Extraction methods and availability of phosphorus for soybean in soils from Parana State, Brazil

In studies on the evaluation of methodologies for the analysis of soil, phosphorus (P) has been the single most studied aspect, due to the complexity of this dynamic element in soil. However, these studies have been limited regarding soil conditions in Paranaa. The present study aimed to evaluate the efficiency of the Mehlich-1, Mehlich-3 and ion exchange resin methods in the evaluation of available P for soybean (Glycine max) in the soils of Paranaa State. Twelve soil samples collected from the upper 0-20 cm were planted with soybean for a period of 42 days in the greenhouse. The ability to extract soil P followed the order of decreasing average amount of extracted P: Mehlich-3 > resin > Mehlich-1. The correlation coefficients between the content of P extracted by Mehlich-1, Mehlich-3 and resin and the amount of P accumulated in the plants were 0.86, 0.90 and 0.93, respectively. Mehlich-1, Mehlich-3 and resin showed similar efficiency in the evaluation of P availability to plants and, under conditions of natural fertility and in soils that had received no application of poorly natural reactive phosphates, can be used to quantify the concentrations of P in the soils of Parana State.

Different timing of whitefly control and soybean yield

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Screening Botryosphaeria species for lipases: Production of lipase by Botryosphaeria ribis EC-01 grown on soybean oil and other carbon sources

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of soybean oil and Tween 80 on the production of botryosphaeran by Botryosphaeria rhodina MAMB-05

The addition of soybean oil and Tween 80 was evaluated with the objective of increasing the production of botryosphaeran, an exopolysaccharide (EPS) of the (1 -> 3 ;1 -> 6)-beta-D-glucan type produced by the fungus Botowsphaeria rhodina MAMB-05. Factorial design and analysis by response surface methodology was developed to select the main factors that would affect and enhance EPS production. The optimized culture conditions were: 40g l(-1) glucose with 10ml l(-1) soybean oil, and 4.5 ml l(-1) Tween 80, during 72h cultivation at 28 degrees C (180 rpm) and initial pH 5.7. The predicted result for botryosphaeran production was 8.22 +/- 1.36 g l(-1), and compared with the experimental value of 7.74 +/- 0.13 g l(-1) . Partial characterization of the botryosphaeran produced under the optimized conditions showed one type of polysaccharide with P-glycosidic linkages containing glucose as monosaccharide. (c) 2007 Elsevier Ltd. All rights reserved.

Soybean glycinin improves HDL-C and suppresses the effects of rosuvastatin on hypercholesterolemic rats

Background: This study was an investigation of the effects of ingesting a daily dose of isolated glycinin soy protein (11S globulin), in association with rosuvastatin, on the control of hypercholesterolemia in experimental animals.Methods: Male Wistar rats were kept in individual cages under appropriate controlled conditions of temperature, light and humidity. The animals were divided into five groups (n = 9): 1) standard (STD): fed on casein as protein source; 2) hypercholesterolemic (HC): STD plus 1% cholesterol and 0.5% cholic acid; 3) HC+11S: hypercholesterolemic + glycinin (300 mg/kg/day); 4) HC+ROS: hypercholesterolemic + rosuvastatin (10 mg/kg/day); 5) HC+11S+ROS: HC diet, the 11S protein and the drug in the doses given in (3) and (4). The protein and the drug were administered by gavage for 28 days. The results indicated that the addition of 1% cholesterol and 0.5% cholic acid induced hypercholesterolemia in the animals without interfering with their weight gain.Results: A single daily dose of glycinin contributed an additional 2.8% of dietary protein intake and demonstrated its functional role, particularly in raising HDL-C, decreasing triglycerides in the liver and improving the atherogenic index in animals exposed to a hypercholesterolemic diet.Conclusion: Most of the beneficial effects of the isolated treatments disappeared when the drug (rosuvastatin) and the protein (glycinin) were taken simultaneously. The association was shown not to interact additively, as noted in the plasma levels of total cholesterol and non-HDL cholesterol, and in the significant increase of cholesterol in the liver. Studies are in progress to identify the effects of peptides derived from the 11S globulin and their role in cholesterol metabolism.

