes y prometedoras para la restauración de suelos contaminados por hidrocarburos, pero existe poca información sobre su comportamiento en los diversos tipos de suelo. Por estas razones, esta investigación tuvo como objetivo evaluar la remoción de hidrocarburos totales del petróleo o HTP en tres suelos con diferentes texturas (S1, S2 y S3) y tratados con enmiendas orgánicas de vermicomposta (cascarillas de cacao, Theobroma cacao; arroz, Oriza sativa; bagazo de caña, Saccharum officinarum; estiércol de vaca) y sustancias húmicas comerciales (humato de potasio). Se planteó un diseño experimental multifactorial aleatorio (3 × 3 × 2), constituido por tipo de suelo, enmienda orgánica (sin vermicomposta, con vermicomposta orgánica, con sustancias húmicas comerciales), y carga microbiana (con microorganismos, sin microorganismos). Los resultados fueron analizados mediante las pruebas ANOVA-Tukey en el programa Statgraphics Centurion TM V.18 (α = 0.05) con el fin de evaluar diferencias significativas entre los tratamientos. Los resultados muestran que S2 con vermicomposta orgánica tuvo la mayor remoción (86% de HTP) luego de 60 días de incubación, en comparación con el tratamiento con sustancias húmicas comerciales, relacionándose con la baja biodisponibilidad de microorganismos. Este comportamiento también se observó en S3, el cual tuvo un porcentaje de remoción de HTP de 77.52 y 63.4%. Finalmente, la tasa de crecimiento celular fue mejor en S2 con sustancias húmicas comerciales. Se obtuvo un crecimiento promedio de 94×104 UFC g-1 de suelo durante los 60 días de evaluación del experimento, y un máximo de 98×105 UFC g-1 de suelo a los 45 días de tratamiento. Se concluye que el uso de vermicomposta es adecuada para suelos arcillosos, ya que las tasas de degradación son mayores en ellos. Además, representan una alternativa de menor costo que los tratamientos sintéticos y de revalorización de residuos orgánicos.

Abstract In Mexico, it has been a challenge to meet the national demand for rice, which exceeds 850 000 tons per year, so in recent years imports have been resorted to. Given this, in order to counteract this situation, the development of technologies specific to production systems and the implementation of genetic improvement programs aimed at the generation of genotypes and their adaptation to the rice-growing areas of the country have been encouraged. Despite the efforts, there is still a lack of long and thin grain rice varieties that are of good industrial grain quality and competitive with imported rice, in addition to being preferred by the consumer. Consequently, in the rice-growing region of Michoacán, advanced rice lines were identified, where the Lombardía FLAR 13 genotype emerged. During the 2017 to 2020 cycles, this material was experimentally evaluated in comparison with the Milagro Filipino genotype in Lombardía, municipality of Gabriel Zamora, Michoacán. Morphological and productive variables were recorded. With the data obtained, in addition to the verification of the tests of normality and homogeneity of variances, they were analyzed with the t-student statistical test for independent samples. The results showed superiority of the Lombardía FLAR 13 genotype over the Milagro Filipino genotype, since in most of the morphological variables evaluated, it equaled and even exceeded in the productive variables, particularly in the latter, the yields were greater than 9 t ha-1, it also showed productive stability during the evaluated cycles, so it is competitive with the conventional variety Milagro Filipino, which is established in the area.

