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Minimum tillage in rice production is increasing in southern Brazil, reaching 60% of the total planted area. Compared to conventional tillage, in this system there is an increase in the occurrence of perennial weeds, such as Luziola peruviana and Leersia hexandra, which are amphibious plants, as they can occur in both flooded environments and aerobic conditions. These weeds are controlled in burn-down before rice planting by glyphosate applications, the efficacy of which depends on the soil moisture. This study aimed to evaluate the effect of different soil moisture regimes in L. hexandra and L. peruviana growth and photoassimilate partitioning. Both species were assessed under soil moisture regimes of flooded, saturated, 7 kPa, 15 kPa, 40 kPa, and 100 kPa (experiment 1) and flooded, saturated, and 7 kPa (experiment 2). Plants were sampled immediately after drainage (3 months after transplant) and 1 and 2 weeks after drainage. The results showed that as soil moisture levels decreased, growth and development parameters were negatively affected in both species. Photoassimilate partitioning was affected by water regime and differences were observed between species. The total soluble sugars and starch content decreased in the leaves, and sucrose concentration increased in the roots following drainage. Soil drainage affects the growth and alters carbohydrate partitioning of these weeds, increasing the sugar storage in roots. The agronomic impact of these findings is that this behavior may affect herbicide transport in phloem and may affect herbicide efficacy.

Na busca por respostas quanto às condições de bem-estar animal, visou-se a avaliar neste trabalho o comportamento de pintainhos nas duas primeiras semanas de vida, por meio de processamento de imagens digitais. O experimento foi realizado em dois galpões comerciais, utilizados para criação de 15.200 aves de corte por galpão, durante um ciclo produtivo, dotados com fornalha a lenha de aquecimento indireto do ar. Foram instaladas duas câmeras de vídeo por galpão para aquisição de imagens digitais. Uma das câmeras possuía inclinação angular de 45º, e a outra, inclinação angular de 90º em relação ao solo. As imagens foram analisadas para cada condição climática diária e binarizadas, sendo depois processadas por meio de descritor de agrupamento/dispersão e correlacionadas com os valores de temperatura do ar. Observou-se correlação entre o descritor e os valores de temperatura do ar, sendo que as imagens obtidas pela câmera posicionada a 45º e divididas em 25 blocos, obtiveram maior correlação. Pelos dados obtidos, pode-se observar que o comportamento de agrupamento e dispersão dos pintainhos pode ser usado como indicador dos estados de conforto térmico e que o descritor se mostrou eficiente para esta quantificação.The aim of this study was to evaluate the behavior of young chickens in the first two weeks of life through digital images processing, for the determination of the best condition of animal welfare. The experiment was accomplished at two buildings with furnace with indirect air heating, used for creation of 15,200 broiler chickens by building, during one single productive cycle. For the production of digital images, two video cameras were installed by building. One of the cameras had an inclination of 45º and the other a 90º in relation to the ground. The images were analyzed for each daily climatic condition. Then, they were binarized and processed through grouping/dispersion descriptor and correlated with the values of temperature of the air. Correlation was observed between the descriptor and the values of temperature of the air. Images obtained by the camera positioned at 45º had the highest correlation. From the data obtained can be observed that the grouping/dispersion and the behavior of the young chickens can be used as indicator of the states of thermal comfort and that the descriptor was efficient for the quantification.

The objective of this work was to evaluate the width and length incidence in a single seed fraction of oat [Avena sativa (L.)] cv. Cristal. The seeds were selected by a mechanical divider and by hand, and their correspondence to radiographic images in seeds with glumes and their caryopses. The width and length of the seeds with glumes and their caryopses were measured with electronic calliper, and their weight, with precision balance. Radiographic images of seeds with glumes were taken with an X-ray experimental equipment. The analyst selected seeds with glumes by the width and by the length previously determined and so with more weight, than that obtained by hand selection was slightly narrower, larger and lighter. The presence of the glumes masked the caryopses real dimensions (width and length), and conduced the analyst to select seeds that differed more by the width than by the length. The radiographic images showed the presence, or not, of caryopses inside the seed and its real dimensions. The mechanical partition method for seeds showed to be more efficient because the analyst subjectivity was not considered when the selection upon its dimensions was done. The X-ray analysis was a useful tool that complements the pure seed fraction selection as another factor of seed quality.

El objetivo de este trabajo fue estudiar las alteraciones producidas por el deterioro en semillas de soja (Glycine max L. Merrill) utilizando diferentes pruebas de vigor. Se utilizaron semillas de soja de diferentes cultivares en 1997 y 1998, las cuales fueron sometidas a la prueba de germinación y diferentes pruebas de vigor: envejecimiento acelerado; conductividad eléctrica; deterioro controlado y tetrazolio. El deterioro controlado en semillas con 22% de humedad mostró ser un mejor indicador de la disminución del vigor de la semilla de soja que el envejecimiento acelerado. La conductividad eléctrica en semillas individuales podría ser considerada una buena prueba de vigor para detectar alteraciones producidas en las membranas citoplasmáticas en un estadio temprano del deterioro de las semillas. La clasificación de la viabilidad y el vigor a través de la prueba de tetrazolio está dada por el lugar donde se produce el daño y no por el tipo de daño que sufre la semilla.

El objetivo del trabajo fue estudiar el comportamiento de glicinina y beta-conglicinina y la actividad de alfa-amilasa en semillas deterioradas y no deterioradas de 10 cultivares de soja [Glycine max (L.) Merr.]. Las semillas se sometieron a dos tratamientos: deterioradas por envejecimiento acelerado y no deterioradas. Se determinó la presencia de las proteínas de reserva a partir de semillas con 0, 3 y 8 días de germinadas por electroforesis en geles de poliacrilamida (SDS-PAGE). La actividad de la alfa-amilasa se determinó bioquímicamente en semillas con 0, 3, 8 y 12 días de germinadas. No hubo diferencias en la presencia de bandas de glicinina y beta-conglicinina en semillas no deterioradas hasta los 8 días de germinadas. Las semillas deterioradas se comportaron en forma similar a las no deterioradas. La actividad de la alfa-amilasa aumentó en semillas germinadas hasta 8 días y disminuyó a los 12 días. En semillas deterioradas la actividad enzimática disminuyó con respecto a las no deterioradas. El deterioro artificial no afectó la presencia de glicinina y beta-conglicinina pero alteró la actividad de la alfa-amilasa hasta los 12 días de germinación. Los cultivares estudiados mostraron comportamiento diferencial frente a la actividad de esta enzima.