Amylose content and micromorphology of popcorn progenies with different popping expansion volumes / Teores de amilose e micromorfologia de progênies de milho-pipoca com diferentes volumes de expansão

ABSTRACT: Popcorn (Zea mays var. everta) has a higher commercial value than common maize, in addition to being a popular food among consumers. Today, there is a constant search for cultivars with superior performance for several traits of interest in the case of popcorn, yield and popping expansion. On this basis, this project proposes to characterize progenies of popcorn with different values ​​of expansion capacity regarding chemical composition and micromorphology. Kernels from the fifth cycle (C5) of intrapopulation recurrent selection were evaluated. The progenies were selected based on the popping expansion volume of their kernels. The kernels were quantified for amylose and analyzed for starch granule arrangement and pericarp thickness by scanning electron microscopy. Progenies with low popping expansion volume (0 and 7 mL g-1) showed amylose contents of 21.24 and 20.18%, respectively; a less compact endosperm, with individual starch granules interspaced with empty spaces; and pericarp thickness between 40.94 and 38.99 µm, respectively. By contrast, progenies with high popping expansion volume (30 and 35 mL g-1) showed amylose contents of 23.92 and 26.10%; a vitreous endosperm; more-compact starch granules without empty spaces in between; and pericarp thickness between 107.66 and 107.84 µm. Progenies with higher popping expansion volume exhibited a thicker pericarp, a high amylose percentage and a more-compact endosperm, whereas those with the lower expansion volumes showed a thinner pericarp, a lower amylose percentage and individual starch granules.

RESUMO: O milho-pipoca (Zea mays var. everta) tem um valor comercial mais elevado do que o milho comum e é um alimento popular entre os consumidores. Hoje, existe uma constante busca por cultivares com desempenho superior para os diversos caracteres de interesse, no caso da pipoca, produtividade e capacidade de expansão. O trabalho propõe caracterizar progênies de milho-pipoca com diferentes valores de capacidade de expansão quanto à composição química e micromorfologia. Foram estudados grãos do quinto ciclo (C5) de seleção recorrente intrapopulacional. As progênies foram selecionadas com base nos valores de capacidade de expansão de seus grãos. Os grãos foram quantificados para amilose e analisados quanto ao arranjo dos grânulos de amido e espessura do pericarpo por microscopia eletrônica de varredura. Progênies com baixa capacidade de expansão (0 e 7 mL g-1) apresentaram teor de amilose de 21,24 e 20,18% respectivamente; endosperma menos compacto, com grânulos de amido individualizados e intercalados com espaços vazios; e espessura do pericarpo medindo entre 40,94 e 38,99 µm, respectivamente. Por outro lado, progênies com alta capacidade de expansão (30 e 35 mL g-1) apresentaram teor de amilose de 23,92 e 26,10%, endosperma vítreo, sendo os grânulos de amido mais compactos e sem espaços vazios entre eles; e espessura do pericarpo medindo entre 107,66 e 107,84 µm. Progênies com altos valores de capacidade de expansão apresentam maior espessura de pericarpo, alta porcentagem de amilose e endosperma mais compactado, enquanto as com menores valores de expansão, apresentam menor espessura do pericarpo, menor porcentagem de amilose e grânulos de amido individualizados.

Propiedades funcionales in-vitro y efectos fisiológicos in-vivo sobre ratas Holtzman de dietas con nuevas fuentes de fibra / Functional properties in vitro and physiological effects in vivo of new sources of dietary fiber in Holtzman rats

RESUMEN El endospermo de semilla de tara (EST) y polvo de las hojas de Agave americana (HAA) fueron evaluados como nuevas fuentes de fibra dietética teniendo como referencia al salvado de trigo (ST). Mediante experimentos in vitro se determinaron las propiedades funcionales y con experimentos in vivo, en ratas Holtzman, los efectos fisiológicos de las dietas alimentadas con 6% de fuente de fibra. El EST tuvo 32,2% de solubilidad; 45,0 g/g de capacidad de absorción; 47,9 g/g retención de agua y 46 ml/g de hinchamiento; valores significativamente superior al ST (p< 0,01). En cambio, el HAA presentó 6,38 g/g de capacidad de adsorción del aceite respecto al 5,27 del ST (p< 0,01). La dieta con EST, tuvieron 8,76% de grasa fecal, valor que supera al ST (p< 0,01). Sin embargo, no hubo efecto sobre el peso corporal de las ratas. El HAA incrementó el volumen fecal y redujo de 14,9 a 10,4 h el tiempo de tránsito intestinal (p< 0,01). El endospermo de semilla de tara, retiene la grasa de la dieta y la elimina a través de las heces; en cambio, el polvo de las hojas de Agave americana, reduce el tiempo de tránsito intestinal.