Resumen En México, ha sido un reto satisfacer la demanda nacional de arroz que superan las 850 000 toneladas anuales, por lo que en los últimos años se ha recurrido a la importación. Ante ello, a fin de contrarrestar esta situación, se ha incentivado el desarrollo de tecnologías propias a los sistemas de producción y la implementación de programas de mejoramiento genético orientados a la generación de genotipos y su adaptación a las zonas arroceras del país. A pesar de los esfuerzos, aun se carece de variedades de arroz de grano largo y delgado que son de buena calidad industrial del grano y competitivo con los arroces de importación; además, que son preferidos por el consumidor. En consecuencia, en la región arrocera de Michoacán se identificaron líneas de arroz avanzadas, donde surgió el genotipo Lombardía FLAR 13. Durante los ciclos 2017 a 2020 este material fue evaluado experimentalmente en comparación con el genotipo Milagro Filipino en Lombardía, municipio de Gabriel Zamora, Michoacán. Se registraron variables morfológicas y productivas. Con los datos obtenidos además de la verificación de las pruebas de normalidad y homogeneidad de varianzas, se analizaron con la prueba estadística t-student para muestras independientes. Los resultados mostraron superioridad del genotipo Lombardía FLAR 13 sobre el genotipo Milagro Filipino, ya que en la mayoría de las variables morfológicas evaluadas igualó, e incluso superó en las variables productivas, particularmente en esta última, los rendimientos fueron superiores a 9 t ha-1, además presentó estabilidad productiva durante los ciclos evaluados, por lo que es competitivo con la variedad convencional Milagro Filipino que se establece en la zona.

ABSTRACT The bioavailability of a nutrient in a food serves to determine the nutritional quality for human consumption. Rice is one of the most important foods in diet due to its caloric and nutritional contribution. The objective of this study was to analyze the in vitro bioavailability of zinc in rice by ultraviolet-visible spectrophotometry and flame atomic absorption spectrometry and its relationship with phytic acid content. The percentage of zinc bioaccessibility with respect to phytic acid percentage, showed an inverse proportional logarithmic relationship (r= −0.669; p<0.05). The percentage values of zinc bioavailability and phytic acid in the evaluated rice varieties had a range of 1.9-8.7% and 0.039-0.946%, respectively. Phytic acid affected the bioaccessibility of zinc and was not linked to the total concentration of zinc present in the rice lines evaluated. The techniques implemented to quantify zinc dialyzed presented significant differences. It was shown that the ultraviolet-visible technique was not suitable for this type of assay.

RESUMEN La bioaccesibilidad de un nutriente en un alimento sirve para determinar la calidad nutricional de éste para el consumo humano. El arroz es uno de los alimentos más importantes en la dieta por su gran aporte calórico y nutricional. El objetivo de este estudio fue analizar la bioaccesibilidad in vitro del zinc en arroz mediante espectrofotometría ultravioleta-visible y espectrometría de absorción atómica de llama y su relación con el contenido de ácido fítico. El porcentaje de bioaccesibilidad del zinc, respecto al porcentaje de ácido fítico, presentó una relación logarítmica inversamente proporcional (r= −0,669; p<0,05). Los valores porcentuales de bioaccesibilidad del zinc y ácido fítico en las líneas de arroz evaluadas se hallaron en un rango de 1,98,7% y 0,039-0,946% respectivamente. Se encontró que el ácido fítico afecta la bioaccesibilidad del zinc y que ésta no estuvo ligada a la concentración total del zinc presente en las líneas de arroz evaluadas. Las técnicas implementadas para cuantificar el zinc dializado presentaron diferencias significativas y se mostró que la técnica ultravioleta-visible no fue apta para este tipo de ensayos.

ABSTRACT. This study presents self-organizing maps (SOM) as an alternative method to evaluate genetic diversity in plant breeding programs. Twenty-five genotypes were evaluated in two environments for 11 phenotypic traits. The genotypes were clustered according to the SOM technique, with variable topology and numbers of neurons. In addition to the SOM analysis, unweighted pair group method with arithmetic mean clustering (UPGMA) was performed to observe the behavior of the clustering when submitted to these techniques and to evaluate their complementarities. Genotype ordering according to SOM was consistent with UPGMA results, evidenced by the basic structure of UPGMA groups being preserved in each group of the maps. Regarding genotype arrangement and the group neighbors, maps involving five neurons presented inferior organization efficiency compared to the six-map arrangements in both environments. It was observed that the organization pattern among the rice genotypes evaluated by the maps was complementary to the UPGMA approach, as observed in all scenarios. It can be concluded that self-organizing maps have the potential to be useful for genetic diversity studies in breeding programs.

