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The aim of the present study was to investigate the potential allelopathic effects of isolated or intercropped aqueous forage extracts on the physiological performance of soybean [Glycine max (L.) Merr.] and corn (Zea mays L.) seeds, as well as their phytotoxicity to the weed species Bidens pilosa L. Aqueous extracts were prepared at a concentration of 5%, and the tests with soy and corn were conducted by wetting the germination papers with different treatments and performing procedures within the standards of the Brazilian Rules of Seed Analysis. Tests with the cover plant extracts on the seeds of B. pilosa used BOD-type repetitions. Fifty weed seeds were placed in a gerbox with filter paper moistened with the different treatments with five repetitions. Distilled water was used as the control in all tests. Extracts of Avena strigosa Schreb and Raphanus sativus L. (radish), cultivated individually and in combination, increased the seed germination percentage (%G) and the length of soybean seedlings. Similarly, extracts of Pennisetum glaucum (L.) R.Br and Crotalaria spectabilis Roth, in individual and combined cultivation, provided gains in corn %G. Furthermore, all tested extracts suppressed germination and decreased the speed of the germination index of the hairy beggarticks when compared to the control, with the radish extract showing the greater reduction effect on the %G of the weed plant B. pilosa. Highlights: • The use of Crotalaria as a cover crop has a positive effect on the initial growth of corn. • The use of black oat and forage radish intercropped had the potential to increase soybean yield. • The use of cover crops contributes to the integrated management of weeds. • The choice of cover plant is important for the success of crop rotation.

A sensitive and reliable process was established using high-performance liquid chromatography (HPLC) to distinguish conventional varieties of glyphosate-resistant genetically modified crops via shikimate detection in soybean (Glycine max L. Merril) seeds. Glyphosate has a well-defined mechanism of action. It is the only herbicide that specifically inhibits 5-enolpiruvilshikimate-3-phosphate synthase (EPSPS E.C. 2.5.1.19), which catalyzes the condensation of shikimate with phosphoenolpyruvate. This study is based on the concept that shikimate significantly accumulates in soybean plant tissues after EPSPS inhibition by glyphosate. In plants not subjected to glyphosate, shikimate is not easily detected because it quickly metabolizes into shikimate 3-phosphate and subsequently into 5-enolpiruvilshikimate 3-phosphate through the action of EPSPS. Conversely, in non-genetically modified plants subjected to glyphosate, shikimate metabolism is impaired, resulting in its accumulation. This metabolite can be detected in extremely low quantities (in the microgram range), through HPLC. In this study, six different contrasts were analyzed, each being formed by a transgenic cultivation and its parental strain, subject or not subject to the treatment of soaking with a 0.6% glyphosate solution. Chromatographic analyses indicated shikimate accumulation only in conventional cultivars with seeds previously soaked in a 0.6% glyphosate solution. Thus, this shikimate detection method can be used as a rapid and accurate means to distinguish soybeans with glyphosate-resistant qualities.

Low temperature stress affects plant growth, including primary and secondary metabolism. Glyphosateresistant soybean contains a modified DNA, which encodes a different type of secondary metabolism enzyme related to lignin synthesis compared to conventional glyphosate-susceptible cultivars. Thus, this soybean cultivar might respond differently to low temperatures, compared to glyphosate-susceptible cultivars. This work aimed to investigate how decreasing temperatures influence the growth and lignin content of the glyphosate-resistant soybean compared to its susceptible parental cultivars. Three-day-old seedlings were cultivated in nutrient solution at 10, 15, 20, and 25°C (±2°C), using a 12-h photoperiod. After 96 h, taproot growth, fresh and dry biomass, and lignin levels were determined. The results indicate that lower temperatures decreased seedling and root growth in both types of cultivars; however, glyphosate-resistant soybean exhibited greater root length, biomass, and lignin content compared to the glyphosate-susceptible parental cultivar. O estresse causado pela baixa temperatura, dentre outras implicações, afeta o crescimento do vegetal assim como o seu metabolismo secundário. Pelo fato da soja RR apresentar variante enzimática de uma das principais vias do metabolismo secundário, ligada à síntese de lignina, pode apresentar comportamento diferenciado, sob baixa temperatura, se comparada com sua linhagem parental. O objetivo deste trabalho foi investigar possíveis diferenças no crescimento e nos conteúdos de lignina nas raízes de soja cultivar transgênica resistente ao glifosato e cultivar parental em resposta a redução de temperatura. Após três dias de germinação das sementes, as plântulas foram mantidas em solução nutritiva, a 10, 15, 20 e 25°C (±2°C), com fotoperíodo de 12 horas. Após 96 horas, foi avaliado o comprimento relativo da raiz primária, biomassa fresca e seca das raízes e os teores de lignina. Os resultados mostram que a baixa temperatura promoveu redução no crescimento das plântulas e raízes. Dentre as cultivares em estudo, a soja transgênica apresentou maior comprimento relativo, biomassas e teores de lignina.