Phosphate forms in plant and their internal buffering in five soybean cultivars

Diferenças inter e intra-específicas na habilidade de suportar períodos de estresse nutricional podem dever-se à capacidade de armazenar e liberar íons dos vacúolos, e, ou, à intensidade de retranslocação de nutrientes em tais condições. Neste trabalho, pretendeu-se avaliar diferenças varietais quanto ao tamanho do pool não-metabólico de Pi; velocidade de liberação do Pi previamente armazenado (VLPi), quando o P citoplasmático cai a um valor limite; capacidade de transportar Pi de regiões menos ativas para aquelas mais ativas metabolicamente e definir compartimentos que são preferencialmente fontes e os que são preferencialmente drenos para o Pi, em condições de absorção limitada de P. Avaliaram-se a produção de matéria seca e os teores internos de Pi, orgânico (Po) e total solúvel em ácido (Pts), de diferentes órgãos de plantas dos cultivares de soja (Glycine max L. Merrill) Santa Rosa, Uberaba, IAC8, Doko e UFV1, submetidos a oito dias de omissão do elemento. A VLPi foi estimada como tangente às equações obtidas para Pi como função do perído de omissão no ponto médio do período de omissão em que houve maior decréscimo em Pi (zero a quatro dias de omissão de P), t = dois dias, considerando-se que -deltaPi/deltat expressa a velocidade de liberação de Pi. A capacidade interna de tamponamento de Pi (CTIPi) foi calculada como o inverso da VLPi. O cultivar Santa Rosa apresentou maior capacidade de armazenar Pi, quando o suprimento externo foi alto, liberando-o mais intensamente sob condições de baixo suprimento de P que os cultivares IAC8 e UFV1. O cultivar Uberaba mostrou-se superior ao Doko em sua habilidade de armazenar e utilizar o Pi. Folhas superiores mostraram ser o principal dreno para o Pi armazenado em folhas medianas e inferiores, seguidas por raízes e caules. Raízes comportaram-se como fontes ou drenos para o Pi. Raízes e folhas superiores apresentaram maiores (VLPi) e menores valores de CTIPi que folhas medianas e folhas inferiores, sendo o caule o compartimento com menor VLPi e maior CTIPi. Dentre as variedades, as diferenças foram pequenas, destacando-se a maior VLPi e menor CTIPi do cultivar Santa Rosa. O cultivar Doko apresentou a menor VLPi e maior CTIPi, enquanto Uberaba, IAC8 e UFV1 ocuparam posição intermediária quanto a essas características.

Morphological and physiological alterations induced by lactofen in soybean leaves are reduced with nitric oxide

O lactofen é um herbicida difeniléter recomendado para controlar plantas daninhas de folhas largas em campos de soja (Glycine max) e seu mecanismo de ação é a inibição da protoporfirinogênio-IX oxidase (Protox), que atua na biossíntese de clorofilas. Essa inibição resulta em um acúmulo de protoporfirina-IX, o que leva à produção de espécies reativas de oxigênio (ROS), causando estresse oxidativo. Conseqüentemente, podem ocorrer manchas, enrugamento e queima das folhas, o que leva à paralisação temporária do crescimento da cultura. Porém, o óxido nítrico (NO) atua como um antioxidante na eliminação direta das ROS. Assim, o objetivo deste trabalho foi verificar, por meio de avaliações fitométricas e bioquímicas, o efeito protetor do NO em plantas de soja tratadas com o herbicida lactofen. Plantas de soja foram pré-tratadas com diferentes doses de Nitroprussiato de Sódio (SNP), substância doadora de NO, e então pulverizadas com 168 g a.i. ha-1 lactofen. O pré-tratamento com SNP foi benéfico, pois o NO reduziu os sintomas de injúria causados pelo lactofen nos folíolos jovens e manteve baixos teores de açúcares solúveis. Porém, o NO proporcionou crescimento mais lento das plantas. Desta forma, posteriores estudos são necessários para elucidar os mecanismos de ação do NO na sinalização do estresse promovido pelo lactofen na cultura da soja.