In the central zone of Mexico, rice (Oryza sativa L.) is planted under transplant and in direct sowing under irrigation; most varieties have been released for transplant. In 2005, one of these lines was used as a parent and continued with the generational advance to F5. In 2011, a preliminary performance test was carried out on several groups of lines, around 256 materials, from which C14Za06 was identified as outstanding (currently, Var. Morelos A-2016). In 2014 and 2015 different lines were evaluated in performance trials in the towns of Zacatepec, Jojutla, Emiliano Zapata, Mazatepec, Coatlan del Río and Cuautla, Morelos state; in addition to the commercial witness Morelos A-2010. Of the evaluated materials, C14Za06 stood out for its yield superior to 10 t ha-1, moderate resistance to pyricularia, high tolerance to grain staining, semi-erect growth habit, plant height of 130 cm, resistant to lodging; industry performance of 57% whole polished grain; conserving the Morelos quality (20% of white center).

Resumen En la zona central de México se siembra el arroz (Oryza sativa L.) bajo trasplante y en siembra directa bajo riego; la mayoría de las variedades se han liberado para trasplante. En 2005 una de estas líneas se usó como progenitor y continuándose con el avance generacional hasta F5. En 2011 se realizó una prueba preliminar del rendimiento de varios grupos de líneas, alrededor de 256 materiales, de donde se identificó como sobresaliente a C14Za06 (actualmente, var. Morelos A-2016). En 2014 y 2015 se evaluaron diferentes líneas en ensayos de rendimiento en las localidades de Zacatepec, Jojutla, Emiliano Zapata, Mazatepec, Coatlán del Rio y Cuautla, estado de Morelos; además del testigo comercial Morelos A-2010. De los materiales evaluados sobresalió la C14Za06 por rendimiento superior a 10 t ha-1, moderada resistencia a pyricularia, alta tolerancia a manchado de grano, habito de crecimiento semierecto, altura de planta de 130 cm, resistentes al acame; rendimiento en industria de 57% de grano pulido entero; conservando la calidad Morelos (20% de centro blanco).

Abstract In Mexico, long and thin rice is the most consumed, so its supply has depended mainly on imports. Consequently, the Mexican Rice Council handed INIFAP the elite lines that generated the Latin American Rice Irrigation Fund (FLAR) for the evaluation and selection of materials. In order to validate advanced lines of long and thin grain rice compared to conventional material under the conditions of the Michoacán production area, experimental works were developed in different cycles: autumn-winter 2014-2015 (trial 1), spring summer from years 2015 (trial 2), 2016 (trial 3) and 2017 (trial 4) and different genotypes: trial 1) INIFLAR RT, FL05601, “Milagro Filipino”; test 2) FL06747, FL08224, INIFLA R, INIFLAR RT, Ivory, Lombardy, “Milagro Filipino”; essay 3) Lombardy, FL08224, “Milagro Filipino”; and essay 4) Ivory, Lombardy “Milagro Filipino 2. The data recorded varied in each trial, but phenological and productive aspects were included, including yield. Analysis of variance and comparison of means were performed. In trial 1, treatments exceeded the regional average, between 8,000 and 8,500 kg ha-1. In trial 2, the treatments FL06747, INIFLAR R and Lombardy stood out significantly in performance. Also, the flowering and maturity of grain, appeared early compared to “Milagro Filipino”. In trials 3 and 4, the Lombardy treatment showed higher yields. It is concluded that the advanced lines presented capacity to adapt to the production area of Michoacán. These materials were superior to the conventional material, since they showed consistency in each trial.