ABSTRACT The endosperm of tara seeds (EST) and powder from the leaves of Agave americana (HAA) were evaluated as new sources of dietary fiber, using wheat bran (ST) as a reference. In vitro experiments were carried out to determine functional properties and in vivo experiments were used to determine the physiological effects of fed Holtzman rats with diets with 6% of each fiber source. Endosperm of tara had 32.2% solubility, 45.0 and 47.9 g/g absorption and water retention capacity, respectively, and 46 ml/g swelling, values significantly higher than wheat bran (p< 0.01). On the other hand, Agave had higher adsorption capacity of oil than wheat bran (6.38 g/g vs. 5.27 g/g; p< 0.01). Diets with endosperm of tara, were 8.76% of fecal fat, a value that exceeded that of wheat bran (p< 0.01); however, there was no effect on body weight of the rats. Agave increased fecal volume and reduced (p< 0.01) intestinal transit time from 14.9 to 10.4 h. Endosperm of tara retained and eliminated fat from the diet through the feces; on the other hand, the powder of Agave leaves reduced intestinal transit time.

Seed characters and their usefulness in the separation of Asteraceae species / Caracteres de sementes e sua utilidade na separação de espécies de Asteraceae

Studies on seed structure of Asteraceae have received little attention of botanists. Seed structure in Asteraceae is analyzed to evaluate the usefulness of characters in the separation of species through the analysis of nine weedy species. Seeds originate from anatropous, unitegmic and tenuinucellate ovules. The partial collapse of the developing seed coat is a common characteristic in the Asteraceae species studied. The testa consists of crushed and thin-walled cells in almost all of the species studied herein, except for Elephantopus mollis and Parthenium hysterophorus, which showed exotesta cells with U-shaped thickening. The analysis revealed high uniformity in seed characters.

Estudos da estrutura da semente de Asteraceae receberam pouca atenção de botânicos. A estrutura da semente de Asteraceae é examinada com a finalidade de avaliar a utilidade dos caracteres na separação de espécies, mediante a análise de nove espécies de plantas daninhas. As sementes são originárias de óvulos anátropos, unitegumentado e tenuinucelados. O colapso parcial do revestimento da semente em desenvolvimento é uma característica comum nas espécies estudadas de Asteraceae. A testa é composta por células colapsadas e de paredes finas em quase todas as espécies estudadas, com exceção de Elephantopus mollis e Parthenium hysterophorus, que demonstraram células da exotesta com espessamento em U. A análise revelou uma grande quantidade de uniformidade dos caracteres estudados das sementes.

Silagem de grãos úmidos de milho de textura dura ou macia em dietas com polpa cítrica para vacas em lactação / High moisture silage of hard or soft corn grain in citrus pulp diets for lactating cows

Avaliou-se o desempenho de vacas leiteiras que consumiram polpa cítrica e dois teores dietéticos de silagem de grão úmido de milho. Os tratamentos foram: milho de textura dura ou milho de textura macia ensilado na linha negra, em fatorial com 9% ou 18% de milho na dieta. O teor de polpa cítrica na dieta foi de 16,2% ou 25,6%, com alto e baixo milho, respectivamente. Doze vacas receberam os tratamentos em quadrados latinos 4x4. A produção diária de leite foi 27,9kg no milho duro e 28,8 no macio (P=0,19). Alto milho diminuiu o teor de gordura do leite de 3,38 para 3,26% (P=0,04) e aumentou o teor de proteína de 2,99 para 3,03% (P=0,05) e a eficiência alimentar de 1,50 para 1,57kg de leite/kg de consumo (P=0,03). Aumento no teor de milho induziu maior queda no pH ruminal na dieta com milho macio do que na dieta com milho duro (P=0,05 para a interação textura versus teor de milho). O milho macio aumentou o consumo diário de matéria orgânica digestível de 11,7 para 12,3kg (P=0,05). Os parâmetros digestivos sugerem que a ensilagem não eliminou totalmente o efeito da textura do endosperma sobre a digestibilidade do milho.

Lactating cow performance on diets containing citrus pulp and two levels of high moisture corn silage was evaluated. Treatments were: hard texture corn or soft texture corn ensiled at the black layer, with a 9% or 18% factorial corn in the diet. Dietary citrus pulp content was 16.2% or 25.6%, for high and low corn, respectively. Twelve cows received the treatments in 4x4 Latin Squares. Daily milk yield was 27.9kg for hard corn and 28.8 for soft (P=0.19). High corn decreased milk fat content from 3.38 to 3.26% (P=0.04), and increased protein content from 2.99 to 3.03% (P=0.05) and feed efficiency from 1.50 to 1.57kg of milk/kg of intake (P=0.03). The increase of corn content generated a greater decrease in ruminal pH in the soft corn diet than in the hard corn diet (P=0.05 for the interaction of texture versus corn content). Soft corn increased the daily intake of digestible organic matter from 11.7 to 12.3kg (P=0.05). Digestive parameters suggest that ensilaging did not totally eliminate the endosperm texture effect on corn digestibility.

Manufacture and influencing factors for artificial seeds of Dendrobium officinale / 中草药

Objective: To provide a new manufacturing method for the artificial seeds of Dendrobium officinale. Methods: The artificial seeds were manufactured by taking protocorms of D. officinale as the materials entrapped with the consideration of the effects of testa components and artificial endosperm on the germination and seedling of the artificial seeds. Results: The better conditions of the artificial seeds are manufactured in the fundamental artificial endosperm made by MS + 0.5 mg/L BA + 0.5 mg/L NAA +3 g/L AC + 30 g/L sodium alginate + 3 g/L chlorothalonil mixture reacted in 2% CaCl2 for 15 min; For the higher germination and seedling rate, 15 g/L cassava starch and 10 g/L water retaining agent can be added into the artificial endosperm components, respectively; For the higher germination rate, 10 g/L nano-SiO 2 (better planting rate) and 10 g/L Nano-TiO2 can be added into the artificial testa, respectively. The highest seedling rate was obtained by adding 10 g/L nano-SiO2. Conclusion: A manufacturing method of the artificial seeds of D. officinale has been established for the higher germination and seedling rates.

Maize (Zea Mays L) landraces from the southern region of Brazil: contamination by Fusarium sp, zearalenone, physical and mechanical characteristics of the kernels

This work had as objectives the study of the physical and mechanical characteristics of maize kernels in relation to the contamination by Fusarium sp and by zearalenone in twenty landraces of maize from the southern region of Brazil. From the analyzed samples, 60 percent has been considered to have a hard endosperm type and 40 percent an intermediary one. A correlation between the physical and mechanical variables was observed as an indication that the higher is the proportion of hard endosperm, more dense will be the kernel and more force for its rupture will be necessary. The level of contamination by Fusarium sp was between 5.5 and 24.75 percent among the analyzed grains, correlating positively with the flotation index, indicating that the landraces of maize with a softer endosperm can present a higher contamination by this genus. The presence of zearalenone was verified in 75 percent of the samples, in concentrations varying from 50 to 640 µg kg-1.

Este trabalho teve por objetivos verificar as características físicas, mecânicas, contaminação por Fusarium sp e por zearalenona e suas relações, em vinte variedades crioulas de milho da região sul do Brasil. Verificou-se que das amostras analisadas, 60 por cento foram consideradas como possuidoras de endosperma do tipo duro e 40 por cento com endosperma do tipo intermediário. As variáveis físicas e mecânicas se correlacionaram, indicando que quanto maior a proporção de endosperma vítreo, mais denso e maior a força necessária até a ruptura do grão. A contaminação por Fusarium sp esteve entre 5,5 por cento e 24,75 por cento nos grãos analisados, correlacionando-se positivamente com o índice de flotação, indicando que as variedades crioulas de milho com uma maior proporção de endosperma macio podem apresentar uma maior contaminação por Fusarium sp, sugerindo-se a utilização de variedades crioulas com a textura do endosperma predominantemente vítrea. A presença de zearalenona foi verificada em 75 por cento das amostras, em concentrações que variaram de 50 a 640 µg kg-1.

Cloning of high molecular weight gluten subunit promoter and study on its function in wheat

The aim of this work was to study the cloning and characterization of HMW-GS 1Dx2 promoter from Triticum aestivum. A 1050 bp partial promoter fragment including a putative TATA box and 5' encoding sequence of the gene was cloned by amplifying the upstream sequences using the nest-PCR with appropriate primers. The analysis of the promoter sequence against the PLACE (Plant cis-acting Regulatory DNA Elements) database showed the presence of certain putative endosperm-specific regulatory cis-elements in the sequence along with the TATA and CAAT boxes. The histochemical method detected the transient expressions of GUS in the seeds of wheat. The results showed that HMW-GS 1Dx2 promoter had the endosperm-specific transcription activity in the wheat seeds.

Valor nutritivo de grãos de sorgo com diferentes texturas do endosperma para leitões / Nutritive value of sorghum grains with different endosperm textures for piglets

Utilizaram-se 20 leitões machos castrados, com 28kg de peso, em ensaio biológico baseado em coleta total de fezes e de urina para a determinação dos valores de digestibilidade aparente da matéria seca (DAMS), de digestibilidade aparente da proteína bruta (DAPB), de energia digestível aparente (EDA) e de energia metabolizável aparente (EMA) de grãos de sorgo com diferentes texturas do endosperma. Os genótipos avaliados foram BR 007B (textura macia), BR 304 (textura intermediária) e SC 283 (textura dura). As dietas-teste foram compostas por 70 por cento de dieta referência, à base de milho e de farelo de soja, e por 30 por cento de grãos de sorgo. O experimento foi montado em esquema inteiramente ao acaso, com quatro tratamentos e cinco repetições. Os valores de DAMS, de DAPB, de EDA e de EMA, expressos na matéria seca, dos grãos do genótipo BR 007B foram 97,1 por cento, 89,7 por cento, 3.840kcal/kg e 3.685kcal/kg; os do genótipo BR 304 foram 92,0 por cento, 82,9 por cento, 3.645kcal/kg e 3.544kcal/kg; e os do genótipo SC 283 foram 83,3 por cento, 78,5 por cento, 3.078kcal/kg e 3.021 kcal/kg, respectivamente. Todas as quatro variáveis analisadas apresentaram valores mais altos (P<0,05) para o genótipo BR 007B em relação ao genótipo SC 283, demonstrando a influência negativa da textura do endosperma sobre o valor nutritivo dos grãos de sorgo para suínos.

Twenty hogs averaging 28kg were used in a biological assay based on total feces and urine collection method. The dry matter apparent digestibility (DMAD), the crude protein apparent digestibility (CPAD), the apparent digestible energy (ADE), and the apparent metabolizable energy (AME) values of the sorghum grains with different endosperm texture were calculated. The evaluated genotypes were: BR 007B (soft texture), BR 304 (intermediate texture), and SC 283 (hard texture). The test diets were composed by 70 percent of reference diet (based on corn and soybean meal) and 30 percent of sorghum grain. The experiment was a complete random design, with four treatments and five replicates. The DMAD, CPAD, ADE, and AME values, on dry matter basis, calculated for the genotype BR 007B were 97.1 percent, 89.7 percent, 3,840kcal/kg, and 3,685kcal/kg; for the genotype BR 304 they were 92.0 percent, 82.9 percent, 3,645kcal/kg, and 3,544kcal/kg; and for the genotype SC 283 they were 83.3 percent, 78.5 percent, 3,078kcal/kg, and 3,021kcal/kg, respectively. All analyzed variables presented higher values (P<0.05) for the genotype BR 007B in relation to the genotype SC 283, demonstrating the negative influence of the endosperm texture on the nutritional value of the sorghum grains for swine.

Storage sites in seeds of Caesalpinia echinata and C. ferrea (Leguminosae) with considerations on nutrients flow

The seeds of Caesalpinia echinata and C. ferrea behaved as typical endospermic seeds, despite their different morphological classification (exendospermic seeds were described for C. echinata and endospermic seeds for C. ferrea). Then, the aim of this work was to compare, under ultrastructural and histochemical terms, the nature of the storage substances and their accumulation sites, as well as the nutrient flow in seeds of these species. Cotyledons in C. echinata accumulate carbohydrates, lipids and proteins, which are mobilized from the outer to the inner parts as revealed by the position of plasmodesmata. Endosperm in C. ferrea accumulates carbohydrates and in C. echinata accumulates substances during the initial embryogenic phases. Such tissue develops a chalazal haustorium that is responsible for the transport of substances into the endosperm itself and from it into the embryo, confirmed by the presence of transference cells.

As sementes de Caesalpinia echinata e C. ferrea comportam-se como endospérmicas, apesar de descritas na literatura como exendospérmicas e endospérmicas, respectivamente. Desta forma, o objetivo deste trabalho foi comparar, em termos ultra-estrutural e histoquímico, a natureza das substâncias de reserva e seus tecidos acumuladores, bem como o fluxo de nutrientes nas sementes destas espécies. Os cotilédones em C. echinata acumulam carboidratos, lipídios e proteínas, mobilizados da periferia para o centro, como visto pelo posicionamento dos plasmodesmas. O endosperma em C. ferrea acumula carboidratos e lipídios, e em C. echinata, acumula substâncias nos estádios iniciais da embriogênese. Este tecido desenvolve um haustório calazal agressivo, que transporta substâncias para o endosperma propriamente dito e deste para o embrião, fato confirmado pela presença de células de transferência no endosperma.

Relationship between structural and biochemical characteristics and texture of corn grains

The texture of corn grains is a fundamental characteristic for the industry as well as for grain producers and processors. To further understand the mechanisms involved in grain hardness, contrasting corn cultivars for grain hardness and protein quality were evaluated. The cultivars were Cateto L237/67 (hard endosperm and low protein value), QPM BR 451 (semi-hard endosperm and high protein value); Bolivia-2 (floury endosperm and low protein value), and Opaque-2 (floury endosperm and high protein value). Evaluations were carried out at 10, 20, 30, 40, 50, and 60 days after pollination in developing corn grains and in the mature grain. In developing grains, evaluation consisted in the determination of the area, percentage of starch granules, distribution of starch granules, and protein bodies in the endosperm. In mature corn grains, the parameters evaluated were: density, percentage of total proteins, levels of lysine and tryptophan, and banding pattern of zeins. The results indicate that the higher physical resistance of corn grains from the cultivars analyzed is influenced by the high percentage of total proteins, high synthesis of 27-kDa zeins, presence of protein bodies, and perfect organization of starch granules in the endosperm, independent of their sizes.

Cloning and Expression Analysis of two Endosperm Promoters in Rice / 中国生物工程杂志

The cloning of promoter is important for studying the genetic engineering and the regulation of gene expression in plants. Two promoters Os772 and Os359, which are predicted to be highly expressed in the endosperm of rice from the EST database were cloned. After construction of the Os772∶∶GUS and Os359∶∶GUS expression vectors, they were transformed into rice. X-Gluc staining of transgenic plants showed that Os772 and Os359 can promote GUS gene expression in matured endosperm but not in root, stem, leaf and flower. This result indicates Os772 and Os359 are two rice endosperm-specific promoters.

Characterization of cytosolic phosphoglucoisomerase from immature wheat (Triticum aestivum L.) endosperm.

Phosphoglucoisomerase from cytosol of immature wheat endosperm was purified 650-fold by ammonium sulphate fractionation, isopropyl alcohol precipitation, DEAE-cellulose chromatography and gel filtration through Sepharose CL-6B. The enzyme, with a molecular weight of about 130,000, exhibited maximum activity at pH 8·1. It showed typical hyperbolic kinetics with both fructose 6-P and glucose 6-P with Km of 0·18 mM and 0·44mM respectively. On either side of the optimum pH, the enzyme had lower affinity for the substrates. Using glucose 6-P as the substrate, the equilibrium was reached at 27% fructose 6-P and 73% glucose 6-P with an equilibrium constant of 2·7. The ΔF' calculated from the apparent equilibrium constant was +597 cal mol–1 . The activation energy calculated from the Arrhenius plot was 5500 cal mol–1. The enzyme was completely inhibited by ribose 5-P, ribulose 5-P and 6-phosphogluconate, with Ki values of 0·17, 0·25 and 0·14 mM respectively. The probable role of the enzyme in starch biosynthesis is discussed.