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Sample records for grass panicum maximum

  1. Microbiological Quality of Panicum maximum Grass Silage with Addition of Lactobacillus sp. as Starter

    Science.gov (United States)

    Sumarsih, S.; Sulistiyanto, B.; Utama, C. S.

    2018-02-01

    The aim of the research was to evaluate microbiological quality of Panicum maximum grass silage with addition Lactobacillus sp as starter. The completely randomized design was been used on this research with 4 treaments and 3 replications. The treatments were P0 ( Panicum maximum grass silage without addition Lactobacillus sp ), P1 ( Panicum maximum grass silage with 2% addition Lactobacillus sp), P2 (Panicum maximum grass silage with 4% addition Lactobacillus sp) and P3 (Panicum maximum grass silage with 6% addition Lactobacillus sp).The parameters were microbial populations of Panicum maximum grass silage (total lactic acid bacteria, total bacteria, total fungi, and Coliform bacteria. The data obtained were analyzed variance (ANOVA) and further tests performed Duncan’s Multiple Areas. The population of lactic acid bacteria was higher (PMicrobiological quality of Panicum maximum grass silage with addition Lactobacillus sp was better than no addition Lactobacillus sp.

  2. Anti-nutrient components of guinea grass ( Panicum maximum ...

    African Journals Online (AJOL)

    This research was carried out in 2004 in the Department of Crop Science, University of Nigeria, Nsukka. The study investigated the anti-quality factors in Panicum maximum under different N-fertilizer application rates and cutting management. The experiment was a 4 × 4 factorial laid out in a randomized complete block ...

  3. Anti-nutrient components of guinea grass ( Panicum maximum ...

    African Journals Online (AJOL)

    Yomi

    2012-01-31

    Jan 31, 2012 ... The feeding value of any forage is a function of a number of characteristics of the species, including its availability, accessibility, nutrient availability ... Therefore, the present investigation was carried out to: (1) Evaluate the effect of cutting frequency on anti nutrient factors in P. maximum; (2) assess the effect ...

  4. De novo transcriptome assembly for the tropical grass Panicum maximum Jacq.

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    Guilherme Toledo-Silva

    Full Text Available Guinea grass (Panicum maximum Jacq. is a tropical African grass often used to feed beef cattle, which is an important economic activity in Brazil. Brazil is the leader in global meat exportation because of its exclusively pasture-raised bovine herds. Guinea grass also has potential uses in bioenergy production due to its elevated biomass generation through the C4 photosynthesis pathway. We generated approximately 13 Gb of data from Illumina sequencing of P. maximum leaves. Four different genotypes were sequenced, and the combined reads were assembled de novo into 38,192 unigenes and annotated; approximately 63% of the unigenes had homology to other proteins in the NCBI non-redundant protein database. Functional classification through COG (Clusters of Orthologous Groups, GO (Gene Ontology and KEGG (Kyoto Encyclopedia of Genes and Genomes analyses showed that the unigenes from Guinea grass leaves are involved in a wide range of biological processes and metabolic pathways, including C4 photosynthesis and lignocellulose generation, which are important for cattle grazing and bioenergy production. The most abundant transcripts were involved in carbon fixation, photosynthesis, RNA translation and heavy metal cellular homeostasis. Finally, we identified a number of potential molecular markers, including 5,035 microsatellites (SSRs and 346,456 single nucleotide polymorphisms (SNPs. To the best of our knowledge, this is the first study to characterize the complete leaf transcriptome of P. maximum using high-throughput sequencing. The biological information provided here will aid in gene expression studies and marker-assisted selection-based breeding research in tropical grasses.

  5. Producción de semilla de guinea (Panicum maximum Jacq. en un sistema intensivo de ceba de ganado vacuno Seed production of Guinea grass (Panicum maximum Jacq. in an intensive cattle fattening system

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    G Oquend

    2008-09-01

    Full Text Available En un suelo Pardo sialítico del subtipo Cambisol cálcico, localizado en la Empresa Pecuaria «Calixto García», en la provincia de Holguín, se estudio la producción de semilla de guinea (Panicum maximum Jacq. en un sistema intensivo de ceba de ganado vacuno, en condiciones de riego. Los tratamientos fueron cinco varieda­des del pasto guinea: A Común; B Likoni; C Mombasa; D Tanzania; y E Tobiatá. Los siguientes métodos se consideraron a su vez como subtratamientos: 1 Siembra con semilla gámica; 2 Plantación por macollas; y 3 Por vía de trasplante. La carga se mantuvo ajustada a 2 UGM/ha. En la producción de semillas existieron interacciones favorables entre los métodos de siembra y las variedades: semilla gámica-guinea Likoni; maco­lla-guinea Mombasa, Tanzania y Tobiatá; trasplante-guinea Común. En todo el sistema de explotación se obtuvo un aporte adicional superior a los $1 000/ha por concepto de producción de semilla, sin afectar la producción animal, en la que se obtuvieron ganancias superiores a los 800 g/animal/día y producciones pro­medio de 46 212 t de carne en pie por ciclo de ceba. Se considera factible la producción de semilla del pasto guinea en sistemas intensivos de ceba de ganado vacuno.On a sialitic Brown soil of the calcic Cambisol subtype, located at the «Calixto García» Livestock Production Enterprise, in the Holguín province, the production of Guinea grass (Panicum maximum Jacq. was studied in an intensive cattle fattening system, with irrigation. The treatments were five varieties of Guinea grass: A Common; B Likoni; C Mombasa; D Tanzania; and E Tobiatá. The following methods were considered, in turn, sub-treatments: 1 Seeding with gamic seed; 2 Planting with tillers; and 3 Transplanting. The stocking rate remained adjusted at 2 animals/ha. In seed production there were favorable interactions between the planting methods and the varieties: gamic seed-Guinea grass Likoni; tiller-Guinea grass

  6. Aislamiento e identificación de cepas de Azospirillum sp. en pasto guinea (Panicum maximum Jacq. del Valle del Cesar Isolation and identification of Azospirillum sp. in Guinea grass (Panicum maximum Jacq. of the Valle del Cesar

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    Diana M Cárdenas

    2010-09-01

    Full Text Available Se evaluó el efecto de factores ambientales del Valle del Cesar y el manejo agronómico del pasto guinea (Panicum maximum Jacq., sobre la población bacteriana del género Azospirillum en medios de cultivo semisólidos NFb y LGI, para lo cual se utilizó un diseño experimental en parcelas divididas con un arreglo factorial de 2 (épocas climáticas: lluvia y sequía x 2 (manejos agronómicos: agroecólogico y extractivo x 3 (muestras analizadas: suelo rizosférico, raíces y hojas. Los resultados no revelaron diferencias estadísticas significativas, lo que indica que esta bacteria puede mantener su población en condiciones de estrés por diferentes mecanismos fisiológicos. A partir de estas muestras se obtuvieron 16 aislamientos pertenecientes al género Azospirillum, a los cuales se les evaluó su actividad de reducción de acetileno como indicador de la fijación biológica de nitrógeno y su capacidad en la producción de compuestos indólicos como promotores del crecimiento vegetal. Se seleccionaron las cepas SRGM2, SRGM3 y SRGM4 obtenidas de muestras de suelo rizosférico de pasto guinea de la Estación Experimental Motilonia de Corpoica, municipio Agustín Codazzi, departamento del Cesar. Estos aislamientos se caracterizaron molecularmente por el gen 16S rRNA y según el análisis BLAST en la base de datos del GenBank y presentaron 93% de similitud con A. lipoferum (SRGM2 y SRGM3 y 94% con A. brasilense (SRGM4.The effect of environmental factors of the Valle del Cesar and the agronomic management of Guinea grass (Panicum maximum Jacq., on the bacterial population of the Azospirillum genus in semisolid NFb and LGI culture media was evaluated, for which an experimental design was used in divided plots with a 2 (climatic seasons: rainy and dry x 2 (agronomic managements: agroecological and extractive x 3 (analyzed samples: rhizospheric soil, roots and leaves factorial arrangement. The results did not reveal significant statistical

  7. Molecular markers linked to apomixis in Panicum maximum Jacq ...

    African Journals Online (AJOL)

    Panicum maximum Jacq. is an important forage grass of African origin largely used in the tropics. The genetic breeding of this species is based on the hybridization of sexual and apomictic genotypes and selection of apomictic F1 hybrids. The objective of this work was to identify molecular markers linked to apomixis in P.

  8. Estruturas silicosas na gramínea Panicum maximum

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    Pedro Fontana Junior

    1957-05-01

    Full Text Available The silica structure of the grass Panicum maximum were studied by electron and phase contrast microscopy. Several interesting kinds of silica formation (spiklets were found. The most ineresting structures ressembels the "Schaumstruktur" found by HELMCKE in diatoms. Another interesting structure was described in the "silica cells" and a detailed study of the mophology of some different kinds of spiklets was made.

  9. Effects of light intensity on growth, anatomy and forage quality of two tropical grasses (Brachiaria brizantha and Panicum maximum var. trichoglume).

    NARCIS (Netherlands)

    Deinum, B.; Sulastri, R.D.; Zeinab, M.H.J.; Maassen, A.

    1996-01-01

    Effects of light intensity on growth, histology and anatomy, and nutritive value were studied in seedlings of two shade tolerant species: Brachiaria brizantha and Panicum maximum var. trichoglume. They were studied under greenhouse conditions in pots with sandy soil and sufficient N and cut after a

  10. Strategic control of Rhipicephalus (Boophilus) microplus infestation on beef cattle grazed in Panicum maximum grasses in a subtropical semi-arid region of Argentina.

    Science.gov (United States)

    Morel, Nicolás; Signorini, Marcelo L; Mangold, Atilio J; Guglielmone, Alberto A; Nava, Santiago

    2017-09-01

    The aim of this work was to test the efficacy of strategic control methods of Rhipicephalus microplus infestation on beef cattle grazed in Panicum maximum grasses in northwestern Argentina. Also, an analysis to discern how the R. microplus population was distributed amongst cattle was also performed to determine if partial selective treatment or cull the small proportion of more heavily infested animals are feasible options to control this tick. The strategic scheme of treatments was designed to act on the small 1st generation of R. microplus in early spring and prevent in that way the appearance of the annual peak of abundance of R. microplus in summer and autumn. Animals of the group 1 were treated with ivermectin 3.15% on day 0 (25th September 2015), with fluazuron on day 32 (27th October 2015) and with fipronil on day 75 (9th December 2015). Animals of group 2 formed the control group. The overall effect of the treatments was positively significant. The number of ticks observed on the control group was significantly higher than the number of ticks observed on the treated group in all post-treatment counts (Pstrategic control method evaluated during this study provides a remarkable overall effect against R. microplus because it significantly reduces the tick infestation on cattle with only three applications of acaricides in one-year period. The analyses of tick distribution amongst cattle suggest that partial selective treatment and culling do not represent feasible methods to control R. microplus infestation on cattle. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Molecular markers linked to apomixis in Panicum maximum Jacq.

    African Journals Online (AJOL)

    SAM

    2014-05-28

    May 28, 2014 ... Panicum maximum Jacq. is an important forage grass of African origin largely used in the tropics. The genetic breeding of this ... Pastures play an important role in the national economy of most countries in the tropics .... final volume of 25 µL, using, 1xTaq DNA polymerase buffer. (Invitrogen); 1.5 mM MgCl2.

  12. The Genetics of Biofuel Traits in Panicum Grasses: Developing a Model System with Diploid Panicum Hallii

    Energy Technology Data Exchange (ETDEWEB)

    Juenger, Thomas [Univ. of Texas, Austin, TX (United States). Dept. of Integrative Biology; Wolfrum, Ed [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-07-31

    Our DOE funded project focused on characterizing natural variation in C4 perennial grasses including switchgrass (Panicum virgatum) and Hall’s panicgrass (Panicum hallii). The main theme of our project was to better understand traits linked with plant performance and that impact the utility of plant biomass as a biofuel feedstock. In addition, our project developed tools and resources for studying genetic variation in Panicum hallii. Our project successfully screened both Panicum virgatum and Panicum hallii diverse natural collections for a host of phenotypes, developed genetic mapping populations for both species, completed genetic mapping for biofuel related traits, and helped in the development of genomic resources of Panicum hallii. Together, these studies have improved our understanding of the role of genetic and environmental factors in impacting plant performance. This information, along with new tools, will help foster the improvement of perennial grasses for feedstock applications.

  13. Effect of concentrate supplementation during pre-kidding on the productive and reproductive performance of goats raised on Guinea grass (Panicum maximum cv. Tobiatã pasture

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    Raquel Ornelas Marques

    2016-06-01

    Full Text Available Sixty goats (20 Alpine, 18 Anglo-Nubian, and 22 crossbred Boer, with average body weight 49.33 ± 1.41 kg, were raised on Panicum maximum cv. Tobiatã pasture with two different levels of concentrate supplementation, 300 (SL30 and 600 g kg-1 (SL60 of the daily requirements, and evaluated from the pre-mating season until an average of 110 days of lactation. Milk controls were performed every 14 days. The following milk production curve parameters were estimated: time to reach peak milk production (TP, peak milk production (PP and milk production during the first 110 days of lactation (MP. The following milk components were determined: fat, protein, lactose, total solids (TS, defatted dry extract (DDE, urea nitrogen (UN concentrations, and somatic cell count (SCC. Goat prolificacy and birth weight of the kids were also determined. Breed affected the lactation curve, with Alpine and Anglo- Nubian goats presenting higher TP, PP, and MP. Protein, TS, and DDE concentrations were also affected by breed, being higher for crossbred Boer goats. Milk fat, lactose concentrations, and the log of SCC were affected by the concentrate supplementation level, being higher for SL30, as well as by the breed, with crossbred Boer goats presenting higher fat concentrations and log of SCC, and crossbred Boer and Alpine goats presenting higher lactose concentrations. UN was affected by the stage of lactation. Prolificacy and birth weight were affected by breed and concentrate supplementation level, being higher for Anglo-Nubian and crossbred Boer goats with SL60. Kids from single births presented higher birth weights. The Anglo-Nubian breed presented good milk production and the best body condition, which might indicate the effectiveness of this production system, SL60 supplementation resulted in higher birth weight and prolificacy.

  14. Densidade e qualidade dos estratos de forragem do capim Tanzânia (Panicum maximum Jacq. Cv. Tanzânia-1 manejado em diferentes alturas, sob pastejo Density bulk and quality of Tanzania grass layers (Panicum maximum Jacq.cv. Tanzania-1, at different heights in grazing

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    Geraldo Tadeu dos Santos

    2001-05-01

    Full Text Available O objetivo do trabalho foi avaliar o efeito de diferentes alturas (24; 26; 43; 45; 52; 62; 73 e 78 cm do pasto sobre a qualidade de forragem e estrutura do perfil do capim-Tanzânia, (Panicum maximum Jacq. cv. Tanzânia – 1 (Poaceae. Foram utilizados novilhos da raça Nelore sob pastejo com carga animal variável, por meio da técnica put and take. O delineamento experimental utilizado foi inteiramente casualizado, com duas repetições. A densidade de matéria seca total (DMT aumentou com o avanço no período experimental, enquanto a densidade de matéria seca de lâminas (DML não foi influenciada pelo período e pela altura do pasto. O estrato superior da pastagem foi a porção de maior qualidade, apresentando maior DML e maior teor de PB. Os estratos inferiores apresentaram menor qualidade, devido à maior DMT e menor DML, acarretando em maiores valores de FDA e FDN e menores teores de PB. O conteúdo de minerais das lâminas foi superior aos colmos, mantendo-se inalterado com relação aos estratos da pastagem.The effect of different sward heights (24; 26; 43; 45; 52; 62; 73 and 78 cm on forage quality and profile structure Tanzania grass, Panicum maximum Jacq. cv. Tanzania – 1 (Poaceae is provided. Nelore steers were used in grazing at variable stocking rates with put and take technique. The experimental design was completely randomized, with two replications. Total dry matter bulk densitity (TDMD increased during experimental period, while the leaf blade dry matter bulk density (LDMD was not influenced by period on by sward height. The upper layers had the best quality with higher LDMD and CP levels. Lower layers had the worst quality, due the higher TDMD and lower LDMD. This fact caused higher ADF and NDF levels and lower CP levels. Leaf blade mineral content was higher than that of stem, and remained unaltered in relation to the different layers.

  15. Genotypic value in hybrid progenies of Panicum maximum Jacq.

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    Thiago Gomes dos Santos Braz

    Full Text Available ABSTRACT: Genetic breeding of forage plants has increasingly contributed to the release of more productive plants. In this regard, evaluating the genotypic value is essential when aiming to rank genotypes based on the mean free of environmental factors. Therefore, this study aimed to predict the genotypic value of agronomic and nutritive value characters of three progenies of Panicum maximum. Hybrids were evaluated in a clonal test in an incomplete-randomized design with three treatments (progenies 1, 2, and 3 and two replications (clones. Six harvests were performed at 25cm from the ground level throughout one year. Progeny 2 provided better results for total and leaf dry mass yield, regrowth, and height, and lower incidence of leaf spot. Progenies 1 and 3 had a better response for qualitative characters such as higher crude protein and digestibility and lower lignin and fiber content. Hybrid progenies of P. maximum have forage characters of interest for breeding, and when using ‘Mombaça’ grass as parents, the progeny stands out for leaf production and resistance to leaf spot and for ‘Tanzania’ grass as parent has resulted in better forage quality.

  16. Composição química do capim-Mombaça (Panicum maximum Jacq. cv. Mombaça adubado com diferentes fontes de fósforo sob pastejo = Chemical composition of Mombaça grass (Panicum maximum Jacq. cv. Mombaça fertilized with different phosphorus on grazing

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    Fábio Jacobs Dias

    2007-01-01

    Full Text Available O objetivo foi avaliar a composição química do Panicum maximum Jacq. cv. Mombaça, adubado com 140 kg ha-1 de P2O5 com diferentes fontes de fósforo, sob pastejo, no período de dezembro de 2002 a abril de 2003, com intervalo de coleta a cada 28 dias. Tratamentos: 1- termofosfato magnesiano YoorinÒ; 2-fosfato natural GafsaÒ; 3-superfosfato simples + superfosfato triplo (SS + ST; e 4-testemunha. Os teores de proteína bruta na lâmina foliar (PBf e colmo (PBc, nitrogênio insolúvel em detergente ácido (NIDA, fibra em detergente neutro (FDN, fibra em detergente ácido (FDA, celulose (CEL, hemicelulose (HCEL, lignina (LIG, extrato etéreo (EE, cálcio (Ca, fósforo (P, cinzas e carboidratos não-estruturais (CNE, não foram influenciados pela adubação fosfatada. As variáveis PBc, FDNf, FDNc, LIGf, LIGc, CELf, CELc, NIDAf, EEf, EEc, Caf, Cac, Pf, Pc, CINZAc, CNEc, apresentaram efeito do período de coleta. Não ocorreu diferença nacomposição química da forragem do capim-Mombaça em função das fontes de fósforo utilizadas na adubação da pastagem. As variações qualitativas foram de baixa magnitude.This study aimed to evaluate the chemical composition of Panicum maximum Jacq. cv. Mombaça. Grassland was fertilized with 140 kg ha-1 of P2O5 from different phosphorus sources on grazing, in December, 2002, until April, 2003, with a collection interval of every 28 days. Treatments: 1-YoorinÒ magnesium thermophosphate; 2-GafsaÒ natural phosphate; 3-simple superphosphate + triple superphosphate (SS + TS and 4-control. Leaf (lCP and stem (sCP crude protein, acid detergent fiber nitrogen (ADFN, neutral detergent fiber (NDF, acid detergent fiber (ADF, cellulose (CEL, hemicellulose (HEM, lignin (LIG, ether extract (EE, calcium (Ca, phosphorus (P, ash (A and non-structural carbohydrates (NSC were not influenced by phosphated fertilization. The variables sCP, lNDF, sNDF, sLIG, lLIG, sCEL, lCEL, lADFN, sEE, lEE, lCa, sCa, lP, sP, sA and s

  17. NÍVEIS DE CALAGEM E FONTES DE FÓSFORO NA PRODUÇÃO DO CAPIM TANZÂNIA (Panicum maximum Jacq. cv. Tanzânia EFFECTS OF LIMING LEVELS AND PHOSPHORUS SOURCES ON TANZANIA GRASS YIELDS (Panicum maximum Jacq. cv. Tanzania

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    Luiz Augusto Fonseca Magalhães

    2007-09-01

    dry matter production of Tanzania grass (Panicum maximum Jacq. cv. Tanzania. The treatments were divided into groups 1 (G1 and 2 (G2. G1 evaluated three liming levels - no liming and liming to reach 30% and 60% base saturation (0, 1.12, and 2.64 t/ha, respectively – and three phosphorus sources – single superphosphate, Yoorin thermophosphate and Arad hyperphosphate. G2 evaluated the same liming levels and five phosphorus levels – 0, 30, 60, 120, and 240 kg/ha of P. In G1 no interactions were observed between phosphorus sources and liming, nor were liming effects. Significant differences were found for phosphorus sources: grass yield was higher under single superphosphate than under Yoorin thermophosphate or Arad hyperphosphate. Dry matter production in G2 didn't differ between liming levels and no interactions were observed between phosphorus and liming levels. However, there were significant differences among phosphorus levels, with maximum dry matter production for 172.8 kg/ha of P. This result confirms the importance of phosphorus fertilization to achieve high yields in Brazilian soils.

    KEY-WORDS: Phosphorus; liming; forages; tanzania grass.

  18. The regulation of starch accumulation in Panicum maximum Jacq ...

    African Journals Online (AJOL)

    ... decrease the starch level. These observations are discussed in relation to the photosynthetic characteristics of P. maximum. Keywords: accumulation; botany; carbon assimilation; co2 fixation; growth conditions; mesophyll; metabolites; nitrogen; nitrogen levels; nitrogen supply; panicum maximum; plant physiology; starch; ...

  19. Microelement contents of two Panicum maximum varieties as ...

    African Journals Online (AJOL)

    A study was carried out to determine the influence of variety, manure type and season on the micro mineral content of two P. maximum varieties. The trial included: two Panicum varieties (Local and Ntchisi), three manure types (cattle dung, swine dung and poultry droppings) plus control (No manure) and two seasons (rainy ...

  20. The regulation of starch accumulation in Panicum maximum Jacq ...

    African Journals Online (AJOL)

    Electron microscopic studies of Panicum maximum (PCK C4 photosynthetic type) when grown under controlled growth conditions as low nutrient nitrogen (20 ppm N, KNO3) showed interesting second order bundle sheath cell organisation: the cells were several times bigger than the mesophyll cells and were packed with ...

  1. Performance of weaner rabbits fed Panicum maximum, Centrosema ...

    African Journals Online (AJOL)

    Sixteen Crossbred Weaner rabbits aged eight weeks made up of 8 males and 8 females with initial average weight of 650 ± 21.76 g were subjected to four dietary treatments namely Panicum maximum plus Poultry growers mash (T1), Centrosema pubescens plus Poultry growers mash (T2) Sida acuta plus Poultry growers ...

  2. Morfogênese de cultivares de Panicum maximum jacq. Morphogenesis of Panicum maximum jacq. cultivars

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    Carlos Augusto Miranda Gomide

    2000-04-01

    Full Text Available Quatro cultivares de Panicum maximum, Mombaça, Tanzânia, Vencedor e Centenário, foram cultivados em vasos, sob cobertura plástica transparente, para estudo da dinâmica do crescimento de folhas e perfilhos, em dois tipos de perfilho, o principal e o primário, e dois crescimentos, o de estabelecimento, logo após a emergência das plântulas, e o de rebrota, após corte, a 8 cm do solo, aos 21 dias. Os tratamentos foram estudados, em arranjo fatorial 4 x 2 x 2, segundo delineamento de blocos completamente casualizados com quatro repetições. O comprimento da lâmina foliar cresceu com o nível de inserção até a folha de número 9 ou 10, tornando-se menor nas folhas subseqüentes. O perfilhamento teve início na segunda semana de idade e se estendeu até 22 dias de idade, quando o número de perfilhos por planta se estabilizou. O cultivar Tanzânia apresentou maior número de perfilhos por planta (15, enquanto em Mombaça e Vencedor foram observados apenas 10 perfilhos. Maiores taxas de aparecimento e alongamento de folhas foram observadas durante o crescimento de estabelecimento. Em ambos os crescimentos, o cultivar Vencedor exibiu a maior taxa de aparecimento de folhas. O número médio de folhas verdes por perfilho estabilizou-se em 6,5 no cultivar Vencedor e 3,5 nos demais cultivares, no crescimento de rebrota, em que a vida útil das folhas foi de 29 dias para o cultivar Centenário e 36 dias para os demais.Four cultivars of Panicum maximum: Mombaça, Tanzânia, Centenário and Vencedor were grown in pots, under a transparent plastic cover, to evaluate the dynamic of leaf and tillers growth. Two growths, the establishment and the aftermath, after clipping at the age of 21 days, and two types of tiller, main and primary tillers, were studied. A completely randomized design with four replicates was used to compare the treatments resulting from a 4 x 2 x 2 factorial arrangement. The leaf blade length increased with insertion level until

  3. Efeito do manejo sobre a produção e composição química de perfilhos do capim-colonião (Panicum maximum Jacq. Effect of management on the chemical composition and tillers production of colonião grass (Panicum maximum Jacq.

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    Jane Maria Bertocco Ezequiel

    2000-12-01

    Full Text Available O experimento foi conduzido com o objetivo de verificar os efeitos das freqüências de corte de 28, 35 e 42 dias, obtidas em dezembro, janeiro e fevereiro, cortadas rente a 15 cm e a 30 cm do solo, sobre a produção e composição química de perfilhos do capim-colonião. A área experimental foi adubada na semeadura e por ocasião dos cortes de uniformização. Verificou-se que a produção de MS foi o principal fator da produção de nutrientes por área. Os teores de PB dos perfilhos apresentaram comportamento não-linear com o avanço da idade e diminuíram sensivelmente a baixas alturas e altas freqüências de corte. Os teores de FDA dos perfilhos variaram pouco entre as idades de 28 e 42 dias. Concluiu-se que o melhor manejo do capim-colonião seria o corte a cada 42 dias e a 15 cm do solo.The effects of cutting frequency of 28, 35 and 42 days, performed in December, January and February at 0 cm, 15 cm and 30 cm from the ground on the chemical composition and tiller production of Panicum maximum Jacq were assayed. The experimental area was fertilized during the sowing, at uniform cuttings. Dry matter yield was the main factor affecting the nutrients production by area. The crude protein content of tillers showed no linear response to the cutting interval and sensitively decrease at low cutting height and high cutting frequency. The ADF concentrations of tillers exhibited small variation within the interval of growth period studied of 28 to 42 days. The best management for Panicum maximum could be at 42 days cutting frequency at 15 cm from the ground.

  4. Avaliação de métodos de amostragem em pastagens de capim-elefante (Pennisetum purpureum, Schum e capim-mombaça (Panicum maximum, Jacq sob pastejo rotacionado Evaluation of sampling methods for elephant grass (Pennisetum purpureum, Schum and mombaça grass pastures (Panicum maximum, Jacq under rotational grazing

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    R.C. Clipes

    2005-02-01

    Full Text Available Avaliaram-se pastagens de capim-elefante e capim-mombaça, por intermédio de amostras de extrusa esofágica e simulação manual de pastejo, estimando-se a composição químico-bromatológica, o fracionamento dos compostos nitrogenados e carboidratos, e a digestibilidade in vitro da matéria seca. Foram utilizados 15 e 13 piquetes de capim-elefante e capim-mombaça, respectivamente, com período de ocupação de três dias. As coletas foram realizadas de forma que se obtivessem amostras relativas ao terceiro, segundo e primeiro dias de ocupação. As metodologias de amostragem foram comparadas dentro de espécie forrageira pelo teste t de Student, com arranjo em pares. Foram observados maiores teores de carboidratos totais, fibra em detergente neutro, fibra em detergente ácido, celulose, lignina e frações de lenta degradação e não degradável dos carboidratos, quando se usou a extrusa esofágica, para ambas as gramíneas. Os teores de carboidratos não-fibrosos foram superiores (PThe methods of esophageal extrusa and hand plucking sample of forage were compared to evaluate elephant grass and mombaça grass pastures, under rotational grazing. The chemical composition, the fractions of nitrogenous and carbohydrates compounds and the in vitro dry matter digestibility were evaluated. For elephant grass and mombaça grass 15 and 13 paddocks were used, respectively, with three days of occupation period and samplings were gotten in the third, second and first days of occupation period. The sampling methodologies were compared within forage species by Student’s t test, in paired arrangement. The contents of total carbohydrates, neutral detergent fiber, acid detergent fiber, cellulose, lignin the slow degradation and undegradable fractions of carbohydrates were higher (P<.05, when esophageal extrusa was used, for both grasses. The non fibrous carbohydrates were higher (P<.05 in hand plucked samples. Higher values (P<.05 were found for

  5. Effect of intercropping Panicum maximum var. Ntchisi and Lablab purpureus on the growth, herbage yield and chemical composition of Panicum maximum var. Ntchisi at different harvesting times.

    Science.gov (United States)

    Ojo, V O A; Dele, P A; Amole, T A; Anele, U Y; Adeoye, S A; Hassan, O A; Olanite, J A; Idowu, O J

    2013-11-15

    The study was conducted to evaluate the effect of intercropping Panicum maximum var. Ntchisi and Lablab purpureus on the growth, herbage yield and chemical composition of P. maximum var. Ntchisi at different harvesting times at the Teaching and Research farm, Federal University of Agriculture, Abeokuta in a randomized complete block design. Samples were collected at different harvesting times (8, 10, 12, 14 weeks after planting). The growth parameters which were plant height, leaf length, leaf number and tiller number measured showed that the intercropping of grass with legume were higher than in the sole plot of P. maximum var. Ntchisi. The plant yield was consistently higher (p < 0.05) in intercropped forages than in sole throughout the harvesting times. The crude protein contents of the forages were also higher for the intercropped across the treatments. The values of the fibre components were significantly different (p < 0.05) at different harvesting times and it was increasing as the harvesting time was increasing. From this study, considering the herbage yield and chemical composition of intecropping Panicum maximum var. Ntchisi and Lablab purpureus, they can be grazed by ruminant animals or harvested at 12 weeks after planting when the quality and quantity will support livestock productivity and can be conserved to be fed to ruminant animals during dry season when feed availability and quality are extremely low.

  6. Estimativas de repetibilidade para caracteres forrageiros em Panicum maximum Repeatability estimates for forage characters in Panicum maximum

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    Francisco José da Silva Lédo

    2008-08-01

    Full Text Available Objetiva-se com este trabalho estimar a repetibilidade para caracteres forrageiros de Panicum, e determinar o número de cortes de avaliação necessários para a seleção de genótipos de Panicum, com confiabilidade. Utilizaram-se os dados de um ensaio conduzido no período de 21/11/2002 a 08/04/2005, no Campo Experimental da Embrapa Gado de Leite, localizado em Valença-RJ, onde foram realizados 15 cortes de avaliação. No ensaio, foram avaliados 23 genótipos de Panicum maximum, em parcelas experimentais, dispostas no delineamento de blocos casualizados, com três repetições. Foram estimados os coeficientes de repetibilidade para as características produção de matéria verde de forragem (PMV; produção de matéria seca de forragem (PMS e de folhas (PMSF; porcentagem de folhas na PMS (%FOL e altura da planta (AP, utilizando os métodos da análise de variância, componentes principais e análise estrutural. Para todas as características avaliadas os efeitos de genótipos, cortes e interação genótipos x cortes foram significativos (PThe objective of this work was to estimate the repeatability for forage characters of Panicum and to determinate the necessary number of evaluation cuts to select Panicum genotypes with confidence. Data of a trial with 15 cuts, carried out between 21/11/2002 and 08/04/2005 in the experimental station of Embrapa Gado de Leite located in Valença, RJ, Brazil, were used. In this study. 23 genotypes of " Panicum maximum" were evaluated, in a complete randomized block, with three replications. The coefficient of repeatability for fresh forage production (PMV, total plant dry matter production (PMS and leaves dry matter production (PMSF were recorded along with leaves percentage in PMS (%FOL and plant hight (AP, using the variance analysis, main components and structural analysis methods. For all evaluated parameters the effects of genotype, cut and genotype x cut interaction were significant (P<0.01. When

  7. Composição química do capim-Mombaça (Panicum maximum Jacq. cv. Mombaça adubado com diferentes fontes de fósforo sob pastejo - DOI: 10.4025/actascianimsci.v29i1.242 Chemical composition of Mombaça grass (Panicum maximum Jacq. cv. Mombaça fertilized with different phosphorus on grazing - DOI: 10.4025/actascianimsci.v29i1.242

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    Ulysses Cecato

    2007-11-01

    Full Text Available O objetivo foi avaliar a composição química do Panicum maximum Jacq. cv. Mombaça, adubado com 140 kg ha-1 de P2O5 com diferentes fontes de fósforo, sob pastejo, no período de dezembro de 2002 a abril de 2003, com intervalo de coleta a cada 28 dias. Tratamentos: 1- termofosfato magnesiano Yoorin®; 2-fosfato natural Gafsa®; 3-superfosfato simples + superfosfato triplo (SS + ST; e 4-testemunha. Os teores de proteína bruta na lâmina foliar (PBf e colmo (PBc, nitrogênio insolúvel em detergente ácido (NIDA, fibra em detergente neutro (FDN, fibra em detergente ácido (FDA, celulose (CEL, hemicelulose (HCEL, lignina (LIG, extrato etéreo (EE, cálcio (Ca, fósforo (P, cinzas e carboidratos não-estruturais (CNE, não foram influenciados pela adubação fosfatada. As variáveis PBc, FDNf, FDNc, LIGf, LIGc, CELf, CELc, NIDAf, EEf, EEc, Caf, Cac, Pf, Pc, CINZAc, CNEc, apresentaram efeito do período de coleta. Não ocorreu diferença na composição química da forragem do capim-Mombaça em função das fontes de fósforo utilizadas na adubação da pastagem. As variações qualitativas foram de baixa magnitude.This study aimed to evaluate the chemical composition of Panicum maximum Jacq. cv. Mombaça. Grassland was fertilized with 140 kg ha-1 of P2O5 from different phosphorus sources on grazing, in December, 2002, until April, 2003, with a collection interval of every 28 days. Treatments: 1-Yoorin® magnesium thermophosphate; 2-Gafsa® natural phosphate; 3-simple superphosphate + triple superphosphate (SS + TS and 4-control. Leaf (lCP and stem (sCP crude protein, acid detergent fiber nitrogen (ADFN, neutral detergent fiber (NDF, acid detergent fiber (ADF, cellulose (CEL, hemicellulose (HEM, lignin (LIG, ether extract (EE, calcium (Ca, phosphorus (P, ash (A and non-structural carbohydrates (NSC were not influenced by phosphated fertilization. The variables sCP, lNDF, sNDF, sLIG, lLIG, sCEL, lCEL, lADFN, sEE, lEE, lCa, sCa, lP, sP, sA and s

  8. Características agronômicas, morfogênicas e estruturais do capim "Panicum maximum" cv. Mombaça sob desfolhação intermitente Characteristics agronomic, morphogenic and structural of the “Panicum maximum” cv. Mombaça grass under intermittent defoliation

    OpenAIRE

    Rafael Henrique Pereira dos Reis; Roberta Gomes Marçal Vieira Vaz; Adriano Jakelaitis; Emerson Alexandrino; Carlos Henrique Oliveira Macedo; Jhony Vendrusculo

    2010-01-01

    Avaliou-se o efeito de dois períodos de descanso sobre as características morfogênicas, estruturais e o acúmulo de forragem do Panicum maximum cv. Mombaça estabelecido na Amazônia Legal. Os tratamentos foram dispostos em delineamento em blocos ao acaso, com quatro repetições. Os períodos avaliados foram de 36 e 48 dias de rebrotação, com 25 cm de altura do corte. Para as características agronômicas avaliadas, apenas a produção de matéria seca de lâmina foliar não foi incrementada com o prolon...

  9. Ensiling characteristics of silages of Stylo legume (Stylosanthes guianensis), Guinea grass (Panicum maximum) and their mixture, treated with fermented juice of lactic bacteria, and feed intake and digestibility in goats of rations based on these silages

    NARCIS (Netherlands)

    Bureenok, S.; Sisaath, K.; Yuangklang, C.; Vasupen, K.; Schonewille, J. Th.

    2016-01-01

    The aim of the current study was to evaluate the ensiling characteristics of silages prepared from Guinea grass, Stylo legume or Stylo legume mixed with Guinea grass (50:50 w/w). Guinea grass and Stylo legume were harvested 45 and 60 days after regrowth, respectively and treated with a fermented

  10. Genetic diversity based on morphological data in Panicum maximum hybrids

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    Janaina Azevedo Martuscello

    2012-09-01

    Full Text Available The objective of this experiment was to evaluate the genetic divergence between hybrids obtained from 10 sexual genitors of the Panicum maximum breeding program at Embrapa Beef Cattle. For this, the following morphological descriptors were used: plant height, growth habit, leaf aspect, leaf waxiness, hair density on the sheath (DePB and blade (DePL, degree of hardiness of the hairs on the leaf sheath (DuPB and blade (DuPL and length of hairs on the sheath and blade. The characteristics growth habit and waxiness were not included in the analysis for being invariant. The phenotypic correlations were low and, therefore, not used to eliminate variables. By the principal component analysis, an 84.3% accumulation of the variation was observed until the fourth component. The last four principal components presented an estimate lower than 0.7 and allowed the identification of the variables DePB, DuPB and DuPL as the least important for diversity studies. The morphological characters used were not efficient to distinguish the progenies, but allowed the formation of morphological groups that converged with the graphic analysis of the principal components. An apparent error rate of 17.04% was observed in the classification of the individuals in the groups and 55.5% in the classification of the individuals in the progenies. The individuals in the P. maximum half-sib progenies are genetically divergent, but may not be grouped with only the descriptors used in this experiment. The pubescence characteristics were the least important in the discrimination of the genotypes.

  11. Acumulación de hojarasca en un pastizal de Panicum maximum y en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala Litter accumulation in a Panicum maximum grassland and in a silvopastoral system of Panicum maximum and Leucaena leucocephala

    Directory of Open Access Journals (Sweden)

    Saray Sánchez

    2007-09-01

    Full Text Available Se realizó un estudio en la Estación Experimental de Pastos y Forrajes "Indio Hatuey", Matanzas, Cuba, con el objetivo de determinar la acumulación de la hojarasca en un pastizal de Panicum maximum Jacq cv. Likoni y en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham. En los pastizales de P. maximum de ambos sistemas se determinó la acumulación de la hojarasca según la técnica propuesta por Bruce y Ebershon (1982, mientras que la hojarasca de L. leucocephala acumulada en el sistema silvopastoril se determinó según Santa Regina et al. (1997. De forma general, los resultados demostraron que en ambos pastizales la guinea acumuló una menor cantidad de hojarasca durante el período junio-diciembre, etapa en la que se produce su mayor desarrollo vegetativo. En la leucaena la mayor producción de hojarasca ocurrió en el período de diciembre a enero, asociada con la caída natural de sus hojas que se produce por efecto de las temperaturas más bajas y la escasa humedad en el suelo. En el sistema silvopastoril la hojarasca de leucaena representó el mayor porcentaje de peso dentro de la producción total, con un contenido más alto de nitrógeno y de calcio que el de la hojarasca del estrato herbáceo. En la guinea la lluvia fue el factor climático que mayor correlación negativa presentó con la producción de hojarasca en ambos sistemas, y en la leucaena la mayor correlación negativa se encontró con la temperatura mínima.A study was carried out at the Experimental Station of Pastures and Forages "Indio Hatuey", Matanzas, Cuba, with the objective of determining the litter accumulation in a pastureland of Panicum maximum Jacq cv. Likoni and in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham. In the P. maximum pasturelands of both systems the litter accumulation was determined by means of the technique proposed by Bruce and Ebershon (1982, while

  12. Leaf Dynamics of Panicum maximum under Future Climatic Changes.

    Science.gov (United States)

    Britto de Assis Prado, Carlos Henrique; Haik Guedes de Camargo-Bortolin, Lívia; Castro, Érique; Martinez, Carlos Alberto

    2016-01-01

    Panicum maximum Jacq. 'Mombaça' (C4) was grown in field conditions with sufficient water and nutrients to examine the effects of warming and elevated CO2 concentrations during the winter. Plants were exposed to either the ambient temperature and regular atmospheric CO2 (Control); elevated CO2 (600 ppm, eC); canopy warming (+2°C above regular canopy temperature, eT); or elevated CO2 and canopy warming (eC+eT). The temperatures and CO2 in the field were controlled by temperature free-air controlled enhancement (T-FACE) and mini free-air CO2 enrichment (miniFACE) facilities. The most green, expanding, and expanded leaves and the highest leaf appearance rate (LAR, leaves day(-1)) and leaf elongation rate (LER, cm day(-1)) were observed under eT. Leaf area and leaf biomass were higher in the eT and eC+eT treatments. The higher LER and LAR without significant differences in the number of senescent leaves could explain why tillers had higher foliage area and leaf biomass in the eT treatment. The eC treatment had the lowest LER and the fewest expanded and green leaves, similar to Control. The inhibitory effect of eC on foliage development in winter was indicated by the fewer green, expanded, and expanding leaves under eC+eT than eT. The stimulatory and inhibitory effects of the eT and eC treatments, respectively, on foliage raised and lowered, respectively, the foliar nitrogen concentration. The inhibition of foliage by eC was confirmed by the eC treatment having the lowest leaf/stem biomass ratio and by the change in leaf biomass-area relationships from linear or exponential growth to rectangular hyperbolic growth under eC. Besides, eC+eT had a synergist effect, speeding up leaf maturation. Therefore, with sufficient water and nutrients in winter, the inhibitory effect of elevated CO2 on foliage could be partially offset by elevated temperatures and relatively high P. maximum foliage production could be achieved under future climatic change.

  13. Análise de crescimento de cultivares de Panicum maximum Jacq. Growth analysis of Panicum maximum Jacq. cultivars

    Directory of Open Access Journals (Sweden)

    Carlos Augusto de Miranda Gomide

    1999-08-01

    Full Text Available O objetivo deste trabalho foi analisar o crescimento de três cultivares de Panicum maximum: Mombaça, Tanzânia e Vencedor cultivados em vasos, sob cobertura de lona plástica transparente. Os vasos foram cheios com 6 dm³ de latossolo vermelho-amarelo, textura argilosa, contendo alto teor de matéria orgânica. O solo, após ser peneirado, recebeu calagem e enriquecimento com N e P, 150 mg/dm³ de cada elemento. As sementes foram plantadas em vasos, num total de 54. Após desbaste, cinco plantas foram deixadas por vaso. Diariamente os vasos foram molhados e quinzenalmente fertilizados, cada um, com 50 mg/dm³ de N e K, em solução aquosa. Cada cultivar foi colhido às idades de 17, 24, 31, 38, 45 e 52 dias após emergência da semente. Houve três repetições para cada cultivar e idade. Em cada colheita, as plantas foram cortadas próximo à superfície do solo e separadas em folhas, colmo, raízes e material morto. A área das lâminas foliares foi medida em integrador de área foliar. Lâminas foliares, colmo e sistema radicular foram pesados após secagem a 60ºC por 72 horas. Valores instantâneos foram estimados para os índices de crescimento: área foliar específica (AFE, razão de peso foliar (RPF, razão de área foliar (RAF, taxa assimilatória líquida (TAL e taxa de crescimento relativo (TCR, de todos três cultivares. Houve diferenças entre os cultivares quanto aos valores instantâneos de RAF e TCR à idade de 17 dias. As variações de AFE foram as principais causas das mudanças em RAF. Nenhuma diferença foi observada entre os cultivares quanto à TAL.The objective of this work was to analyze the growth of three cultivars of Panicum maximum: Mombaça, Tanzânia and Vencedor grown in pots, under a transparent plastic cover. The pots were filled with 6 dm³ of redyellow latossol, clayish texture, with high organic matter content. The soil, after sifted, was limed and enriched with N and P, 150 mg/dm³ of each element. The

  14. Repetibilidade de caracteres agronômicos em Panicum maximum Jacq. Agronomic characters repeatability in Panicum maximum Jacq

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    Janaina Azevedo Martuscello

    2007-12-01

    Full Text Available O experimento foi conduzido para avaliar o coeficiente de repetibilidade de algumas características agronômicas em híbridos de Panicum maximum. Dez parcelas de plantas sexuais da espécie foram aleatoriamente distribuídas entre as 230 parcelas de acessos apomíticos. Após a fecundação natural, sementes de cada planta sexual constituíram-se uma família de meios-irmãos. Trinta plantas de cada progenitora foram avaliadas em delineamento de blocos ao acaso, com cinco plantas por parcela e seis repetições. A partir de cinco cortes, estimou-se o coeficiente de repetibilidade pelos métodos da Análise de Variância, Componentes principais (matriz de correlação e covariância e Análise estrutural. Os coeficientes de repetibilidade (r nos diferentes métodos, para todas as características avaliadas, oscilaram entre 0,51 e 0,86 e podem ser considerados altos, assim como os coeficientes de determinação. As estimativas do coeficiente de repetibilidade obtidas para as quatro características avaliadas pelo método da análise de variância foram quase sempre menores que as obtidas pelos demais métodos. Pelo método dos componentes principais (baseado na matriz de covariância, as estimativas foram sempre maiores em relação aos demais métodos. Considerando satisfatórios níveis de 80 ou 90% de confiabilidade para avaliação da superioridade relativa dos híbridos para todas as características avaliadas, as cinco medições realizadas são suficientes para escolha da melhor planta. A exclusão dos cortes 1 e 2 promove aumento nos coeficientes de repetibilidade e determinação.The experiment was carried out to evaluate the coefficient of repeatability of some agronomic characteristics in Panicum maximum hybrids. Ten plots of sexual plants of this species were randomly distributed among 230 plots of apomitic accessions. After natural hybridization, seeds of each sexual plant constituted a half-sib family. Thirty plants of each female

  15. EFEITO DO TIPO DE EMBALAGEM SOBRE A QUALIDADE DAS SEMENTES DE CAPIM COLONIÃO (Panicum maximum Jacq ARMAZENADAS SOB DIFERENTES CONDIÇÕES DE AMBIENTE COLONIÃO GRASS (Panicum maximum JACQ SEED PRESERVATION IN MOISTURE AND PACKAGE EFFECT

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    Sílvio Moure Cícero

    2007-09-01

    ="font-style: normal;">This research was conducted at Laboratório de Análise de Sementes of Escola Superior de Agricultura Luiz de Queiroz, University of São Paulo, for the purpose of determining which of the several materials used to seed packaging contributed most efficiently to the preservation of colonião pasture grass seed. Seeds of two lots, with 9.7% e 12% of moisture, were stored in packages made of the following materials: cotton sacks, layered kraft paper (four layers, and polyethylene (bags 0.35 mm thick. The plastic bags were hot sealed. These packages, each with 1.5 kg of seeds, were stored for one year under three conditions: warehouse (without temperature and moisture control; city chamber (temperature of 25°C and moisture of 45% and cold chamber (temperature of 10°C and moisture of 90%. Seed characteristics were tested: moisture level, seed germination, first counting, emergence, accelerated aging and electric conductivity, in a randomized experimental design with four replications. From the statistical analysis of data, the conclusions were the following: a seeds stored in warehouse were better preserved when packed in layered kraft paper; b seeds stored in a dry chamber were better preserved when packed in layered kraft paper and cotton bags; c seeds stored in a cold chamber were better preserved when packed in polyethylene sacks.

    KEY-WORDS: Storage; colonião grass; seed.

  16. The distribution of 137Cs in maize (Zea mays L.) and two millet species (Panicum miliaceum L. and Panicum maximum Jacq.) cultivated on the cesium-contaminated soil

    International Nuclear Information System (INIS)

    Bystrzejewska-Nowacka, G.; Nowacka, R.

    2004-01-01

    The plant of three species (Zea mays L., Panicum miliaceum L. and Panicum maximum Jacq.) were grown on the soil contaminated with 0.3 mM CsCl solution traced with 137 Cs, in greenhouse. For all the species, the fresh-to-dry weight ratio was equal in the cesium-treated plants and in the central group after 3 weeks of culture. The shoot-to root fresh weight and dry weight ratios were decreased in maize, unchanged in Panicum miliaceum and increased in Panicum maximum, comparing to the control without cesium treatment. The shoot/soil and also root/soil transfer (TF) for 137 Cs (measured by means of Na I gamma spectrometer) were always the highest in maize, then lower in Panicum miliaceum and the lowest in Panicum maximum. All the plants seem to be hyperaccumulators of cesium. The root/soil Tf was especially high in maize, i.e. 55 (kBq kg -1 biomass)/kBq Kg -1 soil). The shoot/root concentration factor (CF) for 137 Cs was the lowest in maize, higher in Panicum miliaceum and highest in Panicum maximum. The proved ability of the investigated plants for phytoextraction of the soil cesium points to the (author). The detectability and reliin soil bioremediation. From this point of view, Panicum maximum seems to be the most useful plant because it accumulates cesium mainly in the shoot, and maize would be the least useful spices since it has the highest accumulation in root. (author)

  17. Queilite angular traumática em eqüinos associada à ingestão de Panicum maximum Angular cheilitis in horses associated with ingestion of Panicum maximum

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    José Diomedes Barbosa

    2009-05-01

    Full Text Available Uma condição com aumento da fenda bucal de eqüinos por lesão na comissura labial foi estudada. Este aumento tinha extensão variável e era uni ou bilateral. Na mucosa da bochecha da comissura labial exposta havia pequenas erosões. Durante a mastigação havia perda de pequena quantidade de capim e saliva pela fenda bucal aumentada. Os animais apresentavam bom estado nutricional. O exame histopatológico de tecido retirado da comissura labial revelou epidermite superficial. Nas quatro propriedades onde se verificou o problema, constatou-se que os eqüinos eram mantidos em sistema extensivo de criação em pastagem de Panicum maximum (variedades Tanzânia, Mombaça, Tobiatã e Colonião, com folhas maduras, altas, lignificadas e de bordos cortantes. De acordo com os dados epidemiológicos, com os achados clínicos e histopatológicos, concluí-se que essas lesões foram causadas pela ação cortante das folhas de Panicum maximum, associada à forma de apreensão da pastagem alta e mastigação pelos eqüinos.A condition with enlargement of the oral cleft in horses was studied. The enlargement of varied extension was uni or bilateral. The cheek mucosa of the labial commissure showed slight erosions. During chewing there was loss of small amounts of grass and saliva through the oral cleft. The affected horses were in good nutritional condition. Histopathological studies of tissues obtained by biopsia, revealed a superficial epidermitis. The pastures consisted of Panicum maximum grass (varieties Tanzânia, Mombaça, Tobiatã and Colonião which was mature, tall, lignified, with leaves of cutting edges. Based on epidemiological, clinical and histopathological data, it was concluded that the lesions were caused by the hard grass, favored by the way horses pull the tall grass and chew it.

  18. Composição químico-bromatológica da forragem durante o período de ocupação em pastagens de capim-elefante (Pennisetum purpureum, Schum e capim-mombaça (Panicum maximum, Jacq sob manejo rotacionado Forage composition during the occupation period in elephant grass (Pennisetum purpureum, Schum and mombaça grass (Panicum maximum, Jacq pastures under rotational system

    Directory of Open Access Journals (Sweden)

    R.C. Clipes

    2006-10-01

    Full Text Available Os valores nutritivos do capim-elefante e do mombaça foram avaliados por intermédio de amostras de extrusa esofágica, determinando-se a composição químico-bromatológica, o fracionamento dos compostos nitrogenados e carboidratos, e a digestibilidade in vitro da matéria seca. Foram utilizados 15 e 13 piquetes de capim-elefante e capim-mombaça, períodos de descanso de 42 e 36 dias, respectivamente, e período de ocupação de três dias. Em cada pastagem, eram mantidas quatro novilhas mestiças. As coletas de extrusa foram realizadas, seqüencialmente em cada piquete ocupado, de forma que se obtivessem amostras do terceiro, segundo e primeiro dias de ocupação. A comparação entre as médias das amostras de extrusa dos primeiros, segundos e terceiros dias de ocupação foi realizada por contrastes ortogonais e equações de regressão. No capim-mombaça foi observado comportamento quadrático (P0,05.The chemical composition, the fractions of nitrogenous and carbohydrates compounds and the in vitro dry matter digestibility, were evaluated in elephant and mombaça grasses pastures under rotational system. Fifteen paddocks of elephant grass and thirteen of mombaça grass were used with three days of occupation period and 42 and 36 days of resting periods, respectively. Extrusa samplings were done in order to get samples relating to third, second and first days of the occupation period. In each pasture were kept four crossbreds heifers. The comparison between the average composition of esophageal extrusa samples of to the first, second and third days of the occupation periods was done by the orthogonal contrast, with further adjustment by regression equations. For mombaça grass it was observed quadratic behavior (P0.05.

  19. Effect of sources of phosphorus on “in vitro” digestibility of dry matter, organic matter and total digestible nutrients of Mombaça grass (Panicum maximum Jacq. Cv. Mombaça/ Efeito de fontes de fósforo sobre a digestibilidade “in vitro” da matéria seca, da matéria orgânica e nutrientes digestíveis totais do capim- Mombaça (Panicum maximum Jacq. Cv. Mombaça

    Directory of Open Access Journals (Sweden)

    Carlos Antonio Lopes de Oliveira

    2008-08-01

    Full Text Available The trial was performed to evaluate the effect of phosphorus sources on forage mass quality of Mombaça grass (Panicum maximum Jacq. cv. Mombaça, according to in vitro dry matter and organic matter digestibility and TDN concentration. Every month, samples of available forage mass were taken, from December, 2002 until April, 2003. The treatments were three phosphate sources (1-YoorinÆÊ magnesium thermophosphate; 2-GafsaÆÊ natural phosphate; 3-simple superphosphate + triple superphosphate and the control (no fertilizer. They were arranged in a randomised block design with three replications. It was used 12 plots sized from 0,7 to 1,0 hectare, which were delimited by two-line eletric fence. The grazing method was continuous stocking and variable stocking rate (“put-and-take”. The IVDMD, IVOMD and TDN coefficients decreased along sampling period. IVDMD, IVOMD and TDN concentration didn’t show significantly differences among treatments (P>0.05.O trabalho foi realizado com o objetivo de avaliar o efeito de fontes de fósforo sobre a qualidade de massa de forragem do capim-Mombaça (Panicum maximum Jacq. cv. Mombaça, no que se refere à digestibilidade “in vitro” da matéria seca e da matéria orgânica e concentração de NDT. Foram feitas amostragens mensais da massa de forragem disponível, no período de dezembro de 2002 a abril de 2003. Os tratamentos avaliados foram três fontes de fósforo (1-termofosfato magnesiano YoorinÆÊ; 2-fosfato natural GafsaÆÊ; 3-superfosfato simples + superfosfato triplo e tratamento testemunha, distribuídos em delineamento de blocos casualisados com três repetições. Foram utilizados 12 piquetes com tamanho de 0,7 a 1,0 hectare, separados por cerca com dois fios eletrificados. O método de pastejo utilizado foi o da lotação contínua com carga variável (“put-and-take”. Os coeficientes de DIVMS, DIVMO e NDT reduziram ao longo do período de coleta. Entre os tratamentos, a DIVMS, DIVMO e

  20. Total number of tillers of different accessions of Panicum maximum Jacq.

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    Thiago Perez Granato

    2012-12-01

    Full Text Available The productivity of forage grasses is due to continuous emission of leaves and tillers, ensuring the restoration of leaf área after cutting or grazing, thus ensuring the sustainability of forage. This study aimed to asses the total number tillers in different acessions of Panicum maximum Jacq. The experiment was carried in field belonging to the Instituto de Zootecnia located in Nova Odessa / SP. Evaluated two new accesses Panicum maximum, and two commercial cultivars. The cultivars tested were Aruana, Milenio, NO 2487, NO 78, and the two latter belonging to the Germoplasm Collection of the IZ. The experimental desing was in randomized complete block with four replications. The experimental area consisted of 16 plots of 10 m2 (5 x 2 m each. The experimental area was analyzed and according to the results, received dolomitic limestone corresponding 2t /ha, two months before the implementation of the experiment. Sowing was made by broad costing together with 80 kg/ha of P2O5 in the form of single superphosfate. After 60 days of implantation of the experiment it was a made a leveling of the plots to a height of about 15 cm. After this it was applied 250g of the 20-00-20 fertilizer/plot. Thirty days after the standardization it was evaluated the total number of tillers of the cultivars, using a metal frame of 0.5 x 0.5m which was thrown at random on each of the 16 plots, leaving one meter of each extremitly, and all tillers which were within the frame counted. After finished the counting of all tillers, the plots cut again at a height of approximately 15 cm. The second evaluation took place after thirty days, and it was again counted the total number of tillers following the same procedure. The results were analyzed by Tukey test at 5% after transforming the data to log(x. For the first evaluation there was no statistical difference in the total number of tillers between cultivars. But, in the second evaluation, the total number of tillers of NO 78

  1. An evaluation of Panicum maximum cv. Gatton: 1. The effect of ...

    African Journals Online (AJOL)

    Unknown

    The aim of this study was to evaluate the livestock production potential of Panicum maximum cv. Gatton ... consumed which varies according to the quantity and quality of forage on offer (Heitschmidt et al., 1990). The .... Dry matter availability differed between treatments both at the beginning and end of each grazing period.

  2. Selection of full-sib families of Panicum maximum Jacq under low light conditions

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    Douglas Mochi Victor

    2015-04-01

    Full Text Available The silvopastoral system is a viable technological alternative to extensive cattle grazing, however, for it to be successful, forage grass genotypes adapted to reduced light need to be identified. The objective of this study was to select progenies of Panicum maximum tolerant to low light conditions for use in breeding programs and to study the genetic control and performance of some traits associated with shade tolerance. Six full-sib progenies were evaluated in full sun, 50% and 70% of light reduction in pots and subjected to cuttings. Progeny genotypic values ​​(GV increased with light reduction in relation to plant height (H and specific leaf area (SLA. The traits total dry mass accumulation (DM and leaf dry mass accumulation (LDM had GV higher in 50% shade and intermediate in 70% shade. The GV of tiller number (TIL and root dry mass accumulation (RDM decreased with light reduction. The highest positive correlations were obtained for the traits H and RDM with SLA and DM; the highest negative correlations were between TIL and SLA and RDM, and H and LDM. The progenies showed higher tolerance to 50% light reduction and, among them, two stood out and will be used in breeding programs. It was also found that it is not necessary to evaluate some traits under all light conditions. All traits had high broad sense heritability and high genotypic correlation between progenies in all light intensities. There is genetic difference among the progenies regarding the response to different light intensities, which will allow selection for shade tolerance

  3. An evaluation of Panicum maximum cv. Gatton: 3. The partial ...

    African Journals Online (AJOL)

    NDF disappearance from the total tract decreased with increasing pasture maturity during all seasons. It was concluded that P. maximum cv. Gatton pasture would best be utilized at the younger stages of development and that nutritional value would be higher in summer followed by younger autumn and winter pastures.

  4. Assessment of the phytoremediation potential of Panicum maximum ...

    African Journals Online (AJOL)

    Obvious signs of phyto-toxicity however appeared in plants exposed to 120 ppm Pb2+ and Cd2+ at day twenty-three, suggesting that P. maximum may be a moderate metal accumulator. Keywords: phytoremediation, heavy metals, uptake, tissues, accumulator. African Journal of Biotechnology, Vol 13(19), 1979-1984 ...

  5. Morphological characters of Panicum maximum cv Gatton planted from different source of sapling

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    Fanindi A

    2014-03-01

    Full Text Available Morphological characters and agronomic information of Panicum maximum cv Gatton is required in forage crop breeding activities. Therefore a research was conducted to determine the morphology and characteristic of generative phase of Panicum maximum cv Gatton. The study was conducted in greenhouses, using a 40 cm diameter pot. The planting medium was soil from Ciawi (Latosol. Research design was Completely Randomized Design, with 10 replications. Treatments used were 2 types of planting material, 1 derived from the pols (vegetative and 2 seeds. Plants used were Panicum maximum cv Gatton that have been collected and evaluated at the IRIAP, Ciawi. Variables measured were plant morphology, reproductive traits, seed production per panicle and seed quality. Results showes that morphological characters of cv Gatton derived from seed and pols was not significantly different (p > 0.05, whereas the flowering time and the time of seeds mature after cutting derived from the seeds was faster (p < 0.05 than cultivars derived from pols. While the production of seed derived from the seeds was higher (p < 0.05 when compared to that derived from the pols.

  6. Fungic microflora of Panicum maximum and Styosanthes spp. commercial seed / Microflora fúngica de sementes comerciais de Panicum maximum e Stylosanthes spp.

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    Larissa Rodrigues Fabris

    2010-09-01

    Full Text Available The sanitary quality of 26 lots commercial seeds of tropical forages, produced in different regions (2004-05 and 2005-06 was analyzed. The lots were composed of seeds of Panicum maximum ('Massai', 'Mombaça' e 'Tanzânia' and stylo ('Estilosantes Campo Grande' - ECG. Additionally, seeds of two lots of P. maximum for exportation were analyzed. The blotter test was used, at 20ºC under alternating light and darkness in a 12 h photoperiod, for seven days. The Aspergillus, Cladosporium and Rhizopus genus consisted the secondary or saprophytes fungi (FSS with greatest frequency in P. maximum lots. In general, there was low incidence of these fungus in the seeds. In relation to pathogenic fungi (FP, it was detected high frequency of contaminated lots by Bipolaris, Curvularia, Fusarium and Phoma genus. Generally, there was high incidence of FP in P. maximum seeds. The occurrence of Phoma sp. was hight, because in 81% of the lots showed incidence superior to 50%. In 'ECG' seeds it was detected FSS (Aspergillus, Cladosporium, and Penicillium genus and FP (Bipolaris, Curvularia, Fusarium and Phoma genus, usually, in low incidence. FSS and FP were associated to P. maximum seeds for exportation, with significant incidence in some cases. The results indicated that there was a limiting factor in all producer regions regarding sanitary quality of the seeds.Sementes comerciais de forrageiras tropicais, pertencente a 26 lotes produzidos em diferentes regiões (safras 2004-05 e 2005-06, foram avaliadas quanto à sanidade. Foram analisadas sementes de cultivares de Panicum maximum (Massai, Mombaça e Tanzânia e de estilosantes (Estilosantes Campo Grande – ECG. Adicionalmente, avaliou-se a qualidade sanitária de dois lotes de sementes de P. maximum destinados à exportação. Para isso, as sementes foram submetidas ao teste de papel de filtro em gerbox, os quais foram incubados a 20ºC, com fotoperíodo de 12 h, durante sete dias. Os fungos saprófitos ou

  7. Effet de Panicum maximum sur la productivité des femelles primipares durant le cycle de reproduction chez le cobaye (Cavia porcellus L.)

    OpenAIRE

    Danho, M.; Thys, E.; N'Goran D.V. Kouakou; Nogbou Assidjo, E.; Grongnet, JF.

    2012-01-01

    Effect of Panicum maximum on Productivity of Primiparous Females during Reproduction Cycle in Guinea Pigs (Cavia porcellus L.). In Ivory Coast, Guinea pigs reared for meat (Cavia porcellus L.) are mainly fed with Panicum maximum. To assess the effect of the latter during pregnancy and lactation (RC) of these animals, primiparous dams were fed ad libitum, Panicum maximum alone during the RC (MOD1) or associated with pellets for rabbits during lactation (MOD2), or associated with pellets for ra...

  8. PRODUTIVIDADE E DEGRADABILIDADE RUMINAL DA FORRAGEM DE CAPINS da espécie Panicum maximum

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    Carlos Guilherme Silveira Pedreira

    2014-09-01

    Full Text Available O objetivo do presente estudo foi avaliar o acúmulo de forragem durante o verão agrostológico e a degradabilidade ruminal da matéria seca, fibra em detergente neutro e fibra em detergente ácido da forragem de cinco capins do gênero Panicum (Mombaça, Tanzânia, Massai, Tobiatã e Atlas em Piracicaba, SP. O período experimental foi de setembro de 2003 a março de 2004. Os intervalos de colheita foram fixados em períodos de 28 dias para Atlas, Massai e Mombaça e em períodos de 35 dias para Tanzânia e Tobiatã, em função de suas características morfológicas e estruturais. Amostras de forragem foram incubadas, adotando-se seis tempos de incubação: 96; 48; 24; 12; 6; 3 e 0 horas. Os cultivares Mombaça (15.500 kg MS ha-1 e Massai (20.400 kg MS ha-1 destacaram-se com as maiores produções de forragem. O estudo da degradabilidade in situ mostrou que, embora sua composição química seja bastante semelhante, alguns fatores importantes como a degradabilidade potencial, tempo de colonização e degradabilidade efetiva diferem entre genótipos, o que sugere diferentes potenciais de produção animal. Palavra-chave: gramínea, in situ, incubação, tempo de colonização.   FORAGE YIELD AND RUMINAL DEGRADABILITY OF FIVE Panicum spp GRASSES ABSTRACT The aim of this study was to evaluate the forage yield during the growing season of 2003/2004 as well as the ruminal dry matter degradability, neutral detergent fiber and acid detergent fiber concentration in the forage of five Panicum grasses (Mombaça, Tanzânia, Massai, Tobiatã and Atlas in Piracicaba, SP. Rest period was fixed on 28 days for Atlas, Massai and Mombaça and 35 days for Tanzânia and Tobiatã, according to their morphologic and structural characteristics. The samples were incubated for 96; 48; 24; 12; 6; 3 and 0 hours. Mombaça (15500 kg DM ha-1 and Massai (20400 kg DM ha-1 were the highest yielding genotypes. Ruminal degradability showed that, although chemical composition

  9. Efecto de la altura de poda en Leucaena leucocephala y su influencia en el rebrote y rendimiento de Panicum maximum

    OpenAIRE

    H. M. Bacab; F. J. Solorio; S. B. Solorio

    2012-01-01

    Una de las prácticas importantes de manejo en los sistemas de Leucaena leucocephala asociada con pastos tropicales, como Panicum maximum, es la poda; en la actualidad se continúan los estudios para determinar los efectos de esta práctica en el componente arbóreo y herbáceo. Por todo ello, en el presente trabajo se evaluó el efecto de tres alturas de poda en Leucaena leucocephala cv. Cunningham y su influencia en la pastura asociada (Panicum maximum cv. Tanzania). El estudio se realizó en la é...