Resumen En México el arroz largo y delgado es de mayor consumo, por lo que su abasto ha dependido principalmente de importaciones. Consecuentemente, el Consejo Mexicano del Arroz entregó al INIFAP líneas élite que generó el Fondo Latinoamericano de Arroz de Riego (FLAR) para evaluación y selección de materiales. Con el objetivo de validar líneas avanzadas de arroz de grano largo y delgado comparadas con el material convencional bajo las condiciones de la zona productora de Michoacán, trabajos experimentales fueron desarrollados en diferentes ciclos: otoño-invierno 2014-2015 (ensayo 1), primavera verano de los años 2015 (ensayo 2), 2016 (ensayo 3) y 2017 (ensayo 4) y diferentes genotipos: ensayo 1) INIFLAR RT, FL05601, “Milagro Filipino”; ensayo 2) FL06747, FL08224, INIFLA R, INIFLAR RT, Marfil, Lombardía, “Milagro Filipino”; ensayo 3) Lombardía, FL08224, “Milagro Filipino”; y ensayo 4) Marfil, Lombardía “Milagro Filipino”. Los datos registrados variaron en cada ensayo, pero se incluyeron aspectos fenológicos y productivos, incluido el rendimiento. Se realizaron análisis de varianza y comparación de medias. En el ensayo 1, los tratamientos superaron a la media regional, entre 8 000 a 8 500 kg ha-1. En el ensayo 2, los tratamientos FL06747, INIFLAR R y Lombardía sobresalieron significativamente en rendimiento. También la floración y madurez de grano, se presentó precozmente comparado con “Milagro Filipino”. En los ensayos 3 y 4, el tratamiento Lombardía presentó rendimientos superiores. Se concluye que las líneas avanzadas presentaron capacidad de adaptación a la zona productora de Michoacán. Estos materiales fueron superiores al material convencional, ya que mostraron consistencia en cada ensayo.

According to international experience, grain losses due to poor regulation of the reel have a significant weight (approximately between 33 and 73%) within the total losses attributable to the rice harvesters, being able to reach up to 23% of the total harvested product. The national practice of regulating the windlass during the mechanized harvesting of rice does not include the application of scientific principles that are established internationally in the theory of agricultural machinery. Consequently, it is necessary to carry out studies where these concepts are applied, to perfect the harvesting process, minimizing the losses attributable to poor regulation of this body of work. These conceptual models were applied and computerized programmed. As input data they were taken: the construction, exploitation and regulation parameters of the windlass of the combined Claas-Crop Tiger 30, used in production conditions (Agro industrial Grain Company of Amarillas locality, Matanzas province) and the properties of the harvested crop (Oriza sativa, variety “Reforma”). As a result, it was determined that, most of the requirements for good windmill exploitation are not met. Correction of exploitation and regulation parameters is proposed to minimize the losses attributable to the action of this body of work

De acuerdo a la experiencia internacional, las pérdidas de granos debido a una deficiente regulación del molinete, presentan un peso importante (aproximadamente entre 33 y 73%) dentro de las pérdidas totales achacables a las máquinas cosechadoras de arroz, pudiendo alcanzar hasta un 23% del total del producto cosechado. La práctica nacional de regulación del molinete durante la cosecha mecanizada del arroz, no incluye la aplicación de principios científicos que están establecidos internacionalmente en la teoría de máquinas agrícolas, por lo que se hace necesario efectuar estudios donde se apliquen estos conceptos, de manera de perfeccionar el proceso de cosecha, minimizando las pérdidas achacables a una mala regulación de este órgano de trabajo. Como resultado de la aplicación y programación computarizada de estos modelos conceptuales, y tomando como datos de entrada los parámetros constructivos, de operación y de regulación del molinete de la combinada Claas-Crop Tiger 30, empleados en condiciones de producción (Empresa Agroindustrial de Granos de la localidad de Amarillas, provincia de Matanzas) y las propiedades del cultivo cosechado (Oriza sativa, variedad “Reforma”) se determinó que no se satisface la mayor parte de los requisitos exigidos para un buen funcionamiento del molinete, proponiéndose la corrección de los principales parámetros de operación y regulación, con vistas a minimizar las pérdidas achacables a la acción de este órgano de trabajo

Resumo O objetivo deste trabalho foi determinar a influência da tensão de água e de atributos físicos e químicos do solo sobre a produtividade do arroz irrigado por aspersão, em terras baixas no Rio Grande do Sul. Na safra 2011/2012, foram avaliados os efeitos das tensões de água no solo de 20 e 40 kPa, durante todo o ciclo da cultura, bem como as de 40 e 20 kPa nas fases vegetativa e reprodutiva, respectivamente. Na safra 2012/2013, foram avaliadas as tensões de 10, 20 e 40 kPa, durante todo o ciclo da cultura, e as de 40 e 10 kPa nas fases vegetativa e reprodutiva, respectivamente. Em ambas as safras, utilizou-se a cultivar de arroz irrigado BRS Pampa. O gasto com água na irrigação por aspersão representou 48% do gasto com a irrigação por inundação. A produtividade do arroz correlacionou-se positivamente com a microporosidade e com os teores de fósforo e potássio disponíveis no solo; e negativamente com a macroporosidade e a saturação por alumínio. A avaliação conjunta da tensão de água e de atributos físicos e químicos do solo permite avaliar com mais propriedade a variabilidade na produtividade de arroz irrigado por aspersão em terras baixas no Rio Grande do Sul. A irrigação por aspersão possibilita melhor uso da água proveniente da precipitação pluvial, com efeitos positivos sobre a economia de água.

