Determination of soybean cultivar resistance to soybean cyst nematode with quantitative polymerase chain reaction

Heterodera glycines, the soybean cyst nematode, is the major pathogen of Glycine max (soybean). Effective management of this pathogen is contingent on the use of resistant cultivars, thus screening for resistant cultivars is essential. The purpose of this research was to develop a method to assess infection of soybean roots by H. glycines with real-time quantitative Polymerase Chain Reaction (qPCR), a prelude to differentiation of resistance levels in soybean cultivars. Two experiments were conducted. In the first one, a consistent inoculation method was developed using to provide active second-stage juveniles (J2). Two-day-old soybean roots were infested with 0 and 1000 J2/mL. Twenty-four hours after infestation, the roots were surface sterilized and DNA was extracted with the DNA FastKit (MP Biomedicals, Santa Ana, CA)). For the qPCR assay, primer pair for single copy gene HgSNO, which codes for a protein involved in the production of vitamin B6, was selected for H. glycines DNA amplification within soybean roots. In the second experiment, compatible Lee 74, incompatible Peking and cultivars with different levels of resistance to H. glycines were inoculated with 0 and 1,000 J2/seedlings. Twenty-four hours post inoculation they were transplanted into pasteurized soil. Subsequently they were harvested at 1, 7, 10, 14 and 21 days post inoculation for DNA extraction. With the qPCR assay, the time needed to differentiate highly resistant cultivars from the rest was reduced. Quantification of H. glycines infection by traditional means (numbers of females produced in 30 days) is a time-consuming practice; the qPCR method can replace the traditional one and improve precision in determining infection levels.

Microtuberización del cultivar de papa (Solanum tuberosum L.) Banba en biorreactores económicos de inmersión temporal

El trabajo se realizó en el laboratorio de cultivo de tejidos de la Universidad Nacional Agraria (UNA) de mayo a septiembre de 2015. El mismo pretende sentar las bases de la producción de semilla básica con un método innovador, al producir microtubérculos de papa del cultivar Banba en BEITs y determinar la mejor variante de medio de cultivo en la fase de multiplicación y microtuberización. Se buscaron las características morfológicas deseadas, mediante el efecto de cinco variantes de medios de cultivos (0.10 y 0.20 mg l -1 de GA3 con 0.5 y 1 mg l -1 de bencilaminopurina (BAP)). Posteriormente se utilizaron cinco variantes de medios con BAP para la etapa de microtuberización en BEIT con 3000 ml de medio de cultivo en condiciones de crecimiento de 20 ± 3 °C, 16 horas luz y 8 de oscuridad con intensidad de luz de 2000 lux. El ensayo se estableció en BCA unifactorial con tres repeticiones. Para determinar las diferencias estadísticas entre las medias de los tratamientos se realizó la prueba de medias de diferencia mínima significativa (LSD) de Fisher con (α = 0.05). En los medios de multiplicación para las características altura de planta y número de brotes axilares, presentó mejor desempeño el medio con 0.10 mg l -1 de GA3 y 0.50 de BAP. Para el número de entrenudos no hubo diferencias significativas y para el número de hojas la mejor respuesta se obtuvo con 0.10 mg l -1 de GA3 y 0.50 g l -1 de BAP. En microtuberización se obtuvieron buenos resultados en microtubérculos por planta, diámetro y longitud en el medio de cultivo con 1 mg l -1 de BAP y 11% de sacarosa, así como microtubérculos esféricos superiores a los 0,6 g de peso en 36%.

Características químicas do solo e desempenho de culturas após quatro anos de aplicações de cama de aviário em diferentes épocas e níveis