Avaliou-se, sob duas densidades de plantio, um variante somaclonal de porte baixo de bananeira, comparando-o com a variedade Nanicão Jangada que lhe deu origem. Os materiais genéticos 'Nanicão Jangada'(controle) e o variante somaclonal representado pelas seleções 224 e 225 de um ensaio anterior, foram avaliados nos espaçamentos 2,0m X 2,0m (densidade 2500 plantas ha-1) e 3,0m X 2,0m (1666plantas ha-1), na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia - UNESP, Campus de Ilha Solteira-SP. O ensaio foi conduzido em blocos ao acaso com cinco repetições, com utilização de mudas micropropagadas, sob irrigação por gotejamento, no período de dezembro de 1998 a março de 2001, com avaliação dos dois primeiros ciclos de produção. Constatou-se efeito da densidade e do ciclo sobre a produção estimada de frutos sendo que no cultivo mais denso, a média foi de 81,25 t.ha-1 no primeiro ciclo de produção e 67,93 t.ha-1 no segundo ciclo. No cultivo de menor densidade a produção estimada no primeiro ciclo foi de 51,35 t.ha-1 e 44,08 t.ha-1 no segundo. As seleções do variante de porte baixo apresentaram menor altura da planta e mostraram-se relativamente mais precoces e com produção semelhante a cv. Nanicão Jangada no primeiro ciclo. No segundo ciclo houve uma queda na produção do bananal, com maior intensidade para a seleção 225 do variante.A dwarf somaclonal variant of banana was evaluated under two planting densities. It was compared with the cultivar "Nanicão Jangada", the original clone from which the variant derived. The genotypes 'Nanicão Jangada'(control) and the somaclone, represented by selections 224 and 225 from a previous experiment, were evaluated at spaced 2.0 m X 2.0 m (density of 2500 plants ha-1) and 3.0 m X 2.0 m (1666 plants ha-1) at the "Fazenda de Ensino e Pesquisa da Faculdade de Engenharia - UNESP", Campus de Ilha Solteira, SP. The experiment was conducted in randomized complete blocks with 5 replications, using micropropagated plants under irrigation from December 1998 to March 2001, with evaluation of the first two production cycles. Planting density and production cycle significantly affected estimated fruit yield, with the average in the densest cultivation being 81.25 t.ha-1 in the 1st cycle and 67.93 t.ha-1 in the second. In the lowest planting density cultivation, yield was estimated to be 51.35 t.ha-1 in the 1st cycle and 44.08 t.ha-1 in the 2nd. The dwarf somaclone selections were shorter and produced earlier with yield similar to cv. "Nanicão Jangada" in the first cycle. In the second cycle, there was a decrease in yield, especially for the somaclone variant selection.

Em fruticultura, existe hoje uma grande tendência de aumento da densidade de cultivo, procurando com isso uma maior produção por área. Pretendeu-se, neste trabalho, desenvolvido em Ilha Solteira-SP, estimar e analisar comparativamente o custo de produção e a lucratividade de bananeira-'Nanicão Jangada', sob duas densidades de cultivo: 1666 plantas (3,0mx2,0m) e 2500 plantas (2,0mx2,0m). Para o cálculo do custo, utilizou-se a estrutura do custo total de produção (CTP). Considerando os dois ciclos produtivos do bananal, o espaçamento de plantio mais adensado (com maior número de plantas por área) apresentou resultados econômicos mais satisfatórios que os obtidos para o cultivo menos adensado. A cultivar 'Nanicão Jangada' é uma alternativa de cultivo viável para a região de Ilha Solteira-SP.