Abstract The objective of this work was to determine the effect of soil water tension and physicochemical soil attributes on sprinkler-irrigated rice yield in lowlands of the state of Rio Grande do Sul, Brazil. In the 2011/2012 crop season, the effects of 20 and 40 kPa soil water tensions throughout the crop cycle were evaluated, as well as of 40 and 20 kPa during the vegetative and reproductive phases, respectively. In the 2012/2013 crop season, soil water tensions of 10, 20, and 40 kPa were evaluated throughout the entire crop cycle, and the tensions of 40 and 10 kPa were evaluated during the vegetative and reproductive phases, respectively. In both crop seasons, the irrigated rice cultivar BRS Pampa was used. Water costs with sprinkler irrigation represented 48% of that with flood irrigation. Rice yield was positively correlated with soil microporosity and phosphorus and potassium availability; and negatively correlated with macroporosity and aluminum saturation. The joint evaluation of soil water tension and soil physicochemical attributes allow a better evaluation of the variability of sprinkler-irrigated rice yield in the lowland areas of the state of Rio Grande do Sul. Sprinkler irrigation allows better use of rainwater, revealing positive effects on water economy.

RESUMO O cultivo de arroz (Oryza sativa) de terras altas no Brasil ocorre principalmente em área de Cerrado, região que apresenta condições climáticas adversas. A utilização do silício em seu cultivo torna-se importante de vez que este nutriente proporciona maior rigidez, menor transpiração e maior resistência a veranicos em plantas de arroz. No presente estudo, objetivou-se avaliar o efeito da adubação silicatada e tensões de água do solo no desenvolvimento e rendimento de arroz de terras altas em Latossolo Vermelho do Cerrado. Utilizou-se esquema fatorial 5 x 5 fracionado com cinco manejos de irrigação baseados nas tensões de água no solo (0, 15, 30, 45 e 60 kPa) e cinco doses de silício (0, 120, 240, 480 e 960 mg dm-3) as quais foram distribuídas segundo delineamento de blocos ao acaso, com quatro repetições. Foram avaliados: altura de plantas, número de perfilhos, número de panículas, número de grãos por panícula, número de grãos cheios e chochos e porcentagem de grãos chochos. Adubação silicatada promove o aumento do perfilhamento em plantas de arroz com a dose de 960 mg dm-3. Ocorreu um decréscimo de produção de perfilhos e número de panículas com a aplicação de silício até as doses de 460 e 490 mg dm-3, respectivamente. O aumento das tensões de água no solo reduziu a altura e o número de grãos cheios, e aumentou a porcentagem de grãos chochos de arroz de terras altas.

ABSTRACT The cultivation of upland rice (Oryza sativa) in Brazil occurs mainly in the Cerrado, a region with adverse weather conditions. The use of silicon in its cultivation becomes important, since this nutrient provides higher rigidity, lower transpiration and higher resistance to dry spells in rice plants. The objective of the present study was to evaluate the effect of silicon fertilization and soil water tensions on upland rice development and yield in a Cerrado Oxisol. A 5 x 5 fractionated factorial with five soil water tensions (0, 15, 30, 45 and 60 kPa) and five silicon doses (0, 120, 240, 480 and 960 mg dm-3) was used, which were distributed in a randomized block design, with four replicates. Plant height, number of tillers, number of panicles, number of grains per panicle, numbers of full and empty grains and percentage of empty grains were evaluated. Silicon fertilization promotes increased tillering in rice plants at the dose of 960 mg dm-3. The numbers of tillers and panicles decreased with the application of silicon up to the doses of 460 and 490 mg dm-3, respectively. The increase in soil water tensions reduced plant height and the number of full grains, and increased the percentage of empty grains of upland rice.