  10. Consumo voluntário de forragem de três cultivares de Panicum maximum sob pastejo Voluntary intake of three cultivars of Panicum maximum under grazing

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    Valéria Pacheco Batista Euclides

    1999-01-01

    Full Text Available Os objetivos deste trabalho foram estimar o consumo de matéria seca de animais pastejando três cultivares de Panicum maximum e relacioná-lo com ganho de peso, tempo de pastejo (TP e algumas características químicas e estruturais do pasto. O delineamento experimental foi o de blocos casualizados com três tratamentos e três repetições. O consumo voluntário de matéria seca (CVMS foi estimado em quatro ocasiões (maio, setembro, novembro e fevereiro. Para calcular a produção de fezes, foi usado o óxido crômico como marcador externo. Foram estimados a digestibilidade in situ da matéria seca e o tempo de pastejo, respectivamente, por intermédio de extrusas e tacógrafos. Foram estimadas as disponibilidades da forragem e dos componentes da planta. Apesar de os CVMS pelos animais terem sido semelhantes entre as cultivares, foram observadas maiores diferenças nos ganhos de peso, para os animais pastejando o capim Tanzânia, seguidos daqueles pastejando os capins Colonião e Tobiatã. Diferenças também foram observadas entre as cultivares para TP, que foi menor para os animais em pasto de Tobiatã, quando comparados aos que pastejaram as outras duas cultivares. O aumento no TP observado durante o período da seca não foi suficiente para impedir queda no consumo de forragem neste período. O CVMS foi correlacionado (r² = 0,77 com ganho diário de peso. As características estruturais das pastagens, disponibilidade de folhas e relação material verde:material morto, influenciaram mais o CVMS, ganho de peso diário e TP que os valores nutritivos das mesmas.The objectives of this work were to estimate the dry matter intake by animals grazing three cultivars of Panicum maximum, and to relate it to live weight gain, grazing time (GT and some structural and chemical characteristics of the pastures. The experimental design was the randomized block with three treatments and three replicates. The dry matter voluntary intake (DMVI was

  11. Effet de l'herbe de Guinée ( Panicum maximum Jacq.) associée à l ...

    African Journals Online (AJOL)

    Effet de l'herbe de Guinée ( Panicum maximum Jacq.) associée à l'herbe de lait ( Euphorbia heterophylla L.) ou aux feuilles de patate douce ( Ipomoea batatas (L.) Lam) sur la croissance des lapins ( Oryctolagus cuniculus L.)

  12. Modelling of excess noise attnuation by grass and forest | Onuu ...

    African Journals Online (AJOL)

    , guinea grass (panicum maximum) and forest which comprises iroko (milicia ezcelea) and white afara (terminalia superba) trees in the ratio of 2:1 approximately. Excess noise attenuation spectra have been plotted for the grass and forest for ...

  13. Produção de forragem do capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 pastejado em diferentes alturas Forage production of Tanzaniagrass (Panicum maximum Jacq. cv. Tanzania-1 grazed at different heights

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    Clovenilson Cláudio Perissato Cano

    2004-12-01

    Full Text Available Objetivou-se, com este experimento, avaliar a massa de forragem (MF, massa de lâmina verde (MLV, massa de colmo + bainha verde (MCV, massa de material morto (MMM, massa de forragem verde (MFV, relação folha/colmo (F/C, taxa de acúmulo de massa seca (TAMS, acúmulo de massa de forragem (AMF, índice de área foliar (IAF, porcentagem de solo descoberto (SD e porcentagem de solo coberto com liteira (SCL em pastagem de capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 manejada em quatro alturas do dossel forrageiro (20, 40, 60 e 80 cm. O método de pastejo utilizado foi o de lotação contínua e taxa de lotação variável, com novilhos da raça Nelore com peso médio de 340 kg. Utilizou-se o delineamento experimental inteiramente casualizado com duas repetições e realizaram-se cinco avaliações. MLV, MCV, MMM, MFV, MF, IAF, TAMS e AMF aumentaram com o avanço da altura do dossel, sendo que a porcentagem de SD, SCL e material morto diminui em pastos mais altos. O manejo do capim-Tanzânia nas alturas de 40 e 60 cm, apresentou as melhores respostas de composição morfológica, garantindo boa oferta de folhas, de cobertura do solo e taxa de acúmulo de massa seca. As alturas de 20 e 80 cm não devem ser recomendadas para o manejo do capim-Tanzânia quando o objetivo for produção com qualidade e quantidade.This experiment was conducted out to evaluate the forage mass (FM, green leaf lamina mass (GLLM, green stem + leaf sheath mass (GSSM, mass of dead material (MDM, green forage mass (GMF, total forage mass (TFM, leaf/stem ratio (L/S, dry matter accumulation rate (DMAR, leaf area index (LAI, % of bare soil (BS and litter cover percentage (LCP in Tanzaniagrass pasture (Panicum maximum Jacq. cv. Tanzania-1 managed at four different sward heights (20, 40, 60 and 80 cm. The grazing method was the continuous stocking with variable stocking rate, and the grazing animals were Nellore steers with average weight of 340 kg. The completely

  14. Produtividade do Panicum maximum cv. Mombaça irrigado, sob pastejo rotacionado

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    Müller Marcela dos Santos

    2002-01-01

    Full Text Available O uso da irrigação em pastagens é uma realidade fundamentada na experiência empírica de produtores, devido à falta de bases científicas definidas sobre o assunto. O trabalho visou avaliar a produtividade do capim Mombaça (Panicum maximum Jacq. cv. Mombaça manejado em pastejo rotacionado, sob sistema de irrigação e as principais variáveis climáticas responsáveis pelo acúmulo de massa de forragem. O experimento foi conduzido sob irrigação por aspersão tipo pivô central, de julho a dezembro de 1998, em região de cerrado (Latossolo Vermelho-Amarelo em São Desidério, BA. Foi quantificada a massa de forragem da pastagem aos 30 dias de crescimento e antes do pastejo e desenvolvidos modelos matemáticos que relacionam a produção de forragem a variáveis climáticas. A produção e a taxa de acúmulo de matéria seca da pastagem, ao longo do período de inverno não apresentaram diferenças significativas. Na primavera, houve tendência de aumento em ambas, com maiores produções obtidas no período final de avaliação. As menores taxas de acúmulo durante a primavera foram observadas nos primeiros piquetes, coincidindo com a ocorrência de baixas temperaturas durante o período de descanso. Com a elevação da temperatura mínima, a produção forrageira entrou em fase de acúmulo crescente. A produção de forragem, durante a primavera, foi superior à do inverno, apresentando incrementos em função da maior temperatura mínima do ar, do período de descanso e da área foliar inicial. As principais variáveis climáticas responsáveis pela produção da forragem foram temperatura mínima do ar e disponibilidade de água no solo.

  15. Efecto de la altura de poda en Leucaena leucocephala y su influencia en el rebrote y rendimiento de Panicum maximum

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    H. M. Bacab

    2012-01-01

    Full Text Available Una de las prácticas importantes de manejo en los sistemas de Leucaena leucocephala asociada con pastos tropicales, como Panicum maximum, es la poda; en la actualidad se continúan los estudios para determinar los efectos de esta práctica en el componente arbóreo y herbáceo. Por todo ello, en el presente trabajo se evaluó el efecto de tres alturas de poda en Leucaena leucocephala cv. Cunningham y su influencia en la pastura asociada (Panicum maximum cv. Tanzania. El estudio se realizó en la época poco lluviosa del año (marzo a mayo de 2010, se utilizó un diseño de bloques completos al azar con cuatro repeticiones. Al inicio del experimento se asignaron los tratamientos (alturas de poda de 20, 40 y 60 cm sobre el nivel del suelo para Leucaena leucocephala. En el caso de Panicum maximum, se realizó una poda a 5 cm sobre el nivel del suelo en todas las parcelas experimentales. Los resultados obtenidos indicaron que la poda de la leguminosa a 40 y 60 cm permitió obtener brotes de mayor talla, sin afectar a la gramínea asociada. De igual manera, al incrementar la altura de poda, la leguminosa presentó mayor rendimiento y proporción de forraje comestible; sin embargo, se afectó negativamente a la pastura asociada. Ante ello, considerándose el aspecto animal, se recomienda no reducir la altura de poda de Leucaena leucocephala a menos de 40 cm, ya que se reduce significativamente el rendimiento y la proporción de forraje comestible de esta leguminosa, el cual es de mayor calidad para la alimentación animal.

  16. CINÉTICA DE DEGRADABILIDAD in vitro DE CUATRO VARIEDADES DE Panicum maximum COSECHADAS A CUATRO EDADES

    OpenAIRE

    Juan Humberto Avellaneda Cevallos; Carlos Alberto Molina Hidrovo; Wilson Roberto Briones Caicedo; Máximo Fernando Tubay Moreira; Santiago Coello Díaz

    2015-01-01

    Se evaluó la degradabilidad in vitro de la materia seca (MS) de las hojas, tallos y planta completa de cuatro variedades de pasto Guinea (Panicum maximum: Común, Tanzania, Enano y Tobiata) en cuatro edades de cosecha (21, 42, 63 y 84 d). Se evaluó la composición química de las variedades. Para la digestibilidad in vitro, se empleó la primera fase de la técnica de Tilley y Terry, para lo cual se extrajo líquido ruminal de dos bovinos Brown Swiss canulados a rumen. Se evaluaron seis periodos de...

  17. CINÉTICA DE DEGRADABILIDAD in vitro DE CUATRO VARIEDADES DE Panicum maximum COSECHADAS A CUATRO EDADES

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    Juan Humberto Avellaneda Cevallos

    2015-12-01

    Full Text Available Se evaluó la degradabilidad in vitro de la materia seca (MS de las hojas, tallos y planta completa de cuatro variedades de pasto Guinea (Panicum maximum: Común, Tanzania, Enano y Tobiata en cuatro edades de cosecha (21, 42, 63 y 84 d. Se evaluó la composición química de las variedades. Para la digestibilidad in vitro, se empleó la primera fase de la técnica de Tilley y Terry, para lo cual se extrajo líquido ruminal de dos bovinos Brown Swiss canulados a rumen. Se evaluaron seis periodos de incubación (3, 6, 12, 24, 48 y 72 h. Para la cinética de degradación in vitro, se aplicó un diseño de bloques completos al azar (DBCA, utilizando a la corrida (2 como criterio de bloqueo y repetición; se usó una incubadora DaisyII 200 y una bolsita de degradabilidad por corrida. Se observó que la mejor degradabilidad in vitro se presenta en los primeros estadios fenológicos, y que las hojas demuestran mayores características nutricionales, seguida de la planta completa y tallos. Se demostró que las diferencias en degradabilidad no están fuertemente asociadas con la variedad de Panicum maximum, sino más bien con la edad de cosecha. Por lo que se concluye, que la degradabilidad in vitro de las variedades de pasto Guinea, difieren en función del estado de madurez de la planta.

  18. Mapeamento da distribuição espacial da infestação de Panicum maximum durante a colheita da cultura de milho Mapping of the spatial distribution of Panicum maximum during corn harvesting

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    L.S. Shiratsuchi

    2004-06-01

    Full Text Available Metodologias de mapeamento de plantas daninhas em áreas agrícolas estão sendo utilizados a fim de gerar mapas de aplicação localizada de herbicidas, sendo que, este mapeamento vem sendo feito através de ferramentas da agricultura de precisão. O mapeamento das plantas daninhas gera então mapas de tratamentos de herbicidas que comandam pulverizadores capazes de realizar a aplicação localizada de herbicidas, aproveitando o comportamento contagioso inerente da comunidade das plantas daninhas, porém poucos experimentos relatam a eficiência desses métodos. Este experimento teve como objetivo comparar metodologias de mapeamento do capim-colonião (Panicum maximum, com base na avaliação visual durante e após a colheita da cultura de milho. Durante a colheita foi conduzido o monitoramento com avaliação visual, feito por uma pessoa devidamente treinada e pelo operador antecipadamente orientado. Após a colheita, a avaliação visual foi feita por amostragens, numa grade regular de 20 x 20 m. Foi observada uma subestimação de 6% da área infestada, com uma infestação de mais de 80% de cobertura pelo método de mapeamento durante a colheita, quando comparado com o caminhamento na grade regular após a colheita. Os dois métodos foram coincidentes em 45% da área marcada.Weed mapping methodologies are being tested in agricultural fields to generate maps of spotted application of herbicides by using precision farming tools. Weed mapping may generate herbicide treatment maps, allowing herbicide spray only where needed. However, few experiments have reported the efficiency of these methods. This research aimed to compare Panicum maximum mapping methodologies based on visual assessment during and after corn harvesting. Monitoring combined with visual assessment was performed during harvesting by a duly trained worker and a previously oriented operator. Visual assessment was done by samplings after harvesting in a regular 20 x 20 m grid. An

  19. Efeito do hexazinone isolado e em mistura na eficiência fotossintética de Panicum maximum Effect of hexazinone applied alone and in combination on the photosynthetic efficiency of Panicum maximum

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    M. Girotto

    2012-06-01

    Full Text Available Esta pesquisa teve como objetivo avaliar a velocidade e intensidade de ação do hexazinone isolado e em mistura com outros inibidores do fotossistema II, através da eficiência fotossintética de Panicum maximum em pós-emergência. O ensaio foi constituído de seis tratamentos: hexazinone (250 g ha-1, tebuthiuron (1,0 kg ha-1, hexazinone + tebuthiuron (125 g ha-1 + 0,5 kg ha-1, diuron (2.400 g ha-1, hexazinone + diuron (125 + 1.200 g ha-1, metribuzin (1.440 g ha-1, hexazinone + metribuzin (125 + 720 g ha-1 e uma testemunha. O experimento foi instalado em delineamento inteiramente casualizado, com quatro repetições. Após a aplicação dos tratamentos, as plantas foram transportadas para casa de vegetação sob condições controladas de temperatura e umidade, onde ficaram durante o período experimental, sendo realizadas as seguintes avaliações: taxa de transporte de elétrons e análise visual de intoxicação. A avaliação com o fluorômetro foi realizada nos intervalos de 1, 2, 6, 24, 48, 72, 120 e 168 horas após a aplicação, e as avaliações visuais, aos três e sete dias após a aplicação. Os resultados demonstraram diferença nos tratamentos, enfatizando a aplicação do diuron, que reduziu lentamente o transporte de elétrons comparado com os outros herbicidas e, em mistura com hexazinone, apresentou efeito sinérgico. Verificou-se com o uso do fluorômetro a intoxicação antecipada em plantas de P. maximum após a aplicação de herbicidas inibidores do fotossistema II de forma isolada e em mistura.This work aimed to evaluate the speed and intensity of action of hexazinone applied alone and in combination with other photo-system II inhibitors on the photosynthetic efficiency of Panicum maximum in post-emergence. The assay consisted of six treatments: hexazinone (250 g ha-1, tebuthiuron (1.0 kg ha-1, hexazinone + tebuthiuron (125 g ha-1+ 0.5 kg ha-1, diuron (2,400 g ha-1, hexazinone + diuron (125 + 1,200 g ha-1, metribuzin

  20. TERMINAÇÃO DE BOVINOS BRANGUS INTEIROS E CASTRADOS COM CANA-DEAÇÚCAR (SACCHARUM OFFICINARUM OU SILAGEM DE CAPIM MOMBAÇA (PANICUM MAXIMUM CV MOMBAÇA

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    Marcelo Diniz dos Santos

    2014-06-01

    Full Text Available The aim of this study was to evaluate the intake, weight gain, feed:gain ratio, carcass quality and economic viability of using fresh sugar cane and mombaça grass silage in Brangus castrated and intact males on termination. We used 140 Brangus cattle, with an average of 21 months and 355 kg live weight, identified and randomly assigned to treatments: T1, 37 intac males and T2, 37 castrated animals receiving both fresh sugar cane (Saccharum officinarum crushed;T3, 33 intact males and T4, 33 castrated animals, both fed mombaça grass silage (Panicum maximum cv mombaça. For economic evaluation, it was estimated the production costs of bulky coming from the farm costs, expenses concentrates, diesel, hand labor, equipment maintenance and control of 46 Colloquium Agrariae, v. 10, n.1, Jan-Jun. 2014, p.45-54. DOI: 10.5747/ca.2014.v10.n1.a099 parasites were also considered. The final weight of the entire animal was higher (P <0.05 than castrated animals. And feed conversion was higher in castrated animals, indicating that the bulls were more efficient in converting food into weight gain. The higher net revenue observed in intact males (mombaça is justified by the greater weight gain and lower diet costs. Animals that received diet with mombaça grass silage had greater economic feasibility of that received diet with sugar cane.

  1. Effets de Panicum maximum Jacq. associé à Euphorbia heterophylla (L.) Klotz. & Garcke sur la productivité des femelles durant le cycle de reproduction chez le cobaye (Cavia porcellus L.)

    OpenAIRE

    N'G. D.V. Kouakou; Thys, E.; Yapi, YM.; Assidjo, EN.; Marnet, PG.; Grongnet, JF.

    2015-01-01

    Effect of Panicum maximum Jacq. Associated with Euphorbia heterophylla (L.) Klotz. & Garcke on Productivity of Females (Cavia porcellus L) During the Reproductive Cycle. In Ivory Coast, Guinea pigs reared for meat (Cavia porcellus L.) are mainly fed with Panicum maximum Jacq. The association of this forage with Euphorbia heterophylla (L.) Klotz. & Garcke improves the organic matter digestibility of the mixed diet compared to P. maximum distributed alone in growing male guinea pigs. In order t...

  2. Effet de Panicum maximum sur la productivité des femelles primipares durant le cycle de reproduction chez le cobaye (Cavia porcellus L.

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    Danho, M.

    2012-01-01

    Full Text Available Effect of Panicum maximum on Productivity of Primiparous Females during Reproduction Cycle in Guinea Pigs (Cavia porcellus L.. In Ivory Coast, Guinea pigs reared for meat (Cavia porcellus L. are mainly fed with Panicum maximum. To assess the effect of the latter during pregnancy and lactation (RC of these animals, primiparous dams were fed ad libitum, Panicum maximum alone during the RC (MOD1 or associated with pellets for rabbits during lactation (MOD2, or associated with pellets for rabbits during the last part of the pregnancy period and the lactation (MOD3, or associated with pellets for rabbits during the entire RC (MOD4. The number of corpora lutea per female was 1.3 ± 0.5 and 2.0 ± 0.0 respectively for MOD1 and MOD4. No pre-embryonic mortality was recorded. The mean weight of the young guinea pigs of MOD1 (54.7 ± 10. g was only 55% of that of MOD4 (98.6 ± 13.6 g. At weaning, the average weight gain of young guinea pigs of MOD1 (40.5 ± 22.2 g represented a third of those obtained with other diets that did not significantly differ. At the end of RC, the weight gain of dams was 17 ± 13.3% for MOD1 compared to 50% for MOD2, MOD3 and MOD4. Feeding Panicum maximum alone induces chronic malnutrition which in turn is responsible of the low ovulation rate and reduced growth in guinea pig breeding.

  3. PRODUTIVIDADE DE CAPIM-MOMBAÇA (Panicum maximum, COM DIFERENTES DOSES DE BIOFERTILIZANTE / MOMBAÇA GRASS PRODUCTIVITY (Panicum maximum, WITH DIFFERENT DOSES OF BIOFERTILIZER

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    A. Simonetti

    2016-03-01

    Full Text Available O presente estudo teve por objetivo verificar a influência da aplicação do dejeto de bovino leiteiro tratados em biodigestores anaeróbios, na forma de biofertilizante, sobre a produtividade da capim Mombaça, em condições de sequeiro.  O trabalho foi conduzido no Instituto de Biotecnologia – IBIOTEC, pertencente à UNIARA, Araraquara – SP. Para obtenção do biofertilizante, foi feita a diluição dos dejetos em água e armazenado em um biodigestor modelo indiano de fibra de vidro com capacidade útil de 1000 L, instalado no referido instituto. As fertilizações foram feitas a lanço após cada rebaixamento das parcelas. O delineamento utilizado foi em blocos casualizados, com quatro tratamentos e quatro repetições, com diferentes doses do biofertilizante, sendo: 0; 50m³; 100m³ e 200m³/ha-1.  As variáveis avaliadas foram: altura, produção por hectare (matéria seca e matéria verde, e qualidade bromatológica. Foram observados que os tratamentos que receberam a maior dosagem de biofertilizante, apresentaram maiores valores para produtividade Matéria Seca, Matéria Verde e teor de proteína. Conclui-se que a aplicação de biofertilizante é benéfico ao sistema de pastagem, porém suas doses devem ser estudadas e a sua resposta na produção pode obtidas a longo prazo.

  4. Métodos de colheita e qualidade das sementes de capim colonião cultivar Mombaça Effects of harvesting methods on seed quality of Panicum maximum (Jacq. cultivar Mombaça

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    Renata Waldemarin Maschietto

    2003-01-01

    Full Text Available A produção de sementes, em gramíneas forrageiras tropicais como o capim colonião (Panicum maximum Jacq., apresenta particularidades capazes de interferir na pureza física e na germinação das sementes. Por conseqüência, o método de colheita pode influenciar diretamente na qualidade das sementes produzidas. Buscando estudar o assunto, a presente pesquisa utilizou sementes de P. maximum cultivar Mombaça, colhidas pelos métodos (tratamentos do cacho, de varredura e mecanizado, as quais, previamente analisadas quanto à pureza física, foram armazenadas sob condições não controladas de laboratório durante 15 meses. A avaliação da qualidade fisiológica das sementes, realizada trimestralmente em seis épocas, constou da realização dos testes de germinação, de primeira contagem de germinação, de envelhecimento acelerado e de condutividade elétrica. Os resultados indicaram que há influência do método de colheita na qualidade das sementes; o método de varredura permite a obtenção de sementes que, embora de menor pureza física, apresentam maior qualidade fisiológica do que as provenientes dos métodos do cacho e mecânico.The production of higher quality seeds of tropical forage grasses such as guinea grass (Panicum maximum Jacq. presents some details that are able to influence on seed purity and germination. As a consequence, harvest time and method have a direct influence on seed quality. This research was carried out with the main objective of evaluating the quality of guinea grass seeds, cv Mombaça, harvested by three methods: a hand cutting the panicles followed by curing on the ground for three to five days; b hand collecting the shattered seeds from the ground and c mechanical. Seeds obtained from each harvesting procedure, were first evaluated for physical purity and then stored under uncontrolled conditions during 15 months. Germination, vigor (first count, accelerated aging, electrical conductivity were

  5. Timpanismo gastrointestinal em equídeos alimentados com Panicum maximum com alto conteúdo de amido

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    Taciane M. Souza

    Full Text Available RESUMO: Timpanismo intestinal agudo em cavalos e mulas introduzidos em pastagens de Panicum maximum cv. Tanzânia, cv. Massai e cv. Mombaça são relatados na região norte do Brasil, durante o período das chuvas. As causas são desconhecidas, porém, tem sido sugerido que estão associados a um maior armazenamento de carboidratos não fibrosos na gramínea. Este trabalho teve por objetivos realizar um levantamento epidemiológico dos surtos de cólicas ocorridos no Estado de Rondônia, assim como contribuir com o estudo da ação dos carboidratos de P. maximum na ocorrência da doença. Para isso foram realizadas visitas em 10 propriedades que apresentaram casos da enfermidade. Em duas propriedades foram introduzidos equinos no mês de março e foram coletadas amostras de pastagens para a determinação de energia digestiva, lisina, matéria seca, carboidratos solúveis em água, carboidratos solúveis em éter, carboidratos não fibrosos, fibra de detergente neutra, fibra de detergente ácido, lignina, amido, gordura e proteína bruta. Essas determinações foram realizadas, também, em amostras de pastagens de P. maximum de outras propriedades onde não estavam ocorrendo cólicas e das pastagens de Cynodon dactylon de onde provinham os equinos. Os resultados mostraram que os surtos de cólica ocorrem na época de chuva, quando as pastagens estão rebrotando com uma morbidade de 31,6%, e letalidade de 86,1%. As análises bromatológicas mostraram uma diferença significativa nas concentrações de amido (P=0,0072 do P. maximum que causou cólica (8,3 % e 9,2%, quando comparado com o P. maximum das outras propriedades (0,9% e 4,3% e com o Tifton, utilizado previamente na alimentação dos mesmos equinos (0,2% e 0,8%. Em outra fazenda a doença foi reproduzida experimentalmente em um equino, no mês de março administrando P. maximum cortado contendo 6,5% de amido. A mesma pastagem não causou cólica quando foi administrada a equinos entre os

  6. Possibilities for Growing Switch-grass (Panicum virgatum as Second Generation Energy Crop in Dry-subhumid, Semiarid and Arid Regions of the Argentina

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    Silvia FALASCA

    2017-03-01

    Full Text Available Panicum virgatum (swich-grass is cultivated in some countries to obtain biomass used in the production of heat, fiber, electricity and second generation ethanol. Currently, in Argentina, this species is used for forage and as an ornamental. The aim of this work was to design an agroclimatic zoning model for swich-grass in Argentina, both for upland and lowland ecotypes, based on its bioclimatic requirements and employing a Geography Information System. The variables taken into consideration were: average temperature during growing period and reproductive period, frost free days and rainfall during growing season. This work demonstrated that an ample region of the country is agro-climatically suitable for the implantation of switch-grass in rainfed conditions or with complementary irrigation. The agroclimatic zoning for the upland ecotype shows that suitability reaches latitudes of up to 46ºS, while the lowland ecotype can be grown up to 40ºS. Thornthwaite's Moisture Index equal to zero was overlapped to the Argentinean agroclimatic zoning for upland and lowland types, to obtain the potential growing areas under dry-subhumid, semiarid to arid climates. The areas where switch-grass should be effectively tested are those categorized as optimal, very suitable, suitable, and very suitable/suitable with irrigation, located to the West of TMI equal to zero, which include dry-subhumid (0

  7. Comportamiento de 19 accesiones de Panicum maximum Jacq. bajo condiciones de pastoreo en un suelo de mediana fertilidad

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    R Machado

    Full Text Available El objetivo de este trabajo fue determinar el comportamiento de 19 accesiones de Panicum maximum en suelos de mediana fertilidad. Se utilizó un diseño de bloques al azar con tres repeticiones y parcelas de 20 m². Las rotaciones (pastoreo racional simulado se efectuaron entre 60 y 70 días (época de seca y entre 32 y 40 días (época de lluvia. Se detectó una aceptable variabilidad entre tratamientos (70,7 %. Los indicadores más variables fueron: la disponibilidad, el porcentaje de utilización, el porcentaje de hojas y la altura de las plantas. Se aplicó un análisis de conglomerados y se formaron dos grupos: tipos gigantes (grupo 1 y tipos medianos (grupo 2. Los tratamientos del grupo 1 alcanzaron una disponibilidad media de 5,0 t MS/ha/rotación y superaron en 0,7 t MS/ha/rotación a los del grupo 2. Sin embargo, estos últimos mostraron menores síntomas de clorosis (34,0 %, fueron más tolerantes a los microorganismos patógenos (25,0 % y menos afectados por la sequía (42,0 %, y presentaron mayor vigor (3,8 como media de los tres años. Se concluye que en la variabilidad tuvieron un papel fundamental la disponibilidad, la altura, el porcentaje de hojas y el porcentaje de utilización. El resto de los indicadores fue relativamente poco variable, pero también permitió enjuiciar el comportamiento de estos materiales. Se recomiendan los tipos medianos CIH-6, SIH-810 y CIH-22 como variedades precomerciales para condiciones similares a las aquí utilizadas, e incluir el tipo gigante SIH-759 en ensayos en los que se emplee el corte o el pastoreo con mayor intensidad

  8. Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: I. Influencia de su composición química Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: I. Influence of their chemical composition

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    Saray Sánchez

    2009-09-01

    Full Text Available Con el objetivo de determinar la descomposición de la hojarasca y su relación con la composición química de Panicum maximum y Leucaena leucocephala en un sistema silvopastoril, se realizó este experimento en la EEPF "Indio Hatuey". La descomposición de la hojarasca se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags. En cada especie se presentó un patrón diferente de descomposición de la hojarasca; la tasa promedio de descomposición de la hojarasca en leucaena fue mayor que en la guinea. En ambas especies se encontró una rápida pérdida de peso durante los primeros 30 días y después el proceso fue más lento. Este comportamiento puede estar relacionado con la composición química de los pastos, pues el porcentaje de biomasa perdida de la hojarasca de L. leucocephala presentó una mayor correlación con las concentraciones del contenido celular, la relación lignina/nitrógeno, la celulosa y el Nt. Se observó una dependencia significativa y negativa de la hojarasca de P. maximum con las concentraciones de la FND y la hemicelulosa; mientras que se relacionó de forma positiva con las de N-FND y la relación lignina/nitrógenoWith the objective of determining the litter decomposition and its relationship to the chemical composition of Panicum maximum and Leucaena leucocephala in a silvopastoral system, this trial was conducted at the EEPF «Indio Hatuey». Litter decomposition was determined as biomass loss through time, with regards to initial weight. For studying the decomposition dynamics, the method of litter bags was used. In each species a different litter decomposition pattern appeared; the average litter decomposition rate was higher in leucaena than in Guinea grass. Rapid weight loss was found in both species during the first 30 days and afterwards the process was slower

  9. Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: II. Influencia de los factores climáticos Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: II. Influence of climatic factors

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    Saray Sánchez

    2009-12-01

    Full Text Available Con el objetivo de determinar la descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala y su relación con algunos factores del clima, se realizó este experimento en la EEPF «Indio Hatuey». La descomposición de la hojarasca se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags; se registró diariamente el comportamiento de la temperatura media, la humedad relativa, la precipitación y los días con lluvias, en la estación metereológica situada a 1 km del área experimental. Se utilizó el análisis de correlación y regresión para conocer la interrelación entre las variables y los modelos de mejor ajuste. Se consideró, como variables independientes, los factores climáticos estudiados, y como variable dependiente el porcentaje de biomasa perdida. De forma general, los resultados demostraron que el comportamiento de la descomposición de la hojarasca, tanto en la guinea como en la leucaena, estuvo relacionado con los factores climáticos que prevalecieron durante el período experimental y, por tanto, es posible explicar este proceso en ambos pastizales a partir de la acción conjunta de la temperatura, la humedad relativa y la precipitación.With the objective of determining the litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala and its relationship to some climate factors, this trial was conducted at the EEPF «Indio Hatuey». Litter decomposition was determined as the loss of biomass through time, with regards to initial weight. For studying the decomposition dynamics the method of litter bags was used; the performance of mean temperature, relative humidity, rainfall and days with rain, was daily recorded at the meteorological station located 1 km away from the experimental area. . The

  10. Etude comparative de la digestibilité in vivo de l'herbe de guinée (Panicum maximum Jacq. associée aux feuilles et tiges de patate douce (Ipomoea batatas (L. Lam (régime Panipo ou à l'herbe de lait (Euphorbia heterophylla L. (régime Paneuph chez le lapin (Oryctolagus cuniculus L. et le cobaye (Cavia porcellus L.

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    Kouakou, NGDV.

    2016-01-01

    Full Text Available Digestibility of Guinea grass (Panicum maximum Jacq. associated with sweet potato leaves and stems (Ipomoea batatas (L. Lam (Panipo diet or poison milk (Euphorbia heterophylla L. (Paneuph diet in Rabbits (Oryctolagus cuniculus L. and in Guinea Pigs (Cavia porcellus L.. A comparative study of in vivo digestibility of Guinea grass (Panicum maximum Jacq. associated with sweet potato leaves and stems (Ipomoea batatas (L. Lam (Panipo diet or with poison milk (Euphorbia heterophylla L. (Paneuph diet was conducted involving 16 rabbits and 16 weaned guinea pigs fed ad libitum. Paneuph was significantly better ingested (P0.05 for guinea pigs. Poison milk was better ingested than the leaves and stems of sweet potato (P0.05. The ADC of DM, OM and MAT of Paneuph exceeded 80% and were higher than those of Panipo in rabbits and guinea pigs (P<0.05. Based on the results obtained, the effects of the distribution of the Guinea grass associated with the poison milk during rabbits growing have to be further studied before recommending this new diet to farmers in areas where poison milk and Guinea grass are present and rabbit breeding enough developed.

  11. PHOTOSYNTHESIS AND YIELDS OF GRASSES GROWN IN SALINE CONDITION

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    E.D. Purbajanti

    2014-10-01

    Full Text Available The aim of this study was to know effects of saline condition to crop physiology, growth andforages yield. A factorial completed random design was used in this study. The first factor was type ofgrass, these were king grass (Pennisetum hybrid, napier grass (Pennisetum purpureum, panicum grass(Panicum maximum, setaria grass (Setaria sphacelata and star grass (Cynodon plectostachyus. Thesecond factor was salt solution (NaCl with concentration 0, 100, 200 and 300 mM. Parameters of thisexperiment were the percentage of chlorophyll, rate of photosynthesis, number of tiller, biomass and drymatter yield. Data were analyzed by analysis of variance and followed by Duncan’s multiple range testwhen there were significant effects of the treatment. Panicum grass had the highest chlorophyll content(1.85 mg/g of leaf. Photosynthesis rate of setaria grass was the lowest. The increasing of NaClconcentration up to 300 mM NaCl reduced chlorophyll content, rate of photosynthesis, tiller number,biomass yield and dry matter yield. Responses of leaf area, biomass and dry matter yield to salinitywere linear for king, napier, panicum and setaria grasses. In tar grass, the response of leaf area andbiomass ware linear, but those of dry matter yield was quadratic. The response of tiller number tosalinity was linear for all species.

  12. Effect of the populational densities of Panicum maximum (cultivar Tanzânia in phytoremediation of polluted soil with picloram herbicide / Efeito da densidade populacional de Panicum maximum (cultivar Tanzânia na fitorremediação de solo contaminado com o herbicida picloram

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    Leandro Pereira Pacheco

    2009-07-01

    Full Text Available This research was carried out from September of 2006 to February of 2007, under greenhouse conditions, in Rio Verde –GO/ Brazil to study the influence of Panicum maximum populational density on the phytoremediation of soil contaminated with picloram. The treatments were the combination of four Panicum maximum (cultivar Tanzânia populational densities (0, 5, 10 e 15 plants per pot, corresponding to a 0, 122, 244 and 366 plants m-2, respectively and three rates of picloram (0, 80 and 160 g ha-1 applied directly on the pots, simulating levels of soil contamination. After cultivating the phytoremediator specie on substrate during 100 days, soybean Glycine max L was sown at the same pot, used as a phytotoxicity bioindicator specie. Height of plants and green and dry mass of the above ground part of soybean were evaluated. The population density of the phytoremediate species Tanzania influenced the level of phytotoxicity of the herbicide picloram soybean crop sowed in succession. The population density of , 122 plants m-2 was the most efficient in the decontamination of the soil.O objetivo desse trabalho foi avaliar a influência da densidade populacional de Panicum maximum (cultivar Tanzânia sobre a fitorremediação de solo contaminado com o herbicida picloram. O experimento foi conduzido em casa-de-vegetação, de setembro de 2006 a fevereiro de 2007. Os tratamentos foram compostos pela combinação entre quatro densidades populacionais da espécie vegetal Panicum maximum (cultivar Tanzânia (0, 5, 10 e 15 plantas por vaso, equivalentes a 0, 122, 244 e 366 plantas m2, respectivamente e de três doses do picloram (0, 80 e 160 g ha-1 aplicadas diretamente nos vasos, simulando níveis de contaminação do solo. Após o cultivo da espécie fitorremediadora por 100 dias, efetuou-se, no próprio vaso, a semeadura da espécie bioindicadora da presença do picloram, soja (cultivar Monsoy 6101, na qual foram avaliadas a fitotoxicidade, a altura de

  13. Optimización de las condiciones de germinación de cuatro especies de pastos tropicales II Brachiaria humidicola y panicum maximum

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    Carlos Gutiérrez

    2006-05-01

    Full Text Available Se evaluó el efecto de diferentes condiciones ambientales y de sustrato sobre la germinación de semilla de los pastos Brachiaria humidicola y Panicum maximum. Los sustratos evaluados fueron: papel, turba y suelo; las condiciones de temperatura fueron: continua a 30 °C y alterna con 8h a 20 °C y 16 h a 30° C. Se utilizaron diferentes contenidos de humedad en los sustratos: papel saturado, turba con 30, 45 y 60%, y suelo con 10, 20 y 30%. Se evaluó el porcentaje de germinación a los 3, 14 y 22 días, la longitud de la plúmula a los 5 días y el peso seco de las plántulas a los 7 días de la Alizaga3siembra. En P. maximum la temperatura no afectó la germinación, mientras que en B. humidicola la temperatura alterna favoreció un mayor porcentaje de plántulas normales. El mayor peso seco y longitud de plúmula se obtuvo con 30 °C. En B. humidicola el mejor sustrato fue turba y en P. maximum papel. La humedad de la turba no tuvo efecto sobre la germinación, en suelo fue crítica únicamente en P. maximum con 10% de humedad. La menor longitud se alcanzó en P. maximum en papel, mientras que en B. humidicola en suelo.

  14. Uso de efluentes da carcinicultura na irrigação de Panicum maximum cvs. Tanzânia e Mombaça

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    Fábio Rodrigues de Miranda

    Full Text Available Resumo O trabalho objetivou avaliar as alterações químicas do solo e a produção de duas cultivares de capim Panicum maximum Jacq. (Tanzânia e Mombaça, em resposta à irrigação com o efluente da carcinicultura em águas interiores e comparar os resultados com os obtidos com a irrigação convencional, utilizando água de rio. O experimento foi realizado em uma fazenda de criação de camarão, em Russas-CE. Utilizou-se um delineamento experimental de blocos casualizados, em um esquema fatorial 2 (cultivares de capim x 2 (tipos de água utilizada na irrigação. Em quatro cortes do capim foram avaliadas as variáveis de produção: altura, produtividade de matéria seca e porcentagem de matéria seca. Os dados foram submetidos à análise de variância e ao teste de Tukey. Foram analisados, antes e após a aplicação dos tratamentos, os seguintes atributos químicos do solo: pH, condutividade elétrica do extrato saturado (CEes, porcentagem de sódio trocável (PST, matéria orgânica, P, K+, Ca2+, Mg2+ e Na+. Os dados foram submetidos ao teste de t , com nível de significância de 5%. A irrigação com o efluente da carcinicultura não aumentou nem reduziu, significativamente, a produção de matéria seca das duas cultivares de Panicum maximum, em comparação com a irrigação com a água do rio Jaguaribe. Após 14 meses de cultivo, o solo irrigado com o efluente apresentou níveis significativamente maiores (p < 0,05 de Na+, CEes e PST em relação ao solo irrigado com a água do rio Jaguaribe.

  15. Climate, CO2, and the history of North American grasses since the Last Glacial Maximum.

    Science.gov (United States)

    Cotton, Jennifer M; Cerling, Thure E; Hoppe, Kathryn A; Mosier, Thomas M; Still, Christopher J

    2016-03-01

    The spread of C4 grasses in the late Neogene is one of the most important ecological transitions of the Cenozoic, but the primary driver of this global expansion is widely debated. We use the stable carbon isotopic composition (δ(13)C) of bison and mammoth tissues as a proxy for the relative abundance of C3 and C4 vegetation in their grazing habitat to determine climatic and atmospheric CO2 controls on C4 grass distributions from the Last Glacial Maximum (LGM) to the present. We predict the spatial variability of grass δ(13)C in North America using a mean of three different methods of classification and regression tree (CART) machine learning techniques and nine climatic variables. We show that growing season precipitation and temperature are the strongest predictors of all single climate variables. We apply this CART analysis to high-resolution gridded climate data and Coupled Model Intercomparison Project (CMIP5) mean paleoclimate model outputs to produce predictive isotope landscape models ("isoscapes") for the current, mid-Holocene, and LGM average δ(13)C of grass-dominated areas across North America. From the LGM to the present, C4 grass abundances substantially increased in the Great Plains despite concurrent increases in atmospheric CO2. These results suggest that changes in growing season precipitation rather than atmospheric CO2 were critically important in the Neogene expansion of C4 grasses.

  16. Análise de repetibilidade de caracteres forrageiros de genótipos de Panicum maximum, avaliados com e sem restrição solar Repeatability analysis of forage traits of Panicum maximum genotypes evaluated under natural and attenuated solar radiation

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    Alberto Cargnelutti Filho

    2004-06-01

    Full Text Available O objetivo do trabalho foi determinar o número de medições necessárias à predição do desempenho de cinco genótipos de Panicum maximum Jacq. Os genótipos (Gatton, Vencedor, Mombaça, Tanzânia e Tobiatã foram avaliados sob os sistemas de cultivo com e sem restrição solar, na Fundação Estadual de Pesquisa Agropecuária, situada em Tupanciretã - Rio Grande do Sul. No sistema de cultivo com restrição solar, os genótipos foram avaliados sob um bosque de eucalipto. Em cada uma das oito medições (cortes, foram avaliadas a matéria seca total, matéria seca de folhas, matéria seca de colmo, matéria seca folha + colmo, altura de planta e relação matéria seca folha/colmo. As estimativas dos coeficientes de repetibilidade foram obtidas por três métodos - análise da variância, componentes principais e análise estrutural. Concluiu-se que os oito cortes possibilitaram selecionar genótipos superiores em relação a todas as características, com 80% de exatidão no prognóstico de seu valor real.The objective of this study was to determine how many evaluations were necessary to predict the performance of Panicum maximum Jacq. genotypes. The genotypes Gatton, Vencedor, Mombaça, Tanzânia, and Tobiatã were evaluated under natural and attenuated solar radiation at the Fundação Estadual de Pesquisa Agropecuária, Tupanciretã, RS. Attenuated solar radiation was obtained when plants were grown in Eucalyptus woods. Genotypes in both crop systems were evaluated eight times. Total dry matter production, leaf, stem, and leaf plus stem dry matter, plant height and index of leaf and stem dry matter were recorded each evaluation time. Repeatability estimations were obtained through variance, structural, and principal component analysis. In conclusion, eight evaluations permit to select superior Panicum maximum genotypes, considering all characteristics, with 80% accuracy of the real value.

  17. Performance of sheep grazing Brachiaria decumbens, Panicum ...

    African Journals Online (AJOL)

    Performance of sheep grazing Brachiaria decumbens, Panicum maximum and Pennisetum purpureum in combination with gliricidia sepium. ... The animals weregrazed continuously for 28 days in the sub plots. Sheep grazing the Gliricidia/Panicum plot had a higher (P < 001) growth rate (38 g d-1) than those animals ...

  18. Radiosensibility curve with 60 Co in guinea grass (Panicum maximum Jacq.) cv. 'K-249'

    International Nuclear Information System (INIS)

    Lajonchere, G.; Mesa, A.R.; Prieto, M.; Sánchez-Quiroz, E.

    1995-01-01

    In order to select the adequate radiosensibility criterion and useful dosis were studied the effects of gamma radiation on the embryogenic callus of guinea cv. K-249. The application dosages were 0, 10, 20, 40, 60, 80, 100, 150, 200, 250, 300 and 400 Gy and the measures evaluated were: increase of fresh mass of the callus in fresh medium, number of shoots, plantlets and total by callus and by gram of callus in regeneration medium. It was determined that the curves shaped with the number of shoots, plantlets and total by callus and by gram of callus were more radiosensible than that shoped with increase of fresh mass of the callus; as criterion of radiosensibility in this cultivar the total number of shoots and plantlets from gram of callus was selected for it's simplicity and veracity as much as in the evaluation and in the results. The useful dosis that determined one GR 10, 20, 50 and 70 percent were 16, 20, 29 and 160 Gy respectively. Albino shoots were also observed whose values were randomizely showed and it was observed albinism in 0 dosis. (author) [es

  19. Beef cattle supplementation maintained on pasture of “Panicum maximum” cv. Tanzânia-1 on rainy season Suplementação de bovinos de corte mantidos em pastagem de "Panicum maximum" cv. Tanzânia-1 no período das águas

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    João Garcia Caramori Júnior

    2008-06-01

    Full Text Available The objective with this study was to evaluate the effect of different supplementation levels in Nelore bulls during rainy season. It was used 32 Nelore bulls with 18 months old and 374 Kg of body live weight (LW, which were submitted to one of the four treatments: T1, pasture with mineral salt; T2, pasture plus 0.2% of LW of concentrate ration; T3, pasture plus 0.4% of LW with concentrate ration; T4, pasture plus 0.6% of LW with concentrate ration. Animals were kept on pastures of Panicum maximum cv. Tanzânia-1 divided in four fields with 3 hectares, for each group. Supplements were constituted of mineral salt, corn meal, soybean meal, soybean hulls and urea. Animals were weighed at the beginning and every 28 days to determinate average daily weight gain (ADG, and kept under rotational grazing and pasture mass availability was evaluated. ADG was not influenced by the levels of supplement. The use of Tanzania grass with adequate mass pasture availability allowed higher performance of the beef cattle in rainy season, that presented ADG of 0.99kg/animal.Objetivou-se com este trabalho avaliar o efeito de diferentes níveis de suplementação sobre o desempenho de touros Nelore PO, durante o período das águas. Foram utilizados 32 animais de 18 meses de idade, com peso vivo médio inicial de 374 Kg, os quais foram divididos em quatro grupos e submetidos aos seguintes tratamentos experimentais avaliados: mistura mineral (T1; suplementação com concentrado na base de 0,2% do peso vivo (T2; suplementação com concentrado de 0,4% do PV (T3 e suplementação com concentrado de 0,6% do PV (T4. Os animais foram mantidos durante 84 dias em pastagem de Panicum maximum cv. Tanzânia -1, dividida em quatro piquetes de 3 ha , de modo que cada um dos grupos de animais fosse mantido de acordo com o tratamento utilizado. O concentrado foi composto de mistura mineral, fubá de milho, farelo de soja, casca de soja e uréia. Os animais foram pesados no início e a

  20. Influência do oeríodo de cultivo de Panicum maximum (cultivar Tanzânia na fitorremediação de solo contaminado com picloram Influence of Panicum maximum cultivation period on phytoremediation of soil contaminated with picloram

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    M.L. Carmo

    2008-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência do tempo de cultivo de Panicum maximum (cultivar Tanzânia sobre a fitorremediação de solo contaminado com picloram. O experimento foi conduzido em casa de vegetação no período de setembro de 2006 a fevereiro de 2007. Os fatores foram compostos pela combinação entre quatro períodos de cultivo da espécie vegetal Panicum maximum (cultivar Tanzânia (0, 60, 80 e 100 dias e três doses do picloram (0, 80 e 160 g ha-1, totalizando 12 tratamentos. O delineamento experimental utilizado foi o inteiramente casualizado em esquema fatorial 4 x 3, com quatro repetições. Como substrato utilizaram-se amostras de solo classificado como Latossolo Vermelho eutroférrico. Após o tempo estabelecido de atuação da espécie fitorremediadora, efetuou-se a semeadura das espécies bioindicadoras da presença do picloram: tomate e soja. As espécies bioindicadoras demonstraram alta sensibilidade à presença do picloram no solo, sendo inviável o cultivo dessas culturas em áreas contaminadas com esse herbicida sem a execução de algum procedimento remediador. O cultivo prévio de Tanzânia por 60 dias garantiu crescimento inicial satisfatório das plantas de soja e tomate quando a contaminação inicial não foi maior que 80 g ha-1 de picloram. Acima desse valor, a fitorremediação ocorrida proporcionou menor crescimento das plantas de soja e tomate, sendo necessário maior tempo de descontaminação.The objective of this study was to evaluate the influence of cultivation time of Panicum maximum (cv. Tanzania on phyto-remediation of soil contaminated with picloram. The experiment was carried out under greenhouse conditions from September 2006 to February 2007, using euthroferric Red Latosol samples as substrate for plant growth. The experiment was arranged in a completely randomized design, with four replicates, with treatments in a 4 x 3 factorial scheme. The treatments comprised twelve combinations of

  1. Imbalanced carbon-for-phosphorus exchange between European arbuscular mycorrhizal fungi and non-native Panicum grasses-A case of dysfunctional symbiosis

    Czech Academy of Sciences Publication Activity Database

    Řezáčová, Veronika; Slavíková, Renata; Konvalinková, Tereza; Hujslová, Martina; Gryndlerová, Hana; Gryndler, Milan; Püschel, David; Jansa, Jan

    2017-01-01

    Roč. 62, May 2017 (2017), s. 48-55 ISSN 0031-4056 R&D Projects: GA MŠk(CZ) LK11224; GA ČR(CZ) GA14-19191S Grant - others:AV ČR(CZ) Fellowship J. E. Purkyně Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhiza * Panicum * Plant biomass Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.000, year: 2016

  2. Effets de Panicum maximum Jacq. associé à Euphorbia heterophylla (L. Klotz. & Garcke sur la productivité des femelles durant le cycle de reproduction chez le cobaye (Cavia porcellus L.

    Directory of Open Access Journals (Sweden)

    N'G. D.V. Kouakou

    2015-01-01

    Full Text Available Effect of Panicum maximum Jacq. Associated with Euphorbia heterophylla (L. Klotz. & Garcke on Productivity of Females (Cavia porcellus L During the Reproductive Cycle. In Ivory Coast, Guinea pigs reared for meat (Cavia porcellus L. are mainly fed with Panicum maximum Jacq. The association of this forage with Euphorbia heterophylla (L. Klotz. & Garcke improves the organic matter digestibility of the mixed diet compared to P. maximum distributed alone in growing male guinea pigs. In order to determine the effect of this diet during gestation and lactation in female guinea pigs, three diets: P. maximum (PAN basic diet; P. maximum associated to E. heterophylla (PANEUPH and P. maximum associated to pellets for rabbit (PANGRAN, were distributed ad libitum to multiparous guinea pigs (604.9 ± 40.8 g. The daily ingestion during gestation and lactation were 59.8±11.2 and 53.2±8.5; 61.5±5.2 and 72.9±16.4; 83.1±12.9 and 111.3±13.9 g DM.d-1 respectively for PAN, PANEUPH and PANGRAN. Similarly, the rates of fecundity were 111.1±0.9; 188.9±0.6 and 244.4±0.5% respectively for PAN, PANEUPH and PANGRAN. The individual birth weight and weight gain during lactation of the piglets were 58.7±12.4, 75.6±16.2 and 102.5±12 g and 2.4±0.6; 4.1±0.9 and 6.5±1.2 g.d-1 respectively for PAN, PANEUPH, and PANGRAN. In conclusion, the association of P. maximum and E. heterophylla significantly improves ingestion, digestibility, fecundity, birth weight and weaning weight in guinea pigs in comparison to Panicum maximum used as a sole diet.

  3. COMPOSIÇÃO QUÍMICA DO CAPIM-MOMBAÇA (Panicum maximum Jacq. SUBMETIDO À ADUBAÇÃO ORGÂNICA E MINERAL

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    KARINA ROCHA FREITAS

    2011-09-01

    Full Text Available The objective of this study was to evaluate the chemical composition of Panicum maximum Jacq. fertilized with pig slurry (PS and mineral fertilizer during the rainy season for two consecutive years. The experiment was conducted from October 2004 to March 2005 and fromSeptember 2005 to April 2006. The following treatments were used: Witness=replacement of 3.5 kg/ha of P2O5 and 18 kg/ha of K2O/t of dry matter of forage; TQ=replacement of 3.5 kg/ha of P2O5, 18 kg/ha of K2O/t of dry matter of forage and 300 kg of N/ha/year; T100=100 m3/ha/year of LPW; T150=150 m3/ha/year of LPW; T200=200 m3/ha/year of LPW. The fertilizations were parceled out by the number of cuttings accomplished every year and applied after each cut. The cuttings wereaccomplished every 28 days at 0.30 m of the soil. Macromineral (N, P, K, S, Ca, Mg and microminerals (Cu, Fe, Zn e Mn were assessed in each evaluated period. The experimental design was split-plot random blocks, constituted by the fertilization treatments and by the yearsof evaluation. The chemical composition was influenced by the fertilization with LPW and mineral, as well as by the years of evaluation. The use of 200 m3/ha/ano dose of DLS is recommended.

  4. Avaliação dos capins mombaça e massai sob pastejo Evaluation of Panicum maximum cvs Mombaça and Massai under grazing

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    Valéria Pacheco Batista Euclides

    2008-01-01

    Full Text Available Visando à liberação para uso comercial, realizou-se avaliação do capim-massai (Panicum maximum quanto à adaptação e produtividade. No plantio foram utilizados 2,7 t/ha de calcário dolomítico, 500 kg/ha da fórmula 0-20-15 e 50 kg/ha de FTE BR-12. Como adubação de cobertura, efetuaram-se aplicações da fórmula 0-20-20 (200 kg/ha e de nitrogênio (50 kg/ha de N. Os cultivares testados foram Mombaça e Massai. O delineamento experimental foi o de blocos casualizados com dois tratamentos e duas repetições. Os piquetes (1,5 ha foram subdivididos em seis e submetidos ao pastejo rotacionado, com sete dias de utilização e 35 dias de descanso. Foram utilizados quatro animais-teste por piquete e animais reguladores para manter resíduos de MS pós-pastejo superiores a 2 t/ha. Os pastos foram amostrados no pré e no pós-pastejo para se estimarem a massa de forragem, a proporção dos componentes morfológicos e o valor nutritivo. Os animais foram pesados a cada 42 dias. Os animais no pasto de capim-mombaça ganharam mais peso (437 g/novilho.dia que aqueles no pasto de capim-massai (300 g/novilho.dia. No entanto, o capim-massai suportou maior taxa de lotação (2,15 UA/ha que o capim-mombaça (1,86 UA/ha. No entanto, esta maior capacidade de suporte não foi suficiente para compensar o menor ganho de peso vivo dos animais neste pasto (626 kg/ha.ano em comparação àqueles mantidos no pasto de capim-mombaça (691 kg/ha.ano. O desempenho satisfatório, associado a outras importantes características de adaptação, torna o cultivar Massai uma forrageira promissora para a diversificação e viabilização da sustentabilidade de sistema de produção de bovinos de corte.A new cultivar of Panicum maximum (Massai was evaluated for commercial release, at the Embrapa Beef Cattle, Campo Grande, MS, Brazil, from November 1993 to April 1999. At establishment, 2,7 t/ha of lime, 400 kg/ha of 0-20-20 and 50 kg/ha of FTE were applied. Maintenance

  5. Fatores limitantes ao crescimento do capim-Tanzânia em um sistema agrossilvipastoril com eucalipto, na região dos Cerrados de Minas Gerais Factors limiting the growth of Panicum maximum cv. Tanzânia-1 in an agrosilvopastoral system with eucalypt, in the Cerrados of Minas Gerais, Brazil

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    Carlos Mauricio Soares de Andrade

    2001-07-01

    Full Text Available Conduziu-se um estudo em um sistema agrossilvipastoril, constituído por Eucalyptus urophylla e Panicum maximum cv. Tanzânia-1, para verificar a hipótese de que existiam outros fatores, além da baixa disponibilidade de luz, interferindo no crescimento normal da gramínea, quatro anos após sua introdução no sistema. O estudo consistiu de um ensaio de adubação NPK a campo, adotando-se o delineamento experimental de blocos casualizados, com os tratamentos dispostos no arranjo fatorial 2³, com duas doses de nitrogênio (0 e 100 kg/ha de N, fósforo (0 e 70 kg/ha de P2O5 e potássio (0 e 100 kg/ha de K2O. A gramínea não respondeu ao P nem ao K, embora os teores originais de P e K disponíveis no solo fossem baixos. A adubação nitrogenada dobrou a taxa de acumulação de matéria seca do sub-bosque, mostrando que o crescimento da gramínea estava sendo restringido pela baixa disponibilidade de N no solo. A elevada resposta à adubação nitrogenada mostrou que o sombreamento não era o único fator limitando a produtividade do sub-bosque, e, também, que as plantas estabelecidas do capim-tanzânia não estavam sendo afetadas negativa e significativamente por substâncias alelopáticas produzidas pelo eucalipto.A study was conducted in an agrosilvopastoral system, constituted by Eucalyptus urophylla and Panicum maximum cv. Tanzânia-1, to verify the hypothesis that there were other factors, besides the low light availability, affecting the normal growth of the grass, four years after its introduction in the system. A NPK fertilization field trial was carry out, using the randomized block design, with the treatments in the 2³ factorial outline, with two doses of nitrogen (0 and 100 kg/ha of N, phosphorus (0 and 70 kg/ha of P2O5 and potassium (0 and 100 kg/ha of K2O. The grass did not respond to P nor K fertilization, in spite of the low original P and K availability in the soil. However, with the application of nitrogen the rate of herbage

  6. Avaliação de três cultivares de Panicum maximum Jacq. sob pastejo: composição da dieta, consumo de matéria seca e ganho de peso animal Evaluation of three varieties of Panicum maximum Jacq. under grazing: diet composition, dry matter intake and animal weight gain

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    Patrícia Amarante Brâncio

    2003-10-01

    Full Text Available Três cultivares de Panicum maximum Jacq. submetidos a pastejo rotativo foram avaliados ao longo do ano, antes e após o período de pastejo, quanto à composição botânica e química da dieta, consumo de matéria seca e ganho de peso animal. Os tratamentos constituíram em: 1 cv. Tanzânia + 50 kg/ha de N, 2 cv. Tanzânia + 100 kg/ha de N, 3 cv. Mombaça + 50 kg/ha de N, e 4 cv. Massai + 50 kg/ha de N. As dietas selecionadas pelos animais na cv. Massai tenderam a apresentar os menores valores de digestibilidade e proteína bruta e os maiores de fibra em detergente neutro, enquanto na cv. Mombaça as dietas continham, em geral, maiores teores de sílica. Os animais selecionaram, em média, 92,4% de folhas verdes, independentemente do tratamento e da época de amostragem. Os animais consumiram semelhantes quantidades de forragem nos diversos tratamentos, apresentando, em média, consumos de 1,9; 2,8; 3,4; e 2,3 kgMS/100kgPV, respectivamente, em junho, setembro e novembro de 1998 e março de 1999. Os piores resultados quanto ao ganho de peso por animal foram verificados na cv. Massai, mas, devido a sua alta capacidade de suporte na época chuvosa, superou a cv. Mombaça e cv. Tanzânia + 50 kg/ha de N, em termos de ganho de peso por área. A participação de folhas, a altura do pasto, o teor de proteína bruta da dieta selecionada pelos animais e o tamanho de bocado foram os fatores que mais influenciaram positivamente o ganho de peso animal.Three varieties of Panicum maximum Jacq. were evaluated by measuring the botanical and chemical composition of the diet, and the dry matter intake and weight gain of the animal under rotational grazing, before and after a period of grazing. The treatments were: 1 v. Tanzânia + 50 kg N/ha, 2 v. Tanzânia + 100 kg N/ha, 3 v. Mombaça + 50 kg N/ha, and 4 v. Massai + 50 kg N/ha. Of the diets selected by the animals, v. Massai tended to show lower values for digestibility and crude protein, and higher values

  7. Descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham: III. Influencia de la densidad y diversidad de la macrofauna asociada Litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham: III. Influence of density and diversity of the associated macrofauna

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    Saray Sánchez

    2010-03-01

    Full Text Available Con el objetivo de determinar la descomposición de la hojarasca en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala y su relación con la densidad y la diversidad de la macrofauna asociada, se realizó este experimento en la EEPF «Indio Hatuey». Esta se determinó como la pérdida de biomasa a través del tiempo, con relación al peso inicial. Para el estudio de la dinámica de la descomposición se utilizó el método de bolsas de hojarasca (litter bags. Se escogieron al azar cuatro bolsas a los 30, 60, 90, 120, 150, 180 y 210 días de situadas en el pastizal. En cada fecha de recolección, a la hojarasca remanente de cada bolsa se le determinó la población de macrofauna (organismos con diámetro mayor que 2 mm mediante la separación manual, y se calculó el valor promedio de la densidad (individuos/m², así como la abundancia proporcional (% para cada taxón. Se utilizó el análisis de correlación y regresión para conocer la interrelación entre las variables y los modelos de mejor ajuste. De acuerdo con los resultados se concluye que las condiciones de humedad y temperatura que genera el árbol en este sistema, así como la calidad de su hojarasca, posibilitan la presencia de una diversa y estable fauna asociada a las bolsas, la cual influyó en el proceso de descomposición.The trial was conducted at the EEPF «Indio Hatuey» in order to determine the litter decomposition in a silvopastoral system of Panicum maximum and Leucaena leucocephala and its relation to the density and diversity of the associated macrofauna. It was determined as biomass loss through time, with regards to initial weight. For the study of the decomposition dynamics the litter bag method was used. Four bags were randomly chosen 30, 60, 90, 120, 150, 180 and 210 days after being placed in the pastureland. In each collection date, to the remnant litter of each bag, the macrofauna (organisms with diameter higher than 2 mm population was

  8. Avaliação de Três Cultivares de Panicum maximum Jacq. sob Pastejo: Composição Química e Digestibilidade da Forragem Evaluation of Three Cultivars of Panicum Maximum Jacq. under Grazing: Chemical Composition and in Vitro Organic Matter Digestibility

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    Patrícia Amarante Brâncio

    2002-07-01

    Full Text Available O estudo foi conduzido com o objetivo de estimar o valor nutritivo da MS de três cultivares de Panicum maximum Jacq. submetidas ao pastejo rotativo, através dos teores de proteína bruta, fibra em detergente neutro, fibra em detergente ácido, lignina, celulose, sílica e digestibilidade in vitro da matéria orgânica em amostras de folhas e colmos. Estudou-se, também, no cultivar Tanzânia, a adubação nitrogenada no final do período chuvoso, adicional à de manutenção comum às demais cultivares. As amostragens foram realizadas em junho, setembro e novembro de 1998 e março de 1999. Algumas diferenças entre tratamentos foram observadas, apresentando, em geral, menor valor nutritivo no cv. Massai, com menores teores de proteína bruta e digestibilidade e maiores teores de fibra em detergente neutro, fibra em detergente ácido e lignina tanto nas folhas, como nos colmos. Sua utilização como opção forrageira deve basear-se em outras características agronômicas. O cv. Mombaça apresentou, em geral, maiores teores de sílica e seu valor nutritivo não foi afetado pela adubação nitrogenada no final do período chuvoso, exceto pelo aumento no teor de proteína bruta e pela redução do conteúdo de lignina e sílica em março. O valor nutritivo dos colmos foi inferior ao das folhas. O início do período chuvoso foi, em geral, a época de maior valor nutritivo da forragem em todos os tratamentos.A study was conducted to evaluate three cultivars of Panicum maximum Jacq. under rotational grazing for the nutritive value,where the estimates of crude protein, neutral detergent fiber, acid detergent fiber, lignin, cellulose, silica, and in vitro digestibility of the organic material were performed in samples of leaves and stems. Additional nitrogen was applied in cv. Tanzania at the end of the rainny season. Samples were taken in June, September, and October 1998 and in March 1999. Some differences among treatments were observed. In general

  9. Cambios en la estructura, la población y la composición de 19 accesiones de Panicum maximum sometidas a pastoreo CIAT-184 Changes in the structure, population and composition of 19 Panicum maximum accessions under grazing conditions

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    R Machado

    2012-06-01

    Full Text Available Este trabajo tuvo como objetivo caracterizar los cambios y la tendencia de indicadores relacionados con la estructura, la población y la composición en 19 accesiones de Panicum maximum cuando fueron sometidas a condiciones de pastoreo simulado. Las rotaciones se hicieron cada 32-40 días en el periodo lluvioso y 60-70 días en el poco lluvioso, con intensidad de pastoreo de 80-135 UGM/ha/día (los dos primeros años y 120-160 UGM/ha/día (tercer año. Se utilizó un diseño de bloques al azar con tres repeticiones. Aunque en todos los tratamientos disminuyó la relación vástagos vivos/vástagos muertos, este cociente fue superior a uno, por lo que el ritmo de sustitución de vástagos fue favorable. En el 84,2% de los tratamientos se incrementó el número de macollas con relación a el estatus inicial. El porcentaje de arvenses aumentó con las rotaciones, pero ninguno de los tratamientos alcanzó un estado de deterioro avanzado. En este indicador se destacaron los tipos gigantes CIH-13, SIH-697, CIH-3, CC-1146 y SIH-10, con valores que variaron entre 4,6 y 14,1%, así como los tipos medianos CIH-15 y Tardío pequeño, con 10 y 12,3%, respectivamente. Se concluye que el germoplasma evaluado mostró valores adecuados, en función de los indicadores relacionados con la estructura de la macolla, la población y el porcentaje de invasión de las especies arvenses, aunque se identificó un alto contraste entre los tipos gigantes y medianos y dentro de estos grupos. Se sugiere analizar el resto de los indicadores productivos y con ello determinar los tipos más sobresalientes, sobre la base de los resultados en todos los indicadores incluidos.The objective of this work was to characterize the changes and trend of indicators related to the structure, population and composition in 19 Panicum maximum accessions under simulated grazing conditions. The rotations took place every 32-40 days in the rainy season and 60-70 days in the dry season, with

  10. Among and within family selection and combined half-sib family selection in Panicum maximum Jacq. Seleção entre e dentro de famílias e seleção combinada em famílias de meio-irmãos de Panicum maximum Jacq.