Glyphosate resistance is conferred to soybean (Glycine max L. Merril) by incorporating a gene encoding a glyphosate-insensitive enzyme (CP4-EPSP synthase) that acts in the shikimate/chorismate pathway, an important metabolic route in the lignification process. The aim of this work was to investigate the root growth and lignin contents of susceptible (CD 201 and OC 14) and glyphosate-resistant (CD 214RR and CD 213RR) soybean cultivars. To this end, three-day-old seedlings were cultivated in half-strength Hoagland nutrient solution (pH 6.0) in a growth chamber (25°C, 12-h photoperiod, irradiance of 280 µmol m-2 s-1) for 24 to 96 hours. The results revealed that glyphosate-resistant (CD 213RR and CD 214RR) cultivars showed high root growth when compared to the conventional (OC-14 and CD 201) cultivars. CD 213RR showed high root lignin content and reduced root weight compared to the conventional (OC 14) cultivar, although CD 214RR and CD 201 did not follow the same trend. Based on these results, it is possible to conclude that (1) the different form of EPSP synthase encoded in RR soybean may interfere in phenylpropanoid pathway and further in lignin biosynthesis, and (2) other genetic characteristics inherent to each cultivar may affect roots lignin content in soybean seedlings since lignification in CD 214 RR was not affected of similar manner than cultivar CD 213 RR.

Background: Other tools for weed management should be considered in addition to the use of herbicides. In this context, the identification and use of allelopathic compounds deserves attention. Question: To quantify phenolic compounds and evaluate the allelopathic potential of extracts of Conyza sumatrensis on the germination of Bidens pilosa. Studied species: Conyza sumatrensis (Retz.) E.Walker, Bidens pilosa L. (Asteraceae) Study site: Palotina, state of Paraná, Brazil. Methods: The aqueous extracts were prepared with shoot and root portions of C. sumatrensis in concentrations: 0, 1, 5 and 10 %. Germination and germination speed index were evaluated. The total flavonoids and phenols of the tested extracts were also quantified. Results: With increasing concentrations of the extracts there was an increased inhibition of germination of B. pilosa and delays in the germination process. The extracts from the shoot of C. sumatrensis had a more expressive effect on seed germination when compared to the extracts obtained from the root. At concentration of 10 %, the extract from the shoot reduced in 83 % the percentage of germination. This may be related to the higher concentration of total flavonoids and phenols found. Conclusion: The allelopathic potential of C. sumatrensis plants can be considered since both shoot and root extracts inhibited and/or reduced the germination of B. pilosa.

Glyphosate resistance is conferred to soybean (Glycine max L. Merril) by incorporating a gene encoding a glyphosate-insensitive enzyme (CP4-EPSP synthase) that acts in the shikimate/chorismate pathway, an important metabolic route in the lignification process. The aim of this work was to investigate the root growth and lignin contents of susceptible (CD 201 and OC 14) and glyphosate-resistant (CD 214RR and CD 213RR) soybean cultivars. To this end, three-day-old seedlings were cultivated in half-strength Hoagland nutrient solution (pH 6.0) in a growth chamber (25‹C, 12-h photoperiod, irradiance of 280 ƒÊmol m-2 s-1) for 24 to 96 hours. The results revealed that glyphosate-resistant (CD 213RR and CD 214RR) cultivars showed high root growth when compared to the conventional (OC-14 and CD 201) cultivars. CD 213RR showed high root lignin content and reduced root weight compared to the conventional (OC 14) cultivar, although CD 214RR and CD 201 did not follow the same trend. Based on these results, it is possible to conclude that (1) the different form of EPSP synthase encoded in RR soybean may interfere in phenylpropanoid pathway and further in lignin biosynthesis, and (2) other genetic characteristics inherent to each cultivar may affect roots lignincontent in soybean seedlings since lignification in CD 214 RR was not affected of similar manner than cultivar CD 213 RR.A resistencia ao glifosato e conferida a soja (Glycine max L. Merrill) pela incorporacao de um gene que codifica a enzima CP4-EPSP sintase, uma variante da EPSP sintase, insensivel ao glifosato, que atua na via do chiquimato/corismato, importante rota metabolica envolvida na lignificacao. O objetivo deste trabalho foi o de investigar o crescimento e os teores de lignina nas raizes de cultivares de soja, suscetiveis (CD 201 e OC 14) e resistentes (CD 214RR e CD 213RR) ao glifosato. Para isso, plantulas com tres dias de desenvolvimento foram cultivadas em solucao nutritiva de Hoagland, meia-forca (pH 6,0), em camara de crescimento (25‹C, fotoperiodo de 12 h, irradiancia de 280 ƒÊmol m-2 s-1) de 24 a 96h. Os resultados revelaram que as cultivares resistentes ao glifosato (CD 213RR e CD 214RR) apresentaram elevado crescimento das raizes quando comparadas com as cultivares convencionais (OC-14 e CD 201). A cultivar CD 213RR apresentou altos teores de lignina e reduzido crescimento das raizes em comparacao com a cultivar convencional (OC 14). O mesmo nao foi observado nas cultivares CD 214RR e CD 201. Com base nos resultados, e possivel concluir que (1) uma forma diferente de EPSP sintase pode interferir na via de fenilpropanoides e, posteriormente, na sintese de lignina, e (2) outras caracteristicas geneticas inerentes a cada cultivar pode afetar os conteudos de lignina nas raizes, haja vista que a lignificacao na cultivar CD 214RR nao foi afetada de similar maneira que na cultivar CD 213RR.