: El objetivo de este estudio fue evaluar in vitro la resistencia de bacterias endófitas a diferentes concentraciones de níquel (Ni). Se recolectaron muestras de tejidos de plantas de arroz cultivadas en el municipio de Montelíbano, Córdoba, Colombia. Cada tejido fue sometido a un proceso de desinfección superficial para obtener el aislamiento de bacterias endófitas en el medio de cultivo agar R2A. Se aislaron 33 morfotipos de bacterias endófitas, obtenidos de raíz, macolla y hoja de diferentes variedades comerciales de arroz. Se determinó la densidad poblacional (UFC/g de tejido) por conteo en superficie y la separación de los morfotipos se realizó mediante la forma, color, tamaño y textura de las colonias bacterianas. La resistencia al Ni se evaluó in vitro con diferentes concentraciones de Ni en forma de NiCl2.6H2O y las bacterias que mostraron resistencia fueron identificadas mediante secuenciación molecular. Los resultados de la prueba de resistencia a Ni mostraron capacidad de las bacterias endófitas de crecer a concentraciones de 0,1 hasta 0,3 mg/L de Ni. Los resultados de la identificación molecular confirmaron la presencia de Aeromonas hydrophila como bacteria endófita aislada de la variedad comercial de arroz Fedearroz 2000, con la capacidad de resistir hasta 0,3 mg/L de Ni.

The aim of this work was to study the in vitro resistance of endophytic bacteria to different nickel (Ni) concentrations. Tissue samples from rice plants cultivated in the municipality of Montelíbano, Cordoba, Colombia were collected. Each specimen was submitted to surface disinfection process for the isolation of endophytic bacteria from culture in R2A agar medium. Thirty three (33) morphotypes of endophytic bacteria were obtained from root and leaf clump of different commercial varieties of rice plants. Tissue population density (CFU/g) was determined by surface counting and morphotypes separation was performed by shape, color, size and texture of the bacterial colonies. Nickel resistance in vitro was evaluated with different concentrations of Ni and NiCl2.6H2O and bacteria that showed resistance were identified by molecular sequencing. The test results showed resistance to Ni of the endophytic bacteria by their ability to grow at concentrations of 0.1 to 0.3 mg/L of Ni. The molecular identification results confirmed the presence of Aeromonas hydrophila as endophytic bacteria isolated from the commercial rice variety Fedearroz 2000, with the ability to grow in presence of concentrations of 0.3 mg/L of Ni.

A utilização de efluentes industriais tratados na irrigação do arroz por alagamento pode provocar alterações eletroquímicas e aumentar o teor de nutrientes na solução do solo. Para testar essa hipótese, este trabalho teve por objetivo avaliar a dinâmica dos atributos químicos e eletroquímicos da solução do solo sob cultivo de arroz irrigado com lixiviado industrial tratado, contendo 820 mg L-1 de Na. O experimento foi conduzido em casa de vegetação, utilizando-se como unidades experimentais vasos preenchidos com 20 kg de solo, em delineamento experimental em blocos casualizados, com três repetições. Os tratamentos foram: controle (irrigação com água destilada) e quatro proporções do lixiviado (25, 50, 75 e 100 %). As coletas de solução do solo foram feitas semanalmente a partir do quarto dia após o início do alagamento (DAA) até 84 DAA. A solução do solo foi amostrada na profundidade de 10 cm e analisada para os principais nutrientes e o Na, bem como para a demanda bioquímica de oxigênio (DBO5), relação de adsorção de sódio (RAS), condutividade elétrica (CE) e potencial redox (EH). A irrigação com o lixiviado aumentou os teores de K, Ca, Mg, S, P, N-NH+4, N-NO−3 e Na, assim como os valores de RAS e CE, para valores considerados prejudiciais para as plantas. Foi observada diminuição do potencial redox na solução do solo pela irrigação com lixiviado industrial tratado. Os teores de DBO5 e o N-NH+4 diminuíram com o tempo de alagamento. Em proporções menores que 25 %, o lixiviado industrial tratado pode aumentar os teores de nutrientes em solução sem causar interferência do Na para as plantas.