Due to the high supply and its attractive cost, the poultry litter has been used in the southwestern region of Parana to the improvement of soil fertility seeking greater production of grains and pastures. However, the use without technical knowledge can minimize the benefits of poultry litter or even cause undesirable effects on soil, environmental pollution and also productivity losses in the used crops. The objective of this study was to evaluate the influence of different times of poultry litter application, predating the winter crop, associated with increasing levels, about soil chemical properties, release of nutrients and crop performances in four consecutive years (2011-2014). In the first three years the experimental design was randomized blocks with a split plot system and four replications. In the main plots were tested four poultry litter application times preceding the wheat production: 0, 15, 30 and 45 days before sowing (DAS); in the subplots were applied four poultry litter levels (wet basis): 0, 4, 8 and 12 Mg ha-1. Last year one more subdivision of plots was done, evaluating the use or not of nitrogen in coverage in wheat, at a dose of 100 kg N ha-1. The wheat cultivar used in the four years was the BRS 220. In three years it was evaluated the residual effect on soybean production (cultivar - BMX Turbo RR) and in one year on the beans. The chemical soil attributes were evaluated at four depths 0-2,5cm, 2,5-5cm, 5-10cm and 10-20cm, and also the rate of decomposition and nutrient release of poultry litter and the crop productivity. The different times of application concerning the poultry litter had little influence on the studied variables, demonstrating that the producer does not need to have a specific date (before planting) to the application of poultry litter. Potassium was fully released 60 days after the allocation of litter bags into the field; for nitrogen and phosphorus the release was slower. The use of increasing levels of poultry litter increased the levels of various soil elements, highlighting the potassium which reached 20 cm deep in the second year of evaluation. The increase in pH and in the base saturation occurred only in the upper layers, while the phosphorus reached 10 cm deep in the third year of the study. It was observed increased pH and base saturation. The use of increasing doses of poultry litter contributed to the wheat plant nutrition, significantly increasing the weight of a thousand grains, and the grain yield of wheat in all the evaluated years; the nitrogen fertilization in coverage also had significant effect for the fourth evaluated year. Also there was a significant response from the residual effect of poultry litter for crops planted in summer for both soybeans and beans.

Assessing nut germination protocols for macadamia cultivar 'Beaumont'

A rapid rate and high percentage of macadamia nut germination, together with production of vigorous seedlings, are required by nurseries and breeding programs. Germination of nuts is typically protracted, however, and rarely reaches 100%. Many studies have been conducted into macadamia germination, but most have assessed percent germination only. This study investigated the effects of various treatments on percent germination, germination rate, and plant, shoot and root dry weights. The treatments tested were combinations of: (i) soaking or not soaking seeds in a dilute fungicide solution prior to planting; (ii) four different planting media; and (iii) leaving seed trays open or placing them inside clear plastic bags. For freshly harvested nuts, sowing in potting mix under clear plastic and without soaking produced the highest percent germination and germination rate, the largest shoots, and longest lateral roots.

Avaliação do potencial probiótico de leveduras isoladas de azeitonas de mesa da cultivar Negrinha de Freixo

Probióticos são definidos como microrganismos vivos, que quando administrados em quantidades adequadas, conferem benefícios à saúde do hospedeiro. Atualmente a pesquisa de microrganismos probióticos a partir da fermentação da azeitona tem-se centrado nas bactérias ácido-lácticas, sendo escassos os estudos envolvendo leveduras. No presente trabalho avaliou-se o potencial probiótico de estirpes de leveduras previamente isoladas durante o processo de fermentação natural de azeitona de mesada cultivar Negrinha de Freixo. Foram avaliadas 16 estirpes em relação à atividade enzimática (catalase, amilase, xilanase, protease e β-glucosidase); ao crescimento a 37ºC; ação inibitória frente a microrganismos patogénicos; capacidade de autoagregação; atividade antioxidante (utilizando o método de DPPH); e resistência ao aparelho digestivo humano, a partir de uma simulação in vitro da digestão gástrica e pancreática. Os resultados apresentados para a atividade enzimática indicaram que em alguns isolados foi detetado fraca atividade das enzimas protease, xilanase e amilase. Já uma atividade forte de lipase foi observada nas estirpes Pichia manshurica e Saccharomyces cerevisiae (15A e 15B). Para a enzima β-glucosidase, identificou-se atividade forte em Rhodotorula graminis, Rhodotorula glutinis, Candida norvegica, Pichia guilliermondii e Galactomyces reessii. Relativamente à capacidade de crescimento à temperatura corporal (37ºC), três estirpes (Saccharomyces cerevisiae 15B; Candida tropicalis 1A; e Pichia membranifaciens 29A) destacaram-se por apresentar maior taxa específica de crescimento. A capacidade bloqueadora dos radicais livres DPPH foi verificada em 10 estirpes, sendo as estirpes de S. cerevisiae as que mais se destacaram dentre as outras. As estirpes C. norvegica e G. reessii (34A) apresentaram capacidade antifúngica frente ao microrganismo patogénico Cryptococcus neoformans. Em relação à capacidade de autoagregação avaliada, as estirpes S. cerevisiae (15A), Candida tropicalis (1A) e C. norvegica (7A) apresentaram ao fim de 24 horas percentagens superiores a 80%. Relativamenteà resistência frente às condições presentes no trato gastrointestinal in vitro, a estirpe P. guilliermondii (25A), destacou-se dentre as demais, por apresentar maior capacidade de sobrevivência em todo o processo digestivo simulado. As estirpes Candida boidinii (37A) e S. cerevisiae (15A) apresentaram menor capacidade de sobrevivência nestas condições. Contudo, serão necessários testes adicionais para complementar estes resultados.