Genetic structure of populations of Rhizoctonia solani anastomosis group-1 IA from soybean in Brazil

The Basidiomycete fungus Rhizoctonia solani anastomosis group (AG)-1 IA is a major pathogen of soybean in Brazil, where the average yield losses have reached 30 to 60% in some states in Northern Brazil. No information is currently available concerning levels of genetic diversity and population structure for this pathogen in Brazil. A total of 232 isolates of R. solani AG1 IA were collected from five soybean fields in the most important soybean production areas in central-western, northern, and northeastern Brazil. These isolates were genotyped using 10 microsatellite loci. Most of the multilocus genotypes (MLGTs) were site-specific, with few MLGTs shared among populations. Significant population subdivision was evident. High levels of admixture were observed for populations from Mato Grosso and Tocantins. After removing admixed genotypes, three out of five field populations (Maranhao, Mato Grosso, and Tocantins), were in Hardy-Weinberg (HW) equilibrium, consistent with sexual recombination. HW and gametic disequilibrium were found for the remaining soybean-infecting populations. The findings of low genotypic diversity, departures from HW equilibrium, gametic disequilibrium, and high degree of population subdivision in these R. solani AG-1 IA populations from Brazil are consistent with predominantly asexual reproduction, short-distance dispersal of vegetative propagules (mycelium or sclerotia), and limited long-distance dispersal, possibly via contaminated seed. None of the soybean-infecting populations showed a reduction in population size (bottleneck effect). We detected asymmetric historical migration among the soybean-infecting populations, which could explain the observed levels of subdivision.

Divergence Between Sympatric Rice- and Soybean-Infecting Populations of Rhizoctonia solani Anastomosis Group-1 IA

Rhizoctonia solani anastomosis group (AG)-1 IA causes soybean foliar blighting (aerial blight) and rice sheath blight diseases. Although taxonomically related within the AG-1 complex, sister populations of R. solani AG-1 IA infecting Poaceae (rice) and Fabaceae (soybean) are genetically distinct based on internal transcribed spacer rDNA. However, there is Currently no information available regarding the extent of genetic differentiation and host specialization between rice- and soybean-infecting populations of R. solani AG-1 IA. We used 10 microsatellite loci to compare sympatric R. solani AG-1 IA populations infecting rice and soybeans in Louisiana and one allopatric rice-infecting population from Texas. None of the 154 multilocus genotypes found among the 223 isolates were shared among the three populations. Partitioning of genetic diversity showed significant differentiation among sympatric populations from different host Species (Phi(ST) = 0.39 to 0.41). Historical migration patterns between sympatric rice- and soybean-infecting populations from Louisiana were asymmetrical. Rice- and soybean-derived isolates of R. solani AG-1 IA were able to infect both rice and soybean, but were significantly more aggressive on their host of on-in, consistent with host specialization. The soybean-infecting Population from Louisiana was more clonal than the sympatric rice-infecting population. Most of the loci in the soybean-infecting populations were Out of Hardy-Weinberg equilibrium (HWE.), but the sympatric rice-infecting population from Louisiana was mainly in HWE. All populations presented evidence for a mixed reproductive system.

Inter-relation between soybean yield and soil compaction under degraded pasture in Brazilian Savannah

As pastagens cultivadas do Cerrado brasileiro são responsáveis pela metade da produtividade da carne bovina destinada à alimentação da população, enquanto as culturas agrícolas o são pela terça parte de sua produtividade de grãos, desempenhando importante papel econômico-financeiro para o país. Dessa forma, no ano agrícola 2005/2006, na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia de Ilha Solteira - FEIS/UNESP, foram estudadas a variabilidade e a dependência espacial entre atributos físicos do solo e a produtividade da soja, quando rotacionados após a pastagem degradada com Brachiaria, sobre um Latossolo Vermelho distroférrico. Também foram estudadas correlações lineares e espaciais entre esses atributos, apurando condições que proporcionassem aumento da produtividade agrícola. Para isso, na área com a referida pastagem instalou-se uma malha contendo 124 pontos amostrais, com espaçamentos de 10,0 x 10,0 e de 5,0 x 5,0 m entre eles, numa área total de 7.500 m². Dos pontos de vista linear e espacial, a elevada produtividade de grãos de soja pode ser explicada em razão do número de grãos por planta e da macroporosidade do solo. A alta variabilidade obtida na maioria dos atributos do solo denotou que a integração lavoura-pecuária é um sistema que proporciona heterogeneidade do ambiente físico do solo.

Soybean Oil and Beef Tallow in Starter Broiler Diets

The objective of this study was to determine the energy values of soybean oil (SBO) and tallow (T) combined in different ratios, and to evaluate their effects on the performance, body composition, and serum lipid levels of starter broilers. In experiment I, a digestibility trial was performed to determine the energy value of the SOB and T mixtures using 100 12 - to 21 -day-old broilers. In experiment II, 930 one-day-old broilers were used. Treatments consisted of the inclusion of 4% SBO and T inclusions at the following ratios: 0:100, 25:75, 50:50, 75:25, 100:0. Each treatment included six replicates. In experiment I, AME and AMEn linearly increased (P<0.01), as SBO participation in the mixture increased. In experiment II, the different lipid ratios quadratically influenced (P<0.01) body weight and weight gain at 21 days of age, increasing up to the ratio of 65.87:34.13. Serum lipids linearly decreased (P<0.05) as SOB inclusion in the diet increased. It was concluded that AME and AMEn of SBO and T at ratios of 0:100, 25:75, 50:50, 75:25, and 100:0 were 7.882 and 7.542, 8.384 and 8.076, 8.701 and 8.385, 8.801 and 8.727, and 9.478 and 9.271 kcal/kg, respectively. The best performance with no detrimental effect on carcass yield was obtained with the mixture of 75% SBO with 25% T. The highest dietary soybean oil level reduced serum lipid levels of 21-day-old broilers.

Replacing egg yolk with soybean lecithin in the cryopreservation of stallion semen

The objective of this study was to determine whether replacing the egg yolk with soybean lecithin in the Botu-Crio (R) cryodiluent would maintain the fertility of cryopreserved stallion sperm. Two experiments were performed to evaluate cell freezability. In experiment 1, sperm from 15 stallions were frozen in Botu-Crio (R) (BC) or Botu-Crio (R) which contained 45 g/L soybean lecithin (BCLS45) in place of the egg yolk. In experiment 2, we compared different concentrations of soybean lecithin: 0, 10.0, 12.5, 15.0, 17.5 and 20.0 g/L (BC, BCLS10, BCLS12.5, BCLS17.5 and BCLS20, respectively). In experiment 1, sperm frozen in BC and BCLS45 exhibited similar (P > 0.05) percentages of total motile sperm (61% and 61%, respectively); progressively motile sperm (27% and 27%, respectively) and sperm with intact plasma membranes (IMP; 53% and 57%, respectively). Similarly, sperm frozen in BC or BC containing any concentration of soybean lecithin maintained similar (P > 0.05) percentages of total motile sperm (61-68%) and progressively motile sperm (27-31%). In the first fertility trial, we used cryopreserved semen from a single stallion was inseminated into mares. The semen from the sperm that were frozen in BC diluent resulted in a higher fertility rate (66%, 16/24) compared to the sperm that were frozen in BCLS45 diluent (17%, 5/29; P < 0.01). Similarly, in a second fertility trial, the mares that were inseminated with the sperm that were frozen in BC diluent exhibited a higher fertility rate (66%, 16/24) compared to the mares that were inseminated with the sperm that were frozen in BCLS20 (40%, 10/25; Pc 0.05). Finally, in a third trial, the sperm that were frozen in BC resulted in a higher fertility rate in mares (75%, 18/24) compared to the sperm that were frozen in BCLS10 (41%, 10/24; P < 0.05). Although replacing the egg yolk in the BC cryodiluent with soybean lecithin provided similar laboratory results for stallion sperm, after cryopreservation, the sperm that was frozen with soybean lecithin in the diluent correlated with lower fertility rates. Based on these results, we concluded that the use of BCLS can be used as an alternative diluent for cryopreserving stallion sperm. However, the resulting reduced fertility rate is a matter of concern. Further studies are necessary to clarify the reasons for this decrease in fertility and to determine the optimal lecithin concentration for diluents to freeze stallion sperm. (C) 2011 Elsevier B.V. All rights reserved.