The use of treated industrial wastewater in flood irrigation of rice may cause electrochemical changes and increase the nutrient content in the soil solution. To test this hypothesis, the aim of the present study was to evaluate the dynamics of the chemical and electrochemical properties of the soil solution under flooded rice irrigated with treated industrial leachate containing 820 mg L-1 of Na. The experiment was conducted in a greenhouse, using pots filled with 20 kg of soil in a randomized block design with three replications. The treatments were control (irrigation with distilled water) and four ratios of the leachate (25, 50, 75, and 100 %). Samples of soil solution were taken weekly from the fourth day after the start of flooding (DAF) until 84 DAF, The soil solution was sampled by means of 50 mm diameter PVC collectors at 10 cm depth, and analyzed for key nutrients and Na, as well as for biochemical oxygen demand (BOD), sodium adsorption ratio (SAR), electrical conductivity (EC), and redox potential (EH). Irrigation with leachate increased the levels of Ca, Mg, S, P, NH+4 -N, NO−3-N and Na, as well as the values of the SAR and the value of EC, to levels considered harmful to plants. A decrease in EH was observed in the soil solution through irrigation with treated industrial leachate. The levels of BOD5 and NH+4 -N decreased with time of flooding. At proportions of less than 25 %, the treated industrial leachate can increase the levels of nutrients in the soil solution without Na reaching critical levels for plants.

Os metais pesados podem-se acumular no solo, causando fitotoxicidade em plantas, apresentando alguns sintomas específicos. Por esta razão, este estudo avaliou os sintomas específicos, em plantas de arroz e de soja, causados por excesso de metais pesados no solo. As plantas de arroz e de soja foram cultivadas em vasos, contendo solos com diferentes quantidades de metais pesados. O delineamento experimental foi inteiramente casualizado, com quatro repetições, utilizando-se duas culturas e sete amostras de solos com diferentes níveis de contaminação. As plantas de arroz e de soja exibiram diferentes respostas às elevadas concentrações desses metais no solo. Por exemplo, altas concentrações de Zn disponível no solo causaram fitotoxicidade no arroz e na soja, principalmente cloroses e inibição do crescimento das plantas. As plantas de arroz acumularam maiores teores de Cu, Mn, Pb e Zn e foram mais sensíveis às concentrações elevadas desses elementos no solo, absorvendo-os mais facilmente do que as plantas de soja. Além disso, altas concentrações de Zn no solo reduziram a concentração de Fe na parte aérea das plantas de soja e de arroz para níveis considerados deficientes.

Heavy metals can accumulate in soil and cause phytotoxicity in plants with some specific symptoms. The present study evaluated the specific symptoms on rice and soybeans plants caused by excess of heavy metals in soil. Rice and soybean were grown in pots containing soil with different levels of heavy metals. A completely randomized design was used, with four replications, using two crop species and seven sample soils with different contamination levels. Rice and soybean exhibited different responses to the high concentrations of heavy metals in the soil. Rice plants accumulated higher Cu, Mn, Pb and Zn concentrations and were more sensitive to high concentrations of these elements in the soil, absorbing them more easily compared to the soybean plants. However, high available Zn concentrations in the soil caused phytotoxicity symptoms in rice and soybean, mainly chlorosis and inhibited plant growth. Further, high Zn concentrations in the soil reduced the Fe concentration in the shoots of soybean and rice plants to levels considered deficient.

Se evaluó el efecto en el crecimiento y desarrollo de plantas de arroz Paddy,Oryzasativa L. variedad comercial FEDEARROZ 733, inoculado con la cepa nativa Azospirillum(A5), comparado con un testigo absoluto y un testigo comercial (Urea). Se realizó la multiplicación delabacteria a diferentes concentraciones: 106, 107 y 108 UFC, en el medio de cultivo NFB líquido a 24°C, agitación constante e incubación por 72 horas. El estudio se realizó bajo condiciones de invernadero con suelo con bajo contenido de materia orgánica; las semillas fueron embebidas en las diferentes concentraciones bacterianas. Se utilizó un diseño en bloques completos al azar con tres repeticiones y cinco tratamientos: testigo absoluto, testigo comercial y las concentraciones bacterianas 106,107 y 108 UFC. Se evaluaron las variables altura de planta, longitud de las raíces, número de macollas planta y peso seco/planta, a los 30, 60, 90 y 120 días después de germinación. El número de panículas/planta, número de granos/planta y el rendimiento en granos se midieron al momento de la cosecha. La concentración107 UFC produjo 3,74 g/planta; éste valor fue similar al obtenido utilizando fertilizante nitrogenado, demostrándose que las inoculaciones influyen en el crecimiento y producción de las plantas de arroz.

It was evaluated the Paddy plants rice, Oryza sativa L. var. FEDEARROZ 733, growth and develoment effect, inoculated with the Azospirillum (A5) native strain compared with absolute and commercial control (Urea).The multiplication of the bacterium at different concentrations: 106, 107 y 108 UFC, was performed in the liquid culture medium NFB, temperature of 24°C, constant agitation and time of 72 hours of incubation. The assay was conducted under greenhouse conditions, using plastic pots with soilwithlow organic matter content andrice seed previously inoculated;a design in complete blocks at random with three repetitions and fivetreatments was used:absolute control, commercial control and concentrations, 106 UFC, 107 UFC and 108 UFC. Height of plant, length of the roots, number of tiller/plant and dry weight/plants, were evaluated 30, 60, 90 and 120 days after germination. The number of panicles/plants, number of grains/plants and the grain yield by plant were evaluated at the time of the harvest. Concentration of 107 UFC/mL produced3,74, g/plant; this value was similar to that obtained using nitrogen fertilizer, demonstrating that inoculations influence growth and production of rice plants.

O efeito no crescimento e desenvolvimento de plantas de arroz paddy, Oryza sativa L. variedade comercial FEDEARROZ 733, inoculados com cepa nativa Azospirillum (A5), em comparação com o controle absoluto e um controle comercial (uréia). Foi realizada a multiplicação de bactérias em concentrações diferentes: 106, 107 e 108 UFC no meio de cultura líquido NFB a 24 0C sob agitação constante e incubação durante 72 horas. O estudo foi conduzido em casa de vegetação com baixo teor de matéria orgânica do solo, as sementes foram embebidas em diferentes concentrações bacterianas. Foi utilizado um delineamento em blocos casualizados com três repetições e cinco tratamentos: controle absoluto, controle comercial e concentrações bacterianas 106,107 e 108 UFC. As variáveis foram avaliadas a altura da planta, comprimento da raiz, número de perfilhos e peso seco da planta / planta aos 30, 60, 90 e 120 dias após a germinação. O número de panículas / planta, número de sementes / planta eo rendimento de grãos foram medidos no momento da colheita. Concentraçãode 107 CFU produziu 3,74 g/planta; este valor foi similar à obtida com fertilizante de azoto, demonstrando que as inoculações influenciar o crescimento e a produção de plantas de arroz.

This study aimed to define the process conditions to obtain snacks from the by-products of rice and soybean with physical characteristics suitable for marketing. Therefore, the effects of moisture and extrusion temperature on the expansion and color of the products obtained experimentally obtained were evaluated, and the proximate composition of the by-products and that of the snack with greater desirability were determined. Response surface methodology and rotational central composite design were used, and desirability test based on the regression models adjusted was applied. The most desirable snack, with the highest expansion index (3.39), specific volume (13.5 mL.g-1), and the chromaticity coordinate a* (2.79), was obtained under 12 g.100 g-1 moisture and 85ºC of temperature in the third zone of the extruder. The snack produced under these conditions attained content of protein and lipid content 41 and 64% higher than that of the traditional corn snack. It can be concluded that producing extruded snack made form a mixture of broken grains, rice bran, and soybean okara (81:9:10) is technologically feasible, enabling the development of a new product with good nutritional value that can improve the diet of children, the main consumers of this type of food.