Para Ana Fernanda Olano, cultivar es el oficio perfecto para la eternidad

Fondo Margaritainés Restrepo

Análisis comparativo de la determinación del número de granos y rendimiento en la población argentina de alpiste y un cultivar semienano de trigo

p.1-19

Efeito do glifosate sobre a nodulação da soja cv. BRS-Valiosa RR.

A soja resistente ao glifosate (RR) é uma tecnologia que vem acrescentar mais uma ferramenta ao manejo de plantas daninhas para essa cultura, que possui a maior área plantada no país. Estudos buscando informações para o uso correto da soja transgênica na região de Campinas/SP são importantes devido ao uso cada vez mais freqüente desta prática agrícola em todo o Estado e no Brasil. O objetivo deste trabalho foi avaliar esta tecnologia na nodulação da soja cv. Valiosa RR em condições de casa de vegetação. Os tratamentos utilizados foram aplicações isoladas de Roundup Ready a 1,5, 2,0 e 3,0 L.ha-1; aplicações seqüenciais de Roundup Ready a 1,5/1,5; 2,0/1,5 e 2,0/1,5/1,5 L.ha-1, além de uma testemunha absoluta. O número e as biomassas fresca e seca dos nódulos foram determinados nos estádios R3 e R5. Apesar de terem sido observadas reduções em alguns dos parâmetros avaliados, estas foram não significativas.

Seletividade de herbicidas pré-emergentes em campos de produção de sementes de Paspalum regnellii CV. BRS Guará.

2015

Avaliação das características morfogênicas de capim-sudão BRS Estribo submetido a diferentes disponibilidades hídricas.

Avaliou-se o efeito de diferentes disponibilidades hídricas sobre as características morfogênicas de capim-sudão BRS Estribo.

Physical and chemical properties of starch and flour from different common bean (Phaseolus vulgaris L.) cultivar.

The physical, chemical and pasting properties of the flour and isolated starches from six different bean cultivars (Phaseolus vulgaris L.) were investigated in order to obtain information for application in new products. The protein and total starch contents of the bean flours ranged from 17.72 to 20.27% and from 39.68 to 43.78%, respectively. The bean starches had low amounts of proteins, lipids and ash and showed an amylose content ranging between 45.32 and 51.11% and absolute density values between 1.55 and 1.78 g.cm?3. The bean starch granules were round to oval with a smooth surface. Results viscoamylographic profiles of the starches and flours showed the possibility of selecting cultivars for specific applications according to these characteristics.

BRS ARAGUAIA: híbrido de melão amarelo, produtivo e saboroso.

Equipe técnica: Valter Rodrigues Oliveira, Leonardo Silva Boiteux, Agnaldo Donizete Ferreira de Carvalho, Ailton Reis, André Nepomuceno Dusi, Carlos Alberto Lopes, Celso Luiz Moretti, Geni Livtin Villas Bôas, Ítalo Moraes Rocha Guedes, Jadir Borges Pinheiro, João Maria Charchar, Leonora Mansur Mattos, Mirtes Freitas de Lima, Ronessa Bartolomeu de Souza, Werito Fernandes de Melo, Gláucia Salles Cortopassi Buso, Marco Antônio Ferreira, Fernando Antonio de Souza Aragão, Francisco das Chagas Vidal Neto, Waldelice Oliveira de Paiva, João Ribeiro Crisóstomo, Ricardo Elesbão Alves, José Luiz Mosca, Heloisa Almeida Cunha Figueiras, Antônio Apoliano dos Santos, Nivaldo Duardo Costa (CPATSA), Joston Simão de Assis (CPATSA), Rita de Cássia Souza Dias (CPATSA), José Amauri Buso, Marcos Coelho.

Avaliação dos teores de óleo de algodão colorido BRS Rubi e Safira em relação ao algodão tradicional.

2007

Batata BRS F63 (Camila): Produção de Material Básico com Alta Sanidade.

2015