A partir da comprovação por vários estudos que as sementes de Moringa (Moringa oleifera L.) apresentam a capacidade de clarificar e purificar água potencialmente fora de especificações para consumo humano. Objetivou-se com o presente projeto avaliar se a semente de moringa tem capacidade de purificar água residuária de curtume. Foi utilizada água residuária bruta, coletada antes das estações de tratamento de dois curtumes no município de Maringá, Paraná. As sementes de moringa foram obtidas nos municípios de Umuarama e Floraí, Paraná. As sementes foram retiradas do fruto antes do processo de deiscência e trituradas em meio de água destilada. O sistema foi realizado em sistema descontínuo de tratamento, utilizando vasos de 25litros, onde foram utilizados 15 litros de água residuárias de curtume. Foram feitos uma testemunha e três tratamentos com a mesma concentração 8,0 g L-1 variando a fração em função do tempo de 4, 8 e 12 horas. Foram avaliados os parâmetros: pH, nitrogênio amoniacal, turbidez, DBO e DQO. Os melhores resultados obtidos foram no parâmetro nitrogênio. = The evidence from several studies have indicated that the seeds of Moringa (Moringa oleifera L.) have the ability to clarify and purify water potentially out of specification for human consumption. The objective of this project was to evaluate whether the seeds of moringa are capable of purifying wastewater from tannery. Untreated wastewater was used, collected before entering the treatment plants of two tanneries in the city of Maringá, Paraná, Brazil. The moringa seeds were collected in the municipalities of Umuarama and Floraí, Paraná, Brazil. Seeds were removed from the fruit before dehiscence and crushed within distilled water. The system was carried out in batch processing, using 25-liter pots, and 15 liters of wastewater from the tannery. One control and three treatments were used. All groups contained the same concentration 8.0 g L-1 but were done in 4, 8 and 12 hours. The following parameters were evaluated: pH, ammonia nitrogen, turbidity, BOD and COD. The best results were obtained in the parameter nitrogen.

A partir da comprovação por vários estudos que as sementes de Moringa (Moringa oleifera L.) apresentam a capacidade de clarificar e purificar água potencialmente fora de especificações para consumo humano. Objetivou-se com o presente projeto avaliar se a semente de moringa tem capacidade de purificar água residuária de curtume. Foi utilizada água residuária bruta, coletada antes das estações de tratamento de dois curtumes no município de Maringá, Paraná. As sementes de moringa foram obtidas nos municípios de Umuarama e Floraí, Paraná. As sementes foram retiradas do fruto antes do processo de deiscência e trituradas em meio de água destilada. O sistema foi realizado em sistema descontínuo de tratamento, utilizando vasos de 25 litros, onde foram utilizados 15 litros de água residuárias de curtume. Foram feitos uma testemunha e três tratamentos com a mesma concentração 8,0g L-1 variando a fração em função do tempo de 4, 8 e 12 horas. Foram avaliados os parâmetros: pH, nitrogênio amoniacal, turbidez, DBO e DQO. Os melhores resultados obtidos foram no parâmetro nitrogênio.