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    Janaina Azevedo Martuscello

    2009-10-01

    Full Text Available The objective of this study was to select superior genotypes in half-sib populations obtained from crosses between sexual plants and apomictic accessions. The experiment also proposed to compare among and within family and combined selection strategies. Ten plots of sexual plants were randomly distributed among 230 plots of apomictic accessions. After natural pollination, seeds of each sexual plant constituted a half-sib family. Thirty plants of each female progenitor were evaluated in a randomized block design experiment, with five plants per plot and five replications. Five evaluation harvests were made in the rainy seasons and two in the dry seasons of all plants. The production and quality characteristics were evaluated. The selection criteria used was: among and within family selection and combined selection with 50% selection in both. The selection criteria used (among and within family selection and combined selection, were efficient for use in P. maximum breeding, with medium to high gains for most characteristics evaluated. The highest genetic gains were obtained from combined selection. However, among and within family selection promoted high genetic gains and may be used in P. maximum breeding. The sexual progenitors identified as numbers 7, 1, 3 and 5 were promising and may be used in future crosses, as well as to increase the genetic variability in the P.maximum genebank.O experimento foi conduzido objetivando-se selecionar genótipos e genitores superiores de Panicum maximum em populações de meio-irmãos, originárias do cruzamento de plantas sexuais com plantas apomíticas, bem como comparar estratégias de seleção entre e dentro de famílias e seleção combinada. Dez parcelas de plantas sexuais de P. maximum foram aleatoriamente distribuídas entre 230 parcelas de acessos apomíticos. Após a fecundação natural, sementes de cada planta sexual constituíram-se uma família de meio-irmãos. Trinta plantas de cada genitora

  11. Produção e composição químico-bromatológica do capim-furachão (Panicum repens L. sob adubação e diferentes idades de corte Production and chemical composition of furachão grass (Panicum repens L. under fertilization and different cutting ages

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    Rogério da Silva Aguiar

    2000-04-01

    Full Text Available O objetivo deste trabalho foi avaliar a produção de matéria seca (MS e a composição químico-bromatológica do capim-furachão (Panicum repens L. em diferentes idades de corte (15, 30, 45, 60 e 75 dias, na presença e ausência de adubação. Para as análises de produção e composição química, utilizou-se delineamento em blocos casualizados, em um fatorial 5 x 2 (cinco idades de corte e dois níveis de adubação, com três repetições. A adubação proporcionou aumento na produção e redução nos teores de MS. Os teores de proteína bruta (PB foram reduzidos com o avanço da idade da gramínea. Aos 60 dias, encontraram-se produções de 541,87 kg/ha de PB e 5343,92 kg/ha de MS e teores médios de FDN e FDA de 69,70 e 34,25% na MS, respectivamente. As idades de corte influíram nos teores de FDN e FDA, mas a adubação não influenciou os teores de FDN. Os teores de Ca não diferiram na presença ou ausência de adubação, com média de 0,13% na MS, e aumentaram com a idade de corte. Os teores de P diminuíram com o avanço da idade da gramínea, sendo o maior valor 0,22% na MS, na condição sem adubo.The objective of this work was to evaluate the dry matter (DM yield and chemical composition of furachão grass (Panicum repens L. at different cutting ages (15, 30, 45, 60 and 75 days, with and without fertilization. For the yield analysis and chemical aanalysis composition, a completely randomized block design in a 5 x 2 factorial arrangement (cutting ages and fertilization levels, with three replicates, was used. Fertilization increased DM produced and reduction in the DM contents. The crude protein (CP contents decreased as the cutting ages increased. At 60 days, productions of 541,87 kg/ha CP and 5343.92 kg/ha DM and average neutral detergent fiber (NDF and acid detergent fiber (ADF contents of 69.7 and basis 34.25% in DM respectively were observed. The cutting ages affected the NDF and ADF average contents, but fertilization

  12. Efecto residual de dos rocas fosfóricas puras y parcialmente aciduladas, comparadas con SFT, sobre la aprovechabilidad del P por Panicum maximum L., en un oxisol de los Llanos Orientales de Colombia

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    Alejo M. Doris

    1986-03-01

    Full Text Available Panicum maximum L. se sembró, en condiciones de invernadero, en un Oxisol de los Llanos Orientales de Colombia, 18 meses después de la aplicación de las fuentes (rocas fosfóricas de Pesca - Colombia y Sechura - Perú crudas y aciduladas al 20 % con H3 P04, en dosis de 25, 50 Y 100 ppm de P. La roca fosfórica Sechura cruda y parcialmente acidulada junto con SFT, tuvieron el mejor efecto residual sobre el rendimiento y captación de P y mantuvieron los más altos niveles de P asimilable en el suelo al final del ensayo. Con las dosis superiores se obtuvo un nivel más alto de P asimilable en el suelo y mayor absorción de P por la planta.In order to study the residual effect of the Pesca (Colombia and Sechura (Perú phosphate rocks, both crude and acidulated in 20 % by H3P04, comparatively with SFT, Panicum rnaximum L. was planted under glasshouse conditions, in an Oxisol from the Eastern plains of Colombia, 18 months after sources application, with rates of 25. 50 and 100 ppm of P. Crude and partially acidulated Sechura phosphate rock, together with TSP, had the best residual effect on yield and P absorption and had the highest available P levels in the soil at the end of the trial. The highest available P level in the soil and P uptake by the plant was obtained with higher P rates.

  13. Características morfogênicas do capim-mombaça (Panicum maximum Jacq. cv. Mombaça adubado com fontes de fósforo, sob pastejo Morphogenic characteristics of mombaçagrass (Panicum maximum Jacq.cv. Mombaça fertilized with phosphorus sources, under grazing

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    Ulysses Cecato

    2007-12-01

    grazing return rate (GRR on mombaçagrass (Panicum maximum Jacq. cv. Mombaça. The experimental design was randomized blocks with three replications. There was no difference between phosphorus sources in all evaluated variables, except for leaf elongation rate, which was higher in tillers fertilized with the SPS+TSP treatment. Differences were found between evaluation periods, with summer showing higher leaf elongation rate and ligule height (first and last. The days evaluated indicated effect on first ligule height (FLH; LLH, number of expanded leaves (NEL, number of leaves in expansion (NFE, total number of leaves (TNL, total number of live leaves (TNLL, total number of senescent leaves (TLS, and grazing return rate (GRR. For days and period interactions only TNLL and TSL had positive linear correlations.

  14. Macronutrients leaf contents of corn in intercropping with forages of genus Panicum and Urochloa in simultaneous seeding

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    Denise Tsuzukibashi

    2013-12-01

    Full Text Available The planting of crops in degraded pasture areas is a formula used for decades by farmers to recover the productive capacity of pastures and soils. The integrated crop-livestock (ICL consists of different production systems of grains, fibers, wood, meat, milk and agro-deployed in the same area, in intercrop, rotation or succession. Typically this integration mainly involves the planting of grain and pasture in the recovery or deployment. This work aimed to evaluate the macronutrients leaf contents of irrigated corn intercropped with forages of the genus Panicum and Urochloa simultaneously to sown corn. The experiment was conducted at the Farm for Teaching, Research and Extension, Faculty of Engineering - UNESP, Ilha Solteira in an Oxisol in Savannah conditions, in experimental area that had a history of no-tillage to 8 years (previous crop corn. The experimental design used was randomized blocks with four replications and five treatments: Panicum maximum cv. Tanzania sown simultaneously (CTS corn; Panicum maximum cv. Mombaça sown simultaneously (CMS to corn; Urochloa brizantha cv. Xaraes sown simultaneously (CBS corn; Urochloa ruziziensis sown simultaneously (CRS to corn, and corn without intercropping (CWI. The seeds of grasses were sown in spacing of 0.34 m, being sown with a seed drill with disc coulters mounted mechanism for no-tillage system at a depth of 0.03 m. There was no significant difference between the single corn tillage and intercropping with different modalities of forage genus Panicum and Urochloa to the leaf contents of N, P, K, Ca and Mg, demonstrating the non-compete forages with corn in a intercrop on the absorption of these nutrients. In respect to S, CTS presented higher content of S foliar when compared to CWI (Table 1. The absorption of nutrients by corn are not affect by the intercrop with forages of the genus Panicum and Urochloa, in simultaneously sown.

  15. Chemical composition and photosynthetically active radiation of forage grasses under irrigation

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    Edilane Aparecida da Silva

    2012-03-01

    Full Text Available The present study aimed to estimate the photosynthetically active radiation of tropical forage grasses in ten cutting dates, under irrigation. The following treatments were used: Brachiaria decumbens grass (Brachiaria decumbens cultivar Basilisk, Marandu grass (Brachiaria brizantha cultivar Marandu, Xaraes grass (Brachiaria brizantha, cultivar Xaraes, Mombaça grass (Panicum maximum cultivar Mombaça, Tanzania grass (Panicum maximum, cultivar Tanzania and Tifton 85 grass (Cynodon spp cultivar Tifton 85. The weather parameters were collected by an automatic meteorological station installed in the location and used for irrigation management. The experiment was arranged in a split-plot completely randomized block design, considering the grasses as plots and cutting seasons as subplots, with four replications in a 6 × 10 factorial arrangement, six grasses and ten cutting seasons. The results indicated increased use of photosynthetically active radiation in the wet season, in relation to the dry-wet season transition. Basilisk presented the highest values of photosynthetically active radiation (1,648.9 mE. The variables studied were affected by photosynthetically active radiation. The grass cultivars presented different light interceptions. The values of 87; 90; 90; 88; 92 and 77% were found for grass cultivars Basilisk, Marandu, Mombaça, Tanzania, Xaraes and Tifton 85, respectively. Differences were observed in forage accumulation rates for the grass plants studied. The grasses with the best productive performance were Brachiaria decumbens cultivar Basilisk and B. brizantha cultivar Xaraes. The highest values of crude protein and neutral detergent fiber were observed for Tifton 85. The use of photosynthetically active radiation was different among the grasses evaluated. There is a positive association between photosynthetically active radiation and dry matter production. Besides, photosynthetically active radiation indirectly affects crude protein

  16. Breaking seed dormancy of switchgrass (Panicum virgatum L.): A review

    Science.gov (United States)

    Switchgrass (Panicum virgatum L.) is a perennial warm-season grass identified as a model species for bioenergy feedstock. Established switchgrass stand are very resilient to environmental fluctuations, however, seed dormancy and weak seedling vigor make establishment difficult. Seeds with high leve...

  17. INTERAÇÃO DO CALCÁRIO E DO SILICATO DE CÁLCIO E MAGNÉSIO COM GESSO AGRÍCOLA NO DESENVOLVIMENTO RADICULAR DE Panicum maximum JACQ. CV. CAPIM MOMBAÇA

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    Vinícius Faúla Aguiar

    2017-01-01

    Full Text Available O objetivo do trabalho é avaliar o efeito das correções do solo efetuadas com calcário e silicato de cálcio e magnésio no desenvolvimento radicular de Panicum maximum Jacq. Cultivar capim Mombaça. Foi adotado delineamento experimental em blocos ao acaso, em esquema fatorial 2x5, sendo estudado em quatro blocos o efeito de duas fontes de corretivo e cinco métodos de aplicação, além da testemunha. Nas análises onde foi observada significância estatística, realizou-se teste de Tukey a 5,0% de probabilidade. A unidade experimental é constituída por colunas de tubos de PVC de 15 centímetros de diâmetro por 60 cm de altura, dividida em seis anéis de 10 centímetros, totalizando 44 unidades. Depois de secas em estufa com circulação forçada de ar a 65 ºC até atingir peso constante as raízes foram pesadas em balança de precisão. O T2 resultou em maior incremento de massa seca. O crescimento radicular na faixa de 0 a 20 cm se mostrou superior às faixas de 20 a 40 e 40 a 60 cm.

  18. Ação do flúor dissolvido em chuva simulada sobre a estrutura foliar de Panicum maximum jacq. (colonião e Chloris gayana kunth. (capim-rhodes - Poaceae

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    Chaves Alba Lucilvânia Fonseca

    2002-01-01

    Full Text Available Panicum maximum e Chloris gayana foram submetidas à chuvas simuladas com soluções de fluoreto de potássio (15mg ml-1 com objetivo de identificar as injúrias causadas pelo flúor (F-, como poluente atmosférico, na estrutura da lâmina foliar e fornecer subsídios para a seleção de características diagnósticas a serem utilizadas na bioindicação. Os principais sintomas foram clorose e necrose, principalmente no ápice e margens das lâminas. Nos cortes transversais, quatro tipos de alterações causadas pelo flúor são relacionadas: redução do número, tamanho e arranjo dos cloroplastos; necrose dos tecidos principalmente nas margens das folhas; erosões na superfície da folha e hipertrofia das células. Em C. gayana, no entanto, não foram observadas as alterações nos cloroplastos e os outros sintomas foram bem mais discretos que em P. maximum. A ocorrência de compostos fenólicos foi registrada pela coloração com fucsina em todas as regiões da lâmina onde foram observadas lesões. Ao microscópio eletrônico de varredura foi observado o achatamento e formação de concavidades nas paredes externas das células. Este experimento confirma a maior sensibilidade de P. maximum ao flúor e revela algumas características anatômicas de C. gayana que, entre outros fatores, podem estar contribuindo para a maior resistência desta espécie a este poluente.

  19. Macronutrients leaf contents of corn in consortium with forage of the genus Panicum and Urochloa

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    Verena Micheletti Protes

    2013-12-01

    Full Text Available In recent years, the corn crop in Brazil has undergone major technological changes, aiming at a sustainable production. This improvement may be related to appropriate management, which includes, among other practices, crop rotation and tillage; that one can get through crop-livestock integration (CLI. The CLI can be done by the consortium sequence or crop rotation with annual forages in order to recover degraded pastures. This work aimed to evaluate the macronutrient leaf content of corn intercropped with forages of the genus Panicum and Urochloa. The experiment was conducted at the Farm for Teaching, Research and Extension, Faculty of Engineering - UNESP, Ilha Solteira in an Oxisol in Savannah conditions, being in no-tillage for 8 years (previous corn crop. In nitrogen fertilization was applying 100 kg ha-1 of N as urea. The experimental design was a randomized block with four replications and five treatments: Panicum maximum cv. Tanzania sown during the nitrogen fertilization (CTD of the corn; Panicum maximum cv. Mombaça sown during the nitrogen fertilization (CMD of the corn; Urochloa brizantha Xaraes sown during the occasion of nitrogen fertilization (CBD of the corn; Urochloa ruziziensis sown during the nitrogen fertilization (CRD of the corn, and corn without intercropping (CWI. The grasses seeds were mixed with fertilizer minutes before sowing and placed in fertilizer seeder compartment and the fertilizer were deposited in the soil at a depth of 0.03 m in the amount of 5 kg ha-1. It was observed that there was no significant difference between the single corn tillage and the corn in intercropping with different modalities of forages of genus Panicum and Urochloa to foliar contents of N, P, K, Ca and Mg, demonstrating that the consortium did not influence the absorption of nutrients by corn. In respect to S, the consortium CTD, was higher only when compared at CWI, however, did not differ significantly from the others (Table 1. The

  20. Compactação do solo e macronutrientes primários na Brachiaria brizantha cv. Piatã e Panicum maximum cv. Mombaça Soil compaction and primary macronutrients in Brachiaria brizantha cv. Piatã e Panicum maximum cv. Mombaça

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    Carlos E. A. Cabral

    2012-04-01

    Full Text Available Os macronutrientes primários possuem papel relevante na adubação de forrageiras, em função da sua participação no custo de produção, razão pela qual se objetivou avaliar os efeitos da compactação na concentração de macronutrientes primários em folhas diagnósticas dos capins Piatã e Mombaça. O experimento foi realizado em casa de vegetação, com delineamento inteiramente casualizado, composto de oito tratamentos e três repetições, em esquema fatorial 2x4, com duas gramíneas (capim-piatã e capim-mombaça e de quatro densidades do solo (1,0; 1,2; 1,4 e 1,6 Mg m-3. Dois cortes foram realizados, o primeiro aos 42 dias após o desbaste e o segundo 46 dias após o primeiro corte. No primeiro período de crescimento das gramíneas forrageiras a compactação do solo interfere na absorção de nitrogênio e fósforo enquanto no segundo período de crescimento ocorre limitação na absorção de nitrogênio e potássio. O nitrogênio é o macronutriente primário mais limitado pela compactação do solo.The primary macronutrients have an important role in the forage fertilization, depending on their contribution to the production cost. This paper aimed to evaluate the effects of soil compaction on the concentration of primary macronutrients present in diagnostic leaves of Piatã and Mombaça grasses. The experiment was conducted in a greenhouse with a randomized statistical design, consisting of eight treatments and three replications in 2 x 4, factorial scheme, with two grases (Piatã grass and Mombaça and four soil densities (1.0, 1.2 , 1.4 and 1.6 Mg m-3. Two harvest of shoots were made, the first 42 days after the plant thinning, and the second 46 days after the first cutting. In the first growing period, the soil compaction interfere with the absorption of nitrogen and phosphorus, while in the second growing period there is a limitation in the absorption of nitrogen and potassium. Nitrogen is the primary macronutrient most

  1. PRODUÇÃO DE MASSA SECA, NÚMERO DE PERFÍLIOS E ÁREA FOLIAR DO CAPIM MOMBAÇA CULTIVADO EM DIFERENTES NÍVEIS DE NITROGÊNIO E FÓSFORO GROUWTH OF Panicum maximum Jacq. Cv. MOMBAÇA UNDER DIFFERENT LEVELS OF NITROGEN AND PHOSPHOROUS IN A GREEN HOUSE

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    Beneval Rosa

    2008-10-01

    Full Text Available

    No presente trabalho avaliaram-se diferentes combinações de doses de nitrogênio e de fósforo na produção de massa seca foliar, número de perfilhos e expansão da área foliar de Panicum maximum Jacq. cv. Mombaça. Para tanto, desenvolveu-se um experimento em casa de vegetação na Escola de Agronomia e Engenharia de Alimentos da Universidade Federal de Goiás. Fez-se uso, como substrato de crescimento, de 7,0 dm3 de terra, acondicionado em vaso plástico de 9,0 dm3 proveniente de um Latossolo Vermelho-escuro distrófico coletado na Fazenda Samambaia no município de Goiânia, GO. Os tratamentos se constituíram da aplicação de quatro doses de nitrogênio na forma de uréia (0, 100, 200 e 400 mg/dm3 de N e quatro doses de fósforo na forma de superfosfato triplo (0, 250, 500 e 750 mg/dm3 de P em quatro repetições. Parcelaram-se as doses de nitrogênio em três aplicações com intervalos de dez dias para cada corte de avaliação. O delineamento experimental foi o inteiramente casualizado com os tratamentos arranjados em um fatorial completo 24 , sendo os fatores as doses de nitrogênio e fósforo. Aos 60 dias após a emergência, efetuou-se um corte de uniformização a 20 cm de altura do solo. Para fins de avaliações, realizaram-se mais três cortes (20 cm de altura a cada trinta dias. Concluiu-se que doses de nitrogênio entre 300 e 400 mg/dm3 de N combinadas com doses de fósforo entre 250 e 500 mg/dm3 de P são as mais indicadas para trabalhos em casa de vegetação com o capim-Mombaça.

    PALAVRAS-CHAVES: Área foliar, capim-Mombaça, massa seca foliar, perfilhos, planta C4.

    The aim of this study was to evaluate the effects of different combinations of nitrogen and phosphorous levels on leaf area, leaf dry matter and tillers number of Panicum maximum Jacq. Cv

  2. Performance of Nellore steers grazing on Panicum maximum Jacq cv. Mombaça receiving chopped sugar cane tops and protein supplementation =Desempenho de novilhos Nelore em pastagem de Panicum maximum Jacq. cv. Mombaça recebendo cana-de-açúcar picada e suplementação proteica

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    Silvana Teixeira

    2010-10-01

    Full Text Available The aim of this study was to evaluate protein supplementation on theperformance of steers grazing on Mombaça grass and receiving chopped sugar cane tops at a level of 0.80% of live weight (dry matter (DM basis, during the dry season. Forage availability and quality of the experimental pasture were also evaluated. Thirty-two Nellore steers, weighing 300 kg (. 25.80 of initial live weight, eight per treatment, were used. The statistical design was completely randomized and each steer group was allocated to one of four paddocks (1.125 ha paddock-1. All steers received a protein supplement at 0.40% of live weight (DM basis and the four treatments consisted of the following four crude protein (CP concentrations in supplements: 12.5, 25.0, 37.5 and 50.0% CP (DM basis. Average forage mass availability and green leaf blades availability were 10,069 and 2,195 kg of DM ha-1, respectively. Average CP, neutral fiber detergent (NDF and in vitro dry matter digestibility (IVDMD in forage mass were 6.87, 62.63 and 49.80%, respectively. Average daily gain was 0.61 kg steer-1 day-1 and these results show that the strategy of feeding steers in pasture, with chopped sugar cane tops (0.80% LW and protein supplement with 12.50% CP (0.40% LW, during the dry season, allows high gain per area (363 kg live weight ha-1.No experimento foi avaliado o efeito da suplementação proteica sobre o desempenho de novilhos que pastejam capim Mombaça e recebem cana-de-açúcar picada, em nível de 0,80% do peso vivo (PV (base matéria seca, MS. Também foram avaliadas a disponibilidade e a qualidade da forragem da área experimental. Foram usados 32 novilhos da raça Nelore, com peso inicial de 300 kg (± 25,80. O delineamento experimental foi inteiramente casualizado e cada grupo de novilhos foi alocado para cada um dos quatro piquetes (1,125 ha piquete-1. Os animais receberam suplemento proteico em nível de 0,40% do PV (base MS e os quatro tratamentos consistiam de suplementos

  3. Potential for nitrogen fixation and biomass production in Panicum ...

    African Journals Online (AJOL)

    Azospirillum sp. contributed approximately 48 per cent of total aerobic counts and was found to be capabl e of growth under strictly anaerobic conditions where it constituted about 11 per cent of total counts. Panicum maximum was found to be capable of growth in soils of clay-loam, sandyclay or purely loam types with pH ...

  4. Evaluation of forage grass resistance to Mahanarva fimbriolata (Stål

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    Eliane Grisoto

    2017-12-01

    Full Text Available ABSTRACT The aim of this study was to select forage grasses with potential resistance to Mahanarva fimbriolata by assessing effects on insect. No-choice assays were conducted with 12 genotypes and laboratory-reared insects. The following parameters were assessed: mortality and duration of the nymphal stage; adult weight and longevity; pre-oviposition period; number of eggs/female; viability and duration of the embryonic period. As main result it was verified that the mortality of nymphs reared on Panicum maximum cv. Paredão is almost complete and that this forage grass may be characterized as resistant to this insect by antibiosis. Further, the grasses can be divided into three groups following a cluster analysis: P. maximum cv. Aries, Setaria sphacelata cv. Kazungula, Brachiaria humidicola, A. gayanus and P. maximum cv. Aruana, which are insect-resistant grasses; Brachiaria decumbens cv. Basilisk, B. dictyoneura, B. brizantha cv. MG-4 and B. ruziziensis, which are moderately resistant grasses; and B. brizantha MG-5 and B. brizantha ecotype BB185, which are susceptible grasses.

  5. Ensilage characteristics of three tropical grasses as influenced by stage of growth and addition of molasses.

    Science.gov (United States)

    Tjandraatmadja, M; Norton, B W; Mac Rae, I C

    1994-01-01

    When molasses was added during ensilage of three tropical grasses [hamil grass (Panicum maximum cv. Hamil), pangola grass (Digitaria decumbens) and setaria (Setaria sphacelata cv. Kazungula)] the final pH, concentration of fermentation acids (except lactic acid) and NH3-N content were all similar after 100 days of incubation. Pangola grass silage had significantly higher lactic acid content (66 g/kg dry matter) than the other two. Adding either 4 or 8% (w/w) molasses reduced NH3-N, volatile fatty acid content and pH but increased lactic acid content in the final silages. Numbers of lactic acid bacteria remained approximately constant during the course of the fermentation, although large differences were noted in the species composition of the populations. At the time of ensiling, only Pediococcus spp. and Leuconostoc spp. were detected. By 5 days, the homo-fermentative population, notably Lactobacillus plantarum, dominated (43%) and remained dominant. Hetero-fermentative rods were only detected in the 100-day silage, where they represented 29% of the strains isolated. Homo-fermenters were more abundant in pangola (60%) and setaria (47%) silages than hamil (27%) silages. Homo-fermenter populations were lowest in the 12-week forage. Molasses additions increased homo-fermenter populations. Pangola grass gave the best quality silage but, since the water-soluble carbohydrate content in the grasses was insufficient to promote a strong lactic fermentation, the addition of 20 to 30 kg molasses/tonne should achieve satisfactory preservation.

  6. Inoculation and inter-cropping of legumes in established grass for increasing biomass of fodder

    International Nuclear Information System (INIS)

    Ullah, M.A.; Hussain, N.

    2014-01-01

    Livestock sector has become very important component of agriculture sector in the world due to variety of dairy and meat products and high income to the farmers. In Pakistan, this vast resource faces many crucial challenges like low quality and high priced feed and fodder and limited chances of increasing area under fodders due to competition for food crops. Intercropping (33%, 50% and 67%) of Panicum maximum grass and legumes (Vicia sativa and cowpeas) coupled with inoculation was studied under rainfed conditions at National Agricultural Research Centre (NARC) Islamabad, Pakistan. Intercropping significantly increased tillering of grass. Seed inoculation of legumes also gave maximum tillers. The grass and legumes biomass without any treatment were recorded as 7.09 and -18.17 t ha, respectively, during two years of study. Mixed fodder -1 production increased to 11.62, 13.6 and 14.13 t ha with 33%, 50% and 67% intercropping, respectively. Respective values of biomass were -1 observed as 13.18, 13.70 and 17.87 t ha when combined with inoculation. Intercropping of grass and legumes 67% with inoculation was assessed as the best treatment. The increases were computed as 304%, 230%, 132%, and 60% over grass alone in the first, second, third and fourth crops while respective increases were 101%, 151%, 165% and 74% over monoculture legumes. (author)

  7. Five nuclear loci resolve the polyploid history of switchgrass (Panicum virgatum L.) and relatives.

    Science.gov (United States)

    Triplett, Jimmy K; Wang, Yunjing; Zhong, Jinshun; Kellogg, Elizabeth A

    2012-01-01

    Polyploidy poses challenges for phylogenetic reconstruction because of the need to identify and distinguish between homoeologous loci. This can be addressed by use of low copy nuclear markers. Panicum s.s. is a genus of about 100 species in the grass tribe Paniceae, subfamily Panicoideae, and is divided into five sections. Many of the species are known to be polyploids. The most well-known of the Panicum polyploids are switchgrass (Panicum virgatum) and common or Proso millet (P. miliaceum). Switchgrass is in section Virgata, along with P. tricholaenoides, P. amarum, and P. amarulum, whereas P. miliaceum is in sect. Panicum. We have generated sequence data from five low copy nuclear loci and two chloroplast loci and have clarified the origin of P. virgatum. We find that all members of sects. Virgata and Urvilleana are the result of diversification after a single allopolyploidy event. The closest diploid relatives of switchgrass are in sect. Rudgeana, native to Central and South America. Within sections Virgata and Urvilleana, P. tricholaenoides is sister to the remaining species. Panicum racemosum and P. urvilleanum form a clade, which may be sister to P. chloroleucum. Panicum amarum, P. amarulum, and the lowland and upland ecotypes of P. virgatum together form a clade, within which relationships are complex. Hexaploid and octoploid plants are likely allopolyploids, with P. amarum and P. amarulum sharing genomes with P. virgatum. Octoploid P. virgatum plants are formed via hybridization between disparate tetraploids. We show that polyploidy precedes diversification in a complex set of polyploids; our data thus suggest that polyploidy could provide the raw material for diversification. In addition, we show two rounds of allopolyploidization in the ancestry of switchgrass, and identify additional species that may be part of its broader gene pool. This may be relevant for development of the crop for biofuels.

  8. Five nuclear loci resolve the polyploid history of switchgrass (Panicum virgatum L. and relatives.

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    Jimmy K Triplett

    Full Text Available Polyploidy poses challenges for phylogenetic reconstruction because of the need to identify and distinguish between homoeologous loci. This can be addressed by use of low copy nuclear markers. Panicum s.s. is a genus of about 100 species in the grass tribe Paniceae, subfamily Panicoideae, and is divided into five sections. Many of the species are known to be polyploids. The most well-known of the Panicum polyploids are switchgrass (Panicum virgatum and common or Proso millet (P. miliaceum. Switchgrass is in section Virgata, along with P. tricholaenoides, P. amarum, and P. amarulum, whereas P. miliaceum is in sect. Panicum. We have generated sequence data from five low copy nuclear loci and two chloroplast loci and have clarified the origin of P. virgatum. We find that all members of sects. Virgata and Urvilleana are the result of diversification after a single allopolyploidy event. The closest diploid relatives of switchgrass are in sect. Rudgeana, native to Central and South America. Within sections Virgata and Urvilleana, P. tricholaenoides is sister to the remaining species. Panicum racemosum and P. urvilleanum form a clade, which may be sister to P. chloroleucum. Panicum amarum, P. amarulum, and the lowland and upland ecotypes of P. virgatum together form a clade, within which relationships are complex. Hexaploid and octoploid plants are likely allopolyploids, with P. amarum and P. amarulum sharing genomes with P. virgatum. Octoploid P. virgatum plants are formed via hybridization between disparate tetraploids. We show that polyploidy precedes diversification in a complex set of polyploids; our data thus suggest that polyploidy could provide the raw material for diversification. In addition, we show two rounds of allopolyploidization in the ancestry of switchgrass, and identify additional species that may be part of its broader gene pool. This may be relevant for development of the crop for biofuels.

  9. Genetic-Phenotypic Variability and Correlation between Morphology-Anatomy-Physiology Characteristics and Dry Matter Yield of Polyploidized Forage Grasses under Aluminum Stressed Condition

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    S Anwar

    2007-01-01

    Full Text Available The study was conducted with the aim to know the genetic-phenotypic variability (heritability value, and correlation between morphology-anatomy-physiology characters and dry matter yield (DMY of polyploidized forage grasses under aluminum (Al stressed condition. A total of 16 forage grass genotypes (polyploid and diploid Brachiaria brizantha, Brachiaria decumbens, Setaria sphacelata, Setaria splendida, Panicum muticum, Panicum maximum, Pennisetum purpureum, and Pennisetum purpupoides were subjected to Al-stressed (16 mM Al2(SO43. The treatments were allotted to a Randomized Completely Block Design with monofactorial pattern (genotypes and 5 blocks in each treatment. The morphology-anatomy-physiology characteristics evaluated were plant height, leaf number, tiller number, leaf color, chlorophyll content, stomata number, chloroplast number, leaf nitrate reductase activity, dry matter, wet matter yield, dry matter yield, stress tolerance index and pH media. Results showed the polyploidization increased stress tolerance index of grasses. The genetic-phenotypic variability (heritability value estimates for all morphology-anatomy-physiology characteristics were high. Most morphology-anatomy-physiology characteristics, except leaf number, chlorophyll content and chloroplast number, had significant correlation to dry matter yield. In conclusion, evaluation on selection progress of dry matter yield of forage grasses can be effectively done by selection for yield of wet matter, plant height, leaf color, branch number, stomata number, leaf nitrate reductase activity, pH media, and dry matter simultaneously. (Animal Production 9(1: 23-29 (2007

  10. Some Aspects Of The Autecology Of Panicum Turgidum Forsk

    OpenAIRE

    Ismail, A. M. A. [احمد محمد علي اسماعيل; El Seed, M. T.

    1983-01-01

    The germination of Panicum turgidum seeds was tested under different conditions. They showed ability to germinate under a range of temperatures from 25-42°C. The maximum percentage of germination was 45%, at 30°C. The species responded differently to the various chemical substances used to stimulate its germination. The particular effect of each chemical substance was discussed. The percentage of seedling emergence was highest in the case of seeds sown at 0. cm depth and decreased gradually a...

  11. Rehabilitation with forage grasses of an area degraded by urban solid waste deposits

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    Vanessa Soares Miranda

    2012-01-01

    Full Text Available Dry matter yield and chemical composition of forage grasses harvested from an area degraded by urban solid waste deposits were evaluated. A split-plot scheme in a randomized block design with four replicates was used, with five grasses in the plots and three harvests in the subplots. The mineral content and extraction and heavy metal concentration were evaluated in the second cut, using a randomized block design with five grasses and four replicates. The grasses were Brachiaria decumbens cv. Basilisk, Brachiaria ruziziensis, Brachiaria brizantha cv. Marandu and cv. Xaraés, and Panicum maximum cv. Tanzânia, cut at 42 days of regrowth. The dry matter yield per cut reached 1,480 kg ha-1; the minimum crude protein content was 9.5% and the average neutral detergent fiber content was 62.3%. The dry matter yield of grasses was satisfactory, and may be an alternative for rehabilitating areas degraded by solid waste deposits. The concentration of heavy metals in the plants was below toxicity levels; the chemical composition was appropriate, except for phosphorus. The rehabilitated areas may therefore be used for grazing.

  12. Production of tropical forage grasses under different shading levels

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    Francisco Eduardo Torres

    2017-12-01

    Full Text Available This study aimed to evaluate the forage production of three tropical forage grasses under different shading levels. The experiment was conducted in a greenhouse at Universidade Estadual de Mato Grosso do Sul, University Unit of Aquidauana (UEMS/UUA, in a soil classified as Ultisol sandy loam texture. The treatments consisted of three grasses species combinations (B. brizantha cv. Marandu, B. decumbens cv. Basilisck and Panicum maximum cv. Tanzania, submitted to four shading levels (0, 30, 50 and 75%, arranged in a completely randomized blocks design in a factorial 3 x 4, with eight replications. After harvest, the plants were separated into shoot and roots for determination of shoot fresh mass (SFM, shoot dry mass (SDM and roots dry mass production. After analysis of variance, the qualitative factor was subjected to comparison of averages by Tukey’s test, and the quantitative factor to analysis of polynomial regression, being interactions appropriately unfolded. It was verified that B. decumbens, by its linearly increasing production of forage and less decrease of root formation, is the most recommended for shading conditions compared to grasses Tanzania and Marandu.

  13. Eficiência biológica e econômica de pasto de capim-tanzânia adubado com nitrogênio no final do verão Biological and economic efficiency of Panicum maximum fertilized with nitrogen in the end of summer

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    Valéria Pacheco Batista Euclides

    2007-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o ganho de peso vivo, a capacidade de suporte e a eficiência bioeconômica em pastos de Panicum maximum, cultivar Tanzânia, com aplicação de uma segunda dose de adubação nitrogenada no final do verão. Anualmente foram aplicados em cobertura: 50, 17,48, e 33,2 kg ha-1 de N, P e K, respectivamente, em novembro. A metade da área recebeu 50 kg ha-1 de N adicional em março. Os tratamentos foram pastos de capim-tanzânia com 50 e 100 kg ha-1 de N. Os piquetes foram submetidos ao pastejo rotacionado. Foram utilizados quatro animais por piquete, e animais adicionais foram colocados e removidos para manter resíduos semelhantes pós-pastejo. Não houve efeito da adubação nitrogenada sobre o ganho médio diário. No entanto, o pasto adubado com 100 kg ha-1 de N (1,8 UA ha-1 resultou em maior capacidade de suporte e maior produtividade (780 kg ha-1 por ano de PV do que o adubado com 50 kg ha-1 de N (1,5 UA ha-1 e com 690 kg ha-1 por ano de PV, em média. A eficiência da conversão do N em produto animal foi de 1,8 kg de PV por hectare para cada quilograma adicional de N aplicado. O uso da adubação nitrogenada no final do verão é uma alternativa bioeconomicamente viável para a produção sustentável de carne.The objective of the work was to estimate animal live weight gain, the pasture carrying capacity, and the bioeconomic efficiency of Panicum maximum, cultivar Tanzânia pastures, with a second application of nitrogen fertilizer in the end of summer (March. Maintenance fertilizer was 50, 17.5 and 33.2 kg ha-1 of N, P and K, respectively, applied annually in November. Besides, in half of the area, an additional 50 kg ha-1 of N was applied in March. Treatments were tanzânia pastures with two levels of nitrogen fertilization, 50 and 100 kg ha-1. The paddocks were submitted to a rotational grazing. Four steers were kept in each paddock, and additional steers were allocated and removed to assure similar

  14. Avaliação de três cultivares de Panicum maximum Jacq. sob pastejo: disponibilidade de forragem, altura do resíduo pós-pastejo e participação de folhas, colmos e material morto

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    Brâncio Patrícia Amarante

    2003-01-01

    Full Text Available Três cultivares de Panicum maximum Jacq. submetidos a pastejo rotativo foram avaliados ao longo do ano, antes e após o período de pastejo, quanto às disponibilidades de matéria seca total e de folhas, altura, profundidade pastejada, densidade, participações de folhas, colmos e material morto, relações folha/colmo e folha/material morto. Os tratamentos constituíram em: 1 cv. Tanzânia + 50 kg/ha de N, 2 cv. Tanzânia + 100 kg/ha de N, 3 cv. Mombaça + 50 kg/ha de B e 4 cv. Massai + N 50 kg/ha de N. O cultivar Mombaça apresentou menores disponibilidades de folhas, e maiores proporções de colmo, enquanto o cv. Massai tanto apresentou características que poderiam favorecer a seleção de folhas, como maior densidade de MS e maior relação folha/colmo, como a característica desfavorável de apresentar menor relação folha/material morto. No cv. Tanzânia, a adubação nitrogenada no final do período chuvoso trouxe benefícios apenas em março, quando houve aumento nas relações folha/colmo e folha/material morto. A profundidade pastejada correlacionou-se positivamente com a altura, e os animais pastejaram em média 41% da altura da pastagem, no período seco, e 47% no período chuvoso.

  15. Acúmulo de forragem e eficiência de utilização do Nitrogênio em pastagens de Panicum maximum Jacq. (Acesso BRA-006998 adubadas com Nitrogênio - DOI: 10.4025/actascianimsci.v25i2.2072 Forrage increment and efficiency of nitrogen in pastures with Panicum maximum Jacq. (BRA-006998 manured with nitrogen - DOI: 10.4025/actascianimsci.v25i2.2072

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    Euclides Braga Malheiros

    2003-04-01

    Full Text Available O presente trabalho foi conduzido no Iapar-Paranavaí, Estado do Paraná e objetivou avaliar o efeito da adubação nitrogenada no acesso BRA-006998, durante o período de 15/10/1998 a 03/05/1999. 4 doses de nitrogênio (0, 150, 300 e 450kg/ha/ano foram aplicadas na pastagem com lotação rotacionada, utilizando o delineamento em blocos ao acaso, em esquema de parcelas subdivididas (doses de nitrogênio - parcelas e ciclos de pastejo - subparcela. A taxa de acúmulo de matéria seca máxima foi de 73,9kg; 96,2kg; 150,3kg; 189,6kg e 129,9kg/ha/dia (424kg, 438kg, 397kg, 385kg e 414kg de nitrogênio/ha/ano, respectivamente nos ciclos de pastejo 1, 2, 3, 4 e 5, respectivamente. A eficiência de utilização do nitrogênio na produção de matéria seca não diferiu entre os tratamentos 150kg e 300kg de nitrogênio/ha/ano, sendo a eficiência obtida com 150kg de nitrogênio/ha/ano maior do que a obtida com 450kg de nitrogênio/ha.The work was carried out at Iapar in Paranavaí, state of Paraná, to evaluate the effect of nitrogen fertilization on access of BRA-006998, from 10/15/1998 to 05/03/1999. Four doses of N (0; 150; 300; and 450kg/ha/year were applied to the pastures managed according to a rotational grazing. A randomized block design was used with split-plots, with N-doses studied in the plots and the GCs in the split-plots. The DM accumulation rate presented maximum value of 73.9; 96.2; 150.3; 189.6; and 129.9kg/ha/day (424; 438; 397; 385; 414kg N/ha/year, respectively in the GCs 1, 2, 3, 4 and 5, respectively. The efficiency of N utilization in DM production did not differ between the treatments of 150 and 300kg N/ha/year, where the efficiency obtained with 150kg N/ha/year is higher than that obtained with 450kg N/ha/year.

  16. Ranking of grass species according to visible wilting order and rate ...

    African Journals Online (AJOL)

    The leaf water potential and soil water content at which each grass species wilted were recorded. Keywords: availability; digitaria argyrograpta; digitaria eriantha; grasses; leaf water potential; moisture stress; neutron probe; orange free state; panicum stapfianum; soil water; soil water content; soil water potential; south africa ...

  17. Karyotype studies in Panicum maximum Jacq. | Adedeji | Nigerian ...

    African Journals Online (AJOL)

    No Abstract. Nigerian Journal of Genetics Vol. 18 2003: pp. 5-10. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/njg.v18i1.42284 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More ...

  18. An evaluation of Panicum maximum cv. Gatton: 3. The partial ...

    African Journals Online (AJOL)

    Unknown

    quantify the partial digestion of organic matter (OM), nitrogen (N) and neutral detergent fibre (NDF) in sheep .... number of publications have indicated that stage of maturity, as well as level of intake, could have an effect on digestion in the .... large proportion of N in mature pasture is associated with cell walls. This may ...

  19. NUTRITIVE QUALITY OF TEN GRASSES DURING THE RAINY SEASON IN A HOT-HUMID CLIMATE AND ULTISOL SOIL

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    Rodrigo Ortega-Gómez

    2011-11-01

    Full Text Available The nutritive quality of ten grasses harvested at 3, 6, 9 and 12 weeks of regrowth was assessed during the rainy season (August-October 2008, in the humid tropics of Veracruz, Mexico. Grasses tested included four Brachiaria spp.: “insurgente”–B. brizantha, “signal”–B. decumbens, Chetumal–B. humidicola, “mulato I”–B. brizantha x B. ruziziensis; three Panicum maximum: Mombasa, “privilegio”, Tanzania; and three Pennisetum spp.: Taiwán, and the hybrids P. purpureum x P. glaucum “Cuban” king grass and “purple” king grass. Means for crude protein by grass group were: Pennisetum spp. (9.9 % = P. maximum (8.7 % > Brachiaria spp. (7.6 %, whereas means for in situ dry matter disappearance (ISD were: Pennisetum spp. (69.7 % > Brachiaria spp. (65.1 % > P. maximum (59.7 %. Crude protein and ISD significantly decreased by 0.42 % and 1.50 % per week. Neutral detergent fiber was not affected by model effects (mean 71.4 %. Means for acid detergent fiber (ADF by grass group were: P. maximum (47.6 % = Pennisetum spp. (44.0 % > Brachiaria spp. (42.8 %, whereas means for lignin (LIG were: P. maximum (8.5 % > Pennisetum spp. (7.6 % > Brachiaria spp. (6.7 %. The ADF and LIG significantly increased by 1.21 % and 0.19 % per week. Pennisetum spp. had the highest nutritive value at all regrowth ages.

  20. Assessment of some macromineral concentration of a grass/ legume ...

    African Journals Online (AJOL)

    The assessment of macromineral concentration of Panicum/Stylosanthes mixtures was carried out at the Cattle Production Venture, Federal University of Agriculture, Abeokuta, in Southwest Nigeria. The study aimed to determine the concentration of some macromineral elements in the grass/legume pasture grazed by the ...

  1. On the seed production of tropical grasses in Kenya

    NARCIS (Netherlands)

    Boonman, J.G.

    1973-01-01

    The small amount of viable seed that can be harvested from tropical ley grasses such as Chloris gayana, Setaria sphacelata and Panicum spp. is largely due to the wide range in maturity between different heads and in maturity between seeds in any head. Ripe seed is also liable

  2. Effects of processing phases on the quality of massai grass seeds

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    Lilian Faria de Melo

    Full Text Available ABSTRACT Massai grass is an important tropical forage grass. The harvested seeds upon being received by the company, are found to be contaminated with impurities which are removable by processing machines. This procedure is necessary to produce seeds of a quality level within standards established for commercialization and sowing purposes. The objective of this project was to evaluate the effects of processing phases on the physical and physiological quality of massai grass (Panicum maximum x P. infestum, cv. Massai seeds for commercialization purposes. Seeds were sampled before processing and after leaving the air and screen machine (upper and intermediary screens and bottom; first gravity table (drift, upper and intermediate spouts; treating machine; and second gravity table (upper, intermediate, and lower spouts. Seeds were evaluated as to water content, physical (purity and 1,000 seeds weight and physiological quality (germination, first count of germination, seedling vigor classification, accelerated aging, seedling emergence in the field, speed of emergence index, and primary root length, shoot length. Massai grass seeds had their physical and physiological qualities improved when they were processed by an air and screen machine and a gravity table. Seeds from the intermediate discharge spout of the first gravity table, after going through the air and screen machine, are those of with highest physiological potential. The seeds of this species do not need to be processed to fit the germination and purity standards when the national market is the goal.

  3. Production and nutrition of irrigated Tanzania guinea grass in response to nitrogen fertilization

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    Maria Celuta Machado Viana

    2014-05-01

    Full Text Available The objective of this study was to evaluate the effects of nitrogen (N fertilization in the four seasons of the year on forage production, nitrate (NO3 in the sap, total N in the forage and relative chlorophyll index (SPAD reading in the leaves of irrigated Panicum maximum cv. Tanzania grass, establishing their critical ranges. In addition, we evaluated the ability to predict forage production based on NO3 in the sap, total N in the forage and relative chlorophyll index. The soil in the experimental area was classified as an Oxisol (Red-Yellow Latosol with a clayey texture. Annual rates of N (0, 200, 400 and 800 kg ha-1 in the form of urea were the treatments tested. Irrigation was performed through a conventional spray system. The NO3 content in the sap and the relative chlorophyll index were measured in leaves using a portable meter with NO3 selective electrode and the SPAD-502 portable chlorophyll meter device, respectively. Tanzania guinea grass was very responsive to N fertilization, except in the winter. The critical ranges of the SPAD reading proved to be more adequate for monitoring the nutritional state of N of Tanzania guinea grass in the different seasons of the year than the NO3content in the sap and the total N content in the dry matter. Use of the chlorophyll meter is more advantageous than the use of the portable meter with an nitrate selective electrode for predicting the nutritional status of Tanzania guinea grass.

  4. An African grassland responds similarly to long-term fertilization to the Park Grass experiment.

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    David Ward

    Full Text Available We compared the results of a long-term (65 years experiment in a South African grassland with the world's longest-running ecological experiment, the Park Grass study at Rothamsted, U.K. The climate is warm and humid in South Africa and cool and temperate in England. The African grassland has been fertilized with two forms of nitrogen applied at four levels, phosphorus and lime in a crossed design in 96 plots. In 1951, about 84% of plant cover consisted of Themeda triandra, Tristachya leucothrix and Setaria nigrirostris. Currently, the dominant species are Panicum maximum, Setaria sphacelata and Eragrostis curvula, making up 71% of total biomass. As in the Park Grass experiment, we found a significant (additive interaction effect on ANPP of nitrogen and phosphorus, and a (marginally significant negative correlation between ANPP and species richness. Unlike the Park Grass experiment, there was no correlation between ANPP and species richness when pH was included as a covariate. There was also a significant negative effect of nitrogen amount and nitrogen form and a positive effect of lime on species richness and species diversity. Soil pH had an important effect on species richness. Liming was insufficient to balance the negative effects on species richness of nitrogen fertilization. There was a significant effect of pH on biomass of three abundant species. There were also significant effects of light on the biomass of four species, with only Panicum maximum having a negative response to light. In all of the abundant species, adding total species richness and ANPP to the model increased the amount of variance explained. The biomass of Eragrostis curvula and P. maximum were negatively correlated with species richness while three other abundant species increased with species richness, suggesting that competition and facilitation were active. Consistent with the results from the Park Grass and other long-term fertilization experiments of grasslands

  5. An African grassland responds similarly to long-term fertilization to the Park Grass experiment.

    Science.gov (United States)

    Ward, David; Kirkman, Kevin; Tsvuura, Zivanai

    2017-01-01

    We compared the results of a long-term (65 years) experiment in a South African grassland with the world's longest-running ecological experiment, the Park Grass study at Rothamsted, U.K. The climate is warm and humid in South Africa and cool and temperate in England. The African grassland has been fertilized with two forms of nitrogen applied at four levels, phosphorus and lime in a crossed design in 96 plots. In 1951, about 84% of plant cover consisted of Themeda triandra, Tristachya leucothrix and Setaria nigrirostris. Currently, the dominant species are Panicum maximum, Setaria sphacelata and Eragrostis curvula, making up 71% of total biomass. As in the Park Grass experiment, we found a significant (additive) interaction effect on ANPP of nitrogen and phosphorus, and a (marginally significant) negative correlation between ANPP and species richness. Unlike the Park Grass experiment, there was no correlation between ANPP and species richness when pH was included as a covariate. There was also a significant negative effect of nitrogen amount and nitrogen form and a positive effect of lime on species richness and species diversity. Soil pH had an important effect on species richness. Liming was insufficient to balance the negative effects on species richness of nitrogen fertilization. There was a significant effect of pH on biomass of three abundant species. There were also significant effects of light on the biomass of four species, with only Panicum maximum having a negative response to light. In all of the abundant species, adding total species richness and ANPP to the model increased the amount of variance explained. The biomass of Eragrostis curvula and P. maximum were negatively correlated with species richness while three other abundant species increased with species richness, suggesting that competition and facilitation were active. Consistent with the results from the Park Grass and other long-term fertilization experiments of grasslands, we found a

  6. Impacts of managing perennial grasses in the northern Midwest United States for bioenergy on soil organic C and nitrous oxide emission

    Science.gov (United States)

    In the USA perennial grasses [e.g., switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerdardii Vitman)] are proposed as cellulosic feedstock. Perennial grasses are often touted as being low input and as having a C-neutral foot print, but managing them as bioenergy feedstock means addin...

  7. Complete nucleotide sequences and virion particle association of two satellite RNAs of panicum mosaic virus.

    Science.gov (United States)

    Pyle, Jesse D; Monis, Judit; Scholthof, Karen-Beth

    2017-08-15

    Over six decades ago, panicum mosaic virus (PMV) was identified as the first viral pathogen of cultivated switchgrass (Panicum virgatum). Subsequently, PMV was demonstrated to support the replication of both a satellite RNA virus (SPMV) and satellite RNA (satRNA) agents during natural infections of host grasses. In this study, we report the isolation and full-length sequences of two PMV satRNAs identified in 1988 from St. Augustinegrass (Stenotaphrum secundatum) and centipedegrass (Eremochloa ophiuroides) hosts. Each of these satellites have sequence relatedness at their 5'- and 3'-ends. In addition, satC has a region of ∼100 nt complementary to the 3'-end of the PMV genome. These agents are associated with purified virions of SPMV infections. Additionally, satS and satC RNAs contain conserved in-frame open reading frames in the complementary-sense sequences that could potentially generate 6.6- and 7.9-kDa proteins, respectively. In protoplasts and plants satS is infectious, when co-inoculated with the PMV RNA alone or PMV+SPMV RNAs, and negatively affects their accumulation. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Prospects for Hybrid Breeding in Bioenergy Grasses

    DEFF Research Database (Denmark)

    Aguirre, Andrea Arias; Studer, Bruno; Frei, Ursula

    2012-01-01

    , we address crucial topics to implement hybrid breeding, such as the availability and development of heterotic groups, as well as biological mechanisms for hybridization control such as self-incompatibility (SI) and male sterility (MS). Finally, we present potential hybrid breeding schemes based on SI...... of different hybrid breeding schemes to optimally exploit heterosis for biomass yield in perennial ryegrass (Lolium perenne L.) and switchgrass (Panicum virgatum), two perennial model grass species for bioenergy production. Starting with a careful evaluation of current population and synthetic breeding methods...

  9. Characterization of tropical forage grass development pattern through the morphogenetic and structural characteristics Caracterização do padrão de desenvolvimento de gramíneas forrageiras tropicais por meio das características morfogênicas e estruturais

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    Carlindo Santos Rodrigues

    2011-03-01

    Full Text Available An experiment was carried out with the objective to evaluate growth pattern of tropical forage grass under free growth by using morphogenetic and structural characteristics with the expectation of using this study for forage grass evaluation protocol. The experimental area was established with two cultivars of Panicum maximum Jacq. (Mombaca and Aruana, a hybrid cultivar of P. maximum Jacq. and P. Infestum BRA-7102 (Massai, two cultivars of Brachiaria brizantha (A. Rich. Stapf (Marandu and Xaraes and Molasses grass (Melinis minutiflora Beauv. and jaragua grass (Hyparrhenia rufa (Nees Stapf.. The grasses were planted in 1.0-m² experimental units with 24 plants arranged in a completely randomized block design with three replications. Growth pattern of the grasses was evaluated through mass development, tiller mortality, development stage and leaf longevity. Development patterns differed significantly among groups of grasses, indicating that the same available resources can be used in different manners by grasses from the same genus and/or species.Um experimento foi conduzido com o objetivo de avaliar o padrão de desenvolvimento de gramíneas forrageiras tropicais em crescimento livre por meio das características morfogênicas e estruturais, com expectativa de uso desse estudo no protocolo de avaliação de gramíneas forrageiras. A área experimental foi estabelecida com dois cultivares de Panicum maximum Jacq. (Mombaça e Aruana, um cultivar híbrido de P. maximum Jacq. e P. infestum BRA-7102 (Massai, dois cultivares de Brachiaria brizantha (A. Rich. Stapf (Marandu e Xaraés e com os capins gordura (Melinis minutiflora Beauv. e jaraguá (Hyparrhenia rufa (Nees Stapf.. As gramíneas foram plantadas em unidades experimentais de 1,0 m² com 24 plantas arranjadas em delineamento de blocos completos casualizados com três repetições. O padrão de desenvolvimento das gramíneas foi avaliado por meio do desenvolvimento de massa, da mortalidade de

  10. Production and quality of Mombaça grass forage under different residual heights

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    Ana Luiza Silva Carvalho

    2017-04-01

    Full Text Available This study was conducted to evaluate management strategies in Mombaça grass pastures (Panicum maximum under intermittent grazing subjected to different residual heights. A randomized-block design with two treatments (two post-grazing residual heights: 30 and 50 cm and three replications was adopted. Pasture heights pre- and post-grazing, forage mass and accumulation, rest and occupation periods, pasture morphological components, milk yield and quality forage were evaluated. The data were submitted to analysis of variance and the means were compared by the F test at 5% probability. A longer grazing interval was observed in the treatments under the more severe grazing intensity. For forage mass post-grazing, larger production and higher percentage of leaves were found with the 50 cm residue, as well as higher crude protein contents and digestibility of leaves and stems and lower lignin and neutral detergent fiber contents. The residual height of 50 cm is recommended for the management of Mombaça grass pasture, as it provides greater milk yield per animal and a larger number of grazing cycles, ensuring better use of the area.

  11. Availability and toxicity of cadmium to forage grasses grown in contaminated soil.

    Science.gov (United States)

    Silva, Enilson B; Fonseca, Felipe G; Alleoni, Luís R F; Nascimento, Sandra S; Grazziotti, Paulo H; Nardis, Bárbara O

    2016-09-01

    It is important to know the mechanisms for forage development, especially those related to the tolerance of potentially toxic elements, when considering their use in phytoremediation in heavy metal contaminated areas. In this study, we evaluated plant growth, concentration, and the availability of cadmium (Cd) for forage grasses (Panicum maximum Jacq. cv. Aruana and cv. Tanzânia; Brachiaria decumbens cv. Basilisk; Brachiaria brizantha cv. Xaraés and cv. Marandu) cultivated in Cd contaminated soils. The experiments were performed under greenhouse conditions over a 90-day evaluation period, and the Cd rates were 2, 4, and 12 mg/kg of soil. The relative growth rate of the forage grasses decreased as Cd rates increased, and the following descending order of susceptibility was observed: Marandu > Xaraés > Aruana > Tanzânia > Basilisk, with regard to phytotoxicity in these plants. The forage Cd concentration increased in line with increases in the Cd rates. Cd contents extracted by Mehlich-1 and by diethylenetriaminepentaacetic acid presented high positive correlation with forage relative growth. The forage plants did not block Cd entry into the food chain because they were not capable of limiting Cd absorption.

  12. ANÁLISE DE CRESCIMENTO EM CAPIM-TANZÂNIA NOS SISTEMAS DE PLANTIO SOLTEIRO E CONSÓRCIO COM LEGUMINOSAS GROWTH ANALYSIS OF TANZANIA GRASS DIFFERENT SISTEMS CROPPIN WITH LEGUMES

    Directory of Open Access Journals (Sweden)

    Tomas de Aquino Portes e Castro

    2007-07-01

    Full Text Available Este trabalho teve por objetivo avaliar o efeito da competição no crescimento da gramínea forrageira Panicum maximum Jacq. cv. Tanzânia em consórcio com as leguminosas forrageiras Stylosanthes guianensis cv. Mineirão e Neonotonia wightii cv. comum, nos sistemas de plantio solteiro e consórcio. O delineamento experimental foi o em blocos casualizados, com quatro repetições e os seguintes tratamentos: Tanzânia em sistema solteiro de plantio; Tanzânia em consórcio com soja perene; e Tanzânia em consórcio com estilozantes. Considerando que a TCC máxima (kg.ha-1.dia-1 do Tanzânia foi obtida aos 84 DAE, o IAF observado nessa mesma data correspondeu ao IAF ótimo. Isso demonstra que os consórcios não afetaram o ciclo dessa gramínea, mas sim no que se refere aos valores obtidos para TCC e IAF, principalmente no consórcio do Tanzânia com estilozantes. O baixo valor observado para Tanzânia no consórcio com soja perene evidencia o efeito de inibição mútua. Desse modo, em relação à TCC e MS, os baixos valores observados para a Tanzânia no consórcio com soja perene sugerem um efeito supressor, promovido pela referida leguminosa. PALAVRAS-CHAVES: Índice de área foliar (IAF, Neonotonia wightii, Panicum maximum, Stylosanthes guianensis, taxa de crescimento da cultura (TCC. This work aimed to evaluate the effect of the competition in the growth of the forage grasses Panicum maximum to Tanzânia cv. and two legumies forages Stylosanthes guianensis cv. Mineirão and Neonotonia wightii cv. Common, in the single and mixed crop systems. The experiment was carried out in a randomized block design with four replications and the treatments were: Tanzânia grass in a single crop system; Tanzânia grass in a mixed crop system with the Perennial Soy and Tanzânia grass in a mixed crop system with Stilozantes. Considering that maximum TCC (kg.ha-1.dia-1 of Tanzânia they were obtained 84 DAE, to leaf area index (IAF observed in this same

  13. Biomass and leaf-level gas exchange characteristics of three African savanna C4 grass species under optimum growth conditions

    NARCIS (Netherlands)

    Mantlana, K.B.; Veenendaal, E.M.; Arneth, A.; Grispen, V.; Bonyongo, C.M.; Heitkönig, I.M.A.; Lloyd, J.

    2009-01-01

    C4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration

  14. Degradation of Crude Protein in Groundnut Cake, Guinea Grass ...

    African Journals Online (AJOL)

    Three West African dwarf rams fitted with rumen cannula, were used in a completely randomized design for degradation of crude protein (CP) of groundnut cake (GNC), Panicum maximum, rumen epithelial scraping (RES), and diets containing increasing levels of RES. Concentrate diets were formulated such that 0% (A), ...

  15. Antihepatotoxic Effect and Metabolite Profiling of Panicum turgidum Extract via UPLC-qTOF-MS

    Science.gov (United States)

    Farag, Mohamed A.; El Fishawy, Ahlam M.; El-Toumy, Sayed A.; Amer, Khadiga F.; Mansour, Ahmed M.; Taha, Hala E.

    2016-01-01

    Background: Panicum turgidum, desert grass, has not reported any detailed phytochemical or biological study as yet Objective: To establish P. turgidum secondary metabolite profile and to assess its antihepatotoxic effect Materials and Methods: Ultra-performance liquid chromatography (UPLC) coupled to quadrupole high-resolution time of flight mass spectrometry (qTOF-MS) was used for large-scale secondary metabolites profiling in P. turgidum extract, alongside assessing median lethal dose (LD50) and hepatoprotective effect against carbon tetrachloride (CCl4) intoxication Results: A total of 39 metabolites were identified with flavonoids as the major class present as O/C-glycosides of luteolin, apigenin, isorhamnetin and naringenin, most of which are first time to be reported in Panicum sp. Antihepatotoxic effect of P. turgidum crude extract was revealed via improving several biochemical marker levels and mitigation against oxidative stress in the serum and liver tissues, compared with CCl4 intoxicated group and further confirmed by histopathological examination. Conclusion: This study reveals that P. turgidum, enriched in C-flavonoids, presents a novel source of safe antihepatotoxic agents and further demonstrates the efficacy of UPLC-MS metabolomics in the field of natural products drug discovery. SUMMARY UPLC coupled to qTOF-MS was used for large scale secondary metabolites profiling in P. turgidum.A total of 39 metabolites were identified with flavonoids amounting as the major metabolite class.Anti-hepatotoxic effect of P. turgidum extract was revealed via several biochemical markers and histopathological examination.This study reveals that P. turgidum, enriched in C-flavonoids, present a novel source of antihepatotoxic agents. Abbreviations used: UPLC: Ultra-performance liquid chromatography (UPLC), LD50: median lethal dose, MDA: malondialdehyde, GSH: glutathione reductase, CAT: catalase, SOD: superoxide dismutase, ALT: alanine aminotransferase, AST: aspartate

  16. Biomass accumulation and chemical composition of Massai grass intercropped with forage legumes on an integrated crop-livestock-forest system

    Directory of Open Access Journals (Sweden)

    Tatiana da Costa Moreno Gama

    2014-06-01

    Full Text Available The objective was to evaluate the use of woody legumes (Albizia lebbeck, Cratylia argentea, Dipteryx Allata (Baru, a Leucaena hybrid (L. leucocephala + L. diversifolia, and Leucaena leucocephalacv. Cunningham and herbaceous legumes (Arachis pintoi intercropped with Panicum maximum cv. Massai, simultaneously implanted in a maize crop. The study made use of a randomized block experimental design with four replications. Assessments of biomass accumulation and forage nutritional value were made after the maize harvest, between June 2008 and October 2010. It was found that the residues of maize provided better growing conditions for Massai grass during the dry season. L. leucocephala cv. Cunningham and the Leucaena hybrid had the highest accumulation of all forage legumes evaluated, and provided the best nutritional value of all the arrangements tested. Of all woody legumes tested in this system, Leucaena was considered feasible for intercropping with Massai grass. The intercrop of perennial woody Baru with maize is not recommended. Albizia lebbeck and Cratylia argentea require further study, especially the yield assessment at different cutting intervals and cutting heights. Arachis pintoi had a low participation in the intercropping, showing greater performance over time, indicating slow thriving in this experimental condition.

  17. The response of a Mombaça grass seed crop to timing and levels of boron fertilization

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    Gleice Menezes de Almeida

    2015-06-01

    Full Text Available Boron (B deficiency has been frequentely mentioned in crops of economic interest. This experiment aimed to evaluate the effects of two times (March 3 2008 and at anthesis and four doses of foliar application of B (equivalent to 0, 2, 4 and 6 kg ha-1 in Mombaça grass (Panicum maximum Jacq. cv. Mombaça on components of seed yield and quality, seed yield, and relationships among yield-components. The experimental design was a randomized block design in a factorial design (2x4, with four replications. The experiment was conducted in the field. The times and doses of B application had no effect on the mass of tillers vegetative and tillers with panicle, and numbers of vegetative tillers, tillers with panicle and total tillers. The interaction was significant in March 3, for the number of seeds apparent and pure, panicle-1 and area-1, apparent seed yield, pure seed yield, harvest index, germinable seed yield, and for a one thousand seeds pure. The times and doses of B did not affect the physical purity and seed germination. A high correlation was obtained between the number of apparent and pure seeds per area and harvest index, with apparent seed yield and with pure seed yield. Levels of foliar B fertilization of 4.0 kg ha-1 can be recommended to be applied in seed crops of Mombaça grass.

  18. Crescimento de gramíneas e leguminosas forrageiras tropicais sob sombreamento Growth of tropical forage grasses and legumes under shade

    Directory of Open Access Journals (Sweden)

    Carlos Mauricio Soares de Andrade

    2004-03-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de níveis de sombreamento artificial (0%, 30%, 50% e 70% nas taxas de acúmulo de matéria seca de quatro gramíneas (Brachiaria brizantha cv. Marandu, B. humidicola cv. Quicuio-da-amazônia, Panicum maximum cv. Massai e Paspalum notatum cv. Pensacola e três leguminosas forrageiras (Arachis pintoi cv. Belmonte, A. pintoi BRA-031143 e Pueraria phaseoloides, em Rio Branco, Acre. No período de novembro de 1999 a abril de 2001, foram realizados nove cortes para medição das taxas de acúmulo de matéria seca. Os capins marandu e massai tiveram o melhor desempenho entre as gramíneas, aliando boa tolerância ao sombreamento e alta capacidade produtiva, constituindo opções importantes na composição de sistemas silvipastoris em áreas com solos bem drenados. O quicuio-da-amazônia apresentou menor tolerância ao sombreamento, podendo ser usado em sistemas silvipastoris com baixa densidade arbórea, em áreas com chuvas bem distribuídas ou com solos mal drenados. O capim-pensacola apresentou alta tolerância ao sombreamento, mas baixa capacidade produtiva, não sendo recomendado para a região. O Arachis pintoi cv. Belmonte demonstrou maior capacidade produtiva e tolerância ao sombreamento que as demais leguminosas.The objective of this work was to evaluate the effect of levels of artificial shade (0%, 30%, 50% and 70% on dry matter accumulation rates of four tropical forage grasses (Brachiaria brizantha cv. Marandu, B. humidicola cv. Quicuio-da-amazônia, Panicum maximum cv. Massai and Paspalum notatum cv. Pensacola and three forage legumes (Arachis pintoi cv. Belmonte, A. pintoi BRA-031143 and Pueraria phaseoloides in Rio Branco, Acre, Brazil. To measure dry matter accumulation rates, nine cuts were performed between November 1999 and April 2001. The grasses Marandu and Massai had the best performance, with good shade tolerance and productivity, and were good options for silvopastoral systems in

  19. Nutritive Value of Grasses in Semi-arid Rangelands of Ethiopia: Local Experience Based Herbage Preference Evaluation versus Laboratory Analysis

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    Habtamu T. Keba

    2013-03-01

    Full Text Available We examined the nutritive value of common grass species in the semi-arid rangelands of Borana in southern Ethiopia using local experience based herbage preference (LEBHP perception and laboratory techniques. Local pastoralists in the study area were asked to identify common grass species and rank them according to the species’ preferences and palatability to cattle. The pastoralists listed a total of 15 common grass species which were then sampled during the main rain and cold dry seasons and analyzed for crude protein (CP, Neutral Detergent Fiber (NDF, Acid Detergent Fiber (ADF and ash content to verify pastoralists’ claim regarding the quality of individual species. The relative feed value (RFV and dry matter digestibility (DMD were also calculated using NDF and ADF contents. Spearman’s rank correlation was used to examine possible relationships between laboratory results and pastoralists’ experience on grass quality. Cenchrus ciliaris, Chrysopogon aucheri, Digitaria milanjiana, Eragrostis papposa and Panicum maximum were the top five species based on LEBHP perception. There were indications of inconsistency in terms of LEBHP perception among the different pastoral communities. The chemical composition of all grass species showed significant (p<0.05 variation between sites, seasons and species. The results showed that the CP values for the Borana rangelands were in the range of 8.7% in the main rain season to 5.1% for the cold dry season. The fiber constituents were relatively low in the main rain season compared to the cold dry season. Overall, Digitaria milanjiana had the highest CP (16.5% content, while the least was recorded with Heteropogon contortus (10.8 and Aristida adoensis (9.8% during the main rain season. It seems that the spatial variability of landscapes within the wider geographical regions, soil properties and texture, and land-use patterns probably contributed to site differences in species quality. Generally, the RFV

  20. Kangaroo grass

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-06

    Apr 6, 2009 ... in Australia (Hayman, 1960) and is often used as a forage species for domestic and wild animals. It is also found in some parts of Africa, Asia and the Pacific. It commonly grows in grassland and opens woodland communities. Kangaroo grass is a tufted perennial that can grow up to 1.5 m tall and 0.5 m ...

  1. Straw decomposition of nitrogen-fertilized grasses intercropped with irrigated maize in an integrated crop-livestock system

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    Cristiano Magalhães Pariz

    2011-12-01

    Full Text Available The greatest limitation to the sustainability of no-till systems in Cerrado environments is the low quantity and rapid decomposition of straw left on the soil surface between fall and spring, due to water deficit and high temperatures. In the 2008/2009 growing season, in an area under center pivot irrigation in Selvíria, State of Mato Grosso do Sul, Brazil, this study evaluated the lignin/total N ratio of grass dry matter , and N, P and K deposition on the soil surface and decomposition of straw of Panicum maximum cv. Tanzânia, P. maximum cv. Mombaça, Brachiaria. brizantha cv. Marandu and B. ruziziensis, and the influence of N fertilization in winter/spring grown intercropped with maize, on a dystroferric Red Latosol (Oxisol. The experiment was arranged in a randomized block design in split-plots; the plots were represented by eight maize intercropping systems with grasses (sown together with maize or at the time of N side dressing. Subplots consisted of N rates (0, 200, 400 and 800 kg ha-1 year-1 sidedressed as urea (rates split in four applications at harvests in winter/spring, as well as evaluation of the straw decomposition time by the litter bag method (15, 30, 60, 90, 120, and 180 days after straw chopping. Nitrogen fertilization in winter/spring of P. maximum cv. Tanzânia, P. maximum cv. Mombaça, B. brizantha cv. Marandu and B. ruziziensis after intercropping with irrigated maize in an integrated crop-livestock system under no-tillage proved to be a technically feasible alternative to increase the input of straw and N, P and K left on the soil surface, required for the sustainability of the system, since the low lignin/N ratio of straw combined with high temperatures accelerated straw decomposition, reaching approximately 30 % of the initial amount, 90 days after straw chopping.

  2. Grass Lignocellulose

    Science.gov (United States)

    Akin, Danny E.

    Grass lignocelluloses are limited in bioconversion by aromatic constituents, which include both lignins and phenolic acids esters. Histochemistry, ultraviolet absorption microspectrophotometry, and response to microorganisms and specific enzymes have been used to determine the significance of aromatics toward recalcitrance. Coniferyl lignin appears to be the most effective limitation to biodegradation, existing in xylem cells of vascular tissues; cell walls with syringyl lignin, for example, leaf sclerenchyma, are less recalcitrant. Esterified phenolic acids, i.e., ferulic and p-coumaric acids, often constitute a major chemical limitation in nonlignified cell walls to biodegradation in grasses, especially warm-season species. Methods to improve biodegradability through modification of aromatics include: plant breeding, use of lignin-degrading white-rot fungi, and addition of esterases. Plant breeding for new cultivars has been especially effective for nutritionally improved forages, for example, bermudagrasses. In laboratory studies, selective white-rot fungi that lack cellulases delignified the lignocellulosic materials and improved fermentation of residual carbohydrates. Phenolic acid esterases released p-coumaric and ferulic acids for potential coproducts, improved the available sugars for fermentation, and improved biodegradation. The separation and removal of the aromatic components for coproducts, while enhancing the availability of sugars for bioconversion, could improve the economics of bioconversion.

  3. The genetics of divergence and reproductive isolation between ecotypes of Panicum hallii

    Science.gov (United States)

    Lowry, David B; Hernandez, Kyle; Taylor, Samuel H; Meyer, Eli; Logan, Tierney L; Barry, Kerrie W; Chapman, Jarrod A; Rokhsar, Daniel S; Schmutz, Jeremy; Juenger, Thomas E

    2015-01-01

    The process of plant speciation often involves the evolution of divergent ecotypes in response to differences in soil water availability between habitats. While the same set of traits is frequently associated with xeric/mesic ecotype divergence, it is unknown whether those traits evolve independently or if they evolve in tandem as a result of genetic colocalization either by pleiotropy or genetic linkage. The self-fertilizing C4 grass species Panicum hallii includes two major ecotypes found in xeric (var. hallii) or mesic (var. filipes) habitats. We constructed the first linkage map for P. hallii by genotyping a reduced representation genomic library of an F2 population derived from an intercross of var. hallii and filipes. We then evaluated the genetic architecture of divergence between these ecotypes through quantitative trait locus (QTL) mapping. Overall, we mapped QTLs for nine morphological traits that are involved in the divergence between the ecotypes. QTLs for five key ecotype-differentiating traits all colocalized to the same region of linkage group five. Leaf physiological traits were less divergent between ecotypes, but we still mapped five physiological QTLs. We also discovered a two-locus Dobzhansky–Muller hybrid incompatibility. Our study suggests that ecotype-differentiating traits may evolve in tandem as a result of genetic colocalization. PMID:25252269

  4. Global changes in mineral transporters in tetraploid switchgrasses (Panicum virgatum L.

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    Nathan A. Palmer

    2014-01-01

    Full Text Available Switchgrass (Panicum virgatum L is perennial, C4 grass with great potential as a biofuel crop. An in-depth understanding of the mechanisms that control mineral uptake, distribution and remobilization will benefit sustainable production. Nutrients are mobilized from aerial portions to below-ground crowns and rhizomes as a natural accompaniment to above-ground senescence post seed-set. Mineral uptake and remobilization is dependent on transporters, however, little if any information is available about the specific transporters that are needed and how their relative expression changes over a growing season. Using well-defined classes of mineral transporters, we identified 520 genes belonging to 40 different transporter classes in the tetraploid switchgrass genome. Expression patterns were determined for many of these genes using publically available transcriptomic datasets obtained from both greenhouse and field grown plants. Certain transporters showed strong temporal patterns of expression in distinct developmental stages of the plant. Gene-expression was verified for selected transporters using qRT-PCR. By and large these analyses confirmed the developmental stage-specific expression of these genes. Mineral analyses indicated that K, Fe, Mg, Co and As had a similar pattern of accumulation with apparent limited remobilization at the end of the growing season. These initial analyses will serve as a foundation for more detailed examination of the nutrient biology of switchgrass.

  5. Effect of pollination mode on progeny of Panicum coloratum var. makarikariense: Implications for conservation and breeding

    Directory of Open Access Journals (Sweden)

    Lorena V. Armando

    2017-09-01

    Full Text Available Panicum coloratum var. makarikariense, a perennial grass native to Africa, is adapted to a wide range of soil and climatic conditions with potential to be used as forage in tropical and semi-arid regions around the world. Our objective was to understand how the pollination mode affects viable seed production and further survival of the progeny. We evaluated self- and open-pollinated progenies from different accessions by measuring the seed production of the parents and their germination performance, germination rate and seedling survival. Parents and progeny were also fingerprinted with Simple Sequence Repeats (SSR. Progeny produced through open-pollination resulted in significantly more filled seeds and superior seedling survival than self-pollination. These results indicate that accessions studied here rely heavily on cross-pollination, whereas the contribution of self-pollinated offspring to the population is likely to be low. SSR profiles showed that, on average, 85% of the progeny (arising from cross-pollination possessed paternal specific markers and 100% of them were genetically different from the maternal genotype. All plants examined had 4x = 36 chromosomes. Overall, our findings indicate that var. makarikariense is able to generate highly polymorphic progeny through segregation and recombination. This study provides reference information for the formulation of appropriate strategies for pasture germplasm management, conservation and development of breeding programs. 

  6. Accelerating the Switchgrass (Panicum virgatum L.) Breeding Cycle Using Genomic Selection Approaches

    Science.gov (United States)

    Lipka, Alexander E.; Lu, Fei; Cherney, Jerome H.; Buckler, Edward S.; Casler, Michael D.; Costich, Denise E.

    2014-01-01

    Switchgrass (Panicum virgatum L.) is a perennial grass undergoing development as a biofuel feedstock. One of the most important factors hindering breeding efforts in this species is the need for accurate measurement of biomass yield on a per-hectare basis. Genomic selection on simple-to-measure traits that approximate biomass yield has the potential to significantly speed up the breeding cycle. Recent advances in switchgrass genomic and phenotypic resources are now making it possible to evaluate the potential of genomic selection of such traits. We leveraged these resources to study the ability of three widely-used genomic selection models to predict phenotypic values of morphological and biomass quality traits in an association panel consisting of predominantly northern adapted upland germplasm. High prediction accuracies were obtained for most of the traits, with standability having the highest ten-fold cross validation prediction accuracy (0.52). Moreover, the morphological traits generally had higher prediction accuracies than the biomass quality traits. Nevertheless, our results suggest that the quality of current genomic and phenotypic resources available for switchgrass is sufficiently high for genomic selection to significantly impact breeding efforts for biomass yield. PMID:25390940

  7. Plot-size for 15N-fertilizer recovery studies by tanzania-grass

    International Nuclear Information System (INIS)

    Martha Junior, Geraldo Bueno; Trivelin, Paulo Cesar Ocheuze; Corsi, Moacyr

    2009-01-01

    The understanding of the N dynamics in pasture ecosystems can be improved by studies using the 15 N tracer technique. However, in these experiments it must be ensured that the lateral movement of the labeled fertilizer does not interfere with the results. In this study the plot-size requirements for 15 N-fertilizer recovery experiments with irrigated Panicum maximum cv. Tanzania was determined. Three grazing intensities (light, moderate and intensive grazing) in the winter, spring and summer seasons were considered. A 1 m 2 plot-size, with a grass tussock in the center, was adequate, irrespective of the grazing intensity or season of the year. Increasing the distance from the area fertilized with 15 N negatively affected the N derived from fertilizer (Npfm) recovered in herbage.The lowest decline in Npfm values were observed for moderate and light grazing intensities. This fact might be explained by the vigorous growth characteristics of these plants. Increasing the grazing intensity decreased the tussock mass and, the smaller the tussock mass, the greater was the dependence on fertilizer nitrogen. (author)

  8. Avaliação de gramíneas forrageiras na região sul de Minas Gerais Evaluation of forage grasses for the south region of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Milton de Andrade Botrel

    1999-04-01

    Full Text Available Foram conduzidos dois experimentos na região do sul de Minas Gerais para avaliar o potencial de gramíneas forrageiras. No experimento 1 foram avaliadas as seguintes espécies, consideradas de baixa exigência nutricional: Andropogon gayanus, Kunt; Brachiaria brizantha, Stapf; Brachiaria decumbens, Stapf; Brachiaria ruziziensis, Germain Evrard; Brachiaria humidicola (Rendle Schweickt e Melinis minutiflora, Beauv. No experimento 2 foram avaliadas as gramíneas consideradas de média e alta exigência nutricional, a saber: Setaria sphacelata (Schum. Moss; Hemarthria altissima (Poir. Stapf; Chloris gayana, Kunt; Cynodon nlemfuensis, Vanderyst var. nlemfuensis; Hyparrhenia rufa, (Ness Stapf. e as cultivares de Panicum maximum, Jacq.: Tobiatã, Green Panic e Makueni. O delineamento experimental foi de blocos ao acaso com três repetições. Os níveis de calagem e de adubação para estabelecimento e manutenção foram diferenciados para os dois experimentos. Cada espécie foi avaliada nos seguintes aspectos: produção de forragem e teor de proteína bruta no período da seca e das chuvas e cobertura vegetal do solo. As gramíneas do experimento 1 que se destacaram na maioria dos aspectos avaliados foram: B. brizantha, B. decumbens, A. gayanus enquanto que no experimento 2 as espécies que apresentaram maior potencial forrageiro foram: S. sphacelata, P. maximum cv. Tobiatã.experiments were undertaken in the South region of Minas Gerais State, Brazil, to evaluate the yield potential of forage grasses. In experiment 1, the following species, considered as having low nutritional requirements, were evaluated: Andropogon gayanus, Kunt; Brachiaria brizantha, Stapf; Brachiaria decumbens, Stapf; Brachiaria ruziziensis, Germain Evrard; Brachiaria humidicola (Rendle Schweickt and Melinis minutiflora, Beauv. In experiment 2, the species considered as having medium and high nutritional requirements, that is: Setaria sphacelata (Schum.; Hemarthria altissima

  9. Estabelecimento de pastagem de capim-tanzânia usando milheto como cultura acompanhante The establishment of tanzania grass pasture using millet as a companion crop

    Directory of Open Access Journals (Sweden)

    Marcos Carvalho Maia

    2000-10-01

    Full Text Available Este estudo objetivou avaliar o rendimento e a composição química da forragem de milheto e de capim-tanzânia, a primeira espécie como cultura companheira, na formação de pastagem da gramínea perene Panicum maximum Jacq. cv. Tanzânia I, bem como a viabilidade do emprego desta prática. Os tratamentos avaliados foram quatro combinações de mistura de sementes, numa densidade de semeadura básica de 8 kg/ha, de capim-tanzânia/milheto: (08/00; 05/03; 04/04 e 03/05 kg/ha e três freqüências de corte (três cortes -- 40, 70 e 100 dias após a semeadura; dois cortes -- 50 e 100 dias após a semeadura; um corte -- 100 dias após a semeadura, no delineamento de blocos ao acaso, em esquema de parcelas subdivididas. As densidades de semeadura foram alocadas nas parcelas principais e as freqüências de cortes nas subparcelas. As produções de MS da associação entre milheto e capim-tanzânia foram maiores que as do capim-tanzânia exclusivo. A concentração de PB na MS de ambas as espécies aumentou, ao passo que os teores de FDN e FDA reduziram, com o aumento do número de cortes, porém, na consorciação, verificam-se valores semelhantes nos teores destas variáveis e pequena redução no teor de PB, quando comparados aos teores do capim-tanzânia exclusivo. Com base nestes resultados, conclui-se que é viável a formação de pastagem do capim-tanzânia usando o milheto como cultura acompanhante.The objective was to evaluate the forage yield and chemical composition of millet and Tanzania grass, the first one as a companion crop, in the formation of the Panicum maximum Jacq. cv. Tanzania I pasture, as well as the viability of the use of this practice. The evaluated treatments were four seed mixture combinations based on sowing density of 8 kg/ha of Tanzania grass/millet (08/00; 05/03; 04/04 and 03/05 kg/ha and three cutting frequencies (three cuttings - 40, 70 and 100 days after sowing, two cuttings - 50 and 100 days after sowing; one

  10. Invertebrate fauna associated with Torpedograss, Panicum repens (Cyperales: Poaceae), in Lake Okeechobee, Florida, and prospects for biological control

    International Nuclear Information System (INIS)

    Cuda, J.P.; Dunford, J.C.; Leavengood, J.M. Jr.

    2007-01-01

    Torpedograss, Panicum repens L., is an adventive, rhizomatous grass species that has become an invasive weed of terrestrial, wetland, and aquatic environments in tropical and subtropical regions worldwide. Until recently, strategies for controlling torpedograss in the USA have focused almost exclusively on mechanical and chemical methods, either alone or in combination, with varied results. A survey of the arthropods and nematodes currently associated with the plant in Lake Okeechobee, Florida, was conducted as part of a feasibility study to determine whether torpedograss is an appropriate target for a classical biological control program. Overall, approximately 4,000 arthropods and 400 nematode specimens were collected. Sweep, clipped vegetation, and soil core samples were dominated by representatives of the arthropod orders Hemiptera, Hymenoptera, Diptera, and Acari. Lesion nematodes of the genus Pratylenchus were commonly associated with the roots of torpedograss. None of the organisms collected were torpedograss specialists. Although classical biological control of torpedograss is feasible based on the extent of the infestation, economic losses, resistance to conventional controls, and the report of a potentially host specific natural enemy in India, the botanical position of this grass weed will require a formal risk assessment before proceeding with a classical biological control program. (author) [es

  11. Establishment, Growth and Biomass yield of three Grass species on a degraded Ultisol and their effect on soil loss.

    Directory of Open Access Journals (Sweden)

    2016-11-01

    Full Text Available Erosion is a cause for concern; this is because of its effects on the soil used for both agricultural and non-agricultural purposes. Experiments were carried out to check the establishment, growth and biomass field of 3 tropical plants and their effects on soil loss during 2007 planting season. The treatments comprised 3 grasses viz. Azonopus compressus. Panicum maximum and Andropogon gayanus. The grasses were laid our in the field using a randomized complete block design replicated 4 times. Bare soil was used as the control. The parameters tested were plant height, leaf area index, root density, root establishment and the amount of soil loss using erosion pins. The result showed that Andropogon gayanus has an edge over Panicum maximum and Axonopus compressus with reference to plant height, root establishment, root density and leaf area index. Andropogon gayanus had a higher plant height from 3,6,9 and 12WAP with plant heights of 3.30cm, 3.63cm,3.93cm and 4.30cm representing 15.7%, 19.3% and 28.8% respectively. It was followed by P. maximum while A. compressus maintained the lowest plant height from 3,6,9 and 12 WAP with plant height of 2.83cm, 3.05cm, 3.20cm and 3.45cm respectively. In terms of root density, A. compressus did not have much root density which was 0.02t/ha, also at 12WAP, P. maximum did not have much root density which was 0.06t/ha though it was higher than A. compressus. The trend was the same for A. gayanus whose root density was 0.75t/ha. In terms of leaf area index (LAI, it was shown that at 3WAP and 6WAP, A. compressus had the lowest leaf area index of 58.25 and 65.75 respectively. Also at 9WAP and 12WAP A. compressus had 72.28 and 75.08t/ha respectively. At 3WAP and 6WAP P.maximum had a high leaf area index of 66.60 and 77.25 respectively. A. gayanus at 3WAP and 6WAP had 87.73 gayanus at 3WAP and 6WAP had 87.73 and 90.80 for 9WAP and 12WAP respectively. A. compressus protected the soil, reducing soil loss as a total of 9

  12. Lipid composition of grains from wild grasses

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    Zydgalo, J. A.

    1995-02-01

    Full Text Available Physicochemical characteristics, fatty acid and sterol composition were studied in grains of Agropyron elongatum, Bromus catharticus, Festuca arundinacea, Stipa hyaline and Panicum maximum. The highest protein level was found in A. elongatum. Linoleic and palmitic acids were the predominant fatty acids in all species, β-sitosterol was by far the most prominent sterol component in all samples, while Δ7-stigmasterol was detected in only trace amounts.

    Se estudió las características físico-químicas, la composición de ácidos grasos y esteroles de Agropyron elongatum, Bromus catharticus, Festuca arundinacea, Stipa hialina y Panicum maximum. Los niveles más altos de proteínas fueron encontrados en A. elongatum. Dentro de los ácidos grasos el linoleico y el palmítico fueron los predominantes. En todas las muestras el β-sitosterol fue el esterol que se presentó en mayor cantidad, mientras que el Δ7-estigmasterol fue detectado en cantidades trazas.

  13. Download this PDF file

    African Journals Online (AJOL)

    , Hyparrhenia (Hyparrhenia mfa), Guine grass (Panicum maximum) and sporobolus (Sporobolus pyramidalis) were ... demonstrated the benefits of field borders of napier grass (Pennisetum purpureum) and Sudan grass (Sorghum vulgare ...

  14. Croissance pré-sevrage des cobayes nourris au Panicum maximum ...

    African Journals Online (AJOL)

    L'objectif de ce travail est donc d'améliorer l'alimentation de ces animaux à travers la diversification des sources de protéine de la ration. Pour cet essai, 48 femelles ont préalablement été mises en croisement avec 8 mâles pendant une période de 31 jours selon un dispositif factoriel de quatre lots comptant 12 femelles ...

  15. An evaluation of Panicum maximum cv. Gatton: 2. The influence of ...

    African Journals Online (AJOL)

    -N) levels and higher acetic:propionic acid ratios. This trend was noted in all seasons. The nutritional value of the pasture in summer was high enough to meet at least the maintenance requirements of sheep in all stages of maturity evaluated.

  16. An evaluation of Panicum maximum cv. Gatton: 2. The influence of ...

    African Journals Online (AJOL)

    Unknown

    maturity on diet selection, intake and rumen fermentation in sheep. E.A. Relling, W.A. ... The stage of maturity of pasture influences forage quality and hence voluntary intake and selection by sheep. ..... dry matter production of some improved pastures and animal performance in relation to chemical composition in Malawi.

  17. Níveis de silicato de cálcio e magnésio na produção das gramídeas Marandu e Tanzânia cultivadas em um Neossolo Quartzarênico Level of calcium and magnesium silicate in the yield of Marandu grass and Tanzania grass cultivated in one Quartzsandy Neosoil

    Directory of Open Access Journals (Sweden)

    Caio Augustus Fortes

    2008-02-01

    Full Text Available O estudo foi conduzido em casa-de-vegetação do Departamento de Ciência do Solo da Universidade Federal de Lavras, Lavras-MG, com o objetivo de avaliar o efeito da correção da acidez do solo, por meio da aplicação de níveis de silicato de Ca e Mg, na produção das gramíneas Brachiaria brizantha cv. Marandu e Panicum maximum cv. Tanzânia-1 cultivadas em solo Neossolo Quartzarênico ortic. O delineamento experimental utilizado foi blocos ao acaso, em esquema fatorial 2 x 5 com quatro repetições, sendo duas forrageiras e cinco níveis de saturação por bases (V% original, 40, 60, 80 e 100%. Cada unidade experimental correspondeu a um vaso sem furos, com capacidade para 4,0 dm³ de solo, totalizando 40 vasos. Foram avaliadas as produções de MS por corte (PMS e total (PTMS, a altura e o número de perfilhos. Não houve variação entre as gramíneas em altura de perfilhos. O Tanzânia foi superior ao Marandu em PMS e número de perfilhos. Houve aumento linear na PMS, PTMS e altura de perfilhos. Conclui-se que ambas as gramíneas responderam de forma positiva à elevação dos níveis de V%, em PMS, até 54,8%. O Tanzânia produziu mais MS em relação ao Marandu.This study was conducted in a greenhouse of the Soil Science Department at Universidade Federal de Lavras, Lavras-MG, with the purpose of evaluating the effect of the soil correction acidity, by the application of Ca and Mg silicate levels, in the production of grasses Brachiaria brizantha cv. Marandu and Panicum maximum cv. Tanzânia-1 cultivated in Quartzsandy Neosoil ortic. The experimental design was a randomized complete block, in 2 x 5 factorial scheme with four replicates, being two forages and five levels of base saturation (BS%; (original BS, 40, 60, 80 and 100%. Each experimental unit corresponded to a pot with a capacity of 4.0 dm³ of soil, totalizing 40 pots. The dry matter yield (DMY for cut and total (TDMY, height and number of tillers were evaluated. There were

  18. The effect of fire on germination in five common veld grasses. | P.J.K. ...

    African Journals Online (AJOL)

    The effect of fire on the germination of Themeda triandra, Heteropogon contortus, Panicum maximum, Aristida junciformis and Sporobolus africanus was investigated. Seeds exposed directly to the fire were destroyed in all species. The germination of seeds buried (7 to 9 mm) when exposed to fire was depressed in T.

  19. Grass assemblages and diversity of conservation areas on the coastal plain south of Maputo Bay, Mozambique

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    S. J. Siebert

    2004-09-01

    Full Text Available A floristic analysis of the grass species assemblages of the Licuati Forest and Maputo Elephant Reserves south of Maputo Bay, Mozambique, is presented. Sampling of grass data was undertaken in six previously described, major vegetation types. TWINSPAN divisions distinguished grass assemblages that are characteristic for these major vegetation types of the study area. The results were supported by an Indirect Gradient Analysis. Further TWINSPAN divisions of a larger Maputaland data set indicated a floristic relationship between grass assemblages of similar major vegetation types in the study area and South Africa. This relationship was supported by high similarity values (> 65%, obtained with Sorenson's Coefficient. The coefficient also indicated varying degrees of similarity between grass assemblages of different major vegetation types within the study area. A rich diversity of 115 grass species and infraspecific taxa was recorded for the study area. The Chloridoideae and Panicoideae dominate the grass diversity and the genera with the most species include Eragrostis, Panicum and Digitaria. Most grass species in the study area are perennials and have a tufted growth form, but this varies considerably between vegetation types.

  20. The influence of phosphorus nutritional status on the uptake of germanium in Panicum miliaceum and Brassica alba

    Science.gov (United States)

    Kaden, Ute Susanne; Székely, Balázs; Wiche, Oliver

    2015-04-01

    In order to investigate the influence of the phosphorus nutritional status on the uptake of germanium (Ge) in biomass two species, white millet (Panicum miliaceum) and white mustard (Brassica alba) were grown and sampled in a greenhouse experiment. The cultivation took place on two different substrates. The plants were fertilized with different nutrient solutions which differed in their phosphate content, and artificial addition of Ge was held via the casting solution. During the test period, measurements of the pH value, electric conductivity, and phosphate content of the soil solution were conducted. To transfer germanium from soil and plant material in solution, melting and microwave digestion processes were done. The experiment showed that in both species the additional Ge supply also leads to an increasing germanium content in the aboveground plant material. The two species, however, behave differently in response to this Ge supply. Panicum miliaceum accumulates Ge in the above-ground parts of plants stem, leaf and fruit to a much greater extent than Brassica alba. On the other hand the Ge accumulation in the roots of both B. alba and P. miliaceum was very high. In case of B. alba the root content was found by far higher as compared to the other parts of the plant. The addition of phosphate in the system changes the behavior. Without additional Ge its natural uptake from soil decreases in both species but in B. alba it is more characteristic. Increasing Ge supply (for both species) leads to an increased Ge uptake, until it reaches a maximum, regardless of the presence of phosphate addition. Phosphate, on the other hand, has positive effects on Ge uptake only in the case of B. alba roots, and to a limited extent in roots of P. miliaceum. In addition, for Panicum miliaceum an increase of germanium mainly in the underground parts was achieved. A further addition of phosphate did not have a positive effect on a greater enrichment of germanium. Whereas in Brassica

  1. Morphogenetic characteristics and management of Tanzania grass Características morfogenéticas e manejo de capim-tanzânia

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    Patricia Menezes Santos

    2003-08-01

    Full Text Available The objective of this work was to evaluate the effect of grazing interval and period of evaluation over tissue turnover in Tanzania grass pastures (Panicum maximum cv. Tanzania and to ascertain if herbage accumulation rate can be used as a criterion to establish a defoliation schedule for this grass in Southeast of Brazil. A randomized block design with a split-plot arrangement was used. The effect of three grazing intervals was evaluated within seven periods between October 1995 and September 1996. Responses monitored were leaf and stem elongation rates, leaf senescence rate, stem length, and tiller density. Net herbage accumulation rate was calculated using tissue turnover data. The grazing intervals for Tanzania grass should be around 38 days between October and April (spring and early autumn and 28 days during the reproductive phase of the grass (April/May. Between May and September (late autumn and winter, grazing interval should be around 48 days. Herbage accumulation rate is not a good criterion to establish defoliation time for Tanzania grass. Studies on the effects of stem production in grazing efficiency, animal intake and forage quality are needed to improve Tanzania grass management.O objetivo deste trabalho foi avaliar o efeito do intervalo entre pastejos e do período de avaliação sobre algumas características morfogenéticas do capim-tanzânia (Panicum maximum cv. Tanzânia e verificar se o manejo desse capim pode ser baseado na taxa de acúmulo de matéria seca na região Sudeste do Brasil. Foi utilizado um delineamento de blocos completos ao acaso com parcelas subdivididas no tempo. Foi avaliado o efeito de três intervalos entre pastejos e de sete períodos de avaliação entre outubro de 1995 e setembro de 1996 sobre: taxa de alongamento foliar e dos colmos, taxa de senescência foliar, altura dos colmos e densidade populacional de perfilhos. Essas informações permitiram determinar a taxa líquida de acúmulo de mat

  2. Targeted mutagenesis in tetraploid switchgrass (Panicum virgatum L.) using CRISPR/Cas9.

    Science.gov (United States)

    Liu, Yang; Merrick, Paul; Zhang, Zhengzhi; Ji, Chonghui; Yang, Bing; Fei, Shui-Zhang

    2018-02-01

    The CRISPR/Cas9 system has become a powerful tool for targeted mutagenesis. Switchgrass (Panicum virgatum L.) is a high yielding perennial grass species that has been designated as a model biomass crop by the U.S. Department of Energy. The self-infertility and high ploidy level make it difficult to study gene function or improve germplasm. To overcome these constraints, we explored the feasibility of using CRISPR/Cas9 for targeted mutagenesis in a tetraploid cultivar 'Alamo' switchgrass. We first developed a transient assay by which a non-functional green-fluorescent protein gene containing a 1-bp frameshift insertion in its 5' coding region was successfully mutated by a Cas9/sgRNA complex resulting in its restored function. Agrobacterium-mediated stable transformation of embryogenic calli derived from mature caryopses averaged a 3.0% transformation efficiency targeting the genes of teosinte branched 1(tb1)a and b and phosphoglycerate mutase (PGM). With a single construct containing two sgRNAs targeting different regions of tb1a and tb1b genes, primary transformants (T0) containing CRISPR/Cas9-induced mutations were obtained at frequencies of 95.5% (tb1a) and 11% (tb1b), respectively, with T0 mutants exhibiting increased tiller production. Meanwhile, a mutation frequency of 13.7% was obtained for the PGM gene with a CRISPR/Cas9 construct containing a single sgRNA. Among the PGM T0 mutants, six are heterozygous and one is homozygous for a 1-bp deletion in the target region with no apparent phenotypical alterations. We show that CRISPR/Cas9 system can generate targeted mutagenesis effectively and obtain targeted homozygous mutants in T0 generation in switchgrass, circumventing the need of inbreeding. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  3. Perfilhamento e características estruturais do capim-Mombaça, adubado com fontes de fósforo, em pastejo = Tillering and structural characteristics of Mombaça grass fertilized with phosphate sources, under grazing

    Directory of Open Access Journals (Sweden)

    Ulysses Cecato

    2008-01-01

    Full Text Available O experimento foi realizado no período de dezembro de 2002 a abril de 2003, com o objetivo de avaliar o efeito de diferentes fontes de fósforo (termofosfato magnesiano YoorinÒ, fosfato natural de Gafsa, um formulado de superfosfato simples + superfosfato triplo e tratamento-controle, sem aplicação de fósforo em função dos meses de avaliação, sobre o índice de área foliar (IAF, peso e número de perfilhos, percentagem de lâmina foliares e colmo totais (%, razão lâmina foliar/colmo, no capim-Mombaça (Panicum maximum Jacq. cv. Mombaça. O delineamento experimental utilizado foi em blocos aoacaso com três repetições. As fontes de fósforo influenciaram (p The experiment was conducted from December/2002 to April/2003, with the objective of evaluating the effects of different phosphate sources (Yoorin magnesium thermophosphate, Simple Superphosphate +Triple Superphosphate, Gafsa natural phosphate, and control – no phosphate application as a function of the evaluation months, on leaf area index (LAI, tiller weight (P and number, percentage of total leaf and stem (% and leaf blade/stem ratio of Mombaça grass (Panicum maximum Jacq. cv. Mombaça. The experiment design was a randomized block, with three replications. Phosphate sources influenced (p < 0.05 the weight and number of tillers, while YoorinÒ had less weight per tiller, and the Gafsa phosphate obtained the lowest number of tillers. There was a period effect (p < 0.05 for all evaluated variables. The lowest LAI was observed in April, and the highest in February, showing adaptation to a new reproductive cycle. There was little phosphorous influence on tillering; however, soluble phosphate increased the weight of tillers, while the period increased leaf presence.

  4. GRASS SPECIES FROM C-4 CARBON FIXATION GROUP: POLISH EXPERIMENT WITH A NOVEL ENERGY AND FORAGE PURPOSES CROP

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    Włodzimierz Majtkowski

    2010-02-01

    Full Text Available Experiment was conducted during four years 2003-2006. Materials used were three genus grass species of C-4 photosynthesis: Andropogon gerardi Vitman, Panicum virgatum L. and Miscanthus sacchariflorus (Maxim. Hack. Plants were planted at spring 1998. Agrotechnical part of experiment was conducted in Botanical Garden of Plant Breeding Acclimatization Institute in Bydgoszcz and analytical part in Department of Animal Nutrition and Feed Management, Faculty of Animal Breeding and Biology of University of Technology and Life Science in Bydgoszcz. Forage from grass C-4 photosynthesis were material of good ensilage suitability. High structural carbohydrates (NDF, ADF contents in tested forage dry matter suggest ensilage at early phases of plant development. Above results suggest to possibility of usage of forage from grass C-4 carbon fixation group for animal feeding purposes. C-4 grass forage should be recognized as a supplementary source of green matter in periods of insufficient access to traditional silage sources.

  5. Ontogenesis and nutritive value of warm-season perennial bunch grasses

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    Robert D. Ziehr

    2014-06-01

    Full Text Available Understanding the dynamics of nutritive values in warm-season perennial bunch grasses with change in ontogenesis is essential to managing their use as forage for livestock or cellulosic bioenergy feedstock. Accumulated growth (not previously harvested of Alamo lowland and accession 9065018 upland switch grass (Panicum virgatum, Lometa Indian grass (Sorghastrum nutans, Earl big bluestem (Andropogon gerardii, San Marcos eastern gama grass (Tripsacum dactyloides and Haskell sideoats grama (Bouteloua curtipendula , all native to the southern Great Plains of North America, as well as Selection 75 Klein grass (Panicum coloratum, originating in southern Africa but selected in North America, was harvested every 28 d for 3 yr, commencing 1 yr after establishment. Growth stage, crude protein (CP and in vitro dry matter disappearance (IVDMD over 48 h were evaluated at each date. Some entries, such as Haskell, San Marcos and Selection 75, initiated reproductive growth earlier in the growing season and had higher nutritive value [up to 119 g CP/kg dry matter (DM and 630 g IVDMD/kg DM] at seed set than those reproducing later in the season. Nutritive value of San Marcos and Selection 75 responded to autumn rainfall with resurging nutritive value (over 100 g CP/kg DM and over 600 g IVDMD/kg DM, whereas others did not. These nuances in nutritive value may be useful in manipulating species composition and season of utilization for grazing bunch grasses, especially when incorporated into opportunistic harvests of bioenergy feedstock. Normal 0 false false false EN-US X-NONE X-NONE

  6. Controle químico de Panicum repens e Paspalum repens Chemical control of Panicum repens and Paspalum repens

    Directory of Open Access Journals (Sweden)

    C.A. Carbonari

    2004-09-01

    Full Text Available Panicum repens e Paspalum repens são espécies infestantes de ambientes úmidos e alagados, freqüentes em margens de lagos, reservatórios, canais de irrigação e drenagem. O presente trabalho teve como objetivo avaliar a eficiência de diferentes herbicidas no controle dessas duas espécies. O experimento foi conduzido no Núcleo de Pesquisas Avançadas em Matologia, do Departamento de Produção Vegetal, pertencente à Faculdade de Ciências Agronômicas/UNESP, campus de Botucatu-SP. As plantas foram cultivadas em caixas d'água e as pulverizações foram realizadas utilizando-se um pulverizador costal pressurizado a CO2. Os tratamentos testados foram: glyphosate a 2.400, 3.360 e 4.320 g e.a. ha-1 + Aterbane 0,5% v/v, glyphosate a 2.400, 3.360 e 4.320 g e.a. ha-1 + Silwet 0.1% v/v, imazapyr a 750 e 1.500 g e.a. ha-1 e diquat a 400 e 800 g i.a. ha-1 (em aplicações seqüenciais de 200+200 g i.a. ha-1 e 400+400 g i.a. ha-1, além de uma testemunha sem aplicação de herbicidas. O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições. Avaliações visuais de controle foram realizadas, sendo a massa seca das plantas determinada ao final do estudo. O herbicida glyphosate na dose de 4.320 g e.a. ha-1, independentemente do adjuvante utilizado, assim como na dose de 3.360 g e.a. ha-1 com Aterbane, proporcionou bom controle de Panicum repens e, em todas as doses e adjuvantes testados, promoveu controle excelente de Paspalum repens. O herbicida imazapyr, independentemente da dose testada, apresentou resultados insatisfatórios no controle das plantas de Panicum repens, porém promoveu um excelente controle de Paspalum repens; o herbicida diquat, apesar das duas aplicações e independentemente da dose utilizada, mostrou-se ineficiente para controle das duas espécies.Two experiments were carried out to evaluate the susceptibility of Panicum repens and Paspalum repens Bergius to different herbicides applied in

  7. Improved tissue culture conditions for the emerging C4model Panicum hallii.

    Science.gov (United States)

    Grant, Joshua N; Burris, Jason N; Stewart, C Neal; Lenaghan, Scott C

    2017-04-27

    Panicum hallii Vasey (Hall's panicgrass) is a compact, perennial C 4 grass in the family Poaceae, which has potential to enable bioenergy research for switchgrass (Panicum virgatum L.). Unlike P. hallii, switchgrass has a large genome, allopolyploidy, self-incompatibility, a long life cycle, and large stature-all suboptimal traits for rapid genetics research. Herein we improved tissue culture methodologies for two inbred P. hallii populations: FIL2 and HAL2, to enable further development of P. hallii as a model C 4 plant. The optimal seed-derived callus induction medium was determined to be Murashige and Skoog (MS) medium supplemented with 40 mg L -1 L-cysteine, 300 mg L -1 L-proline, 3% sucrose, 1 g L -1 casein hydrolysate, 3 mg L -1 2,4-dichlorophenoxyacetic acid (2,4-D), and 45 μg L -1 6-benzylaminopurine (BAP), which resulted in callus induction of 51 ± 29% for FIL2 and 81 ± 19% for HAL2. The optimal inflorescence-derived callus induction was observed on MP medium (MS medium supplemented with 2 g L -1 L-proline, 3% maltose, 5 mg L -1 2,4-D, and 500 μg L -1 BAP), resulting in callus induction of 100 ± 0.0% for FIL2 and 84 ± 2.4% for HAL2. Shoot regeneration rates of 11.5 ± 0.8 shoots/gram for FIL2 and 11.3 ± 0.6 shoots/gram for HAL2 were achieved using seed-induced callus, whereas shoot regeneration rates of 26.2 ± 2.6 shoots/gram for FIL2 and 29.3 ± 3.6 shoots/gram for HAL2 were achieved from inflorescence-induced callus. Further, cell suspension cultures of P. hallii were established from seed-derived callus, providing faster generation of callus tissue compared with culture using solidified media (1.41-fold increase for FIL2 and 3.00-fold increase for HAL2). Aside from abbreviated tissue culture times from callus induction to plant regeneration for HAL2, we noted no apparent differences between FIL2 and HAL2 populations in tissue culture performance. For both populations, the cell suspension cultures

  8. Perennial pastures for marginal farming country in southern Queensland. 2. Potential new grass cultivar evaluation

    Directory of Open Access Journals (Sweden)

    Richard G. Silcock

    2015-01-01

    Full Text Available Trials in the Condamine-Balonne basin, Australia, compared 11 promising perennial pasture grass accessions (4 Bothriochloa, 2 Cenchrus, 2 Urochloa and 1 each of Digitaria, Eragrostis and Panicum species against the best similar commercial cultivars on the basis of ease of establishment from seed, persistence once established, forage yield and ease of seed production.  Accessions sown at a site were determined by prior experience with them on a range of soils.  High quality seed was relatively easy to produce for both Urochloa species and for Eragrostis curvula CPI 30374 but problematic for the Bothriochloa spp.  Once established, all accessions persisted for 3–5 years and most were well grazed, but adequate establishment was sometimes a problem with Panicum stapfianum and Bothriochloa ewartiana.  The dry matter yield ratings of the non-commercial lines were similar to those of the commercial equivalents of the same species.  While agronomically valuable, none of the promising new grasses was considered worthy of commercialization at this point because their strengths did not warrant the setting up of a seed-production business in competition with current commercial enterprises.  Long-standing cultivars such as Gayndah buffel and Nixon sabi grass continued to exhibit their superior pasture qualities.Keywords: Herbicide tolerance, persistence, forage yield, establishment ease, commercialization, seed production.DOI: 10.17138/TGFT(315-26

  9. Determinación de compuestos hidrocarbonados en la pared celular de P. maximum y L. leucocephala en silvopastoreo Determination of hydrocarbonated compounds in the cell wall from P. maximum and L. leucocephala under silvopastoral system conditions

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    Tania Sánchez

    2009-09-01

    Full Text Available Con el objetivo de determinar la concentración de n-alcanos y alcoholes de cadena larga en la pared celular de Panicum maximum cv. Likoni y Leucaena leucocephala cv. Cunningham, se realizó un estudio en una asociación de gramíneas mejoradas y leucaena de 10 años de establecida, la cual ocupa un área de 1,6 ha. Se seleccionaron dichas especies por ser las más representativas en la composición florística. Las muestras se colectaron de enero a diciembre del 2005 y se secaron. La concentración de n-alcanos de cadena impar fue de 167,97 y 222,96 mg/kg de MS y 134,11 y 137,27 mg/kg de MS para guinea y leucaena, en el período poco lluvioso y en el lluvioso, respectivamente. A su vez la concentración de alcoholes de cadena par para la leucaena presentó un valor mayor(2 754,60 y 3 830,18 mg/kg de MS para el período poco lluvioso y lluvioso, respectivamente, que en la guinea (2 571,73-3 679,65 mg/kg de MS para cada período, respectivamente. Se concluye que la concentración de n-alcanos de cadena larga impar fue baja para P. maximum y L. leucocephala en ambos períodos del año; sin embargo, presentaron concentraciones elevadas de alcoholes de cadena larga par, que pudieran ser utilizados como marcadores naturales en las dos especies.With the objective of determining the concentration of n-alkanes and long-chain alcohols in the cell wall of Panicum maximum cv. Likoni and Leucaena leucocephala cv. Cunningham, a study was conducted in an association of improved grasses and leucaena ten years after being established, which occupies an area of 1,6 ha. Such species were selected for being the most representative ones in the floristic composition. The samples were collected from January to December, 2005 and were dried. The concentration of odd-chain n-alkanes was 167,97 and 222,96 mg/kg DM and 134,11 and 137,27 mg/kg DM for Guinea grass and leucaena in the dry and rainy season, respectively. In turn, the concentration of even-chain alcohols for

  10. Basic chromosome numbers and polyploid levels in some South African and Australian grasses (Poaceae

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    J. J. Spies

    1991-10-01

    Full Text Available Chromosome numbers of 46 specimens of grasses, involving 24 taxa from South Africa and Australia, have been determined during the present study. For the first time chromosome numbers are given for Eragrostis sarmentosa (Thunb. Trin. (n = 20. Panicum aequinerve Nees (n = 18,  Digitaria argyrograpta (Nees Stapf (n = 9 and D. maitlandii Stapf & C.E. Hubb. (n = 9. Additional polyploid levels are described for Diplachne fusca (L. Beauv. ex Roem. & Schult. (n = 10 and Digitaria diagonalis (Nees Stapf var.  diagonalis (n = 9. B-chromosomes were observed in several different specimens. The presence of B-chromosomes often results in abnormal chromosomal behaviour during meiosis.

  11. Morphophysiological and chemical aspects of torpedograss (Panicum repens L., Poaceae

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    Simone Meredith Scheffer-Basso

    2007-09-01

    Full Text Available This work evaluated some of the morphophysiological and bromatological aspects of torpedograss (Panicum repens L. through the quantification of accumulation, allocation and chemical composition of dry matter (DM during spring-summer. Four destructive harvests of aerial and underground parts were carried out on 23 October 2003, 3 December 2003, 22 January 2004 and 20 February 2004, corresponding to 31, 73, 123 and 152 days after the start of the spring. In these harvests, the DM accumulation was respectively 1,650; 4,470; 10,900 and 14,540 kg/ha in the aerial part, with leaf percentages between 45% (first harvest and 35% (last harvest. The crude protein (CP, neutral detergent fiber (NDF and acid detergent fiber (ADF changed between the first and the last harvest, from 9.9 to 7% (CP, 63.9% to 70.3% (FDN, and 37% to 40.8% (FDA, in samples composed by leaves, culms, inflorescences and stolons. The DM allocation to rhizomes (Rh, roots (R, leaves (L, culms+stolons (C and inflorescences (I changed, between the first and the last harvest, from 42 to 19% (Rh, 10 to 7% (R, 22 to 27% (L, 25 to 44% (C, and 0 to 2% (I.

  12. Características produtivas, agronômicas e nutricionais do capim-tanzânia em cinco diferentes idades ao corte Productivity, agronomical and nutritional traits of Tanzânia grass cut on five different ages

    Directory of Open Access Journals (Sweden)

    G.H.F. Castro

    2010-06-01

    Full Text Available Avaliou-se o capim-tanzânia (Panicum maximum cv Tanzânia cortado aos 42, 63, 84, 107 e 126 dias quanto à produtividade, às características agronômicas, à composição bromatológica e à digestibilidade in vitro. Observou-se aumento na altura da planta do capim-tanzânia até os 84 dias, com aumento da produção de massa verde de forragem e aumento na produção de matéria seca com o avançar da idade ao corte. O aumento da idade ao corte resultou em diminuição do percentual de folhas e em aumento no percentual de hastes. Na composição bromatológica, observaram-se diminuição do teor de proteína bruta e aumento das frações fibrosas, com aumento do nitrogênio retido nessa última com o avançar da idade. Os resultados obtidos refletiram-se na cinética de fermentação ruminal, descrita pela técnica in vitro semiautomática de produção de gases, demonstrando menor potencial de produção de gases, menor taxa fraccional de fermentação e, consequentemente, menor degradabilidade efetiva da matéria seca. Recomenda-se o corte do capim-tanzânia no intervalo de 42 a 63 dias de crescimento.The potential for use of Tanzania grass (Panicum maximum cv. Tanzania cut at different ages for the production of silage was evaluated. In the first experiment, Tanzania grass, cut at 42, 63, 84, 107, and 126 days of growth, was evaluated considering its productivity, agronomic characteristics and chemical composition. It was observed gain in height of Tanzania grass until the 84th day, with increased the production of green fodder and mass production of dry material with the advancing age of cutting. It also resulted in a decrease in the percentage of leaves and an increase in the percentage of stems. Regarding chemical composition, it was detected a decrease in crude protein percentage and an increase of fibrous fractions with the advancing of age. The results were reflected in the kinetics of rumen fermentation of Tanzania grass cut on the

  13. The effects of energy and protein supplementation strategy and frequency on the performance of beef cattle that grazed on Tanzania grass pastures during the rainy season.

    Science.gov (United States)

    Miorin, R L; Saad, R M; Silva, L D F; Galbeiro, S; Cecato, U; Junior, F L Massaro

    2016-12-01

    The aim of the present study was to evaluate the different supplementation strategies for finishing Nellore beef cattle on pastures of Tanzania guinea grass (Panicum maximum Jacq. 'Tanzania'). The experiment was performed in a 12 ha area divided into 12 paddocks of 1 ha each. Forty-eight, 2-year-old, non-castrated Nellore cattle with an initial body weight (BW) of 384 kg (SEM = 21) were used in this study. The following supplementation strategies were evaluated: (1) mineral supplement supplied once per week (MS), (2) energy and protein supplement with intake regulator (2 g/kg BW) supplied once per week (EPS1), (3) energy and protein supplement (7 g/kg BW) supplied daily (EPS2), and (4) energy and protein supplement (7 g/kg BW) supplied three times per week (EPS3). The average daily gain (ADG) of animals receiving EPS3 was 0.177 kg/day higher than those receiving EPS1 (p supplementation spent more time grazing than the other supplementation groups tested (p supplements, thereby increasing animal performance. Animal performance was higher with increased protein and energy supplementation (7 g/kg BW), independent of the frequency with which supplements were administered.

  14. Producción y calidad del forraje diferido de Panicum coloratum L. en dos periodos de diferimiento y tres momentos de defoliación Production and quality of Panicum coloratum L. deferred forage with two deferred period and three times of defolation

    Directory of Open Access Journals (Sweden)

    M.R. Steinberg

    2012-06-01

    Full Text Available Los sistemas pecuarios de las áreas subtropicales de la Argentina utilizan en invierno forrajes diferidos, provenientes del crecimiento acumulado en verano de gramíneas megatérmicas o pasturas naturales. El objetivo del trabajo fue determinar la producción de materia seca, porcentajes de hojas, tallos, proteína bruta, fibra detergente neutra, fibra detergente ácida, cenizas y digestibilidad del diferido de Panicum coloratum cv Verde. Se evaluaron dos periodos de diferimiento: diferido total (DT, forraje acumulado desde el rebrote en primavera y diferido parcial (DP, forraje acumulado desde un corte a fines de diciembre y ambos con tres oportunidades de defoliación: temprano (mayo; intermedio (julio y tardío (agosto. DT produjo más materia seca, pero con alta proporción de tallos, mayor cantidad de fibra y menor porcentaje de proteínas y cenizas; mientras que DP presentó menos tallos y más hojas y como consecuencia mayor porcentaje de proteínas y cenizas. Se concluye que P. coloratum es un recurso adecuado para diferir, sólo si se lo utiliza con un período corto de diferido y momentos tempranos de uso, ya que presenta un nivel mínimo de proteína suficiente para satisfacer los requerimientos de los animales sin la necesidad de realizar suplementación nitrogenada y valores superiores al 55% de digestibilidad.During winter the livestock production systems in subtropical areas of Argentina use deferred forage of native pasture or warm season grasses from the cumulative growth of the summer. The aim of this study was to determine dry matter production and percentage of leaves, stems, crude protein, neutral detergent fiber, acid detergent fiber, ash and digestibility of deferred forage of Panicum coloratum cv Verde. Two deferred periods were evaluated: total deferred (TD, forage accumulated since the spring regrowth and partial deferred (PD, forage accumulated from a cut in late December, and both with three cut dates: early (May

  15. Yield components and morphogenesis of Aruana grass in response to nitrogen supply Componentes de produção e morfogênese do capim-Aruana em resposta ao nitrogênio

    Directory of Open Access Journals (Sweden)

    José Lavres Jr.

    2004-12-01

    Full Text Available Areas with Aruana grass (Panicum maximum Jacq. in Brazilian pastures, especially those used by sheep, have expanded due to yield and morphological characteristics of this grass that are favorable to these animals. Nevertheless, the knowledge concerning yield attributes of this grass in relation to nitrogen fertilization is very limited. The objective of this research was to evaluate yield and physiological attributes in this forage grass when grown in nutrient solutions containing N rates. The experiment was carried out in a greenhouse with plastic pots containing ground quartz as substrate, during the Spring season. Six N rates in the solution (14, 112, 210, 294, 378, and 462 mg L-1, with 70% N-NO3- and 30% N-NH4+ were tested. Experimental units were set up in a completely randomized block design, with four replications. Plants were harvested at 35 days after the seedlings were transplanted to the pots and again at 28 days after the first harvest. After the second harvest, the roots were taken from the substrate. In both growing periods, dry matter yield for plant tops and roots, leaf area, number of expanded green leaves, number of tillers, leaf appearance rate, and phyllochron were significantly affected by the N rates, and the data were adjusted to a second-order model. Aruana grass required high rates of N to show maximum response in those variables.No Brasil, as áreas de pastagens formadas com o capim-Aruana (Panicum maximum Jacq., particularmente destinadas ao pastejo por ovinos, têm crescido devido às características produtivas e estruturais da gramínea, propícias à exploração destes rebanhos. Porém, o conhecimento do comportamento produtivo do capim-Aruana relacionado à adubação nitrogenada é escasso. Avaliaram-se atributos produtivos e fisiológicos desta gramínea forrageira, quando submetida a doses de N em solução nutritiva. O experimento foi conduzido em casa-de-vegetação, utilizando vasos contendo sílica como

  16. Efeitos da compactação, da inclusão de aditivo absorvente e do emurchecimento na composição bromatológica de silagens de capim-tanzânia Effects of different compaction degrees, inclusion of absorbent additive and wilting on the chemical composition of tanzania grass silages

    Directory of Open Access Journals (Sweden)

    Valdir Botega Tavares

    2009-01-01

    Full Text Available Objetivou-se neste trabalho avaliar o efeito do grau de compactação, da inclusão de aditivo absorvente e do emurchecimento da forragem na composição bromatológica de silagens de capim-tanzânia. O capim-tanzânia (Panicum maximum Jacq. cv. Tanzânia I foi colhido aos 60-65 dias de crescimento e ensilado em silos experimentais de PVC adaptados com válvula tipo Bunsen, com capacidade individual de 8,5 kg. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições, em esquema fatorial 3 × 5, composto de três tipos de silagens (testemunha, com 5% de polpa cítrica e com capim pré-emurchecido e cinco graus de compactação (400, 500, 600, 700 ou 900 kg/m³. O aumento da densidade reduziu o pH e o N-amoniacal, de modo que, em maiores densidades, o pH se manteve na faixa ideal. A inclusão de polpa cítrica e o pré-emurchecimento do capim reduziram as perdas por efluente e gás das silagens. Com o aumento da densidade, a quantidade de efluente aumentou na silagem testemunha e diminuiu nas silagens com polpa cítrica.The objective of this work was to evaluate the effects of different compaction degrees, inclusion of absorbent additive and wilting on the chemical composition of tanzania grass silages. The experiment was conducted using tanzania grass (Panicum maximum Jacq. cv. Tanzânia I harvested at 60-65 days of growth. The forage was ensiled in experimental PVC silos fitted with Bunsen type valves, with capacity for about 4 and 8 kg each. The treatments consisted of three types of silages (control, 5% of citric pulp and pre-wilted with five compaction degrees (400, 500, 600, 700 and 900 kg/m³. The experimental design was random blocks, with four replicates. Citric pulp and pre-wilting increased the dry matter content of tanzania grass silages. The increased density resulted into decreases in the pH values and amoniacal-N contents; the greatest densities resulted in pH values within the ideal range. The presence

  17. Panicum simulans (Paniceae, Poaceae, a new species from southern Africa and its leaf anatomy

    Directory of Open Access Journals (Sweden)

    L. Smook

    1993-10-01

    Full Text Available Panicum simulans Smook from northern Namibia is formally described. The morphology and leaf blade anatomy in transection and surface view, as observed under the light microscope, are described. The species is compared to others with which it has been confused in the past.  P. simulans can be readily distinguished from  P. novemnerve Stapf and P schinzii Hack, on the basis of both anatomical and morphological characters such as the venation of the lower glume and the photosynthetic anatomy, which is of the NAD-me subtype of the C4 photosynthetic pathway. On this basis it appears that P simulans is closely allied to the P. coloratum L. group of species and should be placed in section Panicum of subgenus Panicum.

  18. resistance of napier grass clones to napier grass stunt disease

    African Journals Online (AJOL)

    ACSS

    Napier grass (Pennisetum purpureum Schumach) is the major livestock fodder under intensive and semi-intensive systems in East Africa. However, the productivity of the grass is constrained by Napier grass Stunt Disease. (NSD). The purpose of this study was to identify Napier grass clones with resistance to NSD.

  19. Resistance of Napier grass clones to Napier grass Stunt Disease ...

    African Journals Online (AJOL)

    Napier grass (Pennisetum purpureum Schumach) is the major livestock fodder under intensive and semi-intensive systems in East Africa. However, the productivity of the grass is constrained by Napier grass Stunt Disease (NSD). The purpose of this study was to identify Napier grass clones with resistance to NSD.

  20. Influence of leguminous and non-leguminous woody plants on the ...

    African Journals Online (AJOL)

    Keywords: associations; biomass; canopy; competition; digitaria eriantha; eragrostis lehmanniana; grass biomass; grasses; herbaceous layer; mixed bushveld; nutrients; panicum maximum; preference; schmidtia pappophoroides; soil enrichment; subhabitats; tree competitiveness; tree density; trees; woody plants

  1. Evaluation of nutritive value of water hyacinth ( Eichhornia Crassipes )

    African Journals Online (AJOL)

    Panicum maximum) mixture as animal feed resources in the tropics were evaluated. The mixture of the treatments: A (0% water hyacinth + 90% Guinea grass + 10% concentrate), B (30% water hyacinth + 60% Guinea grass + 10% concentrate), ...

  2. CULTIVARES DE MILHO E DE GRAMÍNEAS FORRAGEIRAS SOB MONOCULTIVO E CONSORCIAÇÃO MAIZE AND FORAGE GRASS CULTIVARS UNDER MONOCROPPING AND INTERCROPPING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lindomar Pereira Simões

    2010-10-01

    -weight: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="JUSTIFY">The purpose of this study was to evaluate the performance of maize and forage grass (Brachiaria brizantha and Panicum maximum cultivars under monocropping and intercropping systems. The experiment was carried out in randomized complete blocks, in a 3x4 + 7 factorial design, with four replications. The first factor consisted of three maize cultivars (AL Bandeirantes, an open pollination variety; AG 2040, a double cross; and Pioneer 30F87, a triple cross and the second one included four forage cultivars (Marandu and Xaraés, from B. brizantha, and Tanzânia and Mombaça, from P. maximum. The seven additional treatments consisted of the respective tested cultivars monocroppings. Maize and forage grasses were sown simultaneously, the first in rows, spaced 1.0 m apart, and the second by throwing. Hybrid Pioneer 30F87 maize yields were the highest ones, for both monocropping and intercropping systems, and maize affected dry weight gain of forages, when compared to the monocropping system. For intercropping, P. maximum forage cultivars were the most productive ones, while, for monocropping, the Mombaça cultivar presented the highest dry matter production level.

    KEY-WORDS: Zea mays; Brachiaria brizantha; Panicum maximum; agriculture and livestock integration; pasture.

  3. Retenção do fósforo de fenos de gramíneas tropicais em ovinos Phosphorus balance in sheep fed on tropical grass hays

    Directory of Open Access Journals (Sweden)

    R.A. Reis

    1999-06-01

    Full Text Available Mediu-se a retenção do fósforo de quatro gramíneas tropicais, capim-gordura (Melinis minutiflora, capim-braquiária (Brachiaria decumbens, capim-coastcross (Cynodon dactilon e capim-colonião (Panicum maximum, em cinco ovinos por meio de ensaios de balanço de fósforo. O experimento constou de quatro fases, cada uma com duração de 21 dias (14 dias de adaptação à dieta e sete dias de colheita de fezes, totalizando 20 observações. A análise dos dados foi feita por polinômios ortogonais, testando-se os efeitos de tratamento, de período e de animal, e os contrastes foram comparados pelo teste F. A retenção de fósforo foi negativa nos fenos dos capins gordura, braquiária e coastcross e positiva no feno do capim-colonião. Por análise de regressão, a perda fecal do fósforo endógeno foi estimada em 15,5mg/kg PV/dia e o coeficiente médio de retenção foi de 0,37. Pela razão entre o balanço e a ingestão, estimou-se que o consumo de fósforo necessário para alcançar o equilíbrio foi de 44mg/kg PV/dia.One experiment was conducted using five adult sheep fed on four tropical grass hays to determine phosphorus (P retention. The experiment consisted of four periods of 21 days (14 days adaptation and seven days faeces collection. The treatments were: A molasses grass (Melinis minutiflora, B brachiaria grass (Brachiaria decumbens, C coastcross grass (Cynodon dactilon and D Guinea grass (Panicum maximum. Phosphorus concentrations were 0.05%, 0.07%, 0.11% and 0.18% for treatments A, B, C and D, respectively. The effects of treatment, period and animal were evaluated by ortogonal polynomials and the contrasts by F test. Negative P balances were produced in treatments A, B and C (-13.05, -9.36 and -8.26mg/kg LW/day, respectively which were not significantly different from each other. Positive P balance of 8.14mg/kg LW/day was produced in treatment D, which was significantly higher (P<0.05 than treatments A, B and C. Endogenous losses

  4. GRASS GIS Vector Processing: Towards GRASS 7

    Science.gov (United States)

    Metz, Markus; Landa, Martin; Petrasova, Anna; Petras, Vaclav; Chemin, Yann; Neteler, Markus

    2014-05-01

    The upcoming GRASS GIS 7 release improves not only raster processing and general design but the vector processing in the first place. GRASS GIS, as a topological GIS, recognizes that the topology plays the key role in the vector processing and analysis. Topology ensures that adjacent geographic components in a single vector map are related. In contrast to non-topological GIS, a border common to two areas exists only once and is shared between the two areas. Topological representation of vector data helps to produce and maintain vector maps with clean geometry as well as enables the user to perform certain analyses that can not be conducted with non-topological or spaghetti data. Non-topological vector data are automatically converted to a topological representation upon import. Further more, various cleaning tools exist to remove non-trivial topological errors. In the upcoming GRASS GIS 7 release the vector library was particularly improved to make it faster and more efficient with an improved internal vector file format. This new topological format reduces memory and disk space requirements, leading to a generally faster processing. Opening an existing vector requires less memory providing additionally support for large files. The new spatial index performs queries faster (compared to GRASS GIS 6 more than 10 times for large vectors). As a new option the user can select a file-based version of the spatial index for large vector data. All topological cleaning tools have been optimized with regard to processing speed, robustness, and system requirements. The topological engine comes with a new prototype for direct read/write support of Simple Features API/OGR. Additionally vector data can be directly exchanged with topological PostGIS 2 databases. Considering the wide spread usage of ESRI Shapefile, a non-topological format for vector data exchange, it is particularly advantageous that GRASS GIS 7 offers advanced cleaning tools. For power users and programmers, the

  5. A novel triculture system (CC3 for simultaneous enzyme production and hydrolysis of common grasses through submerged fermentation

    Directory of Open Access Journals (Sweden)

    Vincent Vineeth Leo

    2016-03-01

    Full Text Available The perennial grasses are considered as a rich source of lignocellulosic biomass, making it a second generation alternative energy source and can diminish the use of fossil fuels. In this work, four perennial grasses Saccharum arundinaceum, Panicum antidotale, Thysanolaena latifolia and Neyraudia reynaudiana were selected to verify their potential as a substrate to produce hydrolytic enzymes and to evaluate them as second generation energy biomass. Here, cellulase and hemi-cellulase producing three endophytic bacteria (Burkholderia cepacia BPS-GB3, Alcaligenes faecalis BPS-GB5 and Enterobacter hormaechei BPS-GB8 recovered from N. reynaudiana and S. arundinaceum were selected to develop a triculture (CC3 consortium. During 12 days of submerged cultivation, a 55-70% loss in dry weight was observed and the maximum activity of β-glucosidase (5.36 to 12.34 IU and Xylanase (4.33 to 10.91 IU were observed on 2nd and 6th day respectively, whereas FPase (0.26 to 0.53 IU and CMCase (2.31 to 4.65 IU showed maximum activity on 4th day. Around 15-30% more enzyme activity was produced in CC3 as compared to monoculture (CC1 and coculture (CC2 treatments, suggested synergetic interaction among the selected three bacterial strains. Further, the biomass was assessed using Fourier-transform infrared spectroscopy (FTIR and Scanning electron microscopy (SEM. The FTIR analysis provides important insights into the reduction of cellulose and hemicellulose moieties in CC3 treated biomass and SEM studies shed light into the disruption of surface structure leading to access of cellulose or hemicelluloses microtubules. The hydrolytic potential of the CC3 system was further enhanced due to reduction in lignin as evidenced by 1-4% lignin reduction in biomass compositional analysis. Additionally, laccase gene was detected from A. faecalis and E. hormaechei which further shows the laccase production potential of the isolates. To our knowledge, first time we develop an

  6. Genome-size variation in switchgrass (Panicum virgatum): flow cytometry and cytology reveal rampant aneuploidy

    Science.gov (United States)

    Switchgrass (Panicum virgatum L.), a native perennial dominant of the prairies of North America, has been targeted as a model herbaceous species for biofeedstock development. A flow-cytometric survey of a core set of 11 primarily upland polyploid switchgrass accessions indicated that there was con...

  7. Evaluation of parameters affecting switchgrass tissue culture: toward a consolidated procedure forAgrobacterium-mediated transformation of switchgrass (Panicum virgatum).

    Science.gov (United States)

    Lin, Chien-Yuan; Donohoe, Bryon S; Ahuja, Neha; Garrity, Deborah M; Qu, Rongda; Tucker, Melvin P; Himmel, Michael E; Wei, Hui

    2017-01-01

    Switchgrass ( Panicum virgatum ), a robust perennial C4-type grass, has been evaluated and designated as a model bioenergy crop by the U.S. DOE and USDA. Conventional breeding of switchgrass biomass is difficult because it displays self-incompatible hindrance. Therefore, direct genetic modifications of switchgrass have been considered the more effective approach to tailor switchgrass with traits of interest. Successful transformations have demonstrated increased biomass yields, reduction in the recalcitrance of cell walls and enhanced saccharification efficiency. Several tissue culture protocols have been previously described to produce transgenic switchgrass lines using different nutrient-based media, co-cultivation approaches, and antibiotic strengths for selection. After evaluating the published protocols, we consolidated these approaches and optimized the process to develop a more efficient protocol for producing transgenic switchgrass. First, seed sterilization was optimized, which led to a 20% increase in yield of induced calluses. Second, we have selected a N 6 macronutrient/B 5 micronutrient (NB)-based medium for callus induction from mature seeds of the Alamo cultivar, and chose a Murashige and Skoog-based medium to regenerate both Type I and Type II calluses. Third, Agrobacterium -mediated transformation was adopted that resulted in 50-100% positive regenerated transformants after three rounds (2 weeks/round) of selection with antibiotic. Genomic DNA PCR, RT-PCR, Southern blot, visualization of the red fluorescent protein and histochemical β-glucuronidase (GUS) staining were conducted to confirm the positive switchgrass transformants. The optimized methods developed here provide an improved strategy to promote the production and selection of callus and generation of transgenic switchgrass lines. The process for switchgrass transformation has been evaluated and consolidated to devise an improved approach for transgenic switchgrass production. With the

  8. EFEITO DA ADUBAÇÃO SILICATADA SOBRE GRAMÍNEAS FORRAGEIRAS E CARACTERÍSTICAS QUÍMICAS DO SOLO EFFECT OF SILICON FERTILIZER ON FORAGE GRASSES AND SOIL CHEMICAL CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Rogério Soares de Freitas

    2010-05-01

    .

    This research assessed the effect of calcium silicate application to soil surface on dry matter production and Si concentration on grass shoots, as well as chemical characteristics of a soil under degraded forage grass pasture. The experiment was carried out in a greenhouse, using a completely randomized design, in a 5x2 factorial arrangement, with four replicates. Treatments consisted of five calcium silicate doses (0 kg ha-1; 500 kg ha-1; 1,000 kg ha-1; 1,500 kg ha-1; and 2,000 kg ha-1 and two forage grasses (Brachiaria brizantha cv. Marandu and Panicum maximum cv. Mombaça. Shoot cuttings were performed at 45 and 95 days after sowing. Shoot dry mass accumulation and absorbed Si foliar concentrations were quantified, besides soil pH, Ca, P, Al, and V values, after grass harvesting. Calcium silicate application induced higher absorption of Si in Marandu, as well as in Mombaça. Marandu cultivar dry mass accumulation did not differ from Mombaça. Calcium silicate application increased pH and soil base saturation decreased the aluminum level.

    KEY-WORDS: Brachiaria brizantha; Panicum maximum; silicon; acidity correction.

  9. Milk yield and composition, feed intake and stocking rate of crossbread cows in tropical grasses managed in a rotational grazing system Produção e composição do leite, consumo de matéria seca e taxa de lotação em pastagens de gramíneas tropicais manejadas sob lotação rotacionada

    Directory of Open Access Journals (Sweden)

    Nelson Massaru Fukumoto

    2010-07-01

    Full Text Available The objective of this study was to evaluate milk yield and composition, dry matter intake, and stocking rate in pastures with tanzania grass (Panicum maximum cv. Tanzânia, star grass (Cynodon nlemfuensis cv. Estrela-Africana, and marandu grass (Brachiaria brizantha cv. Marandu. The grasses were managed in a rotational grazing system with Holstein x Zebu crossbreed cows, with a 30-day resting period and three days of paddock occupation. The pastures were fertilized with 1,000 kg/ha/year using the 20:05:20 (NPK formula, split in three applications during the rainy season. It was used a complete random block experimental design with three factors being studied and two replications. In the experiment, four cows/paddock were used and, when it was necessary, regulator animals were added in order to obtain a supply of 7% body weight green forage dry matter. The animals were individually fed concentrate at 2 kg/day during the experimental period. Milk yield did not differ among the three grasses, with values of 9.1; 9.1; and 8.7 kg/cow/day for pastures with tanzania grass, star grass and marandu grass, respectively. Similarly, grass did not affect milk chemical composition. Stocking rate was similar among the three grasses, with values of 4.6; 4.5 and 5.0 UA/ha for tanzania grass, star grass and marandu grass, respectively. The highest dry matter intake was observed for tanzania grass with 2.6% of the body weight while stargrass (2.3% and marandu grass (2.4% did not differ among each other. The highest dry matter intake on tanzania grass pasture was not reflected on milk yield per animal. Milk yield and composition and stocking rate are similar among the evaluated grasses.Objetivou-se com este trabalho avaliar a produção e composição química do leite, o consumo de matéria seca e a taxa de lotação em pastagens de capim-tanzânia (Panicum maximum Jacq. cv. Tanzânia, grama-estrela (Cynodon nlemfuensis Vanderyst cv. Estrela-Africana e capim

  10. Accumulation of 137Cs and 90Sr from contaminated soil by three grass species inoculated with mycorrhizal fungi

    International Nuclear Information System (INIS)

    Entry, J.A.; Watrud, L.S.; Reeves, M.

    1999-01-01

    The use of plants to accumulate low level radioactive waste from soil, followed by incineration of plant material to concentrate radionuclides may prove to be a viable and economical method of remediating contaminated areas. We tested the influence of arbuscular mycorrhizae on 137 Cs and 90 Sr uptake by bahia grass (Paspalum notatum), johnson grass (Sorghum halpense) and switchgrass (Panicum virginatum) for the effectiveness on three different contaminated soil types. Exposure to 137 Cs or 90 Sr over the course of the experiment did not affect above ground biomass of the three grasses. The above ground biomass of bahia, johnson and switchgrass plants accumulated from 26.3 to 71.7% of the total amount of the 137 Cs and from 23.8 to 88.7% of the total amount of the 90 Sr added to the soil after three harvests. In each of the three grass species tested, plants inoculated with Glomus mosseae or Glomus intraradices had greater aboveground plant biomass, higher concentrations of 137 Cs or 90 Sr in plant tissue, % accumulation of 137 Cs or 90 Sr from soil and plant bioconcentration ratios at each harvest than those that did not receive mycorrhizal inoculation. Johnson grass had greater aboveground plant biomass, greater accumulation of 137 Cs or 90 Sr from soil and plant higher bioconcentration ratios with arbuscular mycorrhizal fungi than bahia grass and switchgrass. The greatest accumulation of 137 Cs and 90 Sr was observed in johnson grass inoculated with G. mosseae. Grasses can grow in wide geographical ranges that include a broad variety of edaphic conditions. The highly efficient removal of these radionuclides by these grass species after inoculation with arbuscular mycorrhizae supports the concept that remediation of radionuclide contaminated soils using mycorrhizal plants may present a viable strategy to remediate and reclaim sites contaminated with radionuclides

  11. GUI development for GRASS GIS

    Directory of Open Access Journals (Sweden)

    Martin Landa

    2007-12-01

    Full Text Available This article discusses GUI development for GRASS GIS. Sophisticated native GUI for GRASS is one of the key points (besides the new 2D/3D raster library, vector architecture improvements, etc. for the future development of GRASS. In 2006 the GRASS development team decided to start working on the new generation of GUI instead of improving the current GUI based on Tcl/Tk.

  12. Microbial population and nutritional compounds in the organs of tanzania-grass before and after ensilage/Populações microbianas e componentes nutricionais nos órgãos do capim-tanzânia antes e após a ensilagem

    Directory of Open Access Journals (Sweden)

    Daniele de Jesus Ferreira

    2007-07-01

    Full Text Available This experiment was carried with the objective of evaluating the microbial populations and the nutritional value of different organs of plants of the tanzânia-grass (Panicum maximum before and after the ensilage. Ten samples were collected at random at the pasture with the use of a square of 1 m2, were taken the botanical separation of the leaves in expansion, expanded leaves, leaves senesce, stem and the plant. Counting of microorganisms and the nutritional value were made in the different organs of the plant. Was determined the number of lactic bacterium, enterobacterium, fungi and yeasts and dry matter values, crude protein, neutral detergent fiber, acid detergent fiber and hemicellulose. The microbial populations were variable in function of the organ of the plant, and the stem is the organ that assures the growth of lactic bacteria and inhibition of growth of undesirable microorganisms during the ensilage of the tanzânia- grass. In the nutritional extent, a decreasing hierarchy of the value bromatológic exists: leafs in expansion, expanded leaf, plant completes and stem before and after the ensilage process.Este experimento foi conduzido com o objetivo de avaliar as populações microbianas e o valor nutricionaldos diferentes órgãos das plantas do capim-tanzânia (Panicum maximum antes e após a ensilagem. Foram coletadas dez amostras do pasto, ao acaso com o uso de um quadrado de 1 m2. Foram feitos as separações botânica das folhas em expansão, folhas expandidas, folhas senescente, colmo e a planta inteira. Foram efetuadas contagens de microrganismos e o valor nutricional dos diferentes órgãos da planta. Determinou-se o número de bactérias láticas, enterobactérias, fungos e leveduras e os valores de matéria seca, proteína bruta, fibra em detergente neutro, fibra em detergente ácido e hemicelulose. As populações microbianas foram variáveis em função do órgão da planta, e o colmo foi o órgão que assegurou o

  13. Metagenomics at Grass Roots

    Indian Academy of Sciences (India)

    tostabilize metal-contaminated soils, and sequester toxic metals. Identification of rhizospheric microbial communities that toler- ate contaminants and promote transformations that render the soil less toxic, are invaluable for phytoremediation and restoration of degraded lands. An Example of Bacterial Communities in Grass ...

  14. Metagenomics at Grass Roots

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 22; Issue 3. Metagenomics at Grass Roots. Sudeshna ... benefit human health, agriculture, and ecosystemfunctions. This article provides a brief history of technicaladvances in metagenomics, including DNA sequencing methods,and some case studies.

  15. Ecological aspects study of replacement intercropping patterns of Soybean (Glycine max L. and Millet (Panicum miliaceum L.

    Directory of Open Access Journals (Sweden)

    Goudarz Ahmadvand

    2016-03-01

    Full Text Available Intercropping is considered for increasing and stability of yield in per unit. In order to study the effects of soybean (Glycine max L. and millet (Panicum miliaceum L. replacement intercropping on agronomic traits, diversity of weeds and soil biological activity, an experiment was conducted at the Research Station of Agricultural Faculty, of Bu-Ali Sina University, in 2014. The experiment was carried out as a randomized complete block design with three replications. The replacement intercropping series consisted of monoculture of soybean, monoculture of millet, 75% soybean+ 25% millet, 50% soybean+ 50% millet and 25% soybean+ 75% millet. The results showed that the highest seed yield of 219.8 and 171.9 gm-2 belonged to monoculture of soybean and monoculture of millet, respectively. Intercropping reduced maximum leaf area index of soybean and millet but leaf chlorophyll content of soybean and millet were increased. The highest number of pods per plant, number of seeds per plant in soybean and panicle number per plant in millet were obtained in 50S:50M ratio. Mean soil respiration rate in intercropping treatments was 4 and 8 % higher than the monoculture of soybean and millet, respectively. Intercropping patterns of 50S:50M and 25S:75M were successful in reducing weed plant density and diversity in comparison with soybean monoculture. Results showed that in all intercropping treatments, land equivalent ratio was more than one. Maximum value of land equivalent ratio (2.20 was achieved in 50S:50M treatment. Soybean and millet intercropping at different levels of replacement, didn’t have actual yield loss. Calculating the aggressivity showed that millet was more dominate than soybean. The maximum relative crowding coefficient of soybean was observed in 75S:25M, however that of millet was obtained in 25S:75M and 50S:50M intercroppings indicating that millet is more competitor than soybean.

  16. Diuretic activity of ethanolic extract of Panicum repens L. roots and rhizomes.

    Science.gov (United States)

    Hozaien, Hoda E; El-Tantawy, Walid Hamdy; Temraz, Abeer; El-Gindi, Omayma D; Taha, Kamilia F

    2018-02-08

    The diuretic activity of ethanolic extract of Panicum repens was investigated in rats. A single oral dose of 500 mg/kg of P. repens extract were given to rats, after 24 h, urine volume, its sodium and potassium concentrations were estimated. Treatment with P. repens extract caused a significant increase in tested parameters as compared to their corresponding controls, p < 0.05.

  17. Capim-tanzânia submetido a combinações entre intensidade e freqüência de pastejo Tanzânia grass subjected to combinations of intensity and frequency of grazing

    Directory of Open Access Journals (Sweden)

    Rodrigo Amorim Barbosa

    2007-03-01

    Full Text Available O objetivo deste trabalho foi avaliar as características estruturais e a produção de forragem do capim-tanzânia (Panicum maximum Jacq. cv. Tanzânia sob condições de pastejo rotativo, em um Latossolo Vermelho distrófico, num experimento realizado em Campo Grande, MS. Os tratamentos corresponderam a combinações entre três condições de pré e duas condições de pós-pastejo, e foram alocados às unidades experimentais segundo um delineamento de blocos completos casualizados, com três repetições e arranjo fatorial 3x2. As condições de pré-pastejo de 90, 95 e 100% de interceptação de luz (IL foram atingidas consistentemente com alturas de dossel em torno de 60, 70 e 85 cm, respectivamente. Pastejos iniciados com 90% de IL resultaram em maior número de ciclos de pastejo em relação aos iniciados com 95 e 100% de IL. O acúmulo de forragem foi maior em pastejos realizados com 95% do que com 90 ou 100% de IL, mas não houve diferença entre os tratamentos de 90 e 95% de IL para acúmulo de folhas. O acúmulo de colmos aumentou após os 95% de IL, indicando a importância da freqüência de pastejo como maneira de controlar a estrutura e a composição do dossel.The objective of this work was to evaluate the structural characteristics and herbage accumulation of Tanzania grass pastures (Panicum maximum cv. Tanzania under rotationally grazing, in an Oxisol, in experiment carried out at Campo Grande, MS. Treatments corresponded to combinations of three pre and two post-grazing conditions, and were allocated to experimental units according to a complete randomized block design, with three replications and a 3x2 factorial arrangement. The pre-grazing conditions of 90, 95 and 100% light interception (LI were achieved consistently with swards heights around 60, 70 and 85 cm, respectively. Grazings at 90% LI resulted in larger number of grazing cycles than grazings at 95 and 100% LI. Total herbage accumulation was larger with grazings at

  18. Produtividade e composição química de gramíneas tropicais na Zona da Mata de Pernambuco Productivity and chemical composition of tropical grasses in the Forest Zone of Pernambuco

    Directory of Open Access Journals (Sweden)

    Mércia Virginia Ferreira dos Santos

    2003-08-01

    Full Text Available O trabalho foi realizado com o objetivo de avaliar o potencial produtivo e a composição química de cinco gramíneas tropicais (Pennisetum purpureum Schum. cv. Pioneiro, P. purpureum Schum cv. Mott; Panicum maximum Jacq. cv. Mombaça, P. maximum Jacq cv. Tanzânia e Brachiaria brizantha (Hochst Stapf. cv. Marandu. Os cortes foram realizados em intervalos de 35 dias e a 40 cm do solo. O cultivar Pioneiro apresentou maior produção de MS (7,35 t/ha/35 dias, quando comparado aos cultivares Mott (5,28 t/ha/35 dias e Tanzânia (5,23 t/ha/35 dias, não diferindo dos demais. Brachiaria brizantha apresentou maior número de perfilhos totais (538,72/m², entretanto o peso dos perfilhos axilares foi inferior ao dos demais cultivares. Os cultivares de P. purpureum apresentaram maior perfilhamento axilar e menor perfilhamento basal, quando comparados aos cultivares de P. maximum. Os teores de PB variaram de 6,96 a 10,2%, tendo o cultivar Pioneiro apresentado o maior valor. As análises de FDN e FDA não evidenciaram diferenças entre as forrageiras avaliadas, obtendo-se valores médios de 73,83 e 39,20%, respectivamente. No intervalo de corte avaliado, as forrageiras apresentaram elevada proporção de folhas (> 80%, mostrando potencial para utilização em explorações pecuárias na Zona da Mata de Pernambuco.This work was carried out to evaluate the productive potencial and chemical composition of five grasses (Pennisetum purpureum Schum. cv. Pioneiro, P. purpureum Schum cv. Mott; Panicum maximum Jacq. cv. Mombaça, P. maximum Jacq cv. Tanzânia, e Brachiaria brizantha (Hochst Stapf. cv. Marandu. The cuts were performed at 35 days of intervals and 40 cm above ground. Pioneiro showed higher DM yield (7.35 t DM/ha/35 days when compared to the Dwarf Elephantgrass (5.28 t DM/ha/35 days and Tanzânia grass (5.23 t DM/ha/35 days, being similar to the others. Brachiaria brizantha presented the highest total tillering (538.72/m² however the aerial tiller

  19. Desempenho de seis gramíneas solteiras ou consorciadas com o Stylosanthes guianensis cv. Mineirão e eucalipto em sistema silvipastoril Performance of six tropical grasses alone or associated with Stylosanthes guianensis cv. Mineirão and eucalypt in silvopastoral system

    Directory of Open Access Journals (Sweden)

    Carlos Mauricio Soares de Andrade

    2003-12-01

    Full Text Available Conduziu-se este estudo na região dos Cerrados de Minas Gerais, visando avaliar o desempenho de seis gramíneas forrageiras (Brachiaria brizantha cv. Marandu, B. brizantha cv. MG-4, B. decumbens cv. Basilisk, Panicum maximum cv. Mombaça, Melinis minutiflora e Hyparrhenia rufa, consorciadas ou não com a leguminosa Stylosanthes guianensis cv. Mineirão e Eucalyptus sp., em um sistema silvipastoril. As forrageiras foram estabelecidas em parcelas medindo 12 x 10 m, nas entrelinhas do eucalipto, em um delineamento experimental de blocos ao acaso, com três repetições, e avaliadas quanto ao grau de cobertura do solo, % de leguminosa e disponibilidade de matéria seca total no sub-bosque, um ano após o estabelecimento, submetidas a pastejos de curta duração. Após dois ciclos de pastejo, houve redução da proporção da leguminosa no consórcio com todas as gramíneas, sendo mais evidente com as mais agressivas (B. brizantha cv. Marandu e B. decumbens, onde ela quase desapareceu. Entretanto, a presença do estilosantes Mineirão favoreceu a produtividade do sub-bosque, quando consorciado com as demais gramíneas. O melhor desempenho produtivo foi obtido pelas gramíneas B. brizantha cv. Marandu, B. decumbens e P. maximum cv. Mombaça; a última principalmente quando consorciada com o estilosantes Mineirão.A study was conducted in the Brazilian Cerrados to evaluate the performance of six tropical forage grasses (Brachiaria brizantha cv. Marandu, B. brizantha cv. MG-4, B. decumbens cv. Basilisk, Panicum maximum cv. Mombaça, Melinis minutiflora and Hyparrhenia rufa, associated or not with the tropical forage legume Stylosanthes guianensis cv. Mineirão, in a silvopastoral system with a clone of Eucalyptus sp. The forages were established in plots of 12 x 10 m, in the interrows of eucalypts, in a randomized block design with three replications. Ground cover, proportion of the legume and total dry matter availability in the understorey were

  20. Comparative feedstock analysis in Setaria viridis L. as a model for C4 bioenergy grasses and Panicoid crop species

    Directory of Open Access Journals (Sweden)

    Carloalberto ePetti

    2013-06-01

    Full Text Available Second generation feedstocks for bioethanol will likely include a sizable proportion of perennial C4 grasses, principally in the Panicoideae clade. The Panicoideae contain agronomically important annual grasses including Zea mays L. (maize, Sorghum bicolor (L. Moench (sorghum, and Saccharum officinarum L. (sugar cane as well as promising second generation perennial feedstocks including Miscanthus x giganteus and Panicum virgatum L. (switchgrass. The underlying complexity of these polyploid grass genomes is a major limitation for their direct manipulation and thus driving a need for rapidly cycling comparative model. Setaria viridis (green millet is a rapid cycling C4 Panicoid grass with a relatively small and sequenced diploid genome and abundant seed production. Stable, transient and protoplast transformation technologies have also been developed for S. viridis making it a potentially excellent model for other C4 bioenergy grasses. Here, the lignocellulosic feedstock composition, cellulose biosynthesis inhibitor (CBI response and saccharification dynamics of S. viridis are compared with the annual s00orghum and maize and the perennial switchgrass bioenergy crops as a baseline study into the applicability for translational research. A genome-wide systematic investigation of the cellulose synthase-A (CesA genes was performed identifying eight candidate sequences. Two-developmental stages; a metabolically active young tissue and b metabolically plateaued (mature material are examined to compare biomass performance metrics.

  1. Alfalfa (Medicago sativa L. overseeding on mature switchgrass (Panicum virgatum L. stand: biomass yield and nutritive value after the establishment year

    Directory of Open Access Journals (Sweden)

    Alberto Mantino

    2016-08-01

    Full Text Available Perennial crops can positively act on the environment providing a better inter-annual protection of soil cover from water erosion, limiting soil fertility degradation, the risk of nutrient leaching and the exploitation of water for irrigation. Switchgrass (Panicum virgatum L., a warm-season grass native from North America, has been cultivated for decades as forage crop and only recently as bioenergy crop. Even if several studies reported a positive effect of nitrogen (N supply on switchgrass yield and quality, potential indirect and direct environmental risks (e.g., eutrophication and greenhouse gas emission are related to this practice. For this reason grass-legume intercropping can represent a sustainable practice able to increase biomass yield and quality, and at the same time to improve N use efficiency, soil structure and fertility. Based on this, the aim of this study was to evaluate the suitability of switchgrass to Mediterranean environment as forage crop and to improve biomass yield and its nutritional value by intercropping with alfalfa (Medicago sativa L. During spring 2013, in two switchgrass pure stands (varieties Alamo and Blackwell, respectively, alfalfa was established through direct seeding implementing a split-plot experimental design. Our first year results report a positive effect of the intercropping in increasing the total annual yield of the stand, of about 20% with respect to the pure switchgrass stand. However, the presence of alfalfa negatively affected switchgrass yield in the mixture. In both varieties, the crude protein content was higher in the mixture than in the pure switchgrass stands. Conversely, the neutral detergent fibre content in the mixture was lower than in pure switchgrass. Then, our results show that switchgrass-alfalfa intercropping leads to increase the profitability of grassland-based livestock production.

  2. Greenhouse gas flux under warm-season perennial C4 grasses across different soil and climate gradients on the Islands of Hawaii

    Science.gov (United States)

    Pawlowski, M. N.; Crow, S. E.; Sumiyoshi, Y.; Wells, J.; Kikkawa, H. R.

    2011-12-01

    Agricultural soils can serve as either a sink or a source for atmospheric carbon (C) and other greenhouse gases (GHG). This is particularly true for tropical soils where influences from climate and soil gradients are wide ranging. Current estimates of GHG flux from soil are often under or overestimated due to high variability in sample sites and inconsistencies in land use and vegetation type, making extrapolation to new study systems difficult. This work aimed to identify patterns of trace fluxes of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) across two soil types and three species of warm season perennial C4 grasses: Pennisetum purpureum (Napier grass), Panicum maximum (Guinea grass) and Saccharum officinarum (sugar cane) on the islands of Oahu and Maui in Hawaii. Multiple static vented chambers were installed into replicate plots for each species; flux measurements were made during the growth, fertilization and harvest cycles at set time intervals for one hour and analyzed by gas chromatography. Initial results from Oahu indicate no significant differences in CO2 flux between the P. maximum and P. purpureum species after fertilization or at full growth. We observed an average flux of 143 mg m-2 h-1 and 155 mg m-2 h-1 for P. maximum and P. purpureum respectively at full growth for CO2 and 1.7 μg m-2 h-1and 0.3 μg m-2 h-1 for N2O. Additionally, N2O rates sampled after a typical fertilizer application were significantly greater than at full growth (p=0.0005) with flux rates of 25.2 μg m2h-1 and 30.3 μg m2h-1 for P. maximum and P. purpureum respectively. With a global warming potential of 310 for N2O, even short-term spikes following fertilizer application can cause long lasting effects of GHG emission from agricultural soils. CH4 flux was negligible for all species on the Oahu plots during these sample periods. Globally, water limitation is a major factor influencing the potential productivity of agricultural crops and the sustainability of

  3. Application of wood chips for soil mulching in the cultivation of ornamental grasses

    Directory of Open Access Journals (Sweden)

    Henschke Monika

    2016-12-01

    Full Text Available A mulch is a layer of material applied to the surface of the soil. Mulching plays an important role in the maintenance of green spaces. Organic materials are still sought for the preparation of mulches. Recently interest in wood chips has grown. The aim of the study was to determine the effect of mulching with pine and birch chips on the contents of phenolic compounds in the soil, as well as on the growth and flowering of ornamental grasses – Bouteloua gracilis (Kunth. Lag. ex Griffiths, Panicum virgatum L. and Pennisetum alopecuroides L. The content of phenolic compounds in the soil steadily increased from spring to autumn. Mulching led to a substantial increase in the level of phenolic compounds. In the first year of cultivation more phenolic compounds were released by chips of pine than birch, while in the second year this difference did not occur. Mulching had a negative impact on the growth and flowering of ornamental grasses, especially in the first year of cultivation. Ornamental grass sensitivity to the substances released from mulches decreased with the age of the plants and was dependent on the species – Bouteloua gracilis was found to be particularly sensitive.

  4. The grasses (Poaceae) of the Colombian guayana: analyses on their composition, richness, endemism, and invasion

    International Nuclear Information System (INIS)

    Canas, Diego Giraldo

    2010-01-01

    The checklist of grasses from Colombian Guayana is presented. In all, 152 species, 69 genera, and six subfamilies were recorded. Thus, in the Colombian Guayana is represented the 18.7 and 43.7% of the species and genera of Colombian grasses, respectively. The subfamilies with the highest number of species were Panicoideae (110 species/46 genera), Chloridoideae (21/9), and Bambusoideae (11/9). The most diverse genera were Paspalum (19 species), Panicum (16), Axonopus (14), Eragrostis (9), and Digitaria (8). Nineteen species are introduced and naturalized in the Colombian Guayana, which represent 12.5% of the agrostological flora for the Colombian Guayana. There were 8 endemic species (5.3% of Colombian Guayanan grasses). In addition, some species are reported for the first time for Colombian flora (belonging to Axonopus, Cyphonanthus, Gymnopogon, and Paspalum), and some species are new to science (belonging to Axonopus, Digitaria, Eragrostis, and Sacciolepis). On the other hand, some preliminary biogeographical aspect are analyzed Flora of Colombia,

  5. Atividade de fosfatases em gramíneas forrageiras em resposta à disponibilidade de fósforo no solo e à altura de corte das plantas Phosphatase activity in forage grasses as influenced by soil phosphorus availability and plant cutting height

    Directory of Open Access Journals (Sweden)

    Flancer Novais Nunes

    2008-10-01

    intenso, independentemente da dose de P, tanto Brachiaria quanto Panicum apresentaram menor EUP. Isso ocorreu associado à maior atividade das enzimas APase e RNase, indicando que outros mecanismos relacionados com a adaptação das plantas a baixas disponibilidades de P podem estar envolvidos.The nutrient use efficiency, expressed by the ratio between the produced biomass and nutrient content, is an important adaptive characteristic of plants, particularly of those cultivated in low-fertility soils. A high P-use efficiency (PUE is conferred by high P remobilization rates, i.e., P transport to regions of greater metabolic demand in the plant. High P remobilization rates have been associated with high acid phosphatase (APase and ribonuclease (RNase enzyme activities. In our study, we evaluated the activity of these enzymes in Brachiaria decumbens, with a low, and Panicum maximum cv Tanzânia, with a high P demand, cultivated in soil treated with different P rates and cut at different heights. The experiment was carried out in a greenhouse, using B-horizon samples of a clayey Yellow-Red Latosol. The treatments consisted of a factorial combination of two grasses, three P rates (100, 200 and 500 mg dm-3 and three cutting heights: no cutting, 15 and 30 cm above the soil surface for Brachiaria, and no cutting, 20 and 40 cm for Panicum. The experimental units consisted of pots with 10 dm³ soil, with 10 plants each. Results indicated that there was no significant difference between biomass production of the two grasses, but the P application resulted in a higher biomass yield and P shoot concentration. The biomass production of plants cut at a lower height was smaller and P concentrations in shoots were higher. A significant effect of P rates on the APase and the RNase activities was observed in both forages. In plants grown at the lowest P rate enzyme activities and PUE were the highest. The activity of both phosphatases decreased with plant aging. In the treatment with the

  6. Selecting, Establishing, and Managing Switchgrass (Panicum virgatum) for Biofuels

    Science.gov (United States)

    Parrish, David J.; Fike, John H.

    Switchgrass is being widely considered as a feedstock for biofuel production. Much remains to be learned about ideal feedstock characteristics, but switchgrass offers many advantages already and can perhaps be manipulated to offer more. When planning to grow switchgrass, select a cultivar that is well adapted to the location - generally a lowland cultivar for the southern United States and an upland cultivar at higher latitudes. Plant non-dormant seed after soils are well warmed, preferably with no-till methods and always with good weed control. Except for weeds, few pests appear to be widespread; but disease and insect pests could become more important as acreages increase. Fertilization requirements are relatively low, with 50 kg N/ha/year being a good “generic” recommendation where a single harvest is taken after plants have senesced; more will be needed if biomass is harvested while still green. Switchgrass should be harvested no more than twice per year and may generally be expected to produce 12 to ≥20 mg/ha/year across its usual range of distribution. A single harvest may provide for maximum sustainable yields - especially if the harvest is taken after tops die back at the end of the season. Several harvesting technologies are available, but the preferred technology may depend on logistics and economics associated with the local processing point, or biorefinery.

  7. The Potential of Cellulosic Ethanol Production from Grasses in Thailand

    Directory of Open Access Journals (Sweden)

    Jinaporn Wongwatanapaiboon

    2012-01-01

    Full Text Available The grasses in Thailand were analyzed for the potentiality as the alternative energy crops for cellulosic ethanol production by biological process. The average percentage composition of cellulose, hemicellulose, and lignin in the samples of 18 types of grasses from various provinces was determined as 31.85–38.51, 31.13–42.61, and 3.10–5.64, respectively. The samples were initially pretreated with alkaline peroxide followed by enzymatic hydrolysis to investigate the enzymatic saccharification. The total reducing sugars in most grasses ranging from 500–600 mg/g grasses (70–80% yield were obtained. Subsequently, 11 types of grasses were selected as feedstocks for the ethanol production by simultaneous saccharification and cofermentation (SSCF. The enzymes, cellulase and xylanase, were utilized for hydrolysis and the yeasts, Saccharomyces cerevisiae and Pichia stipitis, were applied for cofermentation at 35°C for 7 days. From the results, the highest yield of ethanol, 1.14 g/L or 0.14 g/g substrate equivalent to 32.72% of the theoretical values was obtained from Sri Lanka ecotype vetiver grass. When the yields of dry matter were included in the calculations, Sri Lanka ecotype vetiver grass gave the yield of ethanol at 1,091.84 L/ha/year, whereas the leaves of dwarf napier grass showed the maximum yield of 2,720.55 L/ha/year (0.98 g/L or 0.12 g/g substrate equivalent to 30.60% of the theoretical values.

  8. The potential of cellulosic ethanol production from grasses in Thailand.

    Science.gov (United States)

    Wongwatanapaiboon, Jinaporn; Kangvansaichol, Kunn; Burapatana, Vorakan; Inochanon, Ratanavalee; Winayanuwattikun, Pakorn; Yongvanich, Tikamporn; Chulalaksananukul, Warawut

    2012-01-01

    The grasses in Thailand were analyzed for the potentiality as the alternative energy crops for cellulosic ethanol production by biological process. The average percentage composition of cellulose, hemicellulose, and lignin in the samples of 18 types of grasses from various provinces was determined as 31.85-38.51, 31.13-42.61, and 3.10-5.64, respectively. The samples were initially pretreated with alkaline peroxide followed by enzymatic hydrolysis to investigate the enzymatic saccharification. The total reducing sugars in most grasses ranging from 500-600 mg/g grasses (70-80% yield) were obtained. Subsequently, 11 types of grasses were selected as feedstocks for the ethanol production by simultaneous saccharification and cofermentation (SSCF). The enzymes, cellulase and xylanase, were utilized for hydrolysis and the yeasts, Saccharomyces cerevisiae and Pichia stipitis, were applied for cofermentation at 35 °C for 7 days. From the results, the highest yield of ethanol, 1.14 g/L or 0.14 g/g substrate equivalent to 32.72% of the theoretical values was obtained from Sri Lanka ecotype vetiver grass. When the yields of dry matter were included in the calculations, Sri Lanka ecotype vetiver grass gave the yield of ethanol at 1,091.84 L/ha/year, whereas the leaves of dwarf napier grass showed the maximum yield of 2,720.55 L/ha/year (0.98 g/L or 0.12 g/g substrate equivalent to 30.60% of the theoretical values).

  9. Extending juvenility in grasses

    Energy Technology Data Exchange (ETDEWEB)

    Kaeppler, Shawn; de Leon Gatti, Natalia; Foerster, Jillian

    2017-04-11

    The present invention relates to compositions and methods for modulating the juvenile to adult developmental growth transition in plants, such as grasses (e.g. maize). In particular, the invention provides methods for enhancing agronomic properties in plants by modulating expression of GRMZM2G362718, GRMZM2G096016, or homologs thereof. Modulation of expression of one or more additional genes which affect juvenile to adult developmental growth transition such as Glossy15 or Cg1, in conjunction with such modulation of expression is also contemplated. Nucleic acid constructs for down-regulation of GRMZM2G362718 and/or GRMZM2G096016 are also contemplated, as are transgenic plants and products produced there from, that demonstrate altered, such as extended juvenile growth, and display associated phenotypes such as enhanced yield, improved digestibility, and increased disease resistance. Plants described herein may be used, for example, as improved forage or feed crops or in biofuel production.

  10. Breeding for Grass Seed Yield

    DEFF Research Database (Denmark)

    Boelt, Birte; Studer, Bruno

    2010-01-01

    Seed yield is a trait of major interest for many fodder and amenity grass species and has received increasing attention since seed multiplication is economically relevant for novel grass cultivars to compete in the commercial market. Although seed yield is a complex trait and affected...... important aspects and components affecting the seed yield potential and the agronomic and environmental aspects affecting the utilization and realization of the seed yield potential. Finally, it discusses the potential of plant breeding to sustainably improve total seed yield in fodder and amenity grasses....

  11. DESEMPENHOS TÉCNICOS E ECONÔMICOS DA CONSORCIAÇÃO DE MILHO COM FORRAGEIRAS DOS GÊNEROS Panicum E Brachiaria EM SISTEMA DE INTEGRAÇÃO LAVOURA-PECUÁRIA TECHNICAL AND ECONOMIC PERFORMANCE OF CORN INTERCROPPED WITH Panicum AND Brachiaria FORAGE IN CROP-LIVESTOCK INTEGRATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Carlos Alessandro Chioderoli

    2009-10-01

    .

    Palavras-chave: Margem de contribuição; produtividade de grãos; relação custo/benefício; sistema plantio direto; Zea mays L.

    The objective of this research was to evaluate the technical and economic performance of methods for corn cropping with Brachiaria and Panicum genuses forages, in crop-livestock integration systems under no-tillage. The experiment was conducted in Selvíria, Mato Grosso do Sul State, Brazil, in a Distroferric Red Latosol (Oxisol, during the growing seasons of 2007 and 2008. The experimental design was a randomized block with four replications. The treatments consisted of eight methods for growing corn intercropped with Panicum maximum cv. Tanzania, Panicum maximum cv. Mombaça, Brachiaria brizantha cv. Marandu, and Brachiaria ruziziensis, sown simultaneously or at side dressing nitrogen fertilization, besides single grown corn. The operating cost analysis was based on prices of inputs and operations, and the revenue at the average price for corn in São Paulo State. The decreasing cost-benefit ratio and the best economic returns, obtained due to higher index of contribution margin, determined the most feasible cropping methods. The Panicum maximum cv. Mombaça and Brachiaria brizantha cv. Marandu, intercropped simultaneously with corn, provided less grain yield than single grown corn. As related to

  12. Grass fungal endophytes and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Craven, Kelly

    2015-03-10

    The invention provides isolated fungal endophytes and synthetic combinations thereof with host grass plants. Methods for inoculating grass plant with the endophytes, for propagating the grass-endophyte combinations, and for producing feeds and biofuels from grass-endophyte combinations are also provided.

  13. Composição químico-bromatológica, digestibilidade e degradação in situ da dieta de ovinos em capim-tanzânia sob três frequências de desfolhação Chemical composition, digestibility and in situ degradation of sheep diet on Tanzania grass with three defoliation frequencies

    Directory of Open Access Journals (Sweden)

    Bruno Stefano Miranda Valente

    2010-01-01

    Full Text Available Objetivou-se avaliar a composição químico-bromatológica, a digestibilidade e a degradação in situ da matéria seca da dieta consumida por ovinos em pastagem de Panicum maximum cv. tanzânia sob três frequências de desfolhação, determinadas pela interceptação da radiação fotossinteticamente ativa (IRFA de 85, 95 e 97% no 1º e 4º dias de pastejo. O delineamento experimental foi inteiramente casualizado com arranjo fatorial 3 × 2 (três frequências de desfolhação e dois dias de pastejo, com quatro repetições (piquetes por tratamento. Para determinação da composição químico-bromatológica e da digestibilidade e ensaio de cinética de degradação da matéria seca da dieta, foi realizada uma simulação de pastejo no 1º e 4º dias de ocupação. A diminuição da frequência de desfolhação piorou a composição químico-bromatológica, a digestibilidade e a degradação do capim-tanzânia. Recomenda-se frequência de desfolhação no capim-tanzânia menor ou igual a 95% de interceptação da radiação fotossinteticamente ativa visando à manutenção da qualidade do pasto.The objective of this study was to evaluate the chemical composition, digestibility and in situ degradation of dry matter of the diet consumed by sheep grazing on Panicum maximum cv. Tanzania under three defoliation frequencies, determined by the interception of the photosynthetically active radiation in the canopy (PAR of 85, 95 and 97% on the first and fourth days of the grazing period. A randomized complete design in a 3 × 2 factorial arrangement (three defoliation frequencies and two days grazing, with four replications (poles. To determine the chemical composition, digestibility and an in situ dry matter degradation trial, a grazing simulation was carried out on the 1st and 4th days. Reduced defoliation frequency decreased the chemical composition, digestibility and in situ degradation of the diet. Thus defoliation frequency of tanzania grass is

  14. Perfilhamento e características estruturais do capim-Mombaça, adubado com fontes de fósforo, em pastejo - DOI: 10.4025/actascianimsci.v30i1.3593 Tillering and structural characteristics of Mombaça grass fertilized with phosphate sources, under grazing - DOI: 10.4025/actascianimsci.v30i1.3593

    Directory of Open Access Journals (Sweden)

    Sandra Galbeiro

    2008-06-01

    Full Text Available O experimento foi realizado no período de dezembro de 2002 a abril de 2003, com o objetivo de avaliar o efeito de diferentes fontes de fósforo (termofosfato magnesiano Yoorin®, fosfato natural de Gafsa, um formulado de superfosfato simples + superfosfato triplo e tratamento-controle, sem aplicação de fósforo em função dos meses de avaliação, sobre o índice de área foliar (IAF, peso e número de perfilhos, percentagem de lâmina foliares e colmo totais (%, razão lâmina foliar/colmo, no capim-Mombaça (Panicum maximum Jacq. cv. Mombaça. O delineamento experimental utilizado foi em blocos ao acaso com três repetições. As fontes de fósforo influenciaram (p ® proporcionou o menor peso por perfilho; no tratamento Gafsa, houve o menor número de perfilhos. Houve o efeito de período (p The experiment was conducted from December/2002 to April/2003, with the objective of evaluating the effects of different phosphate sources (Yoorin® magnesium thermophosphate, Simple Superphosphate + Triple Superphosphate, Gafsa natural phosphate, and control – no phosphate application as a function of the evaluation months, on leaf area index (LAI, tiller weight (P and number, percentage of total leaf and stem (% and leaf blade/stem ratio of Mombaça grass (Panicum maximum Jacq. cv. Mombaça. The experiment design was a randomized block, with three replications. Phosphate sources influenced (p ® had less weight per tiller, and the Gafsa phosphate obtained the lowest number of tillers. There was a period effect (p < 0.05 for all evaluated variables. The lowest LAI was observed in April, and the highest in February, showing adaptation to a new reproductive cycle. There was little phosphorous influence on tillering; however, soluble phosphate increased the weight of tillers, while the period increased leaf presence.

  15. Disponibilidade de fósforo pelos extratores de Mehlich 1 e Resina em Latossolo Vermelho Amarelo, álico cultivado com três gramíneras forrageiras Availability of phosphorus by the Mehlich 1 and Resin methods in a Red Yellow Latosol cultivated with three grasses

    Directory of Open Access Journals (Sweden)

    L. de A. Corrêa

    1993-09-01

    Full Text Available É apresentado um estudo comparando os extratores de Mehlich 1 e Resina na avaliação do P disponível em Latossolo Vermelho Amarelo, álico cultivado com as gramíneas Brachiaria decumbens Stapf, Brachiaria brizantha (Hochst. Stapf. cv. Marandu e Panicum maximum Jacq. Foram utilizados dados de dois ensaios de adubação fosfatada, um realizado em vasos em casa de vegetação e o outro no campo. Correlações entre o P extraído através de cada extrator com a produção relativa de matéria seca, o P extraído peía planta e o teor de P na planta, permitiram determinar o extrator de P mais eficiente. Os resultados mostraram que os dois extratores foram eficientes e similares na avaliação do P disponível para as três gramíneas forrageiras, sendo que o método da Resina apresentou maior capacidade de extração do P aplicado.This study was undertaken to compare the Mehlich 1 and Resin methods in the evaluation of available P in a Red Yellow Latossol, cultivated with Brachiaría decumbens Stapf., Brachiaría brízantha (Hochst. Stapf cv. Marandu and Panicum maximum Jacq. Data of two experiments of P fertilization were utilized, one carried out in the greenhouse and the other in the field. Correlations between the amount of P extracted by each extrator with the relative production of dry matter and of the amount of P extracted by the plant and the level of P in the plant, were used to determine the efficiency of the extractors. The results showed that both extractors were efficient and similar for the evaluation of the P availability of the three grasses, but the resin method had a greater extraction capacity of the P applied.

  16. Efecto de la suplementación con residuos de destilería del maíz en el comportamiento de novillas en una asociación de gramínea y leucaena Effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena

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    Tania Sánchez

    2010-09-01

    Full Text Available El objetivo del presente trabajo fue evaluar el efecto de la suplementación con residuos de destilería del maíz en el comportamiento de novillas, en una asociación de gramínea y leucaena. El estudio se realizó en un área de la Estación Experimental "Indio Hatuey", en el municipio de Perico, provincia de Matanzas, Cuba. La especie de pasto predominante fue Panicum maximum cv. Likoni y como leguminosa Leucaena leucocephala. Se estudiaron 18 novillas, distribuidas en un diseño completamente aleatorizado en tres grupos de seis animales; el grupo control no recibió suplementación (A y los otros dos grupos se suplementaron con residuos de destilería del maíz en un 10% (B y 20% (C de los requerimientos de proteína con relación al peso vivo. Se determinó la composición química, la disponibilidad de materia seca, la ganancia de peso vivo, la infestaci��n parasitaria y el hematocrito. Al analizar las ganancias diarias por tratamiento se encontraron diferencias significativas (PThe objective of this work was to evaluate the effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena. The study was conducted in an area of the Experimental Station "Indio Hatuey" , Perico municipality, Matanzas province, Cuba. The prevailing pasture species was Panicum maximum cv. Likoni and as legume, Leucaena leucocephala. Eighteen heifers, distributed in a completely randomized design in three groups of six animals, were used; the control group did not receive supplementation (A, and the other two groups were supplemented with corn distillery residues in 10% (B and 20% (C of the protein requirements with regards to live weight. The chemical composition, dry matter availability, live weight gain, parasite infestation and hematocrit were determined. When analyzing the daily gain per treatments, significant differences (P<0,05 were found and the highest values were obtained in treatment C

  17. Selection and validation of reference genes for gene expression analysis in switchgrass (Panicum virgatum) using quantitative real-time RT-PCR.

    Science.gov (United States)

    Gimeno, Jacinta; Eattock, Nicholas; Van Deynze, Allen; Blumwald, Eduardo

    2014-01-01

    Switchgrass (Panicum virgatum) has received a lot of attention as a forage and bioenergy crop during the past few years. Gene expression studies are in progress to improve new traits and develop new cultivars. Quantitative real time PCR (qRT-PCR) has emerged as an important technique to study gene expression analysis. For accurate and reliable results, normalization of data with reference genes is essential. In this work, we evaluate the stability of expression of genes to use as reference for qRT-PCR in the grass P. virgatum. Eleven candidate reference genes, including eEF-1α, UBQ6, ACT12, TUB6, eIF-4a, GAPDH, SAMDC, TUA6, CYP5, U2AF, and FTSH4, were validated for qRT-PCR normalization in different plant tissues and under different stress conditions. The expression stability of these genes was verified by the use of two distinct algorithms, geNorm and NormFinder. Differences were observed after comparison of the ranking of the candidate reference genes identified by both programs but eEF-1α, eIF-4a, CYP5 and U2AF are ranked as the most stable genes in the samples sets under study. Both programs discard the use of SAMDC and TUA6 for normalization. Validation of the reference genes proposed by geNorm and NormFinder were performed by normalization of transcript abundance of a group of target genes in different samples. Results show similar expression patterns when the best reference genes selected by both programs were used but differences were detected in the transcript abundance of the target genes. Based on the above research, we recommend the use of different statistical algorithms to identify the best reference genes for expression data normalization. The best genes selected in this study will help to improve the quality of gene expression data in a wide variety of samples in switchgrass.

  18. Grass and weed killer poisoning

    Science.gov (United States)

    ... medlineplus.gov/ency/article/002838.htm Grass and weed killer poisoning To use the sharing features on this page, please enable JavaScript. Many weed killers contain dangerous chemicals that are harmful if ...

  19. On-Farm Preference by West African Dwarf Goats and In Vitro ...

    African Journals Online (AJOL)

    Centosema molle; Pueraria phaseoloides) and grasses (Pennisetum purpureum; Panicum maximum) were studied for proximate composition, acceptability, preference, and in vitro gas production characteristics using eight West African dwarf ...

  20. Downregulation of the UDP-arabinomutase gene in switchgrass (Panicum virgatum L. results in increased cell wall lignin while reducing arabinose-glycans

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    Jonathan Duran Willis

    2016-10-01

    Full Text Available Switchgrass (Panicum virgatum L. is a C4 perennial prairie grass and a lignocellulosic biofuels feedstock. Saccharification and biofuel yields are inhibited by the plant cell wall’s natural recalcitrance against enzymatic degradation. Plant hemicellulose polysaccharides such as arabinoxylans structurally support and crosslink other cell wall polymers. Grasses have predominately Type II cell walls that are abundant in arabinoxylan, which comprise nearly 25% of aboveground biomass. A primary component of arabinoxylan synthesis is uridine diphosphate (UDP linked to arabinofuranose (Araf. A family of UDP-arabinopyranose mutase/reversible glycosylated polypeptides (UAM/RGPs catalyze the interconversion between UDP-arabinopyranose (UDP-Arap and UDP-Araf. In switchgrass we knocked down expression of the endogenous PvUAM1 gene via RNAi to investigate its role in cell wall recalcitrance in the feedstock. PvUAM1 encodes a switchgrass homolog of UDP-arabinose mutase, which converts UDP-Arap to UDP-Araf. Each transgenic line contained between one to at least seven T-DNA insertions, resulting in some cases, a 95% reduction of native PvUAM1 transcript in stem internodes. Transgenic plants had increased pigmentation in vascular tissues at nodes, but were otherwise morphologically similar to non-transgenics. There was decreased cell wall-associated arabinose in leaves and stems by over 50%, but there was an increase in cellulose in these organs. In addition, there was a commensurate change in arabinose side chain extension. Cell wall lignin composition was altered with a concurrent increase in lignin content and transcript abundance of lignin biosynthetic genes in mature tillers. Enzymatic saccharification efficiency was unchanged in the transgenic plants relative to the control, but had increased glucose in cell walls. The increased glucose detected in stems and leaves indicates that attenuation of PvUAM1 expression might have downstream effects on starch

  1. Composição química de capim-tanzânia adubado com nitrogênio e fósforo Chemical composition of Tanzania grass fertilized with nitrogen and phosphorus

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    Ronaldo Silva Sousa

    2010-06-01

    Full Text Available Avaliaram-se os teores de matéria seca (MS, proteína bruta (PB, fibra em detergente neutro (FDN, nutrientes digestíveis totais (NDT, cálcio (Ca, fósforo (P e magnésio (Mg na parte aérea do capim-tanzânia (Panicum maximum adubado com nitrogênio e fósforo durante o período de verão/outono. Utilizou-se o delineamento inteiramente casualizado, em esquema fatorial 4 × 3, com quatro doses de nitrogênio (0, 100, 200 e 300 kg/ha/ano e três doses de pentóxido de difósforo (P2O5 (0, 50 e 100 kg/ha/ano, com três repetições. Foram realizados três cortes a 40 cm do solo, a cada 35 dias. Após cada corte, foi realizada adubação, aplicando-se o P2O5 de uma só vez no corte de uniformização e o nitrogênio parcelado em três vezes. As doses de nitrogênio não afetaram os teores de magnésio e reduziram os teores de matéria seca, cálcio e fósforo, enquanto a adubação fosfatada aumentou o teor de fósforo. A adubação teve efeito quadrático nos teores de PB, FDN e NDT, melhorando a qualidade da forragem conforme aumentaram as doses, principalmente de nitrogênio. Nas condições edafoclimáticas estudadas, recomenda-se que o capim-tanzânia seja adubado com 300 kg de N/ha e 100 kg de P2O5/ha.It was evaluated in this work the contents of dry matter (DM, crude protein (CP, neutral detergent fiber (NDF, total digestible nutrients (TDN, calcium (Ca, phosphorus (P and magnesium (Mg in the aerial section of the Tanzania grass (Panicum maximum, fertilized with nitrogen and phosphorus during the summer and autumn. The experimental design was complete randomized, with a 4 × 3 factorial scheme, and four N rates (0, 100, 200, and 300 kg/ha/year, and three pentoxide diphosphorus (P2O5 rates (0, 50, and 100 kg/ha/year, with three replicates. Three cuts were made at 40 cm of the soil, every 35 days. After each cut, the fertilization was accomplished, and P2O5 was applied only once on the uniformed cut and N was parceled in three times

  2. Chemical Composition, Dry Matter Intake by West African Dwarf ...

    African Journals Online (AJOL)

    The experiment was conducted to determine dry matter intake (DMI) by West African dwarf (WAD) goats, chemical composition, in vitro gas production and dry matter digestibility of Panicum maximum (common name: Guinea grass or Panicum) with graded levels of palm kernel cake (PKC). Five diets were evaluated: ...

  3. Grass and forb species for revegetation of mixed soil-lignite overburden in East Central Texas

    Energy Technology Data Exchange (ETDEWEB)

    Skousen, J.G.; Call, C.A. (West Virginia University, Morgantown, WV (USA). Division of Plant and Soil Sciences)

    Ten grasses and seven forbs were seeded into mixed soil-lignite overburden in the Post Oak Savannah region of Texas and monitored for establishment and growth over a 3-year period without fertilization. Buffelgrass (Cenchrus ciliaris), green sprangletop (Leptochloa dubia), switchgrass (Panicum virgatum), and kleingrass (P. coloratum) developed monotypic stands with sufficent density, aerial cover, and aboveground biomass to stabilize the mixed soil-lignite overburden surface by the end of the first growing season. Plant mortality eliminated buffelgrass and green sprangletop stands by the end of the third growing season. Indiangrass (Sorghastrum nutans) developed a satisfactory stand by the end of the third growing season, while Oldworld bluestem (Bothriochloa X Dicanthium), yellow bluestem (Bothriochloa ischaemum), and sideoats grama (Bouteloua curtipendula) established at a slower rate. Cover and biomass measurements from an adjacent, unfertilized stand of Coastal bermudagrass (Cynodon dactylon) were compared with those of seeded grasses throughout the study. Partidge pea (Cassia fasciculata) established rapidly and had the greatest cover and biomass of all seeded forbs by the end of the first growing season. Sericea lespedeza (Lespedeza cuneata), Illinois bundleflower (Desmanthus illinoensis), and western indigo (Indigofera miniata) developed adequate stands for surface stabilization by the end of the third growing season, while faseanil indigo (Indigofera suffruticosa), virgata lespedeza (Lespedeza virgata), and awnless bushsunflower (Simsia calva) showed slower establishment. 27 refs., 3 tabs.

  4. Sheep poisoning by Panicum dichotomiflorum in northeastern Brazil Intoxicação por Panicum dicotomiflorum em ovinos na região nordeste

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    Franklin Riet-Correa

    2009-01-01

    Full Text Available Different species of Panicum, including P. dichotomiflorum,have been reported as a cause of photosensitization in sheep, horses, cattle and goats. An outbreak of hepatogenous photosensitization occurred in 3 flocks of hair sheep in the Brazilian semiarid region. Eighty one out of 365 sheep were affected and 39 died. The main affected animals were nursing lambs and sheep younger than one year old. Donkeys, goats and cattle grazing in the same pasture were not affected. Clinical signs were edema of the head, followed by dermatitis, mainly in the face, ears, and croup, ocular discharge, corneal opacity with blindness, and redness of the coronary band and hoof. At necropsy of one affected lamb the liver was yellowish. Upon histologic examination scattered necrotic hepatocytes were observed in the liver and focal areas of necrosis of myocytes appeared in the heart. Samples of P. dicotomiflorum were analyzed by TLC and those containing saponins were isolated by HPLC using RP-C18 column and eluted with a mixture of MeOH and H2O. The isolated compounds were submitted to ¹H and 13C NMR spectroscopy. Reactions were positive to furostanol saponins with the same Rf of the standard protodioscin (0.21 and methylprotodioscin (0.32. The spectroscopic results indicated a mixture of (25R- and (25S-protodioscin isomers in a proportion of 3:1, and methylprotodioscin.Diferentes espécies de Panicum, incluindo P. dichotomiflorum,causam fotossensibilização em ovinos, eqüinos, bovinos e caprinos. Um surto de fotossensibilização hepatógena ocorreu em 3 rebanhos de ovinos no município de Casa Nova, Bahia. Oitenta e um de 365 ovinos adoeceram e 39 morreram. Cordeiros lactentes e ovinos de menos de um ano foram mais afetados. Jumentos, cabras e bovinos que permaneciam nas mesmas pastagens não foram afetados. Clinicamente observou-se edema da face, seguido por dermatite, principalmente da face, orelhas e garupa, corrimento ocular, opacidade da córnea com cegueira

  5. Molecular Evolution of Grass Stomata.

    Science.gov (United States)

    Chen, Zhong-Hua; Chen, Guang; Dai, Fei; Wang, Yizhou; Hills, Adrian; Ruan, Yong-Ling; Zhang, Guoping; Franks, Peter J; Nevo, Eviatar; Blatt, Michael R

    2017-02-01

    Grasses began to diversify in the late Cretaceous Period and now dominate more than one third of global land area, including three-quarters of agricultural land. We hypothesize that their success is likely attributed to the evolution of highly responsive stomata capable of maximizing productivity in rapidly changing environments. Grass stomata harness the active turgor control mechanisms present in stomata of more ancient plant lineages, maximizing several morphological and developmental features to ensure rapid responses to environmental inputs. The evolutionary development of grass stomata appears to have been a gradual progression. Therefore, understanding the complex structures, developmental events, regulatory networks, and combinations of ion transporters necessary to drive rapid stomatal movement may inform future efforts towards breeding new crop varieties. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Effect of microwave freeze drying on quality and energy supply in drying of barley grass.

    Science.gov (United States)

    Cao, Xiaohuang; Zhang, Min; Mujumdar, Arun S; Zhong, Qifeng; Wang, Zhushang

    2018-03-01

    Young barley grass leaves are well-known for containing the antioxidant substances flavonoid and chlorophyll. However, low product quality and energy efficiency exist with respect to the dehydration of barley grass leaves. To improve energy supply and the quality of barley grass, microwave heating instead of contact heat was applied for the freeze drying of barley grass at a pilot scale at 1, 1.5 and 2 W g -1 , respectively; After drying, energy supply and quality parameters of color, moisture content, chlorophyll, flavonoids, odors of dried barley grass were determined to evaluate the feasibility of the study. Microwave freeze drying (MFD) allowed a low energy supply and high contents of chlorophyll and flavonoids. A lightness value of 60.0, a green value of -11.5 and an energy supply of 0.61 kW h -1  g -1 were observed in 1.5 W g -1 MFD; whereas drying time (7 h) decreased by 42% compared to contact heating. Maximum content of flavonoid and chlorophyll was 11.7 and 12.8 g kg -1 barley grass. Microwave heating leads to an odor change larger than that for contact heating observed for the freeze drying of barley grass. MFD retains chlorophyll and flavonoids, as well as colors and odors of samples, and also decreases energy consumption in the freeze drying of barley grass. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  7. The effect of alcoholic extract of Panicum miliaceum L. seed on hippocampus neuronal density in male mouse

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    Arezoo Bornarodi

    2017-08-01

    Full Text Available Background: Hippocampus organization is a part of temporal lobe, which consists of several sections including hippocampal body, dentate gyrus and subiculum. Panicum miliaceum L. contains proteins, vitamins and antioxidants for human health. This study was conducted to examine the effect of the alcoholic extract of the seed of Panicum miliaceum L. plant on hippocampus neuronal density. Materials and Methods: In this experimental study, 24 male mice were divided into 4 groups (n=6, each group. The alcoholic extract of the seed of the Panicum miliaceum L. plant was prepared by soxhlet extraction. Three doses of the extract 25, 50, 75 mg/kg were intraperitoneally injected to 3 treatment groups for 21 days and the control group received normal saline injection. At the end of the experiment, the animals were anesthetized and after perfusion, their brains were removed from the skull. After tissue processing, slices of the brain were prepared and stained. Then, different regions of the hippocampus were photographed and neuronal densities were evaluated. Results: Results showed that the neuronal density in the CA1, CA3 regions of the group treated with 50 mg/kg of the alcoholic extract and in all regions of hippocampus (CA1,CA2,CA3 in groups treated with dose of 75 mg/kg of the alcoholic extract had a significant increase compared to the control group (P<0.05. Conclusion: The present study shows that the alcoholic extract of the seed of Panicum miliaceum L. plant increases neuronal density and induces neurogenesis in the mouse hippocampus.

  8. Performance of beef steers on Smuts finger grass and Nile grass ...

    African Journals Online (AJOL)

    Literature where animal performance is quantified for. Smuts finger grass and Nile grass pastures in South Africa is limited. In some trials, animal performance on Smuts finger grass and/or Nile grass was reported (Rhind & Goodenough,. 1979, Dannhauser, 1982 Grunow, et al., 1984). The ADG achieved by .steers on Smuts ...

  9. Allergenicity and crossreactivity of buffalo grass ( Stenotaphrum ...

    African Journals Online (AJOL)

    Background. In the subtropical climate of South Africa, grasses of the subfamily Panicoideae are predominant. Bermuda grass has previously been shown to be an important local allergen, and immunoglobulin E (IgE) epitopes of Bermuda grass extracts are known to be distinct from those of the Pooid pollen extracts.

  10. Índice climático de crescimento para gramíneas forrageiras no Estado de São Paulo Climatic growth index for forage grasses in the State of São Paulo (Brazil

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    Mário José Pedro Júnior

    1995-01-01

    Full Text Available Utilizou-se o índice climático de crescimento (ICC para gramíneas forrageiras, com base em temperatura, radiação solar e relação entre evapotranspiração real e potencial, a fim de estimar a produção de matéria seca (TAMS de capim-colonião, gordura, jaraguá e pangola através da seguinte equação exponencial: ICC = a EXP (b ICC, onde a e b são constantes que diferem para cada espécie. Determinou-se o índice climático médio mensal para 47 localidades paulistas e regiões limítrofes. A variação espacial do índice para o inverno e para o verão é apresentada em forma de mapas. Os valores de ICC no inverno, período crítico, variaram de 0,1 a 0,15 na região central do Estado; no Norte e no Oeste, foram superiores a 0,15 e, na Serra da Mantiqueira, inferiores a 0,1.The climatic growth index (ICC for forage grasses, based on temperature, solar radiation and the ratio of actual to potential evapotranspiration, was used to estimate dry matter production (TAMS for the following grasses: "colonião" (Panicum maximum Jacq, "gordura" (Melinis minutiflora Pal de Beauv, "jaraguá" (Hyparrhenia rufa (Ness Stapf and "pangola" (Digitaria pentzii Stent, using exponential equations: ICC = a EXP (b ICC, where a and b are constants which differ for each specie analised. The monthly mean climatic index was calculated for forty seven localities of the State of São Paulo and neighbours. Its spatial distribution considering summer and winter is shown as maps. ICC values during the critical season of the winter varied from 0.1 to 0.15 for the central part of the State; at the northern and western regions it is larger than 0.15 and at the "Mantiqueira" mountains it is less than 0.1.

  11. Ensiling of elephant grass with soybean hulls or rice bran

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    India Joelma Gatass Monteiro

    2016-12-01

    Full Text Available The goal was to evaluate the chemical composition and fermentation pattern of elephant grass (Pennisetum purpureum Schum. cv. Roxo silage with different levels of soybean hulls or rice bran. Two trials were conducted, comprising of a completely randomized design, with four replicates each. Treatments consisted on the addition of 0%, 5%, 10%, and 15% of soybean hulls or rice bran to unwilted green elephant grass forage. Large PVC silos were used adopting a density of 600 kg of green mass m-3. The silos were opened 40 days after ensiling. The results revealed that the inclusion of 10% soybean hulls increased elephant grass forage dry matter (DM content to 31%, but did not alter the water soluble carbohydrate (WSC content or buffering capacity. The resultant silages exhibited good fermentation patterns in terms of pH (less than 3.97 and NH3-N (4.07% total N levels. The inclusion of rice bran increased both DM and WSC content in the forage, improving the fermentation pattern of silages (P < 0.05. This too was verified by a pH lower than 3.92 and a maximum NH3-N of 4.23% of the total N. The inclusion of 10% rice bran to the elephant grass improved the nutritional value of the forage to be ensiled and, hence, of the produced silage.

  12. Approximate maximum parsimony and ancestral maximum likelihood.

    Science.gov (United States)

    Alon, Noga; Chor, Benny; Pardi, Fabio; Rapoport, Anat

    2010-01-01

    We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP-hard, so we seek approximate solutions. We formulate the two problems as Steiner tree problems under appropriate distances. The gist of our approach is the succinct characterization of Steiner trees for a small number of leaves for the two distances. This enables the use of known Steiner tree approximation algorithms. The approach leads to a 16/9 approximation ratio for AML and asymptotically to a 1.55 approximation ratio for MP.

  13. Maximum Autocorrelation Factorial Kriging

    DEFF Research Database (Denmark)

    Nielsen, Allan Aasbjerg; Conradsen, Knut; Pedersen, John L.

    2000-01-01

    This paper describes maximum autocorrelation factor (MAF) analysis, maximum autocorrelation factorial kriging, and its application to irregularly sampled stream sediment geochemical data from South Greenland. Kriged MAF images are compared with kriged images of varimax rotated factors from...

  14. Resposta do capim-tanzânia à aplicação de soro ácido de leite Response of tanzânia grass to acid whey application

    Directory of Open Access Journals (Sweden)

    Emerson de Oliveira Gheri

    2003-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a produção de matéria seca e a quantidade de nutrientes extraída por Panicum maximum Jacq. cv. Tanzânia adubado com soro ácido de leite. Amostras de um Argissolo foram coletadas nas profundidades de 0-20, 20-40 e 40-60 cm e colocadas em colunas de PVC compostas por três anéis correspondentes a cada camada. As doses de soro foram definidas com base na concentração de K, de modo a adicionar ao solo 0, 75, 150, 225 e 300 kg/ha de K2O em cada uma das três aplicações: antes da semeadura, após o primeiro e após o segundo corte. O experimento foi realizado em casa de vegetação em delineamento inteiramente ao acaso, durante 112 dias. Após esse período, as colunas foram desmontadas e o solo foi amostrado para análise. A aplicação de soro aumentou a produção de matéria seca; a produção máxima teórica total dos três cortes foi obtida com a aplicação acumulada de 390 m³/ha. As quantidades de K, P e Ca absorvidas pela planta e o teor de K no solo aumentaram significativamente com as doses de soro.The objective of this work was to evaluate the dry matter production and nutrient uptake by Panicum maximum Jacq. cv. Tanzânia fertilized with acid whey. Soil samples of an Alfisol were collected in 0-20 cm, 20-40 cm and 40-60 cm layers and were used to fill PVC columns with three rings with 20 cm height, obeying the collecting depth. The doses of whey were based on its K content and 0, 75, 150, 225 and 300 kg/ha K2O were added in each application: the first one applied before sowing, the second after the first cut and the third after the second cut. The experiment was carried out in a greenhouse in a completely randomized design during 112 days. After this period, the rings of the columns were separated and soil samples were taken for analysis. The dry matter production increased with whey application and the total maximum theoretical production was obtained with the cumulative application of

  15. Comparative analysis of Panicum streak virus and Maize streak virus diversity, recombination patterns and phylogeography

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    Markham Peter G

    2009-11-01

    Full Text Available Abstract Background Panicum streak virus (PanSV; Family Geminiviridae; Genus Mastrevirus is a close relative of Maize streak virus (MSV, the most serious viral threat to maize production in Africa. PanSV and MSV have the same leafhopper vector species, largely overlapping natural host ranges and similar geographical distributions across Africa and its associated Indian Ocean Islands. Unlike MSV, however, PanSV has no known economic relevance. Results Here we report on 16 new PanSV full genome sequences sampled throughout Africa and use these together with others in public databases to reveal that PanSV and MSV populations in general share very similar patterns of genetic exchange and geographically structured diversity. A potentially important difference between the species, however, is that the movement of MSV strains throughout Africa is apparently less constrained than that of PanSV strains. Interestingly the MSV-A strain which causes maize streak disease is apparently the most mobile of all the PanSV and MSV strains investigated. Conclusion We therefore hypothesize that the generally increased mobility of MSV relative to other closely related species such as PanSV, may have been an important evolutionary step in the eventual emergence of MSV-A as a serious agricultural pathogen. The GenBank accession numbers for the sequences reported in this paper are GQ415386-GQ415401

  16. The Genetic Basis of Upland/Lowland Ecotype Divergence in Switchgrass (Panicum virgatum

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    Elizabeth R. Milano

    2016-11-01

    Full Text Available The evolution of locally adapted ecotypes is a common phenomenon that generates diversity within plant species. However, we know surprisingly little about the genetic mechanisms underlying the locally adapted traits involved in ecotype formation. The genetic architecture underlying locally adapted traits dictates how an organism will respond to environmental selection pressures, and has major implications for evolutionary ecology, conservation, and crop breeding. To understand the genetic architecture underlying the divergence of switchgrass (Panicum virgatum ecotypes, we constructed a genetic mapping population through a four-way outbred cross between two northern upland and two southern lowland accessions. Trait segregation in this mapping population was largely consistent with multiple independent loci controlling the suite of traits that characterizes ecotype divergence. We assembled a joint linkage map using ddRADseq, and mapped quantitative trait loci (QTL for traits that are divergent between ecotypes, including flowering time, plant size, physiological processes, and disease resistance. Overall, we found that most QTL had small to intermediate effects. While we identified colocalizing QTL for multiple traits, we did not find any large-effect QTL that clearly controlled multiple traits through pleiotropy or tight physical linkage. These results indicate that ecologically important traits in switchgrass have a complex genetic basis, and that similar loci may underlie divergence across the geographic range of the ecotypes.

  17. The Genetic Basis of Upland/Lowland Ecotype Divergence in Switchgrass (Panicum virgatum)

    Science.gov (United States)

    Milano, Elizabeth R.; Lowry, David B.; Juenger, Thomas E.

    2016-01-01

    The evolution of locally adapted ecotypes is a common phenomenon that generates diversity within plant species. However, we know surprisingly little about the genetic mechanisms underlying the locally adapted traits involved in ecotype formation. The genetic architecture underlying locally adapted traits dictates how an organism will respond to environmental selection pressures, and has major implications for evolutionary ecology, conservation, and crop breeding. To understand the genetic architecture underlying the divergence of switchgrass (Panicum virgatum) ecotypes, we constructed a genetic mapping population through a four-way outbred cross between two northern upland and two southern lowland accessions. Trait segregation in this mapping population was largely consistent with multiple independent loci controlling the suite of traits that characterizes ecotype divergence. We assembled a joint linkage map using ddRADseq, and mapped quantitative trait loci (QTL) for traits that are divergent between ecotypes, including flowering time, plant size, physiological processes, and disease resistance. Overall, we found that most QTL had small to intermediate effects. While we identified colocalizing QTL for multiple traits, we did not find any large-effect QTL that clearly controlled multiple traits through pleiotropy or tight physical linkage. These results indicate that ecologically important traits in switchgrass have a complex genetic basis, and that similar loci may underlie divergence across the geographic range of the ecotypes. PMID:27613751

  18. Transcriptomic analysis, genic SSR development, and genetic diversity of proso millet (Panicum miliaceum; Poaceae).

    Science.gov (United States)

    Hou, Siyu; Sun, Zhaoxia; Li, Yaoshen; Wang, Yijie; Ling, Hubin; Xing, Guofang; Han, Yuanhuai; Li, Hongying

    2017-07-01

    Proso millet ( Panicum miliaceum ; Poaceae) is a minor crop with good nutritional qualities and strong tolerance to drought stress and soil infertility. However, studies on genetic diversity have been limited due to a lack of efficient genetic markers. Illumina sequencing technology was used to generate short read sequences of proso millet, and de novo transcriptome assemblies were used to develop a de novo assembly of proso millet. Genic simple sequence repeat (SSR) markers were identified and used to detect polymorphism among 56 accessions. Population structure and genetic similarity coefficient were estimated. In total, 25,341 unique gene sequences and 4724 SSR loci were obtained from the transcriptome, of which 229 pairs of SSR primers were validated, which resulted in 14 polymorphic genic SSR primers exhibiting 43 total alleles. According to the ratio of polymorphic markers (6.1%, 14/229), there are potentially 288 polymorphic genic SSR markers available for genetic assay development in the future. Bayesian population analyses showed that the 56 accessions comprised two distinct groups. A genetic structure and cluster assay indicated that the accessions from the Loess Plateau of China shared a high genetic similarity coefficient with those from other regions and that there was no correlation between genetic diversity and geographic origin. The transcriptome sequencing data and millet-specific SSR markers developed in this study establish an excellent resource for gene discovery and may improve the development of breeding programs in proso millet in the future.

  19. Evaluation of ecophysiological characteristics of intercropping of millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L.

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    A. Ghanbari

    2016-04-01

    Full Text Available In order to evaluate millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L. intercropping, an experiment was conducted during 2008-2009 at Agriculture Research Center of Zabol University, Iran. The experiment was as randomized complete block design with three replications. Treatment s consisted of sole crop of millet, sole crop of cowpea, 25% millet + 100% cowpea, 50% millet + 50% cowpea, 75% millet + 100% cowpea and 100% millet + 100% cowpea. The results showed that intercropping treatments had significant effect (P < 1% on millet and bean seed yield, LER, dry matter of weeds, PAR, temperature and (P < 5% on soil moisture content. The highest seed yield of millet and cowpea obtained from treatments of sole crops. The LER for most intercrops was greater than one which indicated that intercropping had advantage over sole crop. For weeds management and control the results indicated that weed suppressing effects in intercropping treatments is better than sole crops treatment, so that the lowest dry matter of weeds obtained from 100% millet + 100% cowpea treatment. PAR in all of stages showed that the highest PAR interception obtained from intercropping treatments specially 100% millet + 100% cowpea treatment. In addition to the lowest of soil moisture content and temperature obtained from this treatment.

  20. Switchgrass (Panicum virgatum) Intercropping within Managed Loblolly Pine (Pinus taeda) Does Not Affect Wild Bee Communities.

    Science.gov (United States)

    Campbell, Joshua W; Miller, Darren A; Martin, James A

    2016-11-04

    Intensively-managed pine ( Pinus spp.) have been shown to support diverse vertebrate communities, but their ability to support invertebrate communities, such as wild bees, has not been well-studied. Recently, researchers have examined intercropping switchgrass ( Panicum virgatum ), a native perennial, within intensively managed loblolly pine ( P. taeda ) plantations as a potential source for cellulosic biofuels. To better understand potential effects of intercropping on bee communities, we investigated visitation of bees within three replicates of four treatments of loblolly pine in Mississippi, U.S.A.: 3-4 year old pine plantations and 9-10 year old pine plantations with and without intercropped switchgrass. We used colored pan traps to capture bees during the growing seasons of 2013 and 2014. We captured 2507 bees comprised of 18 different genera during the two-year study, with Lasioglossum and Ceratina being the most common genera captured. Overall, bee abundances were dependent on plantation age and not presence of intercropping. Our data suggests that switchgrass does not negatively impact or promote bee communities within intensively-managed loblolly pine plantations.

  1. Satellite panicum mosaic virus coat protein enhances the performance of plant virus gene vectors.

    Science.gov (United States)

    Everett, Anthany L; Scholthof, Herman B; Scholthof, Karen-Beth G

    2010-01-05

    The coat protein of satellite panicum mosaic virus (SPCP) is known to effectively protect its cognate RNA from deleterious events, and here, we tested its stabilizing potential for heterologous virus-based gene vectors in planta. In support of this, a Potato virus X (PVX) vector carrying the SPMV capsid protein (PVX-SPCP) gene was stable for at least three serial systemic passages through Nicotiana benthamiana. To test the effect of SPCP in trans, PVX-SPCP was co-inoculated onto N. benthamiana together with a Tomato bushy stunt virus (TBSV) vector carrying a green fluorescent protein (GFP) gene that normally does not support systemic GFP expression. In contrast, co-inoculation of TBSV-GFP plus PVX-SPCP resulted in GFP accumulation and concomitant green fluorescent spots in upper, non-inoculated leaves in a temperature-responsive manner. These results suggest that the multifaceted SPMV CP has intriguing effects on virus-host interactions that surface in heterologous systems.

  2. Exogenous GR24 Alleviates Cadmium Toxicity by Reducing Cadmium Uptake in Switchgrass (Panicum virgatum) Seedlings.

    Science.gov (United States)

    Tai, Zhenglan; Yin, Xinqiang; Fang, Zhigang; Shi, Gaoling; Lou, Laiqing; Cai, Qingsheng

    2017-07-29

    Strigolactones (SLs) are classified into plant hormones, playing a key role as a mediator of plant growth in response to several abiotic stresses, including drought and salinity. However, the role of SLs in cadmium (Cd)-induced stress to plants is still unknown. The physiological responses of switchgrass ( Panicum virgatum ) stressed in 10 μmol L -1 Cd to exogenous synthetic SLs analog, GR24 were studied in hydroponics. The Cd stress significantly caused the adverse effects on plant growth and root morphology, inhibited photosynthesis, but boosted lipid peroxidation of Switchgrass seedlings. After treatment of 1 μmol L -1 GR24, the above adverse effects caused by Cd stress were significantly alleviated, mainly reflects in improvement of shoot biomass, relative water content, root development, chlorophyll contents, activities of typical antioxidant enzymes, nutrient uptake. The reason for exogenous GR24 alleviating cadmium toxicity might be owing to that exogenous GR24 promoted the content of endogenous SLs, increased some essential element Fe (iron), Zn (zinc), Mn (manganese) and Cu (copper) uptake and reduced cadmium uptake, accumulation and partition in shoot of switchgrass seedlings.

  3. Grass production and decomposition in Southern Guinea savanna, Nigeria.

    Science.gov (United States)

    Ohiagu, C E; Wood, T G

    1979-01-01

    Annual grass production in ungrazed plots was 2,731 kg ha -1 , litter production was 1,619 kg ha -1 and decomposition was 1,789 kg ha -1 . In grazed plots the corresponding figures were 3,157 kg ha -1 , 1,440 kg ha -1 , and 1,475 kg ha -1 respectively; cattle consumed 1,405 kg ha -1 . Litter disappearance was greatest in the dry season: 1,226 kg ha -1 (69% of the annual total) disappearing in the 4 months of December to March in the ungrazed plots, largely due to consumption (790 kg ha -1 in December to March) by fungus-growing termites (Macrotermitinae). A positive linear relationship was found between maximum grass biomass and annual rainfall in West Africa.

  4. Coherent Microwave Scattering Model of Marsh Grass

    Science.gov (United States)

    Duan, Xueyang; Jones, Cathleen E.

    2017-12-01

    In this work, we developed an electromagnetic scattering model to analyze radar scattering from tall-grass-covered lands such as wetlands and marshes. The model adopts the generalized iterative extended boundary condition method (GIEBCM) algorithm, previously developed for buried cylindrical media such as vegetation roots, to simulate the scattering from the grass layer. The major challenge of applying GIEBCM to tall grass is the extremely time-consuming iteration among the large number of short subcylinders building up the grass. To overcome this issue, we extended the GIEBCM to multilevel GIEBCM, or M-GIEBCM, in which we first use GIEBCM to calculate a T matrix (transition matrix) database of "straws" with various lengths, thicknesses, orientations, curvatures, and dielectric properties; we then construct the grass with a group of straws from the database and apply GIEBCM again to calculate the T matrix of the overall grass scene. The grass T matrix is transferred to S matrix (scattering matrix) and combined with the ground S matrix, which is computed using the stabilized extended boundary condition method, to obtain the total scattering. In this article, we will demonstrate the capability of the model by simulating scattering from scenes with different grass densities, different grass structures, different grass water contents, and different ground moisture contents. This model will help with radar experiment design and image interpretation for marshland and wetland observations.

  5. Comportamento ingestivo e digestão de nutrientes em bovinos de corte alimentados com silagem de capim - DOI: 10.4025/actascianimsci.v31i4.5782 Intake behavior and nutrient digestion of beef cattle fed with grass silage - DOI: 10.4025/actascianimsci.v31i4.5782

    Directory of Open Access Journals (Sweden)

    Maity Zopollatto

    2009-10-01

    Full Text Available Avaliou-se o efeito do teor de matéria seca, uso de inoculante bacteriano e a redução do tamanho de partículas da silagem de capim-Tanzânia (Panicum maximum, sobre os parâmetros digestivos. Utilizaram-se sete novilhos da raça Nelore, em delineamento experimental Quadrado Latino 7 x 7. Os tratamentos foram: T1: Umidade original, partícula menor, sem inoculante bacteriano; T2: Umidade original, partícula menor, com inoculante bacteriano; T3: Emurchecido, partícula maior, com inoculante bacteriano; T4: Emurchecido, partícula maior, sem inoculante bacteriano; T5: Umidade original, partícula maior, com inoculante bacteriano; T6: Umidade original, partícula maior, sem inoculante bacteriano; T7: Umidade original, partícula maior, sem inoculante bacteriano, com milheto. Os tratamentos não influenciaram as taxas de passagem de sólidos (2,4% hora-1 e de líquidos (3,2% hora-1, o consumo de matéria seca (1,1% do PV e nem o comportamento ingestivo. Observaram-se os seguintes tempos (minutos dia-1 e taxas (min kg MS-1 de ingestão de MS (293 e 68; de ruminação (432 e 102 e de mastigação (725 e 170, respectivamente. Os valores médios de digestibilidade da MS (61,4%, FDA (59,7%, PB (43,9% e FDN (60,3% não diferiram entre os tratamentos. Os procedimentos adotados na ensilagem não resultaram em alterações significativas nos parâmetros avaliados.The main objective was to study the effect of dry matter content, the addition of bacterial inoculant and particle size reduction on Tanzania grass (Panicum maximum silage on digestive parameters. Seven ruminally cannulated Nellore beef steers were randomly assigned to a 7 x 7 Latin Square design. Treatments were described as follows: T1: wet forage + small particle; T2: T1 + inoculant; T4: wilting + large particle; T3: T4 + inoculant; T6: wet forage + large particle; T5: T6 + inoculant; T7: T6 + ground pearl millet grain. The ruminal passage rate of solid (2.35% h-1 and liquid (3.17% h-1 phases

  6. Effects of rye grass coverage on soil loss from loess slopes

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    Yuequn Dong

    2015-09-01

    Full Text Available Vegetative coverage is commonly used to reduce urban slope soil erosion. Laboratory experimental study on soil erosion under grass covered slopes is conventionally time and space consuming. In this study, a new method is suggested to study the influences of vegetation coverage on soil erosion from a sloped loess surface under three slope gradients of 5°, 15°, and 25°; four rye grass coverages of 0%, 25%, 50%, and 75%; and three rainfall intensities of 60, 90, and 120 mm/h with a silt-loamy loess soil. Rye grasses were planted in the field with the studied soil before being transplanted into a laboratory flume. Grass was allowed to resume growth for a period before the rain simulation experiment. Results showed that the grass cover reduced soil erosion by 63.90% to 92.75% and sediment transport rate by 80.59% to 96.17% under different slope gradients and rainfall intensities. The sediment concentration/sediment transport rate from bare slope was significantly higher than from a grass-covered slope. The sediment concentration/transport rate from grass-covered slopes decreased linearly with grass coverage and increased with rainfall intensity. The sediment concentration/transport rate from the bare slope increased as a power function of slope and reached the maximum value at the gradient of about 25°, whereas that from grass-covered slope increased linearly and at much lower levels. The results of this study can be used to estimate the effect of vegetation on soil erosion from loess slopes.

  7. Desempenho de bovinos em capim-tanzânia adubado com nitrogênio ou consorciado com Estilosantes Performance of beef cattle grazing Tanzania grass fertilized with nitrogen or intercropped with Stylo

    Directory of Open Access Journals (Sweden)

    Clóves Cabreira Jobim

    2011-03-01

    Full Text Available Com este estudo objetivou-se avaliar a massa seca de forragem e lâminas foliares, ganho médio diário, taxa de lotação e ganho de peso vivo em capim-tanzânia (Panicum maximum Jacq. no período de novembro de 2008 a julho de 2009 sob lotação contínua. Utilizou-se delineamento experimental em blocos ao acaso em parcela subdivididas, com três repetições, e como tratamentos: Tanzânia + Estilosantes Campo Grande; Tanzânia + 75kg/ha de N; Tanzânia + 150kg/ha de N e Tanzânia + 225kg/ha de N, e nas sub-parcelas os períodos do ano: primavera, verão e outono. No verão, a massa seca de forragem e lâminas foliares foram superiores à primavera e outono. O tratamento com 225kg de N apresentou maior massa seca de forragem e massa seca de lâminas foliares no verão e outono. Obteve-se maior ganho médio diário no verão. Na primavera e no verão não houve diferença entre os tratamentos para o ganho médio diário, e no outono o tratamento com 225kg/ha de N foi superior. A taxa de lotação foi semelhante no verão e outono, e menor na primavera. O tratamento com 225kg de N apresentou maior taxa de lotação na primavera e verão. O tratamento com 225kg de N apresentou maior ganho de peso vivo no outono, na primavera e verão o 150 kg de N foi semelhante. A disponibilidade de massa seca de forragem e o desempenho animal proporcionado pelo Estilosantes foram equivalentes à adubação nitrogenada até a dose de 75kg de N.This study aimed to evaluate the dry mass of forage and leaf blade dry mass, average daily gain, stocking rate and live weight gain in Tanzania grass (Panicum maximum Jacq. from November/2008 to July/2009, on continuous stocking. The experimental design was a split-plot arrangement in a randomized blocks design, with three replications and four treatments: Tanzania + Campo Grande Stylo; Tanzania + 75kg/ha of N; Tanzania + 150kg/ha of N and Tanzania + 225kg/ha of N, subplots were the seasons of the year: Spring, Summer and

  8. Analyzing rasters, vectors and time series using new Python interfaces in GRASS GIS 7

    Science.gov (United States)

    Petras, Vaclav; Petrasova, Anna; Chemin, Yann; Zambelli, Pietro; Landa, Martin; Gebbert, Sören; Neteler, Markus; Löwe, Peter

    2015-04-01

    GRASS GIS 7 is a free and open source GIS software developed and used by many scientists (Neteler et al., 2012). While some users of GRASS GIS prefer its graphical user interface, significant part of the scientific community takes advantage of various scripting and programing interfaces offered by GRASS GIS to develop new models and algorithms. Here we will present different interfaces added to GRASS GIS 7 and available in Python, a popular programming language and environment in geosciences. These Python interfaces are designed to satisfy the needs of scientists and programmers under various circumstances. PyGRASS (Zambelli et al., 2013) is a new object-oriented interface to GRASS GIS modules and libraries. The GRASS GIS libraries are implemented in C to ensure maximum performance and the PyGRASS interface provides an intuitive, pythonic access to their functionality. GRASS GIS Python scripting library is another way of accessing GRASS GIS modules. It combines the simplicity of Bash and the efficiency of the Python syntax. When full access to all low-level and advanced functions and structures from GRASS GIS library is required, Python programmers can use an interface based on the Python ctypes package. Ctypes interface provides complete, direct access to all functionality as it would be available to C programmers. GRASS GIS provides specialized Python library for managing and analyzing spatio-temporal data (Gebbert and Pebesma, 2014). The temporal library introduces space time datasets representing time series of raster, 3D raster or vector maps and allows users to combine various spatio-temporal operations including queries, aggregation, sampling or the analysis of spatio-temporal topology. We will also discuss the advantages of implementing scientific algorithm as a GRASS GIS module and we will show how to write such module in Python. To facilitate the development of the module, GRASS GIS provides a Python library for testing (Petras and Gebbert, 2014) which

  9. Early lignin pathway enzymes and routes to chlorogenic acid in switchgrass (Panicum virgatum L.).

    Science.gov (United States)

    Escamilla-Treviño, Luis L; Shen, Hui; Hernandez, Timothy; Yin, Yanbin; Xu, Ying; Dixon, Richard A

    2014-03-01

    Studying lignin biosynthesis in Panicum virgatum (switchgrass) has provided a basis for generating plants with reduced lignin content and increased saccharification efficiency. Chlorogenic acid (CGA, caffeoyl quinate) is the major soluble phenolic compound in switchgrass, and the lignin and CGA biosynthetic pathways potentially share intermediates and enzymes. The enzyme hydroxycinnamoyl-CoA: quinate hydroxycinnamoyltransferase (HQT) is responsible for CGA biosynthesis in tobacco, tomato and globe artichoke, but there are no close orthologs of HQT in switchgrass or in other monocotyledonous plants with complete genome sequences. We examined available transcriptomic databases for genes encoding enzymes potentially involved in CGA biosynthesis in switchgrass. The protein products of two hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyltransferase (HCT) genes (PvHCT1a and PvHCT2a), closely related to lignin pathway HCTs from other species, were characterized biochemically and exhibited the expected HCT activity, preferring shikimic acid as acyl acceptor. We also characterized two switchgrass coumaroyl shikimate 3'-hydroxylase (C3'H) enzymes (PvC3'H1 and PvC3'H2); both of these cytochrome P450s had the capacity to hydroxylate 4-coumaroyl shikimate or 4-coumaroyl quinate to generate caffeoyl shikimate or CGA. Another switchgrass hydroxycinnamoyl transferase, PvHCT-Like1, is phylogenetically distant from HCTs or HQTs, but exhibits HQT activity, preferring quinic acid as acyl acceptor, and could therefore function in CGA biosynthesis. The biochemical features of the recombinant enzymes, the presence of the corresponding activities in plant protein extracts, and the expression patterns of the corresponding genes, suggest preferred routes to CGA in switchgrass.

  10. Physiological Evaluation of Alkali-Salt Tolerance of Thirty Switchgrass (Panicum virgatum Lines.

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    Guofu Hu

    Full Text Available Soil salt-alkalization is a major limiting factor for crop production in many regions. Switchgrass (Panicum virgatum L. is a warm-season C4 perennial rhizomatous bunchgrass and a target lignocellulosic biofuel species. The objective of this study was to evaluate relative alkali-salt tolerance among 30 switchgrass lines. Tillers of each switchgrass line were transplanted into pots filled with fine sand. Two months after transplanting, plants at E5 developmental stage were grown in either half strength Hoagland's nutrient solution with 0 mM Na+ (control or half strength Hoagland's nutrient solution with 150 mM Na+ and pH of 9.5 (alkali-salt stress treatment for 20 d. Alkali-salt stress damaged cell membranes [higher electrolyte leakage (EL], reduced leaf relative water content (RWC, net photosynthetic rate (Pn, stomatal conductance (gs, and transpiration rate (Tr. An alkali-salt stress tolerance trait index (ASTTI for each parameter was calculated based on the ratio of the value under alkali-salt stress and the value under non-stress conditions for each parameter of each line. Relative alkali-salt tolerance was determined based on principal components analysis and cluster analysis of the physiological parameters and their ASTTI values. Significant differences in alkali-salt stress tolerance were found among the 30 lines. Lowland lines TEM-SEC, Alamo, TEM-SLC and Kanlow were classified as alkali-salt tolerant. In contrast, three lowland lines (AM-314/MS-155, BN-13645-64 and two upland lines (Caddo and Blackwell-1 were classified as alkali-salt sensitive. The results suggest wide variations exist in alkali-salt stress tolerance among the 30 switchgrass lines. The approach of using a combination of principal components and cluster analysis of the physiological parameters and related ASTTI is feasible for evaluating alkali-salt tolerance in switchgrass.

  11. The Mechanisms of Salinity Tolerance in the Xero-halophyte Blue Panicgrass (Panicum antidotale Retz

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    Hamid R. ESHGHIZADEH

    2012-05-01

    Full Text Available Identifying the physiological traits associated with salt tolerance is important in optimal management of biosaline systems and optimum utilization of saline water resources in dry and saline areas. Therefore, some indices of photosynthetic activity, dry matter production and accumulation of sodium and potassium ions in Blue panicgrass (Panicum antidotale Retz were evaluated in five levels of salinity treatment (0, 70, 140, 210 and 280 mM NaCl solution under greenhouse conditions. The results showed that at 28 and 35 days after salt stress, plant leaf area reduced in the highest salinity treatment, 93 and 96% respectively, compared with control. Leaf stomatal conductance, CO2 fixation and quantum efficiency of photosystem II were decreased by increasing salinity. It caused also a reduction in chlorophyll content (Chl a, Chl b in leaves of Blue panicgrass. Content of carotenoids showed binary patterns to different salinity levels, slightly increased in 70-140 mM NaCl and decreased again in 210-280 mM, respectively. Increasing levels of salinity, increased sodium content in both roots and shoots but the shoots potassium content decreased. Decline in photosynthesis indices caused the reduction of root and shoot dry weight. This decrease resulted from lower leaf area (r=0.91**, lower stomatal conductance (r=0.78**, lower CO2 fixed in photosynthesis (r=0.63**, lower quantum efficiency of photosystem II (r=0.54** and lower Chl a (r=0.45**, respectively. Data analysis base on using stepwise regression introduced leaf area (?=0.560, chlorophyll a content (?=0.245 and shoot potassium content (?= 0.264 as main effective components of salinity tolerance in Blue panicgrass.

  12. Physiological Evaluation of Alkali-Salt Tolerance of Thirty Switchgrass (Panicum virgatum) Lines.

    Science.gov (United States)

    Hu, Guofu; Liu, Yiming; Zhang, Xunzhong; Yao, Fengjiao; Huang, Yan; Ervin, Erik H; Zhao, Bingyu

    2015-01-01

    Soil salt-alkalization is a major limiting factor for crop production in many regions. Switchgrass (Panicum virgatum L.) is a warm-season C4 perennial rhizomatous bunchgrass and a target lignocellulosic biofuel species. The objective of this study was to evaluate relative alkali-salt tolerance among 30 switchgrass lines. Tillers of each switchgrass line were transplanted into pots filled with fine sand. Two months after transplanting, plants at E5 developmental stage were grown in either half strength Hoagland's nutrient solution with 0 mM Na+ (control) or half strength Hoagland's nutrient solution with 150 mM Na+ and pH of 9.5 (alkali-salt stress treatment) for 20 d. Alkali-salt stress damaged cell membranes [higher electrolyte leakage (EL)], reduced leaf relative water content (RWC), net photosynthetic rate (Pn), stomatal conductance (gs), and transpiration rate (Tr). An alkali-salt stress tolerance trait index (ASTTI) for each parameter was calculated based on the ratio of the value under alkali-salt stress and the value under non-stress conditions for each parameter of each line. Relative alkali-salt tolerance was determined based on principal components analysis and cluster analysis of the physiological parameters and their ASTTI values. Significant differences in alkali-salt stress tolerance were found among the 30 lines. Lowland lines TEM-SEC, Alamo, TEM-SLC and Kanlow were classified as alkali-salt tolerant. In contrast, three lowland lines (AM-314/MS-155, BN-13645-64) and two upland lines (Caddo and Blackwell-1) were classified as alkali-salt sensitive. The results suggest wide variations exist in alkali-salt stress tolerance among the 30 switchgrass lines. The approach of using a combination of principal components and cluster analysis of the physiological parameters and related ASTTI is feasible for evaluating alkali-salt tolerance in switchgrass.

  13. Checklist of Serengeti Ecosystem Grasses.

    Science.gov (United States)

    Williams, Emma Victoria; Elia Ntandu, John; Ficinski, Paweł; Vorontsova, Maria

    2016-01-01

    We present the first taxonomic checklist of the Poaceae species of the Serengeti, Tanzania. A review of the literature and herbarium specimens recorded 200 species of grasses, in line with similar studies in other parts of East Africa. The checklist is supported by a total of 939 herbarium collections. Full georeferenced collection data is made available alongside a summary checklist in pdf format. More than a quarter of the species are known from a single collection highlighting the need for further research, especially concerning the rare species and their distribution.

  14. Checklist of Serengeti Ecosystem Grasses

    Science.gov (United States)

    Ficinski, Paweł; Vorontsova, Maria

    2016-01-01

    Abstract We present the first taxonomic checklist of the Poaceae species of the Serengeti, Tanzania. A review of the literature and herbarium specimens recorded 200 species of grasses, in line with similar studies in other parts of East Africa. The checklist is supported by a total of 939 herbarium collections. Full georeferenced collection data is made available alongside a summary checklist in pdf format. More than a quarter of the species are known from a single collection highlighting the need for further research, especially concerning the rare species and their distribution. PMID:27226761

  15. Green grasses as light harvesters in dye sensitized solar cells

    Science.gov (United States)

    Shanmugam, Vinoth; Manoharan, Subbaiah; Sharafali, A.; Anandan, Sambandam; Murugan, Ramaswamy

    2015-01-01

    Chlorophylls, the major pigments presented in plants are responsible for the process of photosynthesis. The working principle of dye sensitized solar cell (DSSC) is analogous to natural photosynthesis in light-harvesting and charge separation. In a similar way, natural dyes extracted from three types of grasses viz. Hierochloe Odorata (HO), Torulinium Odoratum (TO) and Dactyloctenium Aegyptium (DA) were used as light harvesters in dye sensitized solar cells (DSSCs). The UV-Vis absorption spectroscopy, Fourier transform infrared (FT-IR), and liquid chromatography-mass spectrometry (LC-MS) were used to characterize the dyes. The electron transport mechanism and internal resistance of the DSSCs were investigated by the electrochemical impedance spectroscopy (EIS). The performance of the cells fabricated with the grass extract shows comparable efficiencies with the reported natural dyes. Among the three types of grasses, the DSSC fabricated with the dye extracted from Hierochloe Odorata (HO) exhibited the maximum efficiency. LC-MS investigations indicated that the dominant pigment present in HO dye was pheophytin a (Pheo a).

  16. Tolerable Time-Varying Overflow on Grass-Covered Slopes

    Directory of Open Access Journals (Sweden)

    Steven A. Hughes

    2015-03-01

    Full Text Available Engineers require estimates of tolerable overtopping limits for grass-covered levees, dikes, and embankments that might experience steady overflow. Realistic tolerance estimates can be used for both resilient design and risk assessment. A simple framework is developed for estimating tolerable overtopping on grass-covered slopes caused by slowly-varying (in time overtopping discharge (e.g., events like storm surges or river flood waves. The framework adapts the well-known Hewlett curves of tolerable limiting velocity as a function of overflow duration. It has been hypothesized that the form of the Hewlett curves suggests that the grass erosion process is governed by the flow work on the slope above a critical threshold velocity (referred to as excess work, and the tolerable erosional limit is reached when the cumulative excess work exceeds a given value determined from the time-dependent Hewlett curves. The cumulative excess work is expressed in terms of overflow discharge above a critical discharge that slowly varies in time, similar to a discharge hydrograph. The methodology is easily applied using forecast storm surge hydrographs at specific locations where wave action is minimal. For preliminary planning purposes, when storm surge hydrographs are unavailable, hypothetical equations for the water level and overflow discharge hydrographs are proposed in terms of the values at maximum overflow and the total duration of overflow. An example application is given to illustrate use of the methodology.

  17. Green grasses as light harvesters in dye sensitized solar cells.

    Science.gov (United States)

    Shanmugam, Vinoth; Manoharan, Subbaiah; Sharafali, A; Anandan, Sambandam; Murugan, Ramaswamy

    2015-01-25

    Chlorophylls, the major pigments presented in plants are responsible for the process of photosynthesis. The working principle of dye sensitized solar cell (DSSC) is analogous to natural photosynthesis in light-harvesting and charge separation. In a similar way, natural dyes extracted from three types of grasses viz. Hierochloe Odorata (HO), Torulinium Odoratum (TO) and Dactyloctenium Aegyptium (DA) were used as light harvesters in dye sensitized solar cells (DSSCs). The UV-Vis absorption spectroscopy, Fourier transform infrared (FT-IR), and liquid chromatography-mass spectrometry (LC-MS) were used to characterize the dyes. The electron transport mechanism and internal resistance of the DSSCs were investigated by the electrochemical impedance spectroscopy (EIS). The performance of the cells fabricated with the grass extract shows comparable efficiencies with the reported natural dyes. Among the three types of grasses, the DSSC fabricated with the dye extracted from Hierochloe Odorata (HO) exhibited the maximum efficiency. LC-MS investigations indicated that the dominant pigment present in HO dye was pheophytin a (Pheo a). Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Water requirement of four cutting grasses water efficiency in the Colombian dry Caribbean region

    Directory of Open Access Journals (Sweden)

    José Murillo Solano

    2014-01-01

    Full Text Available In the Colombia Caribbean region’s low rainfall (600 to 1500 mm and irregular distribution leads to a drastic reduction in availability of fodder. The project objectives were to determine the water requirements of 4 grasses, evaluate water - production equations and the effect of water deficit on yield. Spray gradient methodolog y was used on a split plot design with 4 repetitions and 6 treatments for 100, 80, 60, 40, 20 y 0% of the water deficit. In summer season from January to April, the average daily water consumption of grasses purple King grass, green King grass, Elephant and Maralfalfa was 4,7; 4,6; 4,6 y 4,9 mm/day with average K factors 0,68; 0,66; 0,67 y 0,73 respectively. Dry matter productions with indicated water consumptions were higher in 301, 317, 140 and 415% respectively than productions in treatments without irrigation. At maximum rainfall (April - June the average water requirements of these grasses in the same old order was 4,25; 4,23; 4,22; 4,54 mm/day with average K factors of 0,75; 0,75; 0,74 and 0,81. Yields in dry matter with previous consumptions exceeded 146, 178, 141 y 204% respectively to no irrigation treatments. Under irrigated conditions Maralfalfa is recommended while under rainfed conditions Elephant grass is recommended.

  19. The complex subcellular distribution of satellite panicum mosaic virus capsid protein reflects its multifunctional role during infection

    International Nuclear Information System (INIS)

    Qi Dong; Omarov, Rustem T.; Scholthof, Karen-Beth G.

    2008-01-01

    Satellite panicum mosaic virus (SPMV) depends on its helper Panicum mosaic virus for replication and movement in host plants. The positive-sense single-stranded genomic RNA of SPMV encodes a 17-kDa capsid protein (CP) to form 16-nm virions. We determined that SPMV CP accumulates in both cytosolic and non-cytosolic fractions, but cytosolic accumulation of SPMV CP is exclusively associated with virions. An N-terminal arginine-rich motif (N-ARM) on SPMV CP is used to bind its cognate RNA and to form virus particles. Intriguingly, virion formation is dispensable for successful systemic SPMV RNA accumulation, yet this process still depends on an intact N-ARM. In addition, a C-terminal domain on the SPMV CP is necessary for self-interaction. Biochemical fractionation and fluorescent microscopy of green fluorescent protein-tagged SPMV CP demonstrated that the non-cytosolic SPMV CP is associated with the cell wall, the nucleus and other membranous organelles. To our knowledge, this is the first report that a satellite virus CP not only accumulates exclusively as virions in the cytosol but also is directed to the nucleolus and membranes. That SPMV CP is found both in the nucleus and the cell wall suggests its involvement in viral nuclear import and cell-to-cell transport

  20. Influence of grass species and stage of maturity at ensiling on intake ...

    African Journals Online (AJOL)

    The aim of this study was to compare intake and partial digestibility of organic matter (OM) and nitrogen (N) of two ensiled tropical grass species,. P. maximum and D. eriantha, made either at the boot or full bloom stage of growth. Intake and digestibility were determined by the double marker technique where Yb and Cr were ...

  1. Star grass (Cynodon nlemfuensis Harl.) In the Eastern Cape. | A.J. ...

    African Journals Online (AJOL)

    The growth and production of star grass in the coastal belt north east of East London, and the live mass production of tollies on this pasturage over a period of four years are discussed. The period of maximum production takes place from January to the end of February, after which it drops sharply. A live mass gain of 998 ...

  2. Defoliation height and potassium fertilization of Mulato II grass

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Avelino Cabral

    2017-08-01

    Full Text Available A pot trial in greenhouse conditions was carried out to identify at which defoliation height Mulato II grass (Urochloa hibrida cv. Mulato II should be managed and to determine whether potassium fertilization is necessary in soil with high potassium content. The experiment was carried out in a greenhouse in a randomized block design with six treatments and five replications. Treatments consisted of a 3 × 2 factorial arrangement, with three defoliation heights (50, 65, and 80 cm and with or without potassium maintenance fertilization. The production characteristics and chemical composition of the forage plant were evaluated. There was no interaction effect between defoliation height and fertilization with or without potassium on any of the analyzed variables, except for mineral content in Mulato II grass. The tillers and leaves number, shoot dry matter, leaf+sheath, root system, and residue were influenced by defoliation heights and potassium fertilization, except for the leaf blades and root dry matter, leaf blade/stem+sheath ratio, and leaves number, which were not influenced by potassium fertilization. Higher shoot dry matter was observed at the heights of 65 and 80 cm; however, comparing these two heights, leaf + sheath dry matter was lower at 65 cm. Regarding the grass’s chemical composition, there was an increase in neutral and acid detergent fiber and indigestible neutral detergent fiber contents as the defoliation height increased, which resulted in lower production of potentially digestible dry matter, which can compromise the potential use of the forage by animals. Among evaluated treatments, Mulato II grass defoliation is recommended for a maximum height of 65 cm. Potassium fertilization increases the yield and the potentially digestible dry matter content of Mulato II grass, even when cultivated in soil with high potassium content.

  3. SQ grass sublingual allergy immunotherapy tablet for disease-modifying treatment of grass pollen allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Dahl, Ronald; Roberts, Graham; de Blic, Jacques

    2016-01-01

    BACKGROUND: Allergy immunotherapy is a treatment option for allergic rhinoconjunctivitis (ARC). It is unique compared with pharmacotherapy in that it modifies the immunologic pathways that elicit an allergic response. The SQ Timothy grass sublingual immunotherapy (SLIT) tablet is approved in North...... America and throughout Europe for the treatment of adults and children (≥5 years old) with grass pollen-induced ARC. OBJECTIVE: The clinical evidence for the use of SQ grass SLIT-tablet as a disease-modifying treatment for grass pollen ARC is discussed in this review. METHODS: The review included...... the suitability of SQ grass SLIT-tablet for patients with clinically relevant symptoms to multiple Pooideae grass species, single-season efficacy, safety, adherence, coseasonal initiation, and cost-effectiveness. The data from the long-term SQ grass SLIT-tablet clinical trial that evaluated a clinical effect 2...

  4. Toward Genomics-Based Breeding in C3 Cool-Season Perennial Grasses

    Science.gov (United States)

    Talukder, Shyamal K.; Saha, Malay C.

    2017-01-01

    Most important food and feed crops in the world belong to the C3 grass family. The future of food security is highly reliant on achieving genetic gains of those grasses. Conventional breeding methods have already reached a plateau for improving major crops. Genomics tools and resources have opened an avenue to explore genome-wide variability and make use of the variation for enhancing genetic gains in breeding programs. Major C3 annual cereal breeding programs are well equipped with genomic tools; however, genomic research of C3 cool-season perennial grasses is lagging behind. In this review, we discuss the currently available genomics tools and approaches useful for C3 cool-season perennial grass breeding. Along with a general review, we emphasize the discussion focusing on forage grasses that were considered orphan and have little or no genetic information available. Transcriptome sequencing and genotype-by-sequencing technology for genome-wide marker detection using next-generation sequencing (NGS) are very promising as genomics tools. Most C3 cool-season perennial grass members have no prior genetic information; thus NGS technology will enhance collinear study with other C3 model grasses like Brachypodium and rice. Transcriptomics data can be used for identification of functional genes and molecular markers, i.e., polymorphism markers and simple sequence repeats (SSRs). Genome-wide association study with NGS-based markers will facilitate marker identification for marker-assisted selection. With limited genetic information, genomic selection holds great promise to breeders for attaining maximum genetic gain of the cool-season C3 perennial grasses. Application of all these tools can ensure better genetic gains, reduce length of selection cycles, and facilitate cultivar development to meet the future demand for food and fodder. PMID:28798766

  5. Toward Genomics-Based Breeding in C3 Cool-Season Perennial Grasses

    Directory of Open Access Journals (Sweden)

    Shyamal K. Talukder

    2017-07-01

    Full Text Available Most important food and feed crops in the world belong to the C3 grass family. The future of food security is highly reliant on achieving genetic gains of those grasses. Conventional breeding methods have already reached a plateau for improving major crops. Genomics tools and resources have opened an avenue to explore genome-wide variability and make use of the variation for enhancing genetic gains in breeding programs. Major C3 annual cereal breeding programs are well equipped with genomic tools; however, genomic research of C3 cool-season perennial grasses is lagging behind. In this review, we discuss the currently available genomics tools and approaches useful for C3 cool-season perennial grass breeding. Along with a general review, we emphasize the discussion focusing on forage grasses that were considered orphan and have little or no genetic information available. Transcriptome sequencing and genotype-by-sequencing technology for genome-wide marker detection using next-generation sequencing (NGS are very promising as genomics tools. Most C3 cool-season perennial grass members have no prior genetic information; thus NGS technology will enhance collinear study with other C3 model grasses like Brachypodium and rice. Transcriptomics data can be used for identification of functional genes and molecular markers, i.e., polymorphism markers and simple sequence repeats (SSRs. Genome-wide association study with NGS-based markers will facilitate marker identification for marker-assisted selection. With limited genetic information, genomic selection holds great promise to breeders for attaining maximum genetic gain of the cool-season C3 perennial grasses. Application of all these tools can ensure better genetic gains, reduce length of selection cycles, and facilitate cultivar development to meet the future demand for food and fodder.

  6. Accelerated development in Johnsongrass seedlings (Sorghum halepense suppresses the growth of native grasses through size-asymmetric competition.

    Directory of Open Access Journals (Sweden)

    Susanne Schwinning

    Full Text Available Invasive plant species often dominate native species in competition, augmenting other potential advantages such as release from natural enemies. Resource pre-emption may be a particularly important mechanism for establishing dominance over competitors of the same functional type. We hypothesized that competitive success of an exotic grass against native grasses is mediated by establishing an early size advantage. We tested this prediction among four perennial C4 warm-season grasses: the exotic weed Johnsongrass (Sorghum halepense, big bluestem (Andropogon gerardii, little bluestem (Schizachyrium scoparius and switchgrass (Panicum virgatum. We predicted that a the competitive effect of Johnsongrass on target species would be proportional to their initial biomass difference, b competitive effect and response would be negatively correlated and c soil fertility would have little effect on competitive relationships. In a greenhouse, plants of the four species were grown from seed either alone or with one Johnsongrass neighbor at two fertilizer levels and periodically harvested. The first two hypotheses were supported: The seedling biomass of single plants at first harvest (50 days after seeding ranked the same way as the competitive effect of Johnsongrass on target species: Johnsongrass < big bluestem < little bluestem/switchgrass, while Johnsongrass responded more strongly to competition from Johnsongrass than from native species. At final harvest, native plants growing with Johnsongrass attained between 2-5% of their single-plant non-root biomass, while Johnsongrass growing with native species attained 89% of single-plant non-root biomass. Fertilization enhanced Johnsongrass' competitive effects on native species, but added little to the already severe competitive suppression. Accelerated early growth of Johnsongrass seedlings relative to native seedlings appeared to enable subsequent resource pre-emption. Size-asymmetric competition and resource

  7. Bioenergy production from roadside grass

    DEFF Research Database (Denmark)

    Meyer, Ane Katharina Paarup; Ehimen, Ehiazesebhor Augustine; Holm-Nielsen, Jens Bo

    2014-01-01

    .5–3.0% of the present national energy production based on biogas. The estimated values for the energy return on invested energy (EROEI) was found to range from 2.17 to 2.88. The measured contents of heavy metals in the roadside vegetation was seen not to exceed the legislative levels for what can be applied......This paper presents a study of the feasibility of utilising roadside vegetation for biogas production in Denmark. The potential biomass yield, methane yields, and the energy balances of using roadside grass for biogas production was investigated based on spatial analysis. The results show...... that the potential annual yield of biomass obtainable from roadside verges varies widely depending on the local conditions. The net energy gain (NEG) from harvest, collection, transport, storage and digestion of roadside vegetation was estimated to range from 60,126–121,476 GJ, corresponding to 1...

  8. Maximum likelihood scaling (MALS)

    NARCIS (Netherlands)

    Hoefsloot, Huub C. J.; Verouden, Maikel P. H.; Westerhuis, Johan A.; Smilde, Age K.

    2006-01-01

    A filtering procedure is introduced for multivariate data that does not suffer from noise amplification by scaling. A maximum likelihood principal component analysis (MLPCA) step is used as a filter that partly removes noise. This filtering can be used prior to any subsequent scaling and

  9. Functional Maximum Autocorrelation Factors

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Nielsen, Allan Aasbjerg

    2005-01-01

    \\verb+~+\\$\\backslash\\$cite{ramsay97} to functional maximum autocorrelation factors (MAF)\\verb+~+\\$\\backslash\\$cite{switzer85,larsen2001d}. We apply the method to biological shapes as well as reflectance spectra. {\\$\\backslash\\$bf Methods}. MAF seeks linear combination of the original variables that maximize autocorrelation between...

  10. Maximum likely scale estimation

    DEFF Research Database (Denmark)

    Loog, Marco; Pedersen, Kim Steenstrup; Markussen, Bo

    2005-01-01

    A maximum likelihood local scale estimation principle is presented. An actual implementation of the estimation principle uses second order moments of multiple measurements at a fixed location in the image. These measurements consist of Gaussian derivatives possibly taken at several scales and...

  11. Grass leaves as potential hominin dietary resources.

    Science.gov (United States)

    Paine, Oliver C C; Koppa, Abigale; Henry, Amanda G; Leichliter, Jennifer N; Codron, Daryl; Codron, Jacqueline; Lambert, Joanna E; Sponheimer, Matt

    2018-04-01

    Discussions about early hominin diets have generally excluded grass leaves as a staple food resource, despite their ubiquity in most early hominin habitats. In particular, stable carbon isotope studies have shown a prevalent C 4 component in the diets of most taxa, and grass leaves are the single most abundant C 4 resource in African savannas. Grass leaves are typically portrayed as having little nutritional value (e.g., low in protein and high in fiber) for hominins lacking specialized digestive systems. It has also been argued that they present mechanical challenges (i.e., high toughness) for hominins with bunodont dentition. Here, we compare the nutritional and mechanical properties of grass leaves with the plants growing alongside them in African savanna habitats. We also compare grass leaves to the leaves consumed by other hominoids and demonstrate that many, though by no means all, compare favorably with the nutritional and mechanical properties of known primate foods. Our data reveal that grass leaves exhibit tremendous variation and suggest that future reconstructions of hominin dietary ecology take a more nuanced approach when considering grass leaves as a potential hominin dietary resource. Copyright © 2017. Published by Elsevier Ltd.

  12. Effect of graded levels of Saccharum officinarum as an additive to ...

    African Journals Online (AJOL)

    An experiment was conducted to evaluate the effect of graded levels of sugar cane (Saccharum officinarum) as an additive to Guinea grass (Panicum maximum) silage. A previously established guinea grass plot, totaling an area of 625m2 was cut back and fertilized with urea at the rate of 200 kgN/ha. The pasture was then ...

  13. Changes in Yield and Chemical Composition of Standing and ...

    African Journals Online (AJOL)

    The results of proximate analysis of five tropical forage species and two forms of conserved forage over sampling period of 147 days of the dry season are presented. Three plots of Panicum maximum (Guinea grass) one plot of Cynodon nlemfuensis (giant star grass) and one plot of Centrosema pubescens (centro) were ...

  14. Chemical composition and in vitro ruminal fermentation of selected ...

    African Journals Online (AJOL)

    Chemical composition and in vitro ruminal fermentation of selected grasses in the semiarid savannas of Swaziland. ... In the Simunye grazing area the most common species were B. insculpta, U. mosambicensis, Heteropogon contortus, Panicum deustum and P. maximum. For grasses harvested from Simunye, the most (p ...

  15. Silage quality, dry matter intake and digestibility by West African ...

    African Journals Online (AJOL)

    Silage quality, dry matter intake and digestibility by West African dwarf sheep of Guinea grass (Panicum maximum cv Ntchisi) harvested at 4 and 12 week. ... Grass mixtures were subjected to silage for 42 days. Quality and chemical composition of the silage was assessed. Silage was also fed to WAD sheep to determine the ...

  16. Intercroping effect of Canavalia Ensiformis on regrowth ability and in ...

    African Journals Online (AJOL)

    The effect of legume intercrop on regrowth ability and nutritive value via in vitro gas production of guinea grass was evaluated in a 2 x 2 factorial arrangement. Panicum maximum cv T 58 grass with Canavalia ensiformis intercrop was studied for six weeks. The tiller height, tiller numbers, regrowth percentage were recorded ...

  17. X meeting utenti GRASS e GFOSS

    Directory of Open Access Journals (Sweden)

    Francesco Marucci

    2009-03-01

    Full Text Available 10th meeting of GRASS & GFOSS users The 10th Italian Congress of GRASS GIS and Geospatial Free and Open Source Software (GFOSS was held on the26 and 27 Feb in Cagliari. Highlights included updates on major GFOSS projects (GRASS, QGIS, the presentation of new projects (SpatiaLite and the public release of a free 3D visualization application suitable for distribution over the internet (RATMAN. Many users and developers connected to forge new business relationships and share new ideas.

  18. X meeting utenti GRASS e GFOSS

    Directory of Open Access Journals (Sweden)

    Francesco Marucci

    2009-03-01

    Full Text Available 10th meeting of GRASS & GFOSS usersThe 10th Italian Congress of GRASS GIS and Geospatial Free and Open Source Software (GFOSS was held on the26 and 27 Feb in Cagliari. Highlights included updates on major GFOSS projects (GRASS, QGIS, the presentation of new projects (SpatiaLite and the public release of a free 3D visualization application suitable for distribution over the internet (RATMAN. Many users and developers connected to forge new business relationships and share new ideas.

  19. Perrenial Grasses for Sustainable European Protein Production

    DEFF Research Database (Denmark)

    Jørgensen, Uffe; Lærke, Poul Erik

    2016-01-01

    benefits, a reduction of nitrate leaching equivalent to 23,000 tonnes N annually was estimated. This is approximately the reduction required by the WFD for Denmark. Even though much more organic matter will be mobilized for biorefining, soil carbon levels are estimated to be largely unchanged...... production into grass production. Grasses and legumes have higher contents of protein with better quality (high lysine and methionine contents) than grain and seed crops. Thus, substituting imported soya bean protein with protein extracted from perennial grasses is an interesting option....

  20. Maximum Likelihood Fusion Model

    Science.gov (United States)

    2014-08-09

    Symposium of Robotics Re- search. Sienna, Italy: Springer, 2003. [12] D. Hall and J. Llinas, “An introduction to multisensor data fusion ,” Proceed- ings of...a data fusion approach for combining Gaussian metric models of an environment constructed by multiple agents that operate outside of a global... data fusion , hypothesis testing,maximum likelihood estimation, mobile robot navigation REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT

  1. Genome sequence analysis of the model grass Brachypodium distachyon: insights into grass genome evolution

    Energy Technology Data Exchange (ETDEWEB)

    Schulman, Al

    2009-08-09

    Three subfamilies of grasses, the Erhardtoideae (rice), the Panicoideae (maize, sorghum, sugar cane and millet), and the Pooideae (wheat, barley and cool season forage grasses) provide the basis of human nutrition and are poised to become major sources of renewable energy. Here we describe the complete genome sequence of the wild grass Brachypodium distachyon (Brachypodium), the first member of the Pooideae subfamily to be completely sequenced. Comparison of the Brachypodium, rice and sorghum genomes reveals a precise sequence- based history of genome evolution across a broad diversity of the grass family and identifies nested insertions of whole chromosomes into centromeric regions as a predominant mechanism driving chromosome evolution in the grasses. The relatively compact genome of Brachypodium is maintained by a balance of retroelement replication and loss. The complete genome sequence of Brachypodium, coupled to its exceptional promise as a model system for grass research, will support the development of new energy and food crops

  2. Grass survey of the Itremo Massif records endemic central highland ...

    African Journals Online (AJOL)

    Twenty species are endemic to the central highlands, and a further 1 4 species are restricted to Madagascar. Five ecological groups of grasses were identified in the Itremo Massif: shade species in gallery forests, open wet area species, fire grasses, anthropogenic disturbance associated grasses and rock-dwelling grasses.

  3. Efeito da altura do capim-Tanzânia diferido nas características da pastagem no período do inverno Sward characteristics of deferred tanzania grass under different height levels, in the winter time

    Directory of Open Access Journals (Sweden)

    Marcos Weber do Canto

    2001-07-01

    Full Text Available O estudo foi desenvolvido no Município de Astorga, PR, na Fazenda Nossa Senhora de Aparecida, com o objetivo de avaliar as características da pastagem e o acúmulo de forragem em capim-Tanzânia (Panicum maximum Jacq., diferido e após pastejado no período de 23/07 a 18/09/1999, sob diferentes níveis de altura de pasto. O delineamento experimental usado foi o inteiramente casualizado, com duas repetições. Os tratamentos foram quatro alturas de pasto: T1=20, T2=40, T3=60 e T4=80 cm. Entretanto, para a análise estatística, utilizaram-se as alturas reais de pasto mantidas nas unidades experimentais, sendo: T1R1 = 26,3, T1R2 = 24,6, T2R1 = 47,9, T2R2 = 42,5, T3R1 = 55,8, T3R2 = 61,7, T4R1 = 69,2 e T4R2 = 71,4 cm. Pode-se concluir que a altura de pasto aumenta de forma linear as massas de forragem e de colmos verdes. O acúmulo de forragem não foi afetado pelas diferentes alturas de pasto.The study was carried out in the county of Astorga, PR, Brazil, in the Nossa Senhora de Aparecida farm. The objective was to study the sward characteristics and forage accumulation of tanzania grass, deferred and after grazed from 07/23 to 09/18/1999, under different sward height levels. The experimental design was a completely randommized, with two replications. The treatments were four levels of sward height: T1=20, T2=40, T3=60 and T4=80 cm. However, the true sward height levels were used for analysis statistics; T1R1=26,3, T1R2=24,6, T2R1=47,9, T2R2=42,5, T3R1=55,8, T3R2=61,7, T4R1=69,2 e T4R2=71,4 cm. Results indicate that: forage mass and green culm mass increased of the positive linear way with increased of sward height. There was no effect of sward height levels on the forage accumulation.

  4. Underwater Grass Comeback Helps Chesapeake Bay

    Science.gov (United States)

    The fortified Susquehanna Flats, the largest bed of underwater grasses in the Chesapeake Bay, seems able to withstand a major weather punch. Its resilience is contributing to an overall increase in the Bay’s submerged aquatic vegetation.

  5. Karl Konrad Grass jumalainimeste uurijana / Alar Laats

    Index Scriptorium Estoniae

    Laats, Alar

    2006-01-01

    Karl Konrad Grass oli 19. sajandil Dorpati keiserliku ülikooli usuteaduskonna Uue Testamendi õppejõud, kes tegeles hobi korras idakristluse (vene sektid) uurimisega. Tema peateoseks on uurimus "Die russischen Sekten". Ettekanne konverentsil 15.-16. aprill 2005. a.

  6. Tree-grass interactions in savannas

    CSIR Research Space (South Africa)

    Scholes, RJ

    1997-01-01

    Full Text Available Savannas occur where trees and grasses interact to create a biome that is neither grassland nor forest. Woody and gramineous plants interact by many mechanisms, some negative (competition) and some positive (facilitation). The strength and sign...

  7. Pampas Grass - Orange Co. [ds351

    Data.gov (United States)

    California Department of Resources — This dataset provides the known distribution of pampas grass (Cortaderia selloana) in southern Orange County. The surveys were conducted from May to June, 2007 and...

  8. Elephant grass as forage for ruminant animals

    OpenAIRE

    Rusdy, Muhammad

    2016-01-01

    The shortage of feed, particularly during the dry season is one of the major factor limiting productivity of livestock in the tropics. Napier or elephant grass (Pennisetum purpureum Schum.) shows a great potential to alleviate the problem because it is drought resistant and has high dry matter yield potential. As an attempt to generate information useful for improving the utilization of the grass, its potential and limitation are described. Its chemical composition and nutritive value as rela...

  9. Maximum noise abatement trajectories.

    Science.gov (United States)

    Zeldin, S.; Speyer, J.

    1972-01-01

    Minimum noise annoyance trajectories for developing STOL operation procedures are obtained by modulating five control variables in two dimensions. The performance index is formulated such that it explicitly assigns the same relative importance to thrust as it does to distances between discrete listeners and the aircraft. However, using a steepest descent optimization program, results indicate that it is preferable to keep the thrusters at their maximum value to minimize the integrated annoyance rather than to reduce thrust which would lower the instantaneous annoyance. Thrust decreases below its bound only when the instantaneous noise at a listener is limited.

  10. Maximum entropy methods

    International Nuclear Information System (INIS)

    Ponman, T.J.

    1984-01-01

    For some years now two different expressions have been in use for maximum entropy image restoration and there has been some controversy over which one is appropriate for a given problem. Here two further entropies are presented and it is argued that there is no single correct algorithm. The properties of the four different methods are compared using simple 1D simulations with a view to showing how they can be used together to gain as much information as possible about the original object. (orig.)

  11. Herbaceous Legume Encroachment Reduces Grass Productivity and Density in Arid Rangelands.

    Directory of Open Access Journals (Sweden)

    Thomas C Wagner

    Full Text Available Worldwide savannas and arid grasslands are mainly used for livestock grazing, providing livelihood to over a billion people. While normally dominated by perennial C4 grasses, these rangelands are increasingly affected by the massive spread of native, mainly woody legumes. The consequences are often a repression of grass cover and productivity, leading to a reduced carrying capacity. While such encroachment by woody plants has been extensively researched, studies on similar processes involving herbaceous species are rare. We studied the impact of a sustained and massive spread of the native herbaceous legume Crotalaria podocarpa in Namibia's escarpment region on the locally dominant fodder grasses Stipagrostis ciliata and Stipagrostis uniplumis. We measured tussock densities, biomass production of individual tussocks and tussock dormancy state of Stipagrostis on ten 10 m x 10 m plots affected and ten similarly-sized plots unaffected by C. podocarpa over eight consecutive years and under different seasonal rainfalls and estimated the potential relative productivity of the land. We found the percentage of active Stipagrostis tussocks and the biomass production of individual tussocks to increase asymptotically with higher seasonal rainfall reaching a maximum around 300 mm while the land's relative productivity under average local rainfall conditions reached only 40% of its potential. Crotalaria podocarpa encroachment had no effect on the proportion of productive grass tussocks, but reduced he productivity of individual Stipagrostis tussocks by a third. This effect of C. podocarpa on grass productivity was immediate and direct and was not compensated for by above-average rainfall. Besides this immediate effect, over time, the density of grass tussocks declined by more than 50% in areas encroached by C. podocarpa further and lastingly reducing the lands carrying capacity. The effects of C. podocarpa on grass productivity hereby resemble those of woody

  12. Electricity-assisted production of caproic acid from grass.

    Science.gov (United States)

    Khor, Way Cern; Andersen, Stephen; Vervaeren, Han; Rabaey, Korneel

    2017-01-01

    Medium chain carboxylic acids, such as caproic acid, are conventionally produced from food materials. Caproic acid can be produced through fermentation by the reverse β-oxidation of lactic acid, generated from low value lignocellulosic biomass. In situ extraction of caproic acid can be achieved by membrane electrolysis coupled to the fermentation process, allowing recovery by phase separation. Grass was fermented to lactic acid in a leach-bed-type reactor, which was then further converted to caproic acid in a secondary fermenter. The lactic acid concentration was 9.36 ± 0.95 g L -1 over a 33-day semi-continuous operation, and converted to caproic acid at pH 5.5-6.2, with a concentration of 4.09 ± 0.54 g L -1 during stable production. The caproic acid product stream was extracted in its anionic form, concentrated and converted to caproic acid by membrane electrolysis, resulting in a >70 wt% purity solution. In a parallel test exploring the upper limits of production rate through cell retention, we achieved the highest reported caproic acid production rate to date from a lignocellulosic biomass (grass, via a coupled process), at 0.99 ± 0.02 g L -1  h -1 . The fermenting microbiome (mainly consisting of Clostridium IV and Lactobacillus ) was capable of producing a maximum caproic acid concentration of 10.92 ± 0.62 g L -1 at pH 5.5, at the border of maximum solubility of protonated caproic acid. Grass can be utilized as a substrate to produce caproic acid. The biological intermediary steps were enhanced by separating the steps to focus on the lactic acid intermediary. Notably, the pipeline was almost completely powered through electrical inputs, and thus could potentially be driven from sustainable energy without need for chemical input.Graphical abstractMicrobial and electrochemical production of lactic acid, caproic acid and decane from grass.

  13. Afforestation of degraded grass land

    Energy Technology Data Exchange (ETDEWEB)

    Basappa, B.

    1983-01-01

    The suitability of 11 species was tested for planting on degraded land at Kogilemane in Belur Taluk, Karnataka. The soil was alkaline with no humus, litter or topsoil. The original vegetation was grass with the stemless palm Phoenix acaulis, still present at 600 plants per acre. Seedlings 4-6 months old and raised in polythene bags were planted in pits in July 1981; Bambusa vulgaris was planted as 8-month-old cuttings. No fertilizer was applied. The most successful species after the first season was Acacia auriculiformis. Satisfactory survival and growth were also obtained with Cassia siamea, Peltoforum ferruginum, Leucaena leucocephala (although this was later heavily damaged by wild rabbits) and Toona ciliata. The bamboo survived well but there was no culm formation during the experiment. In 1982 only 3 of the species were tested: A. auriculiformis, L. leucocephala (because of its fast growth rate) and Casuarina equisetifolia (which performed badly in 1981 but is suited to alkaline soils). All 3 species performed satisfactorily.

  14. Genetic compatibility determines endophyte-grass combinations.

    Directory of Open Access Journals (Sweden)

    Kari Saikkonen

    Full Text Available Even highly mutually beneficial microbial-plant interactions, such as mycorrhizal- and rhizobial-plant exchanges, involve selfishness, cheating and power-struggles between the partners, which depending on prevailing selective pressures, lead to a continuum of interactions from antagonistic to mutualistic. Using manipulated grass-endophyte combinations in a five year common garden experiment, we show that grass genotypes and genetic mismatches constrain genetic combinations between the vertically (via host seeds transmitted endophytes and the out-crossing host, thereby reducing infections in established grass populations. Infections were lost in both grass tillers and seedlings in F(1 and F(2 generations, respectively. Experimental plants were collected as seeds from two different environments, i.e., meadows and nearby riverbanks. Endophyte-related benefits to the host included an increased number of inflorescences, but only in meadow plants and not until the last growing season of the experiment. Our results illustrate the importance of genetic host specificity and trans-generational maternal effects on the genetic structure of a host population, which act as destabilizing forces in endophyte-grass symbioses. We propose that (1 genetic mismatches may act as a buffering mechanism against highly competitive endophyte-grass genotype combinations threatening the biodiversity of grassland communities and (2 these mismatches should be acknowledged, particularly in breeding programmes aimed at harnessing systemic and heritable endophytes to improve the agriculturally valuable characteristics of cultivars.

  15. Madagascar's grasses and grasslands: anthropogenic or natural?

    Science.gov (United States)

    Besnard, Guillaume; Forest, Félix; Malakasi, Panagiota; Moat, Justin; Clayton, W. Derek; Ficinski, Paweł; Savva, George M.; Nanjarisoa, Olinirina P.; Razanatsoa, Jacqueline; Randriatsara, Fetra O.; Kimeu, John M.; Luke, W. R. Quentin; Kayombo, Canisius; Linder, H. Peter

    2016-01-01

    Grasses, by their high productivity even under very low pCO2, their ability to survive repeated burning and to tolerate long dry seasons, have transformed the terrestrial biomes in the Neogene and Quaternary. The expansion of grasslands at the cost of biodiverse forest biomes in Madagascar is often postulated as a consequence of the Holocene settlement of the island by humans. However, we show that the Malagasy grass flora has many indications of being ancient with a long local evolutionary history, much predating the Holocene arrival of humans. First, the level of endemism in the Madagascar grass flora is well above the global average for large islands. Second, a survey of many of the more diverse areas indicates that there is a very high spatial and ecological turnover in the grass flora, indicating a high degree of niche specialization. We also find some evidence that there are both recently disturbed and natural stable grasslands: phylogenetic community assembly indicates that recently severely disturbed grasslands are phylogenetically clustered, whereas more undisturbed grasslands tend to be phylogenetically more evenly distributed. From this evidence, it is likely that grass communities existed in Madagascar long before human arrival and so were determined by climate, natural grazing and other natural factors. Humans introduced zebu cattle farming and increased fire frequency, and may have triggered an expansion of the grasslands. Grasses probably played the same role in the modification of the Malagasy environments as elsewhere in the tropics. PMID:26791612

  16. The last glacial maximum

    Science.gov (United States)

    Clark, P.U.; Dyke, A.S.; Shakun, J.D.; Carlson, A.E.; Clark, J.; Wohlfarth, B.; Mitrovica, J.X.; Hostetler, S.W.; McCabe, A.M.

    2009-01-01

    We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ???14.5 ka.

  17. Treatment with grass allergen peptides improves symptoms of grass pollen-induced allergic rhinoconjunctivitis.

    Science.gov (United States)

    Ellis, Anne K; Frankish, Charles W; O'Hehir, Robyn E; Armstrong, Kristen; Steacy, Lisa; Larché, Mark; Hafner, Roderick P

    2017-08-01

    Synthetic peptide immunoregulatory epitopes are a new class of immunotherapy to treat allergic rhinoconjunctivitis (ARC). Grass allergen peptides, comprising 7 synthetic T-cell epitopes derived from Cyn d 1, Lol p 5, Dac g 5, Hol l 5, and Phl p 5, is investigated for treatment of grass pollen-induced ARC. We sought to evaluate the efficacy, safety, and tolerability of intradermally administered grass allergen peptides. A multicenter, randomized, double-blind, placebo-controlled study evaluated 3 regimens of grass allergen peptides versus placebo in patients with grass pollen-induced allergy (18-65 years). After a 4-day baseline challenge to rye grass in the environmental exposure unit (EEU), subjects were randomized to receive grass allergen peptides at 6 nmol at 2-week intervals for a total of 8 doses (8x6Q2W), grass allergen peptides at 12 nmol at 4-week intervals for a total of 4 doses (4x12Q4W), or grass allergen peptides at 12 nmol at 2-week intervals for a total of 8 doses (8x12Q2W) or placebo and treated before the grass pollen season. The primary efficacy end point was change from baseline in total rhinoconjunctivitis symptom score across days 2 to 4 of a 4-day posttreatment challenge (PTC) in the EEU after the grass pollen season. Secondary efficacy end points and safety were also assessed. Two hundred eighty-two subjects were randomized. Significantly greater improvement (reduction of total rhinoconjunctivitis symptom score from baseline to PTC) occurred across days 2 to 4 with grass allergen peptide 8x6Q2W versus placebo (-5.4 vs -3.8, respectively; P = .0346). Greater improvement at PTC also occurred for grass allergen peptide 8x6Q2W versus placebo (P = .0403) in patients with more symptomatic ARC. No safety signals were detected. Grass allergen peptide 8x6Q2W significantly improved ARC symptoms after rye grass allergen challenge in an EEU with an acceptable safety profile. Copyright © 2017 American Academy of Allergy, Asthma & Immunology

  18. Solar maximum observatory

    International Nuclear Information System (INIS)

    Rust, D.M.

    1984-01-01

    The successful retrieval and repair of the Solar Maximum Mission (SMM) satellite by Shuttle astronauts in April 1984 permitted continuance of solar flare observations that began in 1980. The SMM carries a soft X ray polychromator, gamma ray, UV and hard X ray imaging spectrometers, a coronagraph/polarimeter and particle counters. The data gathered thus far indicated that electrical potentials of 25 MeV develop in flares within 2 sec of onset. X ray data show that flares are composed of compressed magnetic loops that have come too close together. Other data have been taken on mass ejection, impacts of electron beams and conduction fronts with the chromosphere and changes in the solar radiant flux due to sunspots. 13 references

  19. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan

    2015-02-12

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  20. Different techniques to study rumen fermentation characteristics of maturing grass and grass silage

    NARCIS (Netherlands)

    Cone, J.W.; Gelder, van A.H.; Soliman, I.A.; Visser, de H.; Vuuren, van A.M.

    1999-01-01

    Grass samples were harvested during the 1993 growing season after a precut on April 27, 1993 and were stored frozen or left to ensile in 30-L buckets. Effects on chemical composition and fermentation kinetics of the maturation of the grass and of ensiling were investigated. Chemical composition and

  1. Ingestive Behavior of Ovine Fed with Marandu Grass Silage Added with Naturally Dehydrated Brewery Residue

    Directory of Open Access Journals (Sweden)

    Daniele de Jesus Ferreira

    2016-01-01

    Full Text Available The objective was to evaluate the ingestive behavior of ovine fed Marandu grass silage with dehydrated brewery residue added. The experiment had a completely randomized design with five treatments and four repetitions, with the treatments levels of inclusion being of 0, 10, 20, 30, and 40% natural matter of naturally dehydrated brewery residue for 36 hours to the marandu grass silage. 20 ovines were used and the experimental period was 21 days, 15 being for adaptation to diets. The use of brewery byproduct promoted quadratic effect (P<0.05 for the consumption of dry matter with maximum point value estimated at adding 23.25% additive. Ingestion efficiency and rumination efficiency of dry matter (g DM/hour were significant (P<0.05, by quadratic behavior, and NDF ingestion and rumination efficiency showed crescent linear behavior. The DM and NDF consumption expressed in kg/meal and in minutes/kg were also significant (P<0.05, showing quadratic behavior. Rumination activity expressed in g DM and NDF/piece was influenced (P<0.05 by the adding of brewery residue in marandu grass silage in quadratic way, with maximum value estimated of 1.57 g DM/bolus chewed in inclusion of 24.72% additive in grass silage. The conclusion is that intermediary levels adding of 20 to 25% dehydrated brewery residue affects certain parameters of ingestive behavior.

  2. Determinants of flammability in savanna grass species.

    Science.gov (United States)

    Simpson, Kimberley J; Ripley, Brad S; Christin, Pascal-Antoine; Belcher, Claire M; Lehmann, Caroline E R; Thomas, Gavin H; Osborne, Colin P

    2016-01-01

    Tropical grasses fuel the majority of fires on Earth. In fire-prone landscapes, enhanced flammability may be adaptive for grasses via the maintenance of an open canopy and an increase in spatiotemporal opportunities for recruitment and regeneration. In addition, by burning intensely but briefly, high flammability may protect resprouting buds from lethal temperatures. Despite these potential benefits of high flammability to fire-prone grasses, variation in flammability among grass species, and how trait differences underpin this variation, remains unknown.By burning leaves and plant parts, we experimentally determined how five plant traits (biomass quantity, biomass density, biomass moisture content, leaf surface-area-to-volume ratio and leaf effective heat of combustion) combined to determine the three components of flammability (ignitability, sustainability and combustibility) at the leaf and plant scales in 25 grass species of fire-prone South African grasslands at a time of peak fire occurrence. The influence of evolutionary history on flammability was assessed based on a phylogeny built here for the study species.Grass species differed significantly in all components of flammability. Accounting for evolutionary history helped to explain patterns in leaf-scale combustibility and sustainability. The five measured plant traits predicted components of flammability, particularly leaf ignitability and plant combustibility in which 70% and 58% of variation, respectively, could be explained by a combination of the traits. Total above-ground biomass was a key driver of combustibility and sustainability with high biomass species burning more intensely and for longer, and producing the highest predicted fire spread rates. Moisture content was the main influence on ignitability, where species with higher moisture contents took longer to ignite and once alight burnt at a slower rate. Biomass density, leaf surface-area-to-volume ratio and leaf effective heat of combustion

  3. Biogas from grass silage - Measurements and modeling with ADM1.

    Science.gov (United States)

    Koch, Konrad; Lübken, Manfred; Gehring, Tito; Wichern, Marc; Horn, Harald

    2010-11-01

    Mono fermentation of grass silage without the addition of manure was performed over a period of 345days under mesophilic conditions (38 degrees C). A simulation study based on the IWA Anaerobic Digestion Model No. 1 (ADM1) was done in order to show its applicability to lignocellulosic biomass. Therefore, the influent was fractioned by established fodder analysis (Weender analysis and van Soest method). ADM1 was modified with a separate compound of inert decay products similar to the approach of Activated Sludge Model No. 1 (ASM1). Furthermore, a function, which described the influence of solids on the process of hydrolysis, has been integrated to reproduce reliable ammonium concentrations. The model was calibrated by using the modified Nash-Sutcliffe coefficient to evaluate simulation quality. It was possible to fit observed data by changing only hydrogen inhibition constants and the maximum acetate uptake rate. The extended ADM1 model showed good agreement with measurements and was suitable for modeling anaerobic digestion of grass silage. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Development and validation of a 5-day-ahead hay fever forecast for patients with grass-pollen-induced allergic rhinitis

    Science.gov (United States)

    de Weger, Letty A.; Beerthuizen, Thijs; Hiemstra, Pieter S.; Sont, Jacob K.

    2014-08-01

    One-third of the Dutch population suffers from allergic rhinitis, including hay fever. In this study, a 5-day-ahead hay fever forecast was developed and validated for grass pollen allergic patients in the Netherlands. Using multiple regression analysis, a two-step pollen and hay fever symptom prediction model was developed using actual and forecasted weather parameters, grass pollen data and patient symptom diaries. Therefore, 80 patients with a grass pollen allergy rated the severity of their hay fever symptoms during the grass pollen season in 2007 and 2008. First, a grass pollen forecast model was developed using the following predictors: (1) daily means of grass pollen counts of the previous 10 years; (2) grass pollen counts of the previous 2-week period of the current year; and (3) maximum, minimum and mean temperature ( R 2 = 0.76). The second modeling step concerned the forecasting of hay fever symptom severity and included the following predictors: (1) forecasted grass pollen counts; (2) day number of the year; (3) moving average of the grass pollen counts of the previous 2 week-periods; and (4) maximum and mean temperatures ( R 2 = 0.81). Since the daily hay fever forecast is reported in three categories (low-, medium- and high symptom risk), we assessed the agreement between the observed and the 1- to 5-day-ahead predicted risk categories by kappa, which ranged from 65 % to 77 %. These results indicate that a model based on forecasted temperature and grass pollen counts performs well in predicting symptoms of hay fever up to 5 days ahead.

  5. Influência de variáveis químicas e estruturais do dossel sobre a taxa de ingestão instantânea em bovinos manejados em pastagens tropicais Influence of structural characteristics and chemical composition of tropical grasses on the instantaneous forage intake rate

    Directory of Open Access Journals (Sweden)

    Fabíola Cristine de Almeida Rego

    2006-06-01

    - altura capim-marandu, PBL - PB lâminas de capim-marandu.Steer forage intake rate (IR was evaluated in pastures of Brachiaria brizantha, Panicum maximum cv. Tanzania, Arachis pintoi and a mixed of Brachiaria brizantha with Arachis pintoi. The objectives were to define sward structural characteristics and chemical composition nutrients of each pasture most determinant of forage intake rate by grazing steers. The steers grazed in pairs, passing through all grass species maintained at different sward heights in successive days. After three hours fast the animals were allowed to graze each experimental area for 60 minutes and had their grazing time and bite numbers registered. Forage intake was estimated by the double sampling technique. Sward structural characteristics used in the model for estimation of IR were: average sward height, morphological component proportion (%, morphological component mass (ton DM/ha and density of morphological components (kg DM/ha/cm. The chemical composition was expressed as crude protein (CP and neutral detergent fiber (NDF. Sward variables were selected using the stepwise statistical procedure. The IR equations defined from the studied characteristics were: Marandu grass: IR = 59,8980 + 0,7299 GL + 3,5777 DMA - 1,2459 NDFL + 0,2882 SH (GL - proportion of green leaves, FM - forage mass, NDFL - NDF of leaves, SH - average sward height. Tanzania grass: IR = 111,762 -4,1532 CPL + 0,3469 GL - 0,5207 NDFL (CP of leaves, GL - proportion of green leaves, NDFL - NDF of leaves. Peanut forage: IR = -196,589 + 12,1978 CPS + 8,3406 DMA + 1,1060 GS +17,3669 GLA (CPS - stem CP, DMA - dry matter availability, GLA - green leaves availability. Mixed pasture: IR= -7,25 + 1,15HA -0,22HI + 18,49AA -9,88GLA + 0,49HM + 1,00CPL (HA - Peanut forage height, HI - weed species height, AA - Arachis availability, GLA - green leaf availability of Marandu grass, HB - marandugrass sward height, CPL - CP of leaves of marandugrass.

  6. Role of carbohydrate metabolism in grass tetany

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.K.; Madsen, F.C.; Lentz, D.E.; Hansard, S.L.

    1977-01-01

    Clinical hypomagnesemia is confined primarily to beef cattle in the United States but also occurs in dairy cattle in other countries, probably due to different management practices. During periods when grass tetany is likely, early vegetative temperate zone grasses are usually low in total readily available carbohydrates and magnesium but high in potassium and nitrogen. The tetany syndrome may include hypoglycemia and ketosis, suggesting an imbalance in intermediary energy metabolism. Many enzyme systems critical to cellular metabolism, including those which hydrolyze and transfer phosphate groups, are activated by Mg. Thus, by inference, Mg is required for normal glucose utilization, fat, protein, nucleic acid and coenzyme synthesis, muscle contraction, methyl group transfer, and sulfate, acetate, and formate activation. Numerous clinical and experimental studies suggest an intimate relationship between metabolism of Mg and that of carbohydrate, glucagon, and insulin. The objective is to review this literature and suggest ways in which these relationships might contribute to a chain of events leading to grass tetany.

  7. Grass Biomethane for Agriculture and Energy

    DEFF Research Database (Denmark)

    Korres, N.E.; Thamsiriroj, T.; Smith, B.

    2011-01-01

    Many factors enforce the intensification of grassland utilization which is associated with significant environmental impacts subjected to various legislative constraints. Nevertheless, the need for diversification in agricultural production and the sustainability in energy within the European Union...... have advanced the role of grassland as a renewable source of energy in grass biomethane production with various environmental and socio-economic benefits. It is underlined that the essential question whether the gaseous biofuel meets the EU sustainability criteria of 60% greenhouse gas emission savings...... by 2020 can be met since savings up to 89.4% under various scenarios can be achieved. Grass biomethane production compared to other liquid biofuels either when these are produced by indigenous of imported feedstocks is very promising. Grass biomethane, given the mature and well known technology...

  8. Grass pollen immunotherapy: where are we now.

    Science.gov (United States)

    Würtzen, Peter A; Gupta, Shashank; Brand, Stephanie; Andersen, Peter S

    2016-01-01

    During allergen immunotherapy (AIT), the allergic patient is exposed to the disease-inducing antigens (allergens) in order to induce clinical and immunological tolerance and obtain disease modification. Large trials of grass AIT with highly standardized subcutaneous and sublingual tablet vaccines have been conducted to document the clinical effect. Induction of blocking antibodies as well as changes in the balance between T-cell phenotypes, including induction of regulatory T-cell subtypes, have been demonstrated for both treatment types. These observations increase the understanding of the immunological mechanism behind the clinical effect and may make it possible to use the immunological changes as biomarkers of clinical effect. The current review describes the recent mechanistic findings for subcutaneous immunotherapy and sublingual immunotherapy/tablet treatment and discusses how the observed immunological changes translate into a scientific foundation for the observed clinical effects of grass pollen immunotherapy and lead to new treatment strategies for grass AIT.

  9. Biogas and Methane Yield from Rye Grass

    Directory of Open Access Journals (Sweden)

    Tomáš Vítěz

    2015-01-01

    Full Text Available Biogas production in the Czech Republic has expanded substantially, including marginal regions for maize cultivation. Therefore, there are increasingly sought materials that could partially replace maize silage, as a basic feedstock, while secure both biogas production and its quality.Two samples of rye grass (Lolium multiflorum var. westerwoldicum silage with different solids content 21% and 15% were measured for biogas and methane yield. Rye grass silage with solid content of 15% reached an average specific biogas yield 0.431 m3·kg−1 of organic dry matter and an average specific methane yield 0.249 m3·kg−1 of organic dry matter. Rye grass silage with solid content 21% reached an average specific biogas yield 0.654 m3·kg−1 of organic dry matter and an average specific methane yield 0.399 m3·kg−1 of organic dry matter.

  10. Índices morfogênicos e de crescimento durante o estabelecimento e a rebrotação do capim-Mombaça (Panicum maximum Jacq. Morphogenic traits and growth indices during the establishment and regrowth of Mombaçagrass (Panicum maximum Jacq.

    Directory of Open Access Journals (Sweden)

    Carlos Augusto de Miranda Gomide

    2003-08-01

    Full Text Available Com o objetivo de estimar as características morfogênicas e os índices de crescimento do capim-Mombaça, um ensaio foi conduzido em casa de vegetação. Estudou-se o desenvolvimento das plantas em três crescimentos: o crescimento seminal de estabelecimento (C1, o da brotação após corte ao 16º dia (C2 e 37º dia (C3 do crescimento de estabelecimento. As variáveis estimadas foram: índices de crescimento [taxa de crescimento relativo (TCR, taxa assimilatória líquida (TAL e razão de área foliar (RAF], e os índices morfogênicos [taxa de aparecimento foliar (TApF, taxa de alongamento foliar (TAlF, taxa de expansão da área foliar e taxa de senescência foliar]. Colheitas foram feitas ao longo do desenvolvimento das plantas em cada crescimento considerado: 13, 20, 27, 42, 55, 69 e 83 dias após emergência (C1; 0, 3, 6, 10, 17, 24, 38, 52 e 66 dias após o corte aos 16 dias (C2 e 0, 1, 3, 7, 21, 35, 49, 63 e 77 dias após o corte aos 37 dias (C3. Foram observadas três repetições (vasos, segundo delineamento inteiramente casualizado. Altos valores de TAL, RAF e TCR foram observados no início do crescimento seminal (C1 das plantas, caindo assintoticamente com o avanço da idade. O corte aos 37 dias de idade comprometeu o crescimento das plantas expresso em seus valores de TApF, a TAlF e a taxa de expansão da área foliar, RAF, TAL e TCR, sendo observados valores negativos para estes dois últimos índices, nos primeiros dias de brotação. A baixa demanda respiratória e a alocação de fotoassimilados para o crescimento foliar garantiram às plantas cortadas aos 16 dias, balanço positivo de carbono, possibilitando sua rápida recuperação.A trial was carried out in green-house to estimate morphogenic traits and growth indices of Mombaçagrass development. Three growths were considered: the seminal, establishment growth (G1 and the regrowths following a clipping taken on the 16th (G2 and 37th (G3 days of the seminal growth. The variables assessed were the growth indices: relative growth rate (RGR, net assimilation rate (NAR, leaf area ratio (LAR, and the rates of leaf appearance, elongation, expansion and senescence. Accordingly, harvests were taken at the ages of: 13, 20, 27, 42, 55, 69 and 83 day of the seminal growth (G1; 0, 3, 6, 10, 17, 24, 38, 52 and 66 day of the 2nd regrowth (G2 and 0, 1, 3, 7, 21, 35, 49, 63 and 77 day of the 3rd growth (G3. There were three replications (pots per treatment in a completely randomized design. Figures for NAR, LAR and RGR were high during early seminal growth but declined assynthotically as plant aged. Initial values for these indices were higher in the seminal growth as compared to the 2 regrowths. Cutting taken on the 37th day of the seminal growth hindered the initial growth of the plants regarding leaf appearance and elongation rates, LAR, NAR and RGR. The latter two indices which had negative values during early regrowth, were recovered by the 16th regrowth day.

  11. Duração do período de descanso e crescimento do dossel de Panicum maximum cv. Mombaça sob lotação intermitente Duration of rest period and canopy growth of Panicum maximum cv. Mombaça under intermittent stocking

    Directory of Open Access Journals (Sweden)

    Magno José Duarte Cândido

    2005-04-01

    Full Text Available O crescimento do dossel do capim-Mombaça foi analisado sob lotação intermitente com três períodos de descanso (PD, tratamentos definidos em função do tempo necessário para a expansão de 2,5; 3,5 e 4,5 novas folhas por perfilho e período de pastejo de seis dias. A área experimental foi dividida em cinco ou seis piquetes por tratamento. Utilizaram-se cinco novilhos mestiços (holandês x zebu por tratamento, como animais de prova, além de outros, como animais de equilíbrio, que foram adicionados, quando necessário, para garantir índice de área foliar (IAF residual de 2,0, ao final do 6(0 dia de cada período de pastejo. O estudo constou de duas fases de crescimento: 1 após roçada de uniformização, no início da estação de pastejo e 2 após alguns ciclos de pastejo, sob efeito dos três PDs. Os piquetes receberam adubação em cobertura de N, P2O5 e K2O, na dose de 50; 12,5 e 50 kg/ha, no início dos crescimentos 1 e 2. A intervalo médio de seis dias, durante 45 dias, estimaram-se a intercepção da radiação fotossinteticamente ativa (RFA, o IAF e a massa seca de forragem verde (MSFV. Aos dados de MSFV e de área foliar foram ajustados polinômios de segundo grau em função da idade, a partir dos quais foram estimados os valores instantâneos de biomassa e IAF e, a partir destes, as taxas de crescimento relativo (TCR e de assimilação líquida (TAL e a razão de área foliar (RAF, para cada idade. A intercepção da RFA pelo dossel evoluiu assintoticamente, alcançando valores máximos entre 95 e 98%, enquanto os valores de IAF e MSFV experimentaram incrementos ainda na faixa de estabilidade da intercepção da RFA. Os valores de TCR, TAL e RAF exibiram evolução assintótica decrescente. A grande proporção de colmo do dossel, ao final do PD mais longo, favoreceu a TCR e a TAL.The canopy growth of Mombaçagrass was assessed under intermittent stocking with three rest periods, characterized by the time required for the expansion of 2.5, 3.5, and 4.5 new leaf blades per tiller, after grazing periods of six days. The experimental area was divided into five or six paddocks per treatment. Five crossbreed (Holstein x Zebu steers were randomly assigned to each treatment. Extra steers were also used to achieve residual leaf area index of about 2.0, by the end of each grazing period. Two Growth phases were considered: 1 after standardization cut at the beginning of the growing season, and 2 after some grazing cycles had taken place, under the effects of the experimental rest periods. The paddocks received broadcast fertilization of N, P2O5 and K2O (50, 12.5 and 50 kg/ha in the beginning of the growth phases 1 and 2. Photo synthetically active radiation (PAR interception, leaf area index (LAI and green forage dry mass (GFDM were assessed over 45 days of regrowth, at six day intervals. Second order polynomials were adjusted to GFDM and LAI data, as a function of canopy ages. From these equations, instantaneous values of GFDM and LAI were estimated, from which it was derived the instantaneous values of relative growth rate (RGR and net assimilation rate (NAR, respectively for each canopy age. PAR interception by the canopy increased in an asymptotic manner, reaching critical values of 95 - 98%, while LAI and GFDM values increased in the stability range of PAR interception. The growth indices RGR, NAR and LAR showed decreasing asymptotic evolution. The great proportion of stem in end of the longest rest period favored the decrease in RGR and NAR values.

  12. Biogas production from anaerobic codigestion of cowdung and elephant grass (Pennisetum Purpureum) using batch digester

    Science.gov (United States)

    Haryanto, Agus; Hasanudin, Udin; Afrian, Chandra; Zulkarnaen, Iskandar

    2018-03-01

    This study aimed at determining biogas production from codigestion of Elephant grass and cowdung using batch digester. Fresh grass was manually chopped with a maximum length of 3 cm. Chopped grass (25 kg) was perfectly mixed with fresh cowdung (25 kg). The mixture was introduced into a 220-liter batch drum digester. The substrate was diluted with water at different rates (P1 = 50 L, P2 = 75 L, and P3 = 100 L) and was stirred thoroughly. Six digesters were prepared as duplicate for each treatment. Two other digesters containing only 25 kg cowdung diluted with 25 L water were also provided as control treatment (P0). The digesters were air tightly sealed for 70 days. Observation was conducted on daily temperature, substrate pH (initial and final), TS and VS content, biogas yield and biogas composition. Results showed that final pH of grass containing substrate was in the acidic range, namely 4.50, 4.62, 6.82, whereas that of control (P0) was normal with pH of 7.30. Digester with substrate composition 25:25:100 (cowdung:grass:water) produced the highest biogas total (524.3 L). Biogas yield of codigestion, however, was much lower as compared to that of control, namely 7.35, 16.75, and 111.72 L/kg VS r respectively for treatment P1, P2, P3. with dilution rate of 50, 75, and 100 L. Biogas produced from control digester had methane content of 53.88%. In contrast, biogas resulted from all treatments contained low methane (the highest was 31.37%). Methane yield of 39.3 L/kg TS removal was achieved from digester with dilution 100 L (P3). Mechanical pretreatment is suggested to break Elephant grass down into smaller particles prior to introducing it into the digestion process.

  13. Cesium-137 in grass from Chernobyl fallout

    International Nuclear Information System (INIS)

    Papastefanou, C.; Manolopoulou, M.; Stoulos, S.; Ioannidou, A.; Gerasopoulos, E.

    2005-01-01

    Grass ecosystem was monitored for 137 Cs, a relatively long-lived radionuclide, for about 16 years since the Chernobyl reactor accident occurred on April 26, 1986. Cesium-137 in grass gramineae or poaceae the species, ranged from 122.9 Bq kg -1 (September 4, 1986) to 5.8 mBq kg -1 (October 16, 2001) that is a range of five orders of magnitude. It was observed that there was a trend of decreasing 137 Cs with time reflecting a removal half-time of 40 months (3 1/3 years), which is the ecological half-life, T ec of 137 Cs in grassland

  14. Clover-grass as an energy crop

    International Nuclear Information System (INIS)

    1996-11-01

    Breeding of clover grass on fallow areas as a resource for methane generation has several important advantages. It does not require any additional nitrogen fertilizer as it can fix the atmospheric nitrogen.Herbicides are unnecessary as most weeds are one-year plants, while clover is perennial. From methane generation data for clover-grass the gross energy generation has been calculated to 11.08 MJ per kg dry matter. Net energy generation (with account for electric power) is calculated to 14.00 MJ/kg dry matter. (EG)

  15. Distinct physiological responses underlie defoliation tolerance in African lawn and bunch grasses

    NARCIS (Netherlands)

    Anderson, T.M.; Kumordzi, B.B.; Fokkema, W.; Valls Fox, H.; Olff, H.

    Premise of research. African grass communities are dominated by two distinct functional types: tall, caespitose bunch grasses and short, spreading lawn grasses. Functional type coexistence has been explained by differences in defoliation tolerance, because lawn grasses occur in intensively grazed

  16. Identification and characterization of microRNAs and their targets in the bioenergy plant switchgrass (Panicum virgatum).

    Science.gov (United States)

    Xie, Fuliang; Frazier, Taylor P; Zhang, Baohong

    2010-07-01

    MicroRNAs (miRNAs) are a class of non-coding small endogenous RNAs with lengths of approximately 22 nucleotides (nt) that have been shown to regulate gene expression at the post-transcriptional levels by targeting mRNAs for degradation or by inhibiting protein translation. Although thousands of miRNAs have been identified in many species, miRNAs have not yet been identified in switchgrass (Panicum virgatum), one of the most important bioenergy crops in the United States and around the world. In this study, we identified 121 potential switchgrass miRNAs, belonging to 44 families, using a well-defined comparative genome-based computational approach. We also identified miRNA clusters and antisense miRNAs in switchgrass expressed sequences tags. These identified miRNAs potentially target 839 protein-coding genes, which can act as transcription factors, and take part in multiple biological and metabolic processes including sucrose and fat metabolism, signal transduction, stress response, and plant development. Gene ontology (GO) analysis, based on these targets, showed that 527 biological processes were involved. Twenty-five of these processes were demonstrated to participate in the metabolism of carbon, glucose, starch, fatty acid, and lignin and in xylem formation. According to pathway enrichment analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG), 118 metabolism networks were found. These networks are involved in sucrose metabolism, fat metabolism, carbon fixation, hormone regulation, oxidative stress response, and the processing of other secondary metabolites.

  17. Understanding changes in lignin of Panicum virgatum and Eucalyptus globulus as a function of ionic liquid pretreatment.

    Science.gov (United States)

    Varanasi, Patanjali; Singh, Priyanka; Arora, Rohit; Adams, Paul D; Auer, Manfred; Simmons, Blake A; Singh, Seema

    2012-12-01

    Ionic liquids (ILs) have shown great potential for the reduction of lignin in biomass after pretreatment. Although dilute acid and base pretreatments have been shown to result in pretreated biomass with substantially different lignin composition, there is scarce information on the composition of lignin of IL pretreated biomass. In this work, temperature dependent compositional changes in lignin after IL pretreatment were studied to develop a mechanistic understanding of the process. Panicum virgatum and Eucalyptus globulus were pretreated with 1-ethyl-3-methylimidazolium acetate ([C(2)mim][OAc]). Measurement of syringyl and guaiacyl ratio using pyrolysis-GC/MS and Kamlet-Taft properties of [C(2)mim][OAc] at 120 °C and 160 °C strongly suggest two different modes of IL pretreatment. Preferential breakdown of S-lignin in both eucalyptus and switchgrass at high pretreatment temperature (160 °C) and breakdown of G-lignin for eucalyptus and no preferential break down of either S- or G-lignin in switchgrass was observed at lower pretreatment temperatures (120 °C). Copyright © 2012. Published by Elsevier Ltd.

  18. Allelopathic Potential of Switchgrass ( Panicum virgatum L.) on Perennial Ryegrass ( Lolium perenne L.) and Alfalfa ( Medicago sativa L.)

    Science.gov (United States)

    Shui, Junfeng; An, Yu; Ma, Yongqing; Ichizen, Nobumasa

    2010-10-01

    This study investigated allelopathy and its chemical basis in nine switchgrass ( Panicum virgatum L.) accessions. Perennial ryegrass ( Lolium perenne L.) and alfalfa ( Medicago sativa L.) were used as test species. Undiluted aqueous extracts (5 g plant tissue in 50 ml water) from the shoots and roots of most of the switchgrass accessions inhibited the germination and growth of the test species. However, the allelopathic effect of switchgrass declined when extracts were diluted 5- or 50-fold. Seedling growth was more sensitive than seed germination as an indicator of allelopathic effect. Allelopathic effect was related to switchgrass ecotype but not related to ploidy level. Upland accessions displayed stronger allelopathic potential than lowland accessions. The aqueous extract from one switchgrass accession was separated into phenols, organic acids, neutral chemicals, and alkaloids, and then these fractions were bioassayed to test for allelopathic potential. Alkaloids had the strongest allelopathic effect among the four chemical fractions. In summary, the results indicated that switchgrass has allelopathic potential; however, there is not enough evidence to conclude that allelopathic advantage is the main factor that has contributed to the successful establishment of switchgrass on China’s Loess Plateau.

  19. Genetic Diversity and Population Structure of Broomcorn Millet (Panicum miliaceum L.) Cultivars and Landraces in China Based on Microsatellite Markers

    Science.gov (United States)

    Liu, Minxuan; Xu, Yue; He, Jihong; Zhang, Shuang; Wang, Yinyue; Lu, Ping

    2016-01-01

    Broomcorn millet (Panicum miliaceum L.), one of the first domesticated crops, has been grown in Northern China for at least 10,000 years. The species is presently a minor crop, and evaluation of its genetic diversity has been very limited. In this study, we analyzed the genetic diversity of 88 accessions of broomcorn millet collected from various provinces of China. Amplification with 67 simple sequence repeat (SSR) primers revealed moderate levels of diversity in the investigated accessions. A total of 179 alleles were detected, with an average of 2.7 alleles per locus. Polymorphism information content and expected heterozygosity ranged from 0.043 to 0.729 (mean = 0.376) and 0.045 to 0.771 (mean = 0.445), respectively. Cluster analysis based on the unweighted pair group method of mathematical averages separated the 88 accessions into four groups at a genetic similarity level of 0.633. A genetic structure assay indicated a close correlation between geographical regions and genetic diversity. The uncovered information will be valuable for defining gene pools and developing breeding programs for broomcorn millet. Furthermore, the millet-specific SSR markers developed in this study should serve as useful tools for assessment of genetic diversity and elucidation of population structure in broomcorn millet. PMID:26985894

  20. DINAMICA POBLACIONAL DE Panicum polygonatum Y Axonopus micay BAJO COMBATE CON HERBICIDAS Y CHAPEA, EN UNA PLANTACIÓN BANANERA

    Directory of Open Access Journals (Sweden)

    Ana Mar\\u00EDa Rodr\\u00EDguez-Ruiz

    2011-01-01

    Full Text Available El objetivo de esta investigación fue determinar los cambios poblacionales de arvenses poáceas bajo combate químico y de chapea . El trabajo se realizó en una finca bananera en la zona de Cariari de Pococí, entre octubre del 2003 a setiembre 2005. Se estableció un experimento con un diseño de bloques al azar, con cuatro tratamie ntos: chapea s bimensuales, aplicaciones calendarizadas con glifosato, aplicaciones calendarizadas con glufosinato y tratamie nto monitoreado aplicado con base al monitoreo de las arvenses presentes. Las principa les poáceas registradas fueron Panicum polygonatum y Axonopus micay. Se realizaron recuentos de las arvenses cada dos meses. A partir de la segunda evaluación el glifosato tendió a disminuir de manera significativa las poblaciones de P. polygonatum, en tanto que la chapea favoreció el desarrollo de la misma; con los tratamie ntos de glufosinato y el monitoreado las poblaciones de la maleza se mantuvie ron intermedia s. Los tratamie ntos de glufosinato y la chapea aumentaron las poblaciones de A. micay.

  1. Using the Model Perennial Grass Brachypodium sylvaticum to Engineer Resistance to Multiple Abiotic Stresses

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Sean; Reguera, Maria; Sade, Nir; Cartwright, Amy; Tobias, Christian; Thilmony, Roger; Blumwald, Eduardo; Vogel, John

    2015-03-20

    We are using the perennial model grass Brachypodium sylvaticum to identify combinations of transgenes that enhance tolerance to multiple, simultaneous abiotic stresses. The most successful transgene combinations will ultimately be used to create improved switchgrass (Panicum virgatum L.) cultivars. To further develop B. sylvaticum as a perennial model grass, and facilitate our planned transcriptional profiling, we are sequencing and annotating the genome. We have generated ~40x genome coverage using PacBio sequencing of the largest possible size selected libraries (18, 22, 25 kb). Our initial assembly using only long-read sequence contained 320 Mb of sequence with an N50 contig length of 315 kb and an N95 contig length of 40 kb. This assembly consists of 2,430 contigs, the largest of which was 1.6 Mb. The estimated genome size based on c-values is 340 Mb indicating that about 20 Mb of presumably repetitive DNA remains yet unassembled. Significantly, this assembly is far superior to an assembly created from paired-end short-read sequence, ~100x genome coverage. The short-read-only assembly contained only 226 Mb of sequence in 19k contigs. To aid the assembly of the scaffolds into chromosome-scale assemblies we produced an F2 mapping population and have genotyped 480 individuals using a genotype by sequence approach. One of the reasons for using B. sylvaticum as a model system is to determine if the transgenes adversely affect perenniality and winter hardiness. Toward this goal, we examined the freezing tolerance of wild type B. sylvaticum lines to determine the optimal conditions for testing the freezing tolerance of the transgenics. A survey of seven accessions noted significant natural variation in freezing tolerance. Seedling or adult Ain-1 plants, the line used for transformation, survived an 8 hour challenge down to -6 oC and 50% survived a challenge down to -9 oC. Thus, we will be able to easily determine if the transgenes compromise freezing tolerance. In the

  2. Names of Southern African grasses: Name changes and additional ...

    African Journals Online (AJOL)

    The main reasons for changes in botanical names are briefly reviewed, with examples from the lists. At this time, about 1040 grass species and subspecific taxa are recognized in the subcontinent. Keywords: botanical research; botanical research institute; botany; grass; grasses; identification; name change; nomenclature; ...

  3. Germination of Themeda triandra (Kangaroo grass) as affected by ...

    African Journals Online (AJOL)

    Low rainfall in range areas restricts germination, growth and development of majority of range grasses. However, germination and establishment potential of forage grasses vary and depends on environmental conditions. Themeda triandra is an excellent known grass to grow under different environmental conditions.

  4. A new grass frog from Namibia

    African Journals Online (AJOL)

    A new species of grass frog of the genus Ptychadena is described from northern Namibia. Although superficially similar to Ptychadena schilJukorum and Ptychadsna mossambica. the new species differs In advenisemen1 call, and erlernal charaders. An examination of a series of published sonagrams indicates.

  5. Grass Pollen Pollution from Biofuels Farming

    Czech Academy of Sciences Publication Activity Database

    Ratajová, A.; Tříska, Jan; Vrchotová, Naděžda; Kolář, L.; Kužel, S.

    2013-01-01

    Roč. 26, č. 4 (2013), s. 199-203 ISSN 2151-321X R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : grass pollen pollution * biofuel s farming * temperate climate * PK-fertilization * N-fertilization * phenolic Subject RIV: EH - Ecology, Behaviour Impact factor: 0.556, year: 2013

  6. Notes on Alien Bromus Grasses in Taiwan

    Directory of Open Access Journals (Sweden)

    Ming-Jer Jung

    2006-06-01

    Full Text Available Bromus carinatus Hook. & Arn., Bromus hordeaceus L., Bromus pubescens Muhl. ex Willd. and Bromus secalinus L. were recently found at middle elevations of southern and central Taiwan, respectively. We present taxonomic treatments, distribution map, and line-drawings of these introduced alien brome grasses.

  7. MoDest GrassUp

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Nyholm; S. Nadimi, Esmaeil

    2010-01-01

    The Technology The technology is one of a kind, as there is no such mathematical model estimating animal feed uptake available today. The estimation of grass uptake, is based on real time wireless sensor data, cow merit and climate data. Relevant cow behaviour data (such as location, movement vel...

  8. Grass Biomethane for Agriculture and Energy

    DEFF Research Database (Denmark)

    Korres, N.E.; Thamsiriroj, T.; Smith, B.

    2011-01-01

    have advanced the role of grassland as a renewable source of energy in grass biomethane production with various environmental and socio-economic benefits. It is underlined that the essential question whether the gaseous biofuel meets the EU sustainability criteria of 60% greenhouse gas emission savings...

  9. Extraction of Spear Grass (Imperata Cylindrica As Pro-Oxidant In Polymer Blends

    Directory of Open Access Journals (Sweden)

    Nuradibah M.A.

    2018-01-01

    Full Text Available Packaging material such as plastic bags is one of the main factors that contribute to the environmental pollution due to slow degradation. The usage of metal oxide as pro-oxidant has been proven to accelerate the degradation of these materials, but the excessive usage of this pro-oxidant will be harmful to the human body. Therefore, in this research, spear grass is investigated to be used as natural based pro-oxidant that can increase the degradation rate of the polymers. In terms of that, spear grass is extracted by using pressurized hot water extraction (PHWE to obtain the metal element such as zinc (Zn and ferum (Fe. PHWE is using water as a solvent which is highly favourable due to non-toxicity and non-flammable characteristics that make it easy to handle. Box-Behnken design is used to optimize the temperature, extraction time, and sample-to-solvent ratio to get the maximum amount of Zn and Fe concentration from the extracted spear grass. As a conclusion, the leaf of spear grass contributed the highest amount of Zn and Fe concentration. The highest amount of Zn and Fe concentration is achieved at 150 °C, 20 minutes, and 3 g of sample to 45 ml of water.

  10. Comparison of the fermentation quality and nutritive value of silage ...

    African Journals Online (AJOL)

    About 10-month-old leucaena (Leucaena leucocephala (Lam.) De Wit.) grown in Japan and 52-day-old regrowth of guinea grass (Panicum maximum var. maximum cv. Gatton) and sorghum (Sorghum bicolor Moench cv. FS40IR), were chopped up to 3-5 cm lengths and ensiled in laboratory silos of 1.4-1.5 kg capacity.

  11. Perennial grasses for recovery of the aggregation capacity of a reconstructed soil in a coal mining area in southern Brazil

    Directory of Open Access Journals (Sweden)

    Lizete Stumpf

    2014-02-01

    Full Text Available The construction of a soil after surface coal mining involves heavy machinery traffic during the topographic regeneration of the area, resulting in compaction of the relocated soil layers. This leads to problems with water infiltration and redistribution along the new profile, causing water erosion and consequently hampering the revegetation of the reconstructed soil. The planting of species useful in the process of soil decompaction is a promising strategy for the recovery of the soil structural quality. This study investigated the influence of different perennial grasses on the recovery of reconstructed soil aggregation in a coal mining area of the Companhia Riograndense de Mineração, located in Candiota-RS, which were planted in September/October 2007. The treatments consisted of planting: T1- Cynodon dactylon cv vaquero; T2 - Urochloa brizantha; T3 - Panicum maximun; T4 - Urochloa humidicola; T5 - Hemarthria altissima; T6 - Cynodon dactylon cv tifton 85. Bare reconstructed soil, adjacent to the experimental area, was used as control treatment (T7 and natural soil adjacent to the mining area covered with native vegetation was used as reference area (T8. Disturbed and undisturbed soil samples were collected in October/2009 (layers 0.00-0.05 and 0.10-0.15 m to determine the percentage of macro- and microaggregates, mean weight diameter (MWD of aggregates, organic matter content, bulk density, and macro- and microporosity. The lower values of macroaggregates and MWD in the surface than in the subsurface layer of the reconstructed soil resulted from the high degree of compaction caused by the traffic of heavy machinery on the clay material. After 24 months, all experimental grass treatments showed improvements in soil aggregation compared to the bare reconstructed soil (control, mainly in the 0.00-0.05 m layer, particularly in the two Urochloa treatments (T2 and T4 and Hemarthria altissima (T5. However, the great differences between the

  12. Abundance and diaspore weight in rare and common prairie grasses.

    Science.gov (United States)

    Rabinowitz, Deborah

    1978-01-01

    Abundance (g/m 2 ) and diaspore weight are positively correlated in seven species of perennial grasses that occur in prairies. The rare grasses (10.0 g/m 2 ) have heavy dispersal units (2.23 to 2.80 mg). This result is the first reported differentiating trait between related rare and common organisms occurring in same habitat.Three hypotheses that explain this phenomenon are compared; the third most likely holds. First, rare grasses may be rare because their small seeds are less successful in establishment than those of common grasses. Second, if the persistence of small populations is marginal, rare grasses may devote less energy (or other currency) to seed production. Third, rare grasses may be colonizers of spatially and temporally rare microsites appropriate for growth and thus have seeds adapted for longer distance dispersal than those of common grasses. This last hypothesis suggests a new pathway for the evolution of weeds.

  13. Nowcasting daily minimum air and grass temperature

    Science.gov (United States)

    Savage, M. J.

    2016-02-01

    Site-specific and accurate prediction of daily minimum air and grass temperatures, made available online several hours before their occurrence, would be of significant benefit to several economic sectors and for planning human activities. Site-specific and reasonably accurate nowcasts of daily minimum temperature several hours before its occurrence, using measured sub-hourly temperatures hours earlier in the morning as model inputs, was investigated. Various temperature models were tested for their ability to accurately nowcast daily minimum temperatures 2 or 4 h before sunrise. Temperature datasets used for the model nowcasts included sub-hourly grass and grass-surface (infrared) temperatures from one location in South Africa and air temperature from four subtropical sites varying in altitude (USA and South Africa) and from one site in central sub-Saharan Africa. Nowcast models used employed either exponential or square root functions to describe the rate of nighttime temperature decrease but inverted so as to determine the minimum temperature. The models were also applied in near real-time using an open web-based system to display the nowcasts. Extrapolation algorithms for the site-specific nowcasts were also implemented in a datalogger in an innovative and mathematically consistent manner. Comparison of model 1 (exponential) nowcasts vs measured daily minima air temperatures yielded root mean square errors (RMSEs) <1 °C for the 2-h ahead nowcasts. Model 2 (also exponential), for which a constant model coefficient ( b = 2.2) was used, was usually slightly less accurate but still with RMSEs <1 °C. Use of model 3 (square root) yielded increased RMSEs for the 2-h ahead comparisons between nowcasted and measured daily minima air temperature, increasing to 1.4 °C for some sites. For all sites for all models, the comparisons for the 4-h ahead air temperature nowcasts generally yielded increased RMSEs, <2.1 °C. Comparisons for all model nowcasts of the daily grass

  14. De novo assembly and characterization of the transcriptome of broomcorn millet (Panicum miliaceum L. for gene discovery and marker development

    Directory of Open Access Journals (Sweden)

    Hong Yue

    2016-07-01

    Full Text Available Broomcorn millet (Panicum miliaceum L. is one of the world’s oldest cultivated cereals, which is well adapted to extreme environments such as drought, heat and salinity with an efficient C4 carbon fixation. Discovery and identification of genes involved in these processes will provide valuable information to improve the crop for meeting the challenge of global climate change. However, the lack of genetic resources and genomic information make gene discovery and molecular mechanism studies very difficult. Here, we sequenced and assembled the transcriptome of broomcorn millet using Illumina sequencing technology. After sequencing, a total of 45,406,730 and 51,160,820 clean paired-end reads were obtained for two genotypes Yumi No.2 and Yumi No.3. These reads were mixed and then assembled into 113,643 unigenes, with the length ranging from 351 to 15,691 bp, of which 62,543 contings could be assigned to 315 gene ontology (GO categories. Cluster of orthologous groups and kyoto encyclopedia of genes and genomes (KEGG analyses assigned could map 15,514 unigenes into 202 KEGG pathways and 51,020 unigenes to 25 COG categories, respectively. Furthermore, 35,216 simple sequence repeats (SSRs were identified in 27,055 unigene sequences, of which trinucleotides were the most abundant repeat unit, accounting for 66.72% of SSRs. In addition, 292 differentially expressed genes (DEGs were identified between the two genotypes, which were significantly enriched in 88 GO terms and 12 KEGG pathways. Finally, the expression patterns of 4 selected transcripts were validated through quantitative reverse transcription PCR (qRT-PCR analysis. Our study for the first time sequenced and assembled the transcriptome of broomcorn millet, which not only provided a rich sequence resource for gene discovery and marker development in this important crop, but will also facilitate the further investigation of the molecular mechanism of its favored agronomic traits and beyond.

  15. NEW STRAIN PRODUCERS OF BIOBUTANOL. III. METHODS OF INCREASED BUTANOL ACCUMULATION FROM BIOMASS OF SWITCHGRASS Panicum virgatum L.

    Directory of Open Access Journals (Sweden)

    Tigunova O. O.

    2015-08-01

    Full Text Available The aim of this work was to enlarge accumulation of butanol from switchgrass Panicum virgatum L. biomass using strains-producers obtained from grounds and silts of Kyiv lakes. The objects of the study were strains of C. acetobutylicum ІМВ B-7407 (IFBG C6H, Clostridium acetobutylicum IFBG C6H 5М and Clostridium tyrobutyricum IFBG C4B from the "Collections of microbial strains and lines of plants for food and agricultural biotechnology" of the Public Institution "Institute of Food Biotechnology and Genomics" of the National Academy of Sciences of Ukraine. Gas chromatography was used to determine the alcohol concentration at the stage of solvent synthesis. To determine the effect of butanol precursors during cultivation, butyric, lactic and acetic acids were used. Optimization of processing parameters, which was based on the needs of cultures, allowed us to increase the yield by 20 and 50% for the initial and mutant strain respectively. Using synthetic precursors (such as lactic, butyric and acetic acid during cultivation increased total concentration of butanol by 1.7 times. To optimize the process, a study was carried out using acetone- butyl grains. Using of acetone-butyl grains in concentrations up to 60% does not affect the synthesis of butanol by C. acetobutylicum IFBG C6H 5M. Increasing the concentration of grains led to decrease in accumulation of butanol. Almost double increase in accumulation of the target product (butanol was achieved using two-stage fermentation and/or precursors of synthesis. It was shown the possibility of using acetone-butyl grains in fermentation. As a result the mass fraction of the waste was reduced.

  16. Identification and overexpression of a Knotted1-like transcription factor in switchgrass (Panicum virgatum L. for lignocellulosic feedstock improvement

    Directory of Open Access Journals (Sweden)

    Wegi eWuddineh

    2016-04-01

    Full Text Available High biomass production and wide adaptation has made switchgrass (Panicum virgatum L. an important candidate lignocellulosic bioenergy crop. One major limitation of this and other lignocellulosic feedstocks is the recalcitrance of complex carbohydrates to hydrolysis for conversion to biofuels. Lignin is the major contributor to recalcitrance as it limits the accessibility of cell wall carbohydrates to enzymatic breakdown into fermentable sugars. Therefore, genetic manipulation of the lignin biosynthesis pathway is one strategy to reduce recalcitrance. Here, we identified a switchgrass Knotted1 transcription factor, PvKN1, with the aim of genetically engineering switchgrass for reduced biomass recalcitrance for biofuel production. Gene expression of the endogenous PvKN1 gene was observed to be highest in young inflorescences and stems. Ectopic overexpression of PvKN1 in switchgrass altered growth, especially in early developmental stages. Transgenic lines had reduced expression of most lignin biosynthetic genes accompanied by a reduction in lignin content suggesting the involvement of PvKN1 in the broad regulation of the lignin biosynthesis pathway. Moreover, the reduced expression of the Gibberellin 20-oxidase (GA20ox gene in tandem with the increased expression of Gibberellin 2-oxidase (GA2ox genes in transgenic PvKN1 lines suggest that PvKN1 may exert regulatory effects via modulation of GA signalling. Furthermore, overexpression of PvKN1 altered the expression of cellulose and hemicellulose biosynthetic genes and increased sugar release efficiency in transgenic lines. Our results demonstrated that switchgrass PvKN1 is a putative ortholog of maize KN1 that is linked to plant lignification and cell wall and development traits as a major regulatory gene. Therefore, targeted overexpression of PvKN1 in bioenergy feedstocks may provide one feasible strategy for reducing biomass recalcitrance and simultaneously improving plant growth characteristics.

  17. The enhancement of biological ocular UV radiation on beaches compared to the radiation on grass.

    Science.gov (United States)

    Liu, Guang-Cong; Wang, Fang; Gao, Yan-Yan; Yang, Zheng; Hu, Li-Wen; Gao, Qian; Ri, Jun-Chol; Liu, Yang

    2014-12-01

    The influence of albedo on ocular UV exposure has seldom been reported. This paper aimed to explore the enhancement effect on measured ocular UV radiation due to a sand surface compared to measured ocular UV radiation due to a grass surface. We measured ambient and ocular UV radiation over the beach and grass surface in Sanya City of China (18.4°N, 109.7°E). The experimental apparatus was composed of a manikin and a dual-detector spectrometer. Integration of both UVA and UVB radiation was used to denote UV radiation. Then biologically effective ocular UVB radiation (UVBE) and the ratios of UVBE of two surfaces were calculated. Maximum of ocular UV radiation versus time over the two surfaces is bimodal. UVBE on the beach is significantly larger than UVBE on the sand, and UVBE peaked at different solar elevation angle (SEA) over the two surfaces (about 53° and 40° on the beach and grass, respectively, according to Bayesian regression). The maximum of ocular UVBE ratios is greater than two, which peaked SEA was about 50°. One hour's cumulative radiation under sunny weather exceeds thresholds for photokeratitis, conjunctivitis and lens damage. Higher albedo significantly increased biological ocular UV radiation. Tourists on tropical beaches should take protective measures and avoid facing the sun directly, especially when SEA is around 50°. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. ANATOMIC STRUCTURE OF CAMPANULA ROTUNDIFOLIA L. GRASS

    OpenAIRE

    V. N. Bubenchikova; E. A. Nikitin

    2017-01-01

    The article present results of the study for a anatomic structure of Campanula rotundifolia grass from Campanulaceae family. Despite its dispersion and application in folk medicine, there are no data about its anatomic structure, therefore to estimate the indices of authenticity and quality of raw materials it is necessary to develop microdiagnostical features in the first place, which could help introducing of thisplant in a medical practice. The purpose of this work is to study anatomical s...

  19. Factors influencing seed germination in Cerrado grasses

    OpenAIRE

    Kolb, Rosana Marta; Pilon, Natashi Aparecida Lima; Durigan, Giselda

    2016-01-01

    Few studies address the ecology of herbs of Cerrado grasslands, which are ecosystems where the long dry season, high temperatures, insolation, fire and invasive grasses greatly influencing germination and the establishment of plants. We assessed germination of 13 species of Poaceae from Cerrado grasslands under nursery conditions or in germination chambers, the latter with i) recently collected seeds and seeds after six months storage, ii) under constant and alternating temperatures, and iii)...

  20. Invasive warm-season grasses reduce mycorrhizal root colonization and biomass production of native prairie grasses.

    Science.gov (United States)

    Wilson, Gail W T; Hickman, Karen R; Williamson, Melinda M

    2012-07-01

    Soil organisms play important roles in regulating ecosystem-level processes and the association of arbuscular mycorrhizal (AM) fungi with a plant species can be a central force shaping plant species' ecology. Understanding how mycorrhizal associations are affected by plant invasions may be a critical aspect of the conservation and restoration of native ecosystems. We examined the competitive ability of old world bluestem, a non-native grass (Caucasian bluestem [Bothriochloa bladhii]), and the influence of B. bladhii competition on AM root colonization of native warm-season prairie grasses (Andropogon gerardii or Schizachyrium scoparium), using a substitutive design greenhouse competition experiment. Competition by the non-native resulted in significantly reduced biomass production and AM colonization of the native grasses. To assess plant-soil feedbacks of B. bladhii and Bothriochloa ischaemum, we conducted a second greenhouse study which examined soil alterations indirectly by assessing biomass production and AM colonization of native warm-season grasses planted into soil collected beneath Bothriochloa spp. This study was conducted using soil from four replicate prairie sites throughout Kansas and Oklahoma, USA. Our results indicate that a major mechanism in plant growth suppression following invasion by Bothriochloa spp. is the alteration in soil microbial communities. Plant growth was tightly correlated with AM root colonization demonstrating that mycorrhizae play an important role in the invasion of these systems by Bothriochloa spp. and indicating that the restoration of native AM fungal communities may be a fundamental consideration for the successful establishment of native grasses into invaded sites.

  1. Peanut cake concentrations in massai grass silage

    Directory of Open Access Journals (Sweden)

    Luciano S. Lima

    2013-03-01

    Full Text Available Objective. This experiment was conducted to evaluate the best concentration of peanut cake in the ensiling of massai grass of the chemical-bromatological composition, fermentative characteristics, forage value rate, ingestion estimates, and digestibility of dry matter in the silage. Materials and methods. The experiment was carried out at the Experimental Farm of São Gonçalo dos Campos at the Federal University of Bahia, Brazil. The treatments consisted of massai grass that was cut at 40 days and dehydrated, in addition to 0%, 8%, 16%, and 24% peanut cake in the fresh matter and treatment without cake. The material was compressed in experimental silos (7 liter that were opened after 76 days. Results. The addition of 8-24% peanut cake improved the silage’s chemical-bromatological parameters, increased the dry matter and non-fiber carbohydrates and reduced the fibrous components. There was a linear increase in the estimated values of digestibility and the ingestion of dry matter depending on the levels of peanut cake in the silage. There was an improvement in the fermentative characteristics, with a quadratic effect positive for levels of ammoniacal nitrogen. The forage value rate increased linearly with the inclusion of peanut cake. Conclusions. The inclusion of up to 24% peanut cake during ensiling of massai grass increases the nutritive value of silage and improves fermentation characteristics.

  2. Ethnobotanical studies of fodder grass resources for ruminant animals, based on the traditional knowledge of indigenous communities in Central Punjab Pakistan.

    Science.gov (United States)

    Harun, Nidaa; Chaudhry, Abdul Shakoor; Shaheen, Shabnum; Ullah, Kifayat; Khan, Farah

    2017-10-04

    Traditional knowledge of indigenous plants is pivotal in developing strategies to feed livestock sustainably in low input systems. Likewise, in Pakistan the indigenous people of Central Punjab have been using their regional grasses as a ruminant fodder for centuries. This study evaluated the indigenous traditional knowledge to ascertain the value of various fodder grasses to optimise their use to feed livestock in Central Punjab. The snowball technique was employed to identify key informants who had relevant knowledge about different grasses in the study area. Semi-structured questionnaires, face-to-face interviews and site visits were used for describing the fodder grasses. The data were then analysed by using relative frequency citation and pairwise comparison methods to determine the order of priority among the listed fodder grasses. Furthermore, SPSS 22 software was used for descriptive statistics and interpretation of associations among studied parameters. Microsoft Excel was used to present data as % values and graphs. Overall, 53 grasses were described with ethnobotanical information regarding their uses for fodder, ethnoveterinary and other purposes. All these grasses belonged to the family Poaceae where the subfamily Panicoideae had the maximum number of 30 grasses. We categorized these grasses into high (A), medium (B) and low priority (C) groups where the group A grasses were reported as not only the most abundant but also the most palatable forages to all ruminants. Their higher demand was reflected by the feeding systems of both ad libitum grazing and feeding after cutting and mixing with other feeds. The study also revealed 37 previously unreported ethnoveterinary uses of these grasses. The results have reinforced the value of conserving ethnobotanical knowledge, being poorly documented previously, in developing strategies to feed livestock. It indicated the preferred fodder grasses as well as the possible reasons of their preference. The reported

  3. Vibrational mode analysis using maximum likelihood and maximum entropy

    International Nuclear Information System (INIS)

    Redondo, A.; Sinha, D.N.

    1993-01-01

    A simple algorithm is presented that uses the maximum likelihood and maximum entropy approaches to determine the vibrational modes of elastic bodies. This method assumes that the vibrational frequencies have been previously determined, but the modes to which they correspond are unknown. Although the method is illustrated through the analysis of simulated vibrational modes for a flat rectangular plate, it has broad applicability to any experimental technique in which spectral frequencies can be associated to specific modes by means of a mathematical model

  4. Treatment of grass pollen allergy: focus on a standardized grass allergen extract - Grazax®.

    Science.gov (United States)

    Calderón, Moisés; Brandt, Tove

    2008-12-01

    Immunotherapy is the only treatment for allergy that has the potential to alter the natural course of the disease. Sublingual immunotherapy (SLIT) for grass pollen-induced rhino-conjunctivitis has been developed to make immunotherapy available to a broader group of allergic patients. In the largest clinical programme ever conducted with allergen-specific immunotherapy, over 1,700 adults and 260 children have been exposed to Grazax(®). Grazax is formulated as an oral lyophilisate (tablet) for sublingual administration, containing 75,000 SQ-T standardized allergen extract of grass pollen from Phleum pratense. Grazax is indicated for treatment of grass pollen-induced rhinitis and conjunctivitis in adult patients with clinically relevant symptoms and diagnosed with a positive skin prick test and/or specific IgE test to grass pollen. In phase I trials doses from 2,500 to 1,000,000 SQ-T were tested. All doses were well tolerated and 75,000 SQ-T, with approximately 15 mug major allergen protein, was chosen as the optimal dose. Three phase III trials are ongoing, one being a long-term trial. Results from GT-08 trial first and second treatment years showed a reduction of 30% and 36%, respectively, in daily rhino-conjunctivitis symptom scores and a reduction of 38% and 46% of daily rhino-conjunctivitis medication scores compared with placebo over the entire grass pollen season. Subjects treated with Grazax also had an increased number of well days and improved quality of life, and more subjects experienced excellent rhino-conjunctivitis control. The most common adverse events related to Grazax are local reactions, such as pruritus, edema mouth, ear pruritus, throat irritation, and sneezing. We conclude that Grazax is efficacious and safe for treatment of rhino-conjunctivitis due to grass pollen allergy.

  5. The importance of cross-reactivity in grass pollen allergy

    Directory of Open Access Journals (Sweden)

    Aleksić Ivana

    2014-01-01

    Full Text Available According to the data obtained from in vivo and in vitro testing in Serbia, a significant number of patients have allergic symptoms caused by grass pollen. We examined the protein composition of grass pollens (Dactylis glomerata, Lolium perenne and Phleum pratense and cross-reactivity in patients allergic to grass pollen from our region. The grass pollen allergen extract was characterized by SDS-PAGE, while cross-reactivity of single grass pollens was revealed by immunoblot analysis. A high degree of cross-reactivity was demonstrated for all three single pollens in the sera of allergic patients compared to the grass pollen extract mixture. Confirmation of the existence of cross-reactivity between different antigenic sources facilitates the use of monovalent vaccines, which are easier to standardize and at the same time prevent further sensitization of patients and reduces adverse reactions. [Projekat Ministarstva nauke Republike Srbije, br. 172049 i br. 172024

  6. Rye-grass as an energy crop using biogas technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-11-15

    The viability of using rye-grass in the UK as a wet energy crop was investigated in this project. The harvesting of rye-grass, the operation of pilot-scale digesters fed with cut rye-grass, and the operation of a biogas plant are described. Use of the digestate as a fertilizer for the grass was examined and the need for added farm manure or slurry to enrich the nutrient content of the grass and produce better yields is noted. Details are given of the digester design and the design of a commercial-scale biogas plant able to take a variety of liquid and solid feeds. Energy balance, the economics of the commercial design, the ensiling of the grass, and methane yields are considered.

  7. OECD Maximum Residue Limit Calculator

    Science.gov (United States)

    With the goal of harmonizing the calculation of maximum residue limits (MRLs) across the Organisation for Economic Cooperation and Development, the OECD has developed an MRL Calculator. View the calculator.

  8. Goat milk production and quality on Tanzania-grass pastures, with supplementation - doi: 10.4025/actascianimsci.v34i4.14339

    Directory of Open Access Journals (Sweden)

    Ana Clara Rodrigues Cavalcante

    2012-10-01

    Full Text Available It was evaluated the production and quality of milk produced by goats grazing Panicum maximum Jacq cv. Tanzania (Guineagrass and receiving four levels of concentrate supplementation. Eight Anglo Nubian goats, aged between two and four years, 43.6 kg in average body weight and between the 2nd and 4th lactation were distributed into two 4 x 4 balanced Latin square design. The supplementation levels were: 0.0, 0.5, 1.0 and 1.5% of body weight. The concentrate was composed of corn and soybean meal. The intake of dry matter and nutrients, and the daily production of milk, 4% fat-corrected milk, fat, protein, lactose and total solids had increased (p

  9. Determining the regional potential for a grass biomethane industry

    International Nuclear Information System (INIS)

    Smyth, Beatrice M.; Smyth, Henry; Murphy, Jerry D.

    2011-01-01

    Research highlights: → We identified assessment criteria for determining the regional potential for grass biomethane. → Grass biomethane is distributed via the natural gas grid. → The criteria include: land use; grass yields; gas grid coverage; availability of co-substrates. → The county with the highest potential can fuel 50% of cars or supply 130% of domestic gas consumption. - Abstract: Grass biogas/biomethane has been put forward as a renewable energy solution and it has been shown to perform well in terms of energy balance, greenhouse gas emissions and policy constraints. Biofuel and energy crop solutions are country-specific and grass biomethane has strong potential in countries with temperate climates and a high proportion of grassland, such as Ireland. For a grass biomethane industry to develop in a country, suitable regions (i.e. those with the highest potential) must be identified. In this paper, factors specifically related to the assessment of the potential of a grass biogas/biomethane industry are identified and analysed. The potential for grass biogas and grass biomethane is determined on a county-by-county basis using multi-criteria decision analysis. Values are assigned to each county and ratings and weightings applied to determine the overall county potential. The potential for grass biomethane with co-digestion of slaughter waste (belly grass) is also determined. The county with the highest potential (Limerick) is analysed in detail and is shown to have ready potential for production of gaseous biofuel to meet either 50% of the vehicle fleet or 130% of the domestic natural gas demand, through 25 facilities at a scale of ca. 30 kt yr -1 of feedstock. The assessment factors developed in this paper can be used in other resource studies into grass biomethane or other energy crops.

  10. ANATOMIC STRUCTURE OF CAMPANULA ROTUNDIFOLIA L. GRASS

    Directory of Open Access Journals (Sweden)

    V. N. Bubenchikova

    2017-01-01

    Full Text Available The article present results of the study for a anatomic structure of Campanula rotundifolia grass from Campanulaceae family. Despite its dispersion and application in folk medicine, there are no data about its anatomic structure, therefore to estimate the indices of authenticity and quality of raw materials it is necessary to develop microdiagnostical features in the first place, which could help introducing of thisplant in a medical practice. The purpose of this work is to study anatomical structureof Campanula rotundifolia grass to determine its diagnostic features. Methods. Thestudy for anatomic structure was carried out in accordance with the requirements of State Pharmacopoeia, edition XIII. Micromed laboratory microscope with digital adjutage was used to create microphotoes, Photoshop CC was used for their processing. Result. We have established that stalk epidermis is prosenchymal, slightly winding with straight of splayed end cells. After study for the epidermis cells we established that upper epidermis cells had straight walls and are slightly winding. The cells of lower epidermishave more winding walls with prolong wrinkled cuticule. Presence of simple one-cell, thin wall, rough papillose hair on leaf and stalk epidermis. Cells of epidermis in fauces of corolla are prosenchymal, with winding walls, straight or winding walls in a cup. Papillary excrescences can be found along the cup edges. Stomatal apparatus is anomocytic. Conclusion. As the result of the study we have carried out the research for Campanula rotundifolia grass anatomic structure, and determined microdiagnostic features for determination of raw materials authenticity, which included presence of simple, one-cell, thin-walled, rough papillose hair on both epidermises of a leaf, along the veins, leaf edge, and stalk epidermis, as well as the presence of epidermis cells with papillary excrescences along the edges of leaves and cups. Intercellular canals are situatedalong the

  11. Molecular analysis of stomach contents reveals important grass seeds in the winter diet of Baird's and Grasshopper sparrows, two declining grassland bird species.

    Science.gov (United States)

    Titulaer, Mieke; Melgoza-Castillo, Alicia; Panjabi, Arvind O; Sanchez-Flores, Alejandro; Martínez-Guerrero, José Hugo; Macías-Duarte, Alberto; Fernandez, Jesús A

    2017-01-01

    We analyzed the diet of Baird's Sparrow (Ammodramus bairdii) and Grasshopper Sparrow (A. savannarum) in three different sites and sampling periods across the Chihuahuan Desert in northern Mexico. DNA from seeds in regurgitated stomach contents was sequenced using NGS technology and identified with a barcoding approach using the P6 loop of the trnL intron as genetic marker. During each sampling period, we collected random soil samples to estimate seed availability in the soil seed bank. Due to the variability and size of the genetic marker, the resolution was limited to a family level resolution for taxonomic classification of seeds, but in several cases a genus level was achieved. Diets contained a high diversity of seeds but were dominated by a limited number of genera/families. Seeds from Panicoideae (from the genera Panicum, Setaria, Eriochloa, Botriochloa, and Hackelochloa) contributed for the largest part to the diets (53 ± 19%), followed by Bouteloua (10 ± 12%). Depending on the site and sampling period, other important seeds in the diets were Eragrostideae, Pleuraphis, Asteraceae, Verbena, and Amaranthus. The most abundant seeds were not always preferred. Aristida and Chloris were common in the soil seed bank but these seeds were avoided by both bird species. Baird's and Grasshopper sparrows did not differ in seed preferences. This work highlights the importance of range management practices that favor seed production of Panicoideae and Bouteloua grasses to enhance winter habitat use and survival of Baird's and Grasshopper sparrows in the Chihuahuan Desert.

  12. Upgrated fuel from reed canary grass

    Energy Technology Data Exchange (ETDEWEB)

    Oravainen, H. [VTT Energy, Jyvaeskylae (Finland)

    1997-12-01

    Results described in this presentation are from a large EU-project - Development of a new crop production system based on delayed harvesting and system for its combined processing to chemical pulp and biofuel powder. This is a project to develop the use of Reed Canary Grass (Phalaris Arundinaceae) both for pulp industry and energy production. The main contractor of the project is Swedish University of Agricultural Sciences (coordinator), task coordinators are United Milling Systems A/S from Denmark, and Jaakko Poeyry Oy and VTT Energy from Finland In addition, there are partners from several countries participating in the project

  13. Grass-on-grass competition along a catenal gradient in mesic ...

    African Journals Online (AJOL)

    Three aboveground treatments (full light competition, no light competition and clipping to simulate grazing), and two belowground treatments (full belowground competition and belowground competition excluded by a root tube), were used. On all soil depths the three grass species differed in mean mass, with E. racemosa ...

  14. Nutritional value of cabbage and kikuyu grass as food for grass carp ...

    African Journals Online (AJOL)

    weighing). Fish were fed once a-day. The feed refusal was measured daily by siphoning out the debris on the bottom of the aquaria which was collected on a sieve .... raising grass carp without the need for supplementary feeding. Cabbage is widely produced on both a subsis- tence and commercial scale by local farmers.

  15. Treatment of grass pollen allergy: focus on a standardized grass allergen extract – Grazax®

    Directory of Open Access Journals (Sweden)

    Moisés Calderón

    2008-11-01

    Full Text Available Moisés Calderón1, Tove Brandt21Section of Allergy and Clinical Immunology, Royal Brompton Hospital, Imperial College, NHLI, London, UK; 2Group Clinical Development, ALK-Abelló A/S, Hørsholm, DenmarkAbstract: Immunotherapy is the only treatment for allergy that has the potential to alter the natural course of the disease. Sublingual immunotherapy (SLIT for grass pollen-induced rhino-conjunctivitis has been developed to make immunotherapy available to a broader group of allergic patients. In the largest clinical programme ever conducted with allergen-specific immunotherapy, over 1,700 adults and 260 children have been exposed to Grazax®. Grazax is formulated as an oral lyophilisate (tablet for sublingual administration, containing 75,000 SQ-T standardized allergen extract of grass pollen from Phleum pratense. Grazax is indicated for treatment of grass pollen-induced rhinitis and conjunctivitis in adult patients with clinically relevant symptoms and diagnosed with a positive skin prick test and/or specific IgE test to grass pollen. In phase I trials doses from 2,500 to 1,000,000 SQ-T were tested. All doses were well tolerated and 75,000 SQ-T, with approximately 15 µg major allergen protein, was chosen as the optimal dose. Three phase III trials are ongoing, one being a long-term trial. Results from GT-08 trial first and second treatment years showed a reduction of 30% and 36%, respectively, in daily rhino-conjunctivitis symptom scores and a reduction of 38% and 46% of daily rhinoconjunctivitis medication scores compared with placebo over the entire grass pollen season. Subjects treated with Grazax also had an increased number of well days and improved quality of life, and more subjects experienced excellent rhino-conjunctivitis control. The most common adverse events related to Grazax are local reactions, such as pruritus, edema mouth, ear pruritus, throat irritation, and sneezing. We conclude that Grazax is efficacious and safe for treatment

  16. Aluminum-induced oxidative stress and neurotoxicity in grass carp (Cyprinidae--Ctenopharingodon idella).

    Science.gov (United States)

    Fernández-Dávila, María Lourdes; Razo-Estrada, Amparo Celene; García-Medina, Sandra; Gómez-Oliván, Leobardo Manuel; Piñón-López, Manuel Jesús; Ibarra, Rocio Guzmán; Galar-Martínez, Marcela

    2012-02-01

    Aluminum is used in a large number of anthropogenic processes, leading to aquatic ecosystems pollution. Diverse studies show that in mammals this metal may produce oxidative stress, is neurotoxic, and is involved in the development of neurodegenerative disorders, such as Alzhaimer's and Parkinson's diseases. Nevertheless, there are only few studies with respect to Al-induced neurotoxicity on aquatic fauna, particularly on fishes of economical interest, such as the grass carp (Ctenopharingodon idella). This study evaluates Al-induced toxicity on the grass carp C. idella. Specimens were exposed to the maximum concentration allowed in order to protect aquatic life (0.1 mg L⁻¹), for 12, 24, 48, 72 and 96 h. After the exposure time, lipid peroxidation degree, superoxide dismutase and catalase activity, as well as dopamine, adrenaline and noradrenaline levels were evaluated. Al concentration in organisms and water was also measured, in order to determine the bioconcentration factor. Results show that Al bioconcentrates in grass carp inducing oxidative stress (increment of 300 and 455 percent on lipid peroxidation degree and SOD activity, and decrement of 49 percent on CAT activity) and neurotoxicity (increment of 55 and 155 percent on dopamine and adrenaline levels and decrement of 93 percent on noradrenaline level). Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Factors influencing seed germination in Cerrado grasses

    Directory of Open Access Journals (Sweden)

    Rosana Marta Kolb

    2016-03-01

    Full Text Available Few studies address the ecology of herbs of Cerrado grasslands, which are ecosystems where the long dry season, high temperatures, insolation, fire and invasive grasses greatly influencing germination and the establishment of plants. We assessed germination of 13 species of Poaceae from Cerrado grasslands under nursery conditions or in germination chambers, the latter with i recently collected seeds and seeds after six months storage, ii under constant and alternating temperatures, and iii in the presence and absence of light. Germinability, mean germination time (MGT and required light were quantified to elucidate factors involved in successful germination. Germinability was low for most grasses, probably because of low seed viability. For most species, germinability and MGT were not altered by seed storage. Germination percentages were higher at alternating temperatures and in the presence of light, factors that are more similar to natural environmental situations compared with constant temperature or the absence of light. Our findings indicate that alternating temperatures and light incidence are key factors for germination of species of Poaceae. The maintenance of these environmental factors, which are crucial for the conservation of Cerrado grasslands, depends on appropriate management interventions, such as fire management and the control of biological invasion.

  18. Genetic modification of wetland grasses for phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Czako, M.; Liang Dali; Marton, L. [Dept. of Biological Sciences, Univ. of South Carolina, Columbia, SC (United States); Feng Xianzhong; He Yuke [National Lab. of Plant Molecular Genetics, Shanghai Inst. of Plant Physiology, Chinese Academy of Sciences, Shanghai, SH (China)

    2005-04-01

    Wetland grasses and grass-like monocots are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Tissue culture is prerequisite for genetic manipulation, and methods are reported here for in vitro culture and micropropagation of a number of wetland plants of various ecological requirements such as salt marsh, brackish water, riverbanks, and various zones of lakes and ponds, and bogs. The monocots represent numerous genera in various families such as Poaceae, Cyperaceae, Juncaceae, and Typhaceae. The reported species are in various stages of micropropagation and Arundo donax is scaled for mass propagation for selecting elite lines for pytoremediation. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is also reported here. All but one transgenic lines contained both the organomercurial lyase (merB) and mercuric reductase (merA) sequences showing that co-introduction into Spartina of two genes from separate Agrobacterium strains is possible. (orig.)

  19. Elephant grass clones for silage production

    Directory of Open Access Journals (Sweden)

    Rerisson José Cipriano dos Santos

    2013-02-01

    Full Text Available Ensiling warm-season grasses often requires wilting due to their high moisture content, and the presence of low-soluble sugars in these grasses usually demands the use of additives during the ensiling process. This study evaluated the bromatological composition of the fodder and silage from five Pennisetum sp. clones (IPA HV 241, IPA/UFRPE Taiwan A-146 2.114, IPA/UFRPE Taiwan A-146 2.37, Elephant B, and Mott. The contents of 20 Polyvinyl chloride (PVC silos, which were opened after 90 days of storage, were used for the bromatological analysis and the evaluation of the pH, nitrogen, ammonia, buffer capacity, soluble carbohydrates, and fermentation coefficients. The effluent losses, gases and dry matter recovery were also calculated. Although differences were observed among the clones (p < 0.05 for the concentrations of dry matter, insoluble nitrogen in acid detergents, insoluble nitrogen in neutral detergents, soluble carbohydrates, fermentation coefficients, and in vitro digestibility in the forage before ensiling, no differences were observed for most of these variables after ensiling. All of the clones were efficient in the fermentation process. The IPA/UFRPE TAIWAN A-146 2.37 clone, however, presented a higher dry matter concentration and the best fermentation coefficient, resulting in a better silage quality, compared to the other clones.

  20. From pasture grass to cattle milk

    International Nuclear Information System (INIS)

    Miyamoto, Susumu

    1979-01-01

    Iodine-131 is one of the important fission products since it is selectively accumulated in the thyroid gland of man. The transfer of this isotope from contaminated grass to cows' milk is therefore of particular importance since milk is a major constituent of the diet especially for infants. The purpose of this paper is to discuss the transfer rate of this isotope from grass to milk of lactuating cows and its distribution in milk. It is said that the orally administered iodide is rapidly absorbed through the rumen wall and excreted mainly to urine. The absorbed iodine is accumulated highly in the thyroid gland and the considerable amount is secreted to milk. Garner et al. showed that about 5% of a dose of 131 I was found in the milk within 7 days. The extremes were 1.43 to 16.4%. Present author obtained that 18 - 30% of the dosed 131 I was secreted into milk within 7 days, indicating somewhat higher transfer rate than that of Garner et al. It was reported that more than 90% of 131 I was found in milk serum in the ionic form. The countermeasures for diminishing 131 I in milk were also presented. (author)

  1. Composition and hydrothermal pretreatment and enzymatic saccharification performance of grasses and legumes from a mixed-species prairie

    Directory of Open Access Journals (Sweden)

    DeMartini Jaclyn D

    2011-11-01

    Full Text Available Abstract Background Mixtures of prairie species (mixed prairie species; MPS have been proposed to offer important advantages as a feedstock for sustainable production of fuels and chemicals. Therefore, understanding the performance in hydrothermal pretreatment and enzymatic hydrolysis of select species harvested from a mixed prairie is valuable in selecting these components for such applications. This study examined composition and sugar release from the most abundant components of a plot of MPS: a C3 grass (Poa pratensis, a C4 grass (Schizachyrium scoparium, and a legume (Lupinus perennis. Results from this study provide a platform to evaluate differences between grass and leguminous species, and the factors controlling their recalcitrance to pretreatment and enzymatic hydrolysis. Results Significant differences were found between the grass and leguminous species, and between the individual anatomical components that influence the recalcitrance of MPS. We found that both grasses contained higher levels of sugars than did the legume, and also exhibited higher sugar yields as a percentage of the maximum possible from combined pretreatment and enzymatic hydrolysis. Furthermore, particle size, acid-insoluble residue (AcIR, and xylose removal were not found to have a direct significant effect on glucan digestibility for any of the species tested, whereas anatomical composition was a key factor in both grass and legume recalcitrance, with the stems consistently exhibiting higher recalcitrance than the other anatomical fractions. Conclusions The prairie species tested in this study responded well to hydrothermal pretreatment and enzymatic saccharification. Information from this study supports recommendations as to which plant types and species are more desirable for biological conversion in a mixture of prairie species, in addition to identifying fractions of the plants that would most benefit from genetic modification or targeted growth.

  2. ( Abelmoschus esculentus (L.) Moench) to weed control by mulching

    African Journals Online (AJOL)

    The effects of mulching material on okra performance during the rainy seasons of 1999 and 2000 were evaluated at the Teaching and Research Farm of the Ladoke Akintola University of Technology, Ogbomoso, Nigeria. Three mulch types–plastic mulch, grass mulch (Panicum maximum) and wood shavings (of Tectonia ...

  3. Limestone quarrying : the impact on the vegetation and landform of ...

    African Journals Online (AJOL)

    Species composition of the vegetation of several sites (worked; unworked; spoil heap in the quarry and its environs) in a cement manufacturing town, Sagamu, ... The dominant grass species across all the sites were Andropogon tectorum, Panicum maximum, Penisetum purpureum and Sorghum bicor, and forb species were ...

  4. Browse Title Index

    African Journals Online (AJOL)

    Items 551 - 600 of 1346 ... Vol 3, No 3 (1986), Influence of soil pH and fertilization on the dry matter production, chemical composition and digestibility of perennial grasses: II: Panicum maximum Jacq. Abstract. LG Du Pisani, DPJ Opperman, WLJ van Rensburg. Vol 4, No 4 (1987), Influence of sowing depth on the germination ...

  5. Effect of maturity stage and processing on chemical composition, in ...

    African Journals Online (AJOL)

    Effect of maturity stage and processing on chemical composition, in vitro gas production and preference of Panicum maximum and Pennisetum purpureum. ... It is concluded that in order to optimize DM intake farmers should consider the type of grasses and their age at harvest particularly for Muturu. Pelleting improves ...

  6. Studies of heavy metal contents and microbial composition of ...

    African Journals Online (AJOL)

    This study investigated the heavy metal content and microbial composition of rhizosphere of Panicum maximum obtained from some auto mechanic workshops in Benin City, Nigeria. The grass was uprooted and soil sample was taken from its rhizosphere. The sample were labeled appropriately and immediately transported ...

  7. Effects of cutting frequency and fertilizer-N application on growth ...

    African Journals Online (AJOL)

    N rates on growth and production of guinea grass (Panicum maximum Jacq). The experiment was conducted in Nsukka, Nigeria. Treatments comprised four levels of fertilizer N (0, 150, 300 and 450 kg N ha- 1) and four cutting intervals (3, 6, ...

  8. Intake and digestibility of nutrients by wad goats fed diets containing ...

    African Journals Online (AJOL)

    CNSL) was included at four levels (0, 5, 10 and 15ml/kg DM). The concentrates in combination with Panicum maximum (40% concentrate and 60% grass) was fed to WAD goats at 5% of their metabolic weight. 12 WAD goats weighing 8.5 ...

  9. Influence of cutting frequency and fertilizer-N application on tiller ...

    African Journals Online (AJOL)

    An experiment was carried out to evaluate the effects of cutting frequency and nitrogen rates on guinea grass (Panicum maximum) tiller production and herbage yield distribution over time. Plants were grown in the Department of Crop Science Research and Teaching Farm, University of Nigeria, Nsukka. A 4 × 4 factorial ...

  10. Author Details

    African Journals Online (AJOL)

    Degradation of Crude Protein in Groundnut Cake, Guinea Grass (Panicum Maximum) and Rumen Epithelial Scraping based Diets by West African Dwarf Sheep Abstract · Vol ... Effect of dietary copper supplementation on serum copper level and performance of female West African dwarf (Fouta Djallon) goats. Abstract · Vol ...

  11. A comparative study on zero tillage with bulldozing as land ...

    African Journals Online (AJOL)

    A comparative study on zero tillage and bulldozing, as land preparations for oil palm seedling transplanted into the field was conducted at Ayip Eku Oil Palm Estate between 1993 and 1997. The experimental site was a five-year fallow land in which Panicum maximum (Guinea grass) and Centresoma pubescence were ...

  12. maXImum medical aid

    African Journals Online (AJOL)

    1990-08-04

    Aug 4, 1990 ... Over the past 5 years, the medicines price index has risen by. 152,0% (20,3% per annum). The consumer price index (CPI) increased by 108,4% .... EXAMPLES OF FOUR TYPICAL ENTRIES IN THE MMAP LIST. Maximum. "- dispensed. No. in. Approved price before. Product list name. Strength. Form. Pack.

  13. ENUGU USING MAXIMUM TEMPERATURE DATA

    African Journals Online (AJOL)

    2008-01-28

    Jan 28, 2008 ... daily global solar radiation on a horizontal surface for some towns in Nigeria. For example, Sanusi and Aliyu (2005) used maximum temperature data to predict for. Sokoto. lheonu (2001) did the same for lbadan. Badmus and Momoh(2005) did likewise for Birnin Kebbi. So did Awachie and Okeke(1 990) for ...

  14. Abolishing the maximum tension principle

    Directory of Open Access Journals (Sweden)

    Mariusz P. Da̧browski

    2015-09-01

    Full Text Available We find the series of example theories for which the relativistic limit of maximum tension Fmax=c4/4G represented by the entropic force can be abolished. Among them the varying constants theories, some generalized entropy models applied both for cosmological and black hole horizons as well as some generalized uncertainty principle models.

  15. Maximum stellar iron core mass

    Indian Academy of Sciences (India)

    Maximum stellar iron core mass mass of iron into a neutron star. The radius of this highly compressed theoretical sphere may be somewhat smaller than the actual radius of a real spherical mass of iron, just prior to core collapse, because an unstable real spherical mass of iron is likely to achieve the critical density only at its ...

  16. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore. 11 refs., 4 figs

  17. Decomposition using Maximum Autocorrelation Factors

    DEFF Research Database (Denmark)

    Larsen, Rasmus

    2002-01-01

    , normally we have an ordering of landmarks (variables) along the contour of the objects. For the case with observation ordering the maximum autocorrelation factor (MAF) transform was proposed for multivariate imagery in\\verb+~+\\$\\backslash\\$cite{switzer85}. This corresponds to a R-mode analyse of the data...

  18. Generic maximum likely scale selection

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2007-01-01

    The fundamental problem of local scale selection is addressed by means of a novel principle, which is based on maximum likelihood estimation. The principle is generally applicable to a broad variety of image models and descriptors, and provides a generic scale estimation methodology. The focus...

  19. The Maximum Density of Water.

    Science.gov (United States)

    Greenslade, Thomas B., Jr.

    1985-01-01

    Discusses a series of experiments performed by Thomas Hope in 1805 which show the temperature at which water has its maximum density. Early data cast into a modern form as well as guidelines and recent data collected from the author provide background for duplicating Hope's experiments in the classroom. (JN)

  20. Grass defoliation affecting survival and growth of seedlings of ...

    African Journals Online (AJOL)

    Two experiments were conducted, one in the field and the other in the greenhouse, to investigate the effects of the intensity and frequency of grass defoliation on the survival and growth of Acacia karroo seedlings. In the greenhouse, seedlings growing with heavily clipped grasses had higher biomass production than those ...

  1. Defoliation effects of perennial grasses – continuing confusion | DL ...

    African Journals Online (AJOL)

    Although an adequate knowledge of growth patterns and defoliation effects in perennial grasses is a prerequisite for the rational use of veld and pastures for animal production, our knowledge of this subject is far from adequate. The results of various physiological and clipping studies on tropical and sub-tropical grasses are ...

  2. Invasive grasses change landscape structure and fire behavior in Hawaii

    Science.gov (United States)

    Lisa M. Ellsworth; Creighton M. Litton; Alexander P. Dale; Tomoaki Miura

    2014-01-01

    How does potential fire behavior differ in grass-invaded non-native forests vs open grasslands? How has land cover changed from 1950–2011 along two grassland/forest ecotones in Hawaii with repeated fires? A study on non-native forest with invasive grass understory and invasive grassland (Megathyrsus maximus) ecosystems on Oahu, Hawaii, USA was...

  3. Variation in important pasture grasses. II. Cytogenetic and ...

    African Journals Online (AJOL)

    Variation in important pasture grasses. II. Cytogenetic and reproductive variation. Spies J.J., Gibbs Russell G.E.. Abstract. The chromosome numbers and reproductive variation of seven important pasture grasses from South Africa are compared. This comparison indicates that all these species form polyploid complexes, ...

  4. Home destruction examination: Grass Valley Fire, Lake Arrowhead, California

    Science.gov (United States)

    Jack D. Cohen; Richard D. Stratton

    2008-01-01

    The Grass Valley Fire started October 22, 2007 at approximately 0508, one-mile west of Lake Arrowhead in the San Bernardino Mountains. Fuel and weather conditions were extreme due to drought, dry Santa Ana winds, and chaparral and conifer vegetation on steep terrain. The fire proceeded south through the Grass Valley drainage one-mile before impacting an area of dense...

  5. Grass seeding as a control for roadbank erosion.

    Science.gov (United States)

    A.G. Wollum

    1962-01-01

    Grass, seeded on a steep roadcut in western Oregon, reduced erosion but caused increased surface runoff during a 3-year period of observation. These results were obtained at H. J. Andrews Experimental Forest from a study designed to measure effectiveness of grass in controlling soil erosion from exposed roadbanks. Additional measurements for varying soil types will be...

  6. Potentials of agricultural waste and grasses in pulp and papermaking

    African Journals Online (AJOL)

    Potentials of some agricultural waste and grasses were investigated. Potassium hydroxide from wood ash was used as alkali for pulping. Results from visopan Microscope showed that banana stalk has the highest fibre length of 2.60 mm and Bahaman grass has the least fibre length of 0.85 mm. Runkel Ratio (RK) for ...

  7. Structural traits of elephant grass ( Pennisetum purpureum Schum ...

    African Journals Online (AJOL)

    Despite the forage potential of elephant grass, controlling canopy structure during grazing has limited its use in pasture. This study was conducted to determine the effect of grazing frequency and post-grazing height on canopy structural characteristics of elephant grass genotypes. The treatments consisted of the factorial ...

  8. Effect of Bamboo ( Bambusa valgaris ) and Elephant grass ...

    African Journals Online (AJOL)

    Antioxidant potential of bamboo and elephant grass leaf extracts were evaluated in cooked and raw broiler meat stored under refrigeration at 3±20C. To a separate 350g of minced broiler meat, 1.5% bamboo leaf extract (BLE) or elephant grass extract (EGE) was added. There was a negative control without additive while a ...

  9. Agricultural field reclamation utilizing native grass crop production

    Science.gov (United States)

    J. Cure

    2013-01-01

    Developing a method of agricultural field reclamation to native grasses in the Lower San Pedro Watershed could prove to be a valuable tool for educational and practical purposes. Agricultural field reclamation utilizing native grass crop production will address water table depletion, soil degradation and the economic viability of the communities within the watershed....

  10. Effect of grass species on NDF ruminal degradability and ...

    African Journals Online (AJOL)

    uzivatel

    Abstract. The objective of this study was to compare the ruminal degradability of neutral detergent fibre (NDF) .... Felina were evaluated in the present study. The grass was harvested from the primary growth of monocultured grasses on 19 and 26 May of 2004 and 27 May and 10 ...... Nutritional Ecology of the Ruminant.

  11. Does fire maintain symbiotic, fungal endophyte infections in native grasses?

    Science.gov (United States)

    S. H. Faeth; S. M.  Haase; S. S. Sackett; T. J. Sullivan; R. H.  Remington; C. E.  Hamilton

    2002-01-01

    Systemic endophytic fungi in agronomic and turf grasses are well known for conferring increased resistance to herbivores and to abiotic stresses, such as drought, and increasing competitive abilities. Many native grasses also harbor high frequencies of the asexual and vertically-transmitted endophyte, Neotyphodium. In Festuca arizonica...

  12. MACRO NUTRIENTS UPTAKE OF FORAGE GRASSES AT DIFFERENT SALINITY STRESSES

    Directory of Open Access Journals (Sweden)

    F. Kusmiyati

    2014-10-01

    Full Text Available The high concentration of sodium chloride (NaCl in saline soils has negative effects on the growth ofmost plants. The experiment was designed to evaluate macro nutrient uptake (Nitrogen, Phosphorus andPotassium of forage grasses at different NaCl concentrations in growth media. The experiment wasconducted in a greenhouse at Forage Crops Laboratory of Animal Agriculture Faculty, Diponegoro University.Split plot design was used to arrange the experiment. The main plot was forage grasses (Elephant grass(Pennisetum purpureum and King grass (Pennisetum hybrida. The sub plot was NaCl concentrationin growth media (0, 150, and 300 mM. The nitrogen (N, phosphorus (P and potassium (K uptake in shootand root of plant were measured. The result indicated increasing NaCl concentration in growth mediasignificantly decreased the N, P and K uptake in root and shoot of the elephant grass and king grass. Thepercentage reduction percentage of N, P and K uptake at 150 mM and 300 mM were high in elephant grassand king grass. It can be concluded that based on nitrogen, phosphorus and potassium uptake, elephantgrass and king grass are not tolerant to strong and very strong saline soil.

  13. No positive feedback between fire and a nonnative perennial grass

    Science.gov (United States)

    Erika L. Geiger; Guy R. McPherson

    2005-01-01

    Semi-desert grasslands flank the “Sky Island” mountains in southern Arizona and Northern Mexico. Many of these grasslands are dominated by nonnative grasses, which potentially alter native biotic communities. One specific concern is the potential for a predicted feedback between nonnative grasses and fire. In a large-scale experiment in southern Arizona we investigated...

  14. Impact of the invader Ipomoea hildebrandtii on grass biomass ...

    African Journals Online (AJOL)

    The invasive coloniser Ipomoea hildebrandtii aggravates the problem of inadequate grass forage in Kajiado district, Kenya. To test its impact on grass biomass, nitrogen (N) mineralisation and seedling establishment, grazing and coloniser density were controlled using experimental exclosures and weeding treatments ...

  15. Response of higveld grass species to ammonium and nitrate nitrogen

    African Journals Online (AJOL)

    Forty-one populations in twenty-two species of highveld grasses were grown in pots of soil fertilized with solutions for comparing ammonium and nitrate nutrition. Cotton, tomato, cereal crops and pasture grasses were included for comparison. Roots and shoots were harvested separately, weighed and analysed for major ...

  16. Grass species composition, yield and quality under and outside tree ...

    African Journals Online (AJOL)

    A two-year study was conducted in lightly grazed areas of Matopos Research Station, Zimbabwe, to evaluate the impact of widely spaced trees on understorey grass composition, yield and quality. The study trees were Terminalia sericea and Acacia karroo. Ordination techniques using grass density and biomass as indices ...

  17. Lessons learned in managing alfalfa-grass mixtures

    Science.gov (United States)

    Grass-alfalfa mixtures have a number of benefits that make them attractive to producers. However, they can be problematic to establish and maintain. Research programs have made progress in understanding the benefits and challenges of alfalfa-grass mixtures. Mixtures may have greater winter survival ...

  18. Efficacy of Aqueous Extract of Lemon Grass ( Andropogon citratus L ...

    African Journals Online (AJOL)

    An experiment to determine the effects of lemon grass, Andropogon citratus L. extract on the rootknot nematodes (Meloidogyne spp.) of okra was conducted. Phytochemical analyses of the bioactive ingredients in lemon grass were carried out to determine the chemical compounds with nematicidal activities present in lemon ...

  19. Energy metabolism of dairy cows fed on grass

    NARCIS (Netherlands)

    Bruinenberg, M.H.; Honing, Y. van der; Agnew, R.E.; Yan, T.; Vuuren, A.M. van; Valk, H.

    2002-01-01

    Production performance of grass-fed dairy cows is often lower than expected from the estimated energy supply. To explain the overestimation of the energy content of grass for dairy cows, data from energy balance trials from three different laboratories (Wageningen, Lelystad and Hillsborough) were

  20. allergenicity and cross- reactivity of buffalo grass (stenotaphrum ...

    African Journals Online (AJOL)

    Grassland and savannah constitute important biomes in southern Africa, and a long surruner period, high temperatures and wind are major factors contributing to the production of large amounts of anemophilous grass pollen for most of the year. Grass pollen was reported by David Ordmanl to be the major aero-allergen.

  1. Analysis of Some Heavy Metals in Grass ( Paspalum Orbiculare ...

    African Journals Online (AJOL)

    The increased deposition of trace metals from vehicle exhausts on plants has raised concerns about the risks of the quality of food consumed by humans since the heavy metals emitted through the exhaust by vehicles can enter food chain through deposition on grass grazed by animals. Grass (Paspalum Orbiculare) and ...

  2. Identification of grazed grasses using epidermal characters | R ...

    African Journals Online (AJOL)

    The use of anatomical features of the abaxial epidermis of grasses is discussed for the identification of fragments of epidermis present in samples of rumen. The reliability of this technique, and the variation of the epidermal characters in two widely distributed species of grass, is given. A "Key" to identity certain genera of ...

  3. The influence of the application of grass herbicides on the ...

    African Journals Online (AJOL)

    Reports on a trial which was conducted over a period of three seasons in which the advantages of the removal of grass weeds from dryland lucerne and medic pastures determined. Two herbicide treatments, an unsprayed control and a grass herbicide treatment were compared for three seasons. Illustrates with graphs and ...

  4. Research note: Calibrating a disc pastures meter to estimate grass ...

    African Journals Online (AJOL)

    Sampling with more than 100 readings is not, however, recommended owing to the poor reward (precision) per unit of sampling effort. Keywords: coastal forest; disc meter; fire management; fuel load; grass; grasses; herbage mass; pastures; precision; regression model; sample size; south africa; standing crop; thornveld; ...

  5. Native Grass Community Management Plan for the Oak Ridge Reservation

    Energy Technology Data Exchange (ETDEWEB)

    Ryon, Michael G [ORNL; Parr, Patricia Dreyer [ORNL; Cohen, Kari [ORNL

    2007-06-01

    Land managers at the Department of Energy's Oak Ridge National Laboratory in East Tennessee are restoring native warm-season grasses and wildflowers to various sites across the Oak Ridge Reservation (ORR). Some of the numerous benefits to planting native grasses and forbs include improved habitat quality for wildlife, improved aesthetic values, lower long-term maintenance costs, and compliance with Executive Order 13112 (Clinton 1999). Challenges to restoring native plants on the ORR include the need to gain experience in establishing and maintaining these communities and the potentially greater up-front costs of getting native grasses established. The goals of the native grass program are generally outlined on a fiscal-year basis. An overview of some of the issues associated with the successful and cost-effective establishment and maintenance of native grass and wildflower stands on the ORR is presented in this report.

  6. Etude de production et de caracterisation de biocharbons de panic erige (Panicum virgatum L.) obtenus par pyrolyse

    Science.gov (United States)

    Pilon, Guillaume

    This research aimed at the production of biomass char under pyrolytic conditions, targeting biochar as soil amendment, while also considering its application as biocoal, either for bioenergy or subsequent upgrading. The production of biomass char was performed using two bench-scale, batch-type, fixed-bed reactors, each with an operating capacity of 1 and 25 gw.b. /batch, respectively. Switchgrass (Panicum virgatum) has been used for the tests. Production conditions studied implied temperatures of 300, 400 and 500 °C with short residence times (2.5 and 5 min). As well, the effect of using CO2 as vector gas has been compared to a common inert environment of N2. The effects of the previously mentioned parameters were correlated with some important physicochemical characteristics of biomass char. Analyses were also performed on complementary pyrolytic products (bio-oil and gas). The biomass char extraction was performed using a Soxhlet and dichloromethane was used as extracting solvent. The extracts were then characterized by GC-MS thus allowing the identification of several compounds. Specific pyrolysis conditions used at 300 °C - N2 with the 1 g/batch reactor, such as high heating rates as well as high convection conditions, presented advantegeous biomass char yields and properties, and, possible torrefaction process productivity improvement (in comparison to reported literature, such as Gilbert et al. [2009]). The char extracts as well as the bio-oils analysis (also performed using GC-MS), all generated from the 25 g/batch reactor, showed major differences among the compounds obtained from the CO2 and N2 environments, respectively. Several compounds observed in the char extracts appeared less concentrated in the CO2 environment vs N2, for the same reaction temperatures. As an example, at 400 °C, furfural was found only in char extracts from N2 environment as compared to the CO2 environment. Among all studied conditions (for both reactors), only naphthalene and

  7. Establishing native warm season grasses on Eastern Kentucky strip mines

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, T.G.; Larkin, J.L.; Arnett, M.B. [Univ. of Kentucky, Lexington, KY (United States). Dept. of Forestry

    1998-12-31

    The authors evaluated various methods of establishing native warm season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native warm season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, winter, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native warm season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native warm season grasses as a result of fertilization or seeding technique. Winter native warm season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and warm season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native warm season grass mixtures and the native warm season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native warm season grasses on Eastern Kentucky strip mines for wildlife habitat.

  8. Establishing native warm season grasses on Eastern Kentucky strip mines

    International Nuclear Information System (INIS)

    Barnes, T.G.; Larkin, J.L.; Arnett, M.B.

    1998-01-01

    The authors evaluated various methods of establishing native warm season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native warm season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, winter, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native warm season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native warm season grasses as a result of fertilization or seeding technique. Winter native warm season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and warm season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native warm season grass mixtures and the native warm season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native warm season grasses on Eastern Kentucky strip mines for wildlife habitat

  9. Established native perennial grasses out-compete an invasive annual grass regardless of soil water and nutrient availability

    Science.gov (United States)

    Christopher M. McGlone; Carolyn Hull Sieg; Thomas E. Kolb; Ty Nietupsky

    2012-01-01

    Competition and resource availability influence invasions into native perennial grasslands by nonnative annual grasses such as Bromus tectorum. In two greenhouse experiments we examined the influence of competition, water availability, and elevated nitrogen (N) and phosphorus (P) availability on growth and reproduction of the invasive annual grass B. tectorum and two...

  10. Pyricularia pennisetigena and P. zingibericola from invasive grasses infect signal grass, barley and wheat

    Directory of Open Access Journals (Sweden)

    Juliana Teodora de Assis Reges

    2016-06-01

    Full Text Available Fungal species from the Pyricularia genus are associated with blast disease in plants from the Poaceae family, causing losses in economically important crops such as rice, oat, rye, barley, wheat and triticale. This study aimed at characterizing the pathogenicity spectrum of P. pennisetigena and P. zingibericola to signal grass, barley and wheat, as well as comparing them with those from the species P. grisea and P. oryzae pathotype Triticum, which occur widely in the Brazilian agroecosystem. Twenty isolates of Pyricularia spp. were obtained from infected leaf samples of invasive plant species from wheat fields. The isolates classification into distinct Pyricularia species was done using molecular phylogeny based on actin and calmodulin genes. Pyricularia pennisetigena and P. zingibericola inoculated on plant leaves, at a concentration adjusted to 105 conidia mL-1, were pathogenic to signal grass, barley and wheat, with varying levels of aggressiveness.

  11. Maximum Gene-Support Tree

    Directory of Open Access Journals (Sweden)

    Yunfeng Shan

    2008-01-01

    Full Text Available Genomes and genes diversify during evolution; however, it is unclear to what extent genes still retain the relationship among species. Model species for molecular phylogenetic studies include yeasts and viruses whose genomes were sequenced as well as plants that have the fossil-supported true phylogenetic trees available. In this study, we generated single gene trees of seven yeast species as well as single gene trees of nine baculovirus species using all the orthologous genes among the species compared. Homologous genes among seven known plants were used for validation of the finding. Four algorithms—maximum parsimony (MP, minimum evolution (ME, maximum likelihood (ML, and neighbor-joining (NJ—were used. Trees were reconstructed before and after weighting the DNA and protein sequence lengths among genes. Rarely a gene can always generate the “true tree” by all the four algorithms. However, the most frequent gene tree, termed “maximum gene-support tree” (MGS tree, or WMGS tree for the weighted one, in yeasts, baculoviruses, or plants was consistently found to be the “true tree” among the species. The results provide insights into the overall degree of divergence of orthologous genes of the genomes analyzed and suggest the following: 1 The true tree relationship among the species studied is still maintained by the largest group of orthologous genes; 2 There are usually more orthologous genes with higher similarities between genetically closer species than between genetically more distant ones; and 3 The maximum gene-support tree reflects the phylogenetic relationship among species in comparison.

  12. Treatment of grass pollen allergy: focus on a standardized grass allergen extract – Grazax®

    OpenAIRE

    Calderón, Moisés

    2008-01-01

    Moisés Calderón1, Tove Brandt21Section of Allergy and Clinical Immunology, Royal Brompton Hospital, Imperial College, NHLI, London, UK; 2Group Clinical Development, ALK-Abelló A/S, Hørsholm, DenmarkAbstract: Immunotherapy is the only treatment for allergy that has the potential to alter the natural course of the disease. Sublingual immunotherapy (SLIT) for grass pollen-induced rhino-conjunctivitis has been developed to make immunotherapy available t...

  13. Treatment of grass pollen allergy: focus on a standardized grass allergen extract ? Grazax ?

    OpenAIRE

    Calder?n, Mois?s; Brandt, Tove

    2008-01-01

    Immunotherapy is the only treatment for allergy that has the potential to alter the natural course of the disease. Sublingual immunotherapy (SLIT) for grass pollen-induced rhino-conjunctivitis has been developed to make immunotherapy available to a broader group of allergic patients. In the largest clinical programme ever conducted with allergen-specific immunotherapy, over 1,700 adults and 260 children have been exposed to Grazax?. Grazax is formulated as an oral lyophilisate (tablet) for su...

  14. From Maximum Entropy to Maximum Entropy Production: A New Approach

    Directory of Open Access Journals (Sweden)

    Nathaniel Virgo

    2010-01-01

    Full Text Available Evidence from climate science suggests that a principle of maximum thermodynamic entropy production can be used to make predictions about some physical systems. I discuss the general form of this principle and an inherent problem with it, currently unsolved by theoretical approaches: how to determine which system it should be applied to. I suggest a new way to derive the principle from statistical mechanics, and present a tentative solution to the system boundary problem. I discuss the need for experimental validation of the principle, and its impact on the way we see the relationship between thermodynamics and kinetics.

  15. Uptake of Germanium and Rare Earth Elements (La, Gd, Er, Nd) by white mustard (Brassica alba L.) and common millet (Panicum milliaceum L.) as affected by Phosphorus Nutrition

    Science.gov (United States)

    Zill, Juliane; Wiche, Oliver

    2015-04-01

    The effect of phosphate nutrition is important due to the future usage of fertilizer treatment in phytomining experiments e.g. in accumulation of the economically important rare earth elements (REE). It is expected that the trivalent charge of REE will result in complexation with phosphate and REEs could be immobilized and not further bioavailable for plants which would cause losses of REE concentration in biomass. To investigate this influence on lanthanum, neodymium, gadolinium and erbium two plant species Brassica alba (white mustard) and Panicum miliaceum (common millet) were cultured in a greenhouse study. The plants were cultivated onto two different substrates and were poured with modified REE and phosphate solutions within an eight-week period. The concentrations of REE in soil, soil solution and plant samples were determined by inductively coupled plasma-mass spectrometry (ICP-MS). The results show an increase of concentration of REE with increasing levels of element solution applied for both species. REE accumulations are elevated in roots and decrease in the order of roots> leaves> stem> fruit/blossom. Brassica accumulated more REE in root whereas Panicum showed higher REE concentrations in leaves. Exposure to increased phosphate addition did not significantly change the concentrations of REE in both plant species yet the REE concentrations in leaves slightly decreased with increasing phosphate addition. For root and stem no precise trend could be determined. It is most likely that REEs precipitate with phosphate on root surfaces and in the roots. The bioavailability of REE to plants is affected by complexation processes of REEs with phosphate in the rhizosphere. The results indicate that phosphate application plays an important role on REE uptake by roots and accumulation in different parts of a plant and it might have an influence on translocation of REE within the plant.

  16. Juice-extracted grass pellets and sodium bicarbonate for cows in midlactation fed timothy grass silage.

    Science.gov (United States)

    Orozco-Hernandez, J R; Brisson, G J; Girard, V

    1994-12-01

    Eighteen midlactation Holstein cows, averaging 80 to 125 d of lactation, were used in a trial of switchback design to evaluate two timothy silages, wilted or direct-cut and treated with formic acid, and three treatments, control, NaHCO3 added at 2% of DM, or juice-extracted grass pellets replacing 30% silage DM. Cows fed direct-cut silage that had been treated with formic acid consumed more DM (19.8 vs. 18.6 kg/d) than those fed wilted silage. The DMI was also increased with NaHCO3 and grass pellet treatments. However, NaHCO3 reduced digestibility of most nutrients without affecting pH of rumen fluid or degradation of DM and NDF. Compared with wilted silage, direct-cut silage that had been treated with formic acid contained more degradable NDF (86 vs. 84.5%). Milk yield (24.9 vs. 23.6 kg/d) was higher for cows fed direct-cut than wilted silage, but 4% FCM yield remained unchanged. Addition of NaHCO3 tended to increase yields of milk and 4% FCM. Treatments did not affect milk composition. Serum urea N was higher for cows fed the direct-cut silage than for cows fed wilted silage. Silage type had more impact on feed intake and performance than did NaHCO3 or juice-extracted grass pellets.

  17. Co-digestion of manure with grass silage and pulp and paper mill sludge using nutrient additions.

    Science.gov (United States)

    Hagelqvist, Alina; Granström, Karin

    2016-08-01

    There is an increasing worldwide demand for biogas. Anaerobic co-digestion involves the treatment of different substrates with the aim of improving the production of biogas and the stability of the process. This study evaluates how methane production is affected by the co-digestion of pig and dairy manure with grass silage and pulp and paper mill sludge and assesses whether methane production is affected by factors other than nutrient deficiency, low buffering capacity, inadequate dilution, and an insufficient activity and amount of microorganism culture. Anaerobic digestion was performed in batch reactors under mesophilic conditions for 20 days. The season of grass silage and manure collection proved to be an important factor affecting methane production. Spring grass silage produced a maximum of 250 mL/VSadded and spring manure 150 mL/VSadded, whereas autumn grass silage produced at most 140 ml/VSadded and autumn manure 45 mL/VSadded. The pulp mill sludge used is comprised of both primary and secondary sludge and produced at most 50 mL/VSadded regardless of season; this substrate benefitted most from co-digestion.

  18. Epichloë grass endophytes in sustainable agriculture.

    Science.gov (United States)

    Kauppinen, Miia; Saikkonen, Kari; Helander, Marjo; Pirttilä, Anna Maria; Wäli, Piippa R

    2016-02-03

    There is an urgent need to create new solutions for sustainable agricultural practices that circumvent the heavy use of fertilizers and pesticides and increase the resilience of agricultural systems to environmental change. Beneficial microbial symbionts of plants are expected to play an important role in integrated pest management schemes over the coming decades. Epichloë endophytes, symbiotic fungi of many grass species, can protect plants against several stressors, and could therefore help to increase the productivity of forage grasses and the hardiness of turf grasses while reducing the use of synthetic pesticides. Indeed, Epichloë endophytes have successfully been developed and commercialized for agricultural use in the USA, Australia and New Zealand. Many of the host grass species originate from Europe, which is a biodiversity hotspot for both grasses and endophytes. However, intentional use of endophyte-enhanced grasses in Europe is virtually non-existent. We suggest that the diversity of European Epichloë endophytes and their host grasses should be exploited for the development of sustainable agricultural, horticultural and landscaping practices, and potentially for bioremediation and bioenergy purposes, and for environmental improvement.

  19. Generic maximum likely scale selection

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2007-01-01

    in this work is on applying this selection principle under a Brownian image model. This image model provides a simple scale invariant prior for natural images and we provide illustrative examples of the behavior of our scale estimation on such images. In these illustrative examples, estimation is based......The fundamental problem of local scale selection is addressed by means of a novel principle, which is based on maximum likelihood estimation. The principle is generally applicable to a broad variety of image models and descriptors, and provides a generic scale estimation methodology. The focus...

  20. The effects of energy grass plantations on biodiversity

    Energy Technology Data Exchange (ETDEWEB)

    Semere, T.; Slater, F.

    2005-07-01

    The ecological impact on local wildlife of biomass plantations of three different species of grasses has been monitored in the years 2002 to 2004 inclusive at farms in Herefordshire UK. Two of the grasses were not native to Britain. Wildlife monitored included ground flora, beetles, insects, birds, small mammals, butterflies, bees and hoverflies. The results provide a baseline of biodiversity data from biomass farms in England, although due to poor crop growth, the data from the switch-grass plantation was incomplete. The surveys were carried out by Cardiff University supported financially by the DTI.

  1. The effects of energy grass plantations on biodiversity

    International Nuclear Information System (INIS)

    Semere, T.; Slater, F.

    2005-01-01

    The ecological impact on local wildlife of biomass plantations of three different species of grasses has been monitored in the years 2002 to 2004 inclusive at farms in Herefordshire UK. Two of the grasses were not native to Britain. Wildlife monitored included ground flora, beetles, insects, birds, small mammals, butterflies, bees and hoverflies. The results provide a baseline of biodiversity data from biomass farms in England, although due to poor crop growth, the data from the switch-grass plantation was incomplete. The surveys were carried out by Cardiff University supported financially by the DTI

  2. Acquisition of Forgaging Skills by Lambs Eating Grass or Shrub

    OpenAIRE

    Flores, Enrique R.

    1988-01-01

    I studied the acquisition of foraging skills by lambs eating shrub or grass in three experiments. The general approach was to isolate those skills involved in prehending forage from those related to the acceptance of novel foods. Treatment lambs received 15 times more exposure to grass or shrub than did control lambs. Lambs were tested in 2.5 x 2.5 meter monocultures of shrub or grass 5 min/d, on two separate occasions. Height, bulk density and spatial arrangement of plant material were contr...

  3. Maximum-information photoelectron metrology

    Science.gov (United States)

    Hockett, P.; Lux, C.; Wollenhaupt, M.; Baumert, T.

    2015-07-01

    Photoelectron interferograms, manifested in photoelectron angular distributions (PADs), are high-information, coherent observables. In order to obtain the maximum information from angle-resolved photoionization experiments it is desirable to record the full, three-dimensional (3D), photoelectron momentum distribution. Here we apply tomographic reconstruction techniques to obtain such 3D distributions from multiphoton ionization of potassium atoms, and fully analyze the energy and angular content of the 3D data. The PADs obtained as a function of energy indicate good agreement with previous 2D data and detailed analysis [Hockett et al., Phys. Rev. Lett. 112, 223001 (2014), 10.1103/PhysRevLett.112.223001] concerning the main spectral features, but also indicate unexpected symmetry breaking in certain regions of momentum space, thus revealing additional continuum interferences which cannot otherwise be observed. These observations reflect the presence of additional ionization pathways and, most generally, illustrate the power of maximum-information measurements of coherent observables for quantum metrology of complex systems.

  4. Effect of level of lactic acid bacteria inoculant from fermented grass extract on fermentation quality of king grass silage

    Directory of Open Access Journals (Sweden)

    M.A Antaribaba

    2009-12-01

    Full Text Available Ensiling is a method of preserving moist forage based on natural fermentation where lactic acid bacteria (LAB ferment water soluble carbohydrate into organic acids mainly lactic acid under anaerobic condition. The aim of this study was to evaluate the quality of king grass (Pennisetum purpureophoides ensiled with addition of LAB prepared from fermented grass extract (LBFG. Four treatment were (G0 king grass without additive; (G1 king grass with 2% (v/w of LBFG; (G2 king grass with 3% (v/w of LBFG; (G3 king grass with 4% (v/w of LBFG. Ensiling was conducted in bottle silos of 225 g capacity at room temperatures (27.0 ± 0.20C for 30 days. The results showed that crude protein content in silage G1, G2 and G3 were relatively higher than that in silage G0. The pH value, butyric acid, total VFA and NH3-N concentrations decreased linearly with increasing level of LBFG addition, while lactic acid concentration increased linearly with LBFG addition. It was concluded that addition of 3% (v/w of LBFG resulting a better fermentation quality of king grass silage than 2% and 4% (v/w of LBFG.

  5. Changes in the concentration of grass pollen in the atmosphere of Poznań

    Directory of Open Access Journals (Sweden)

    Barbara Golińska

    2012-12-01

    Full Text Available The aim of the study was to determine the concentrations of grass pollen during the vegetation season in the atmosphere of Poznań against the background of the content of pollen of other plants and mould fungi. Observations were conducted in 1997. Concentrations of pollen grains and spores of mould fungi in the atmosphere were assessed by the volumetric method. For this purpose, the Burkard apparatus (Seven-Day Recording Volumetric Spore Trap was set up on the roof of the 8-storey high building of the Maximum College of the Agricultural University in Poznań. The continuous, 24-hour work of the apparatus made possible to monitor concentrations of allergenic pollen throughout the experiment. The tape was glued to a microscopic glass and evaluated under the light microscope. The number of pollen grains and mould spores on individual sections (2 mm per hour of the tape allowed determining their concentration per 1 m3 of air. Microscopic evaluation was conducted every 24 hours, collecting analytical material from the trap at 10 a.m. in which pollen and spores were determined. From among many wind pollinated taksons of plants, species from the grass family - because of their long period of pollination and clinical significance - play an important role in the structure of allergenic pollen in the atmosphere of Poznań. The highest concentration of grass pollen was recorded during the period from the end of May to the end of the first decade of July. From then on, the concentration of grass pollen in the air dropped rapidly and remained on a low level, not exceeding 7.5 pollen grains calculated per 1 m3 air per 24 hours. The higher concentration of grass pollen was recorded on June 29th - 360.4 grains · m-3. In terms of 24-hour period, the highest concentrations of the pollen grains in the air on a day without rain occurred between 9 and 11 a.m., whereas the lowest - at night.

  6. 238U, and its decay products, in grasses from an abandoned uranium mine

    Science.gov (United States)

    Childs, Edgar; Maskall, John; Millward, Geoffrey

    2016-04-01

    Bioaccumulation of radioactive contaminants by plants is of concern particularly where the sward is an essential part of the diet of ruminants. The abandoned South Terras uranium mine, south west England, had primary deposits of uraninite (UO2) and pitchblende (U3O8), which contained up to 30% uranium. When the mine was active uranium and radium were extracted but following closure it was abandoned without remediation. Waste rock and gangue, consisting of inefficiently processed minerals, were spread around the site, including a field where ruminants are grazed. Here we report the activity concentrations of 238U, 235U 214,210Pb, and the concentrations of selected metals in the soils, roots and leaves of grasses taken from the contaminated field. Soil samples were collected at the surface, and at 30 cm depth, using an auger along a 10-point transect in the field from the foot of a waste heap. Whole, individual grass plants were removed with a spade, ensuring that their roots were intact. The soils and roots and grass leaves were freeze-dried. Activity concentrations of the radionuclides were determined by gamma spectroscopy, following 30 days incubation for development of secular equilibrium. Dried soils, roots and grasses were also digested in aqua regia and the concentrations of elements determined by ICP techniques. Maximum activity concentrations of 238U, 235U, 214Pb and 210Pb surface soils were 63,300, 4,510, 23,300 and 49,400 Bq kg-1, respectively. The mean 238U:235U ratio was 11.8 ± 1.8, an order of magnitude lower than the natural value of 138, indicating disequilibrium within the decay chain due to mineral processing. Radionuclides in the roots had 5 times lower concentration and only grass leaves in the vicinity of the waste heap had measureable values. The mean soil to root transfer factor for 238U was 36%, the mean root to leaf was 3% and overall only 0.7% of 238U was transferred from the soil to the leaves. The roots contained 0.8% iron, possibly as

  7. System for Memorizing Maximum Values

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor)

    1996-01-01

    The invention discloses a system capable of memorizing maximum sensed values. The system includes conditioning circuitry which receives the analog output signal from a sensor transducer. The conditioning circuitry rectifies and filters the analog signal and provides an input signal to a digital driver, which may be either liner or logarithmic. The driver converts the analog signal to discrete digital values, which in turn triggers an output signal on one of a plurality of driver output lines n. The particular output lines selected is dependent on the converted digital value. A microfuse memory device connects across the driver output lines, with n segments. Each segment is associated with one driver output line, and includes a microfuse that is blown when a signal appears on the associated driver output line.

  8. Remarks on the maximum luminosity

    Science.gov (United States)

    Cardoso, Vitor; Ikeda, Taishi; Moore, Christopher J.; Yoo, Chul-Moon

    2018-04-01

    The quest for fundamental limitations on physical processes is old and venerable. Here, we investigate the maximum possible power, or luminosity, that any event can produce. We show, via full nonlinear simulations of Einstein's equations, that there exist initial conditions which give rise to arbitrarily large luminosities. However, the requirement that there is no past horizon in the spacetime seems to limit the luminosity to below the Planck value, LP=c5/G . Numerical relativity simulations of critical collapse yield the largest luminosities observed to date, ≈ 0.2 LP . We also present an analytic solution to the Einstein equations which seems to give an unboundedly large luminosity; this will guide future numerical efforts to investigate super-Planckian luminosities.

  9. Scintillation counter, maximum gamma aspect

    International Nuclear Information System (INIS)

    Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  10. Generic maximum likely scale selection

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2007-01-01

    The fundamental problem of local scale selection is addressed by means of a novel principle, which is based on maximum likelihood estimation. The principle is generally applicable to a broad variety of image models and descriptors, and provides a generic scale estimation methodology. The focus...... in this work is on applying this selection principle under a Brownian image model. This image model provides a simple scale invariant prior for natural images and we provide illustrative examples of the behavior of our scale estimation on such images. In these illustrative examples, estimation is based...... on second order moments of multiple measurements outputs at a fixed location. These measurements, which reflect local image structure, consist in the cases considered here of Gaussian derivatives taken at several scales and/or having different derivative orders....

  11. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-09-07

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  12. Brassinosteroid Mediated Cell Wall Remodeling in Grasses under Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Xiaolan Rao

    2017-05-01

    Full Text Available Unlike animals, plants, being sessile, cannot escape from exposure to severe abiotic stresses such as extreme temperature and water deficit. The dynamic structure of plant cell wall enables them to undergo compensatory changes, as well as maintain physical strength, with changing environments. Plant hormones known as brassinosteroids (BRs play a key role in determining cell wall expansion during stress responses. Cell wall deposition differs between grasses (Poaceae and dicots. Grass species include many important food, fiber, and biofuel crops. In this article, we focus on recent advances in BR-regulated cell wall biosynthesis and remodeling in response to stresses, comparing our understanding of the mechanisms in grass species with those in the more studied dicots. A more comprehensive understanding of BR-mediated changes in cell wall integrity in grass species will benefit the development of genetic tools to improve crop productivity, fiber quality and plant biomass recalcitrance.

  13. Seasonal variation in diurnal atmospheric grass pollen concentration profiles

    DEFF Research Database (Denmark)

    Peel, Robert George; Orby, P.V.; Skjoth, C. A.

    2014-01-01

    In this study, the diurnal atmospheric grass pollen concentration profile within the Danish city of Aarhus was shown to change in a systematic manner as the pollen season progressed. Although diurnal grass pollen profiles can differ greatly from day-to-day, it is common practice to establish...... the time of day when peak concentrations are most likely to occur using seasonally averaged diurnal profiles. Atmospheric pollen loads are highly dependent upon emissions, and different species of grass are known to flower and emit pollen at different times of the day and during different periods...... of the pollen season. Pollen concentrations are also influenced by meteorological factors - directly through those parameters that govern pollen dispersion and transport, and indirectly through the weather-driven flowering process. We found that three different profiles dominated the grass pollen season...

  14. Variation in important pasture grasses: I. Morphological and ...

    African Journals Online (AJOL)

    Language: English. Keywords: cenchrus ciliaris; cynodon dactylon; digitaria eriantha; distribution; ecotypes; environmental conditions; eragrostis curvula; geographical distribution; Geography; grasses; heteropogon contortus; morphological variation; Morphology; natal; northern cape; orange free state; pasture; pasture ...

  15. Study of the organic -15N mineralization in an Oxisol and its absorption by a grass (Melinis minutiflora Beauv.)

    International Nuclear Information System (INIS)

    Urquiaga C, S.; Libardi, P.L.; Reichardt, K.; Padovese, P.P.; Moraes, S.O.; Victoria, R.L.

    1982-01-01

    Mineralization of organic-N to soil samples of an Oxisol as 15 N-labeled bean straw, with and without N from fertilizer (urea) was studied, as well as the effect of expanded vermiculite in the production and absorption of the mineralized-N by a grass. The experiment was conducted in plastic pots. The fertilizer urea (46,64%N) utilized was labelled (5,2% of 15 N) atoms). All experimental pots received 150 ppm of P and K as simple superphosphate (18% P 2 O 5 ) and 26% CaO) and potassium sulphate (60% K 2 O), respectively. The grass was planted by putting 8 small pieces by pot. The aerial part was harvested at 30 days intervals. Grass production was a function of the N available and bean straw behaved as an important N source for the plants; at 30 days (first sampling) the production N extraction and efficiency of utilization of the organic N were at their maximum, decreasing (p=0,01) at each following harvest; after the first sampling the mineralization rate of organic N was very low, decreasing significantly the grass production; N fertilizer favoured significantly the mineralization and the efficiency of utilization of the organic-N applied; vermiculite did not affect either production or the N extraction by the grass; in the soil mineral-N, after the culture, the percentage of N from labelled sources was two times that of the total-N and lower than in the plant in the final harvest. (Author) [pt

  16. Nitrogen availability from composts for humid region perennial grass and legume-grass forage production.

    Science.gov (United States)

    Lynch, D H; Voroney, R P; Warman, P R

    2004-01-01

    Perennial forages may be ideally suited for fertilization with slow N release amendments such as composts, but difficulties in predicting N supply from composts have limited their routine use in forage production. A field study was conducted to compare the yield and protein content of a binary legume-grass forage mixture and a grass monocrop cut twice annually, when fertilized with diverse composts. In all three years from 1998-2000, timothy (Phleum pratense L.)-red clover (Trifolium pratense L.) and timothy swards were fertilized with ammonium nitrate (AN) at up to 150 and 300 kg N ha(-1) yr(-1), respectively. Organic amendments, applied at up to 600 kg N ha(-1) yr(-1) in the first two years only, included composts derived from crop residue (CSC), dairy manure (DMC), or sewage sludge (SSLC), plus liquid dairy manure (DM). Treatments DM at 150 kg N ha(-1) yr(-1) and CSC at 600 kg N ha(-1) yr(-1) produced cumulative timothy yields matching those obtained for inorganic fertilizer. Apparent nitrogen recovery (ANR) ranged from 0.65% (SSLC) to 15.1% (DMC) for composts, compared with 29.4% (DM) and 36.5% (AN). The legume component (approximately 30%) of the binary mixture acted as an effective "N buffer" maintaining forage yield and protein content consistently higher, and within a narrower range, across all treatments. Integrating compost utilization into livestock systems that use legume-grass mixtures may reduce the risk of large excesses or deficits of N, moderate against potential losses in crop yield and quality, and by accommodating lower application rates of composts, reduce soil P and K accumulation.

  17. Sonoran Desert ecosystem transformation by a C4 grass without the grass/fire cycle

    Science.gov (United States)

    Olsson, Aaryn D.; Betancourt, Julio; McClaran, Mitchel P.; Marsh, Stuart E.

    2012-01-01

    Aim Biological invasions facilitate ecosystem transformation by altering the structure and function, diversity, dominance and disturbance regimes. A classic case is the grass–fire cycle in which grass invasion increases the frequency, scale and/or intensity of wildfires and promotes the continued invasion of invasive grasses. Despite wide acceptance of the grass–fire cycle, questions linger about the relative roles that interspecific plant competition and fire play in ecosystem transformations. Location Sonoran Desert Arizona Upland of the Santa Catalina Mountains, Arizona, USA. Methods We measured species cover, density and saguaro (Carnegiea gigantea) size structure along gradients of Pennisetum ciliare invasion at 10 unburned/ungrazed P. ciliare patches. Regression models quantified differences in diversity, cover and density with respect to P. ciliare cover, and residence time and a Fisher's exact test detected demographic changes in saguaro populations. Because P. ciliare may have initially invaded locations that were both more invasible and less diverse, we ran analyses with and without the plots in which initial infestations were located. Results Richness and diversity decreased with P. ciliare cover as did cover and density of most dominant species. Richness and diversity declined with increasing time since invasion, suggesting an ongoing transformation. The proportion of old-to-young Carnegiea gigantea was significantly lower in plots with dominant P. ciliare cover. Main conclusions Rich desert scrub (15–25 species per plot) was transformed into depauperate grassland (2–5 species per plot) within 20 years following P. ciliare invasion without changes to the fire regime. While the onset of a grass–fire cycle may drive ecosystem change in the later stages and larger scales of grass invasions of arid lands, competition by P. ciliare can drive small-scale transformations earlier in the invasion. Linking competition-induced transformation rates with

  18. Grass buffers for playas in agricultural landscapes: An annotated bibliography

    Science.gov (United States)

    Melcher, Cynthia P.; Skagen, Susan K.

    2005-01-01

    This bibliography and associated literature synthesis (Melcher and Skagen, 2005) was developed for the Playa Lakes Joint Venture (PLJV). The PLJV sought compilation and annotation of the literature on grass buffers for protecting playas from runoff containing sediments, nutrients, pesticides, and other contaminants. In addition, PLJV sought information regarding the extent to which buffers may attenuate the precipitation runoff needed to fill playas, and avian use of buffers. We emphasize grass buffers, but we also provide information on other buffer types.

  19. A novel method to characterize silica bodies in grasses

    OpenAIRE

    Dabney, Clemon; Ostergaard, Jason; Watkins, Eric; Chen, Changbin

    2016-01-01

    Background The deposition of silicon into epidermal cells of grass species is thought to be an important mechanism that plants use as a defense against pests and environmental stresses. There are a number of techniques available to study the size, density and distribution pattern of silica bodies in grass leaves. However, none of those techniques can provide a high-throughput analysis, especially for a great number of samples. Results We developed a method utilizing the autofluorescence of si...

  20. KARTAWINATA et al: Grass communities on Oahu

    Directory of Open Access Journals (Sweden)

    " "

    1972-06-01

    Full Text Available For the windward group, there was a significant correlation (TableV only between the amount of rainfall and the order of the plots on theX-axis. It has been shown in the ordination diagram (Fig. 4 that threecommunity types can be recognized, the Rhynchelytrum repens, Melinisminutiflora and Andropogon virginicus community types. The relationshipbetween the change of the grass dominance and the rainfall gradient alongthe X- axis is shown in Fig. 9. In this diagram the X-axis was dividedinto ten segments: 0.0 — 9.9; 10.0 — 19.9; 20.0 — 29.9; 30.0 — 39.9;40.0 — 49.9; 50.0 — 59.9; 60.0 — 69.9; 70.0 — 79.9; 80.0 — 89.9 and90.0 — 100.0. The intervals 20.0 — 39.9 and 50.0 — 69.9 were consideredas individual units because there was only one plot in the intervals20.0 — 29.9 and 50.0 — 59.9, respectively.

  1. Biomass of elephant grass and leucaena for bioenergy production

    Directory of Open Access Journals (Sweden)

    Fernanda Aparecida Sales

    2015-12-01

    Full Text Available The objective of this study was to evaluate the biomass production of elephant grass and leucaena in Paraná state, Brazil, for the generation of renewable energy. Two field studies were conducted in the municipality of Ibiporã (23° S, 51° 01?W. In the first study, the dry matter accumulation curves were calculated, with sampling at 30, 60, 90, 120, and 180 days after cultivation. The second study was conducted in a randomized complete block design with split plots. The total aboveground biomass production of elephant grass and leucaena was estimated in the main plot. Cutting times of 60 and 120 days after cultivation were evaluated in the subplots. The productivity of dry matter (kg.ha-1 was estimated using the biomass data. In addition, the potential production of energy from the burning of elephant grass biomass, and the potential production of total aboveground biomass and energy of elephant grass (in Paraná was estimated using an agrometeorological model. Elephant grass can be potentially used as an alternative energy source. Leucaena has slow initial growth, and it must therefore be evaluated over a longer period in order to determine its potential. Simulation analyses of the capability of power generation, conducted based on the annual dry matter production, revealed that elephant grass could be an important source of renewable energy in the state of Paraná.

  2. Synergism of Wild Grass and Hydrocarbonoclastic Bacteria in Petroleum Biodegradation

    Directory of Open Access Journals (Sweden)

    Nuni Gofar

    2013-05-01

    Full Text Available The concept of plants and microbes utilization for remediation measure of pollutant contaminated soil is the newest development in term of petroleum waste management technique. The research objective was to obtain wild grass types and hydrocarbonoclastic bacteria which are capable to synergize in decreasing petroleum concentration within petroleum contaminated soil. This research was conducted in a factorial by using a randomized completely block design. The first factor was wild grass type which were without plant, Tridax procumbens grass and Lepironia mucronata grass. The second factor was hydrocarbonoclastic bacteria type which were without bacterium, single bacterium of Alcaligenes faecalis, single bacterium of Pseudomonas alcaligenes, and mixed bacteria of Alcaligenes faecalis with P. alcaligenes. The results showed that mixed bacteria (A. faecalis and P. alcaligenes were capable to increase the crown and roots dry weights of these two grasses and bacteria population, decreased percentage of TPH (total petroleum hydrocarbon and had better pH value than that of single bacterium. The highest TPH decrease with magnitude of 70.1% was obtained on the treatment of L. mucronata grass in combination with mixed bacteria.

  3. The effect of mulching and fertilising on growth of over-sown grass ...

    African Journals Online (AJOL)

    ... Ischaemum afrum and Tragus berteronianus) and imported seeds of three additional species (Cenchrus ciliaris, Chloris gayana and Panicum coloratum) were oversown in a severely degraded area of the rangeland to improve cover and grazing capacity of the rangeland. The effect of combinations of inorganic fertiliser, ...

  4. Post-treatment efficacy of discontinuous treatment with 300IR 5-grass pollen sublingual tablet in adults with grass pollen-induced allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Didier, A; Malling, H-J; Worm, Marcel

    2013-01-01

    Sustained efficacy over three pollen seasons of pre- and co-seasonal treatment with 300IR 5-grass pollen sublingual tablet has been demonstrated in adults with moderate-severe grass pollen-associated allergic rhinoconjunctivitis....

  5. Maximum entropy and Bayesian methods

    International Nuclear Information System (INIS)

    Smith, C.R.; Erickson, G.J.; Neudorfer, P.O.

    1992-01-01

    Bayesian probability theory and Maximum Entropy methods are at the core of a new view of scientific inference. These 'new' ideas, along with the revolution in computational methods afforded by modern computers allow astronomers, electrical engineers, image processors of any type, NMR chemists and physicists, and anyone at all who has to deal with incomplete and noisy data, to take advantage of methods that, in the past, have been applied only in some areas of theoretical physics. The title workshops have been the focus of a group of researchers from many different fields, and this diversity is evident in this book. There are tutorial and theoretical papers, and applications in a very wide variety of fields. Almost any instance of dealing with incomplete and noisy data can be usefully treated by these methods, and many areas of theoretical research are being enhanced by the thoughtful application of Bayes' theorem. Contributions contained in this volume present a state-of-the-art overview that will be influential and useful for many years to come

  6. Serodiagnosis of grass carp reovirus infection in grass carp Ctenopharyngodon idella by a novel Western blot technique.

    Science.gov (United States)

    He, Yongxing; Jiang, Yousheng; Lu, Liqun

    2013-12-01

    Frequent outbreaks of grass carp hemorrhagic disease, caused by grass carp reovirus (GCRV) infection, pose as serious threats to the production of grass carp Ctenopharyngodon idella. Although various nucleic acids-based diagnostic methods have been shown effective, lack of commercial monoclonal antibody against grass carp IgM has impeded the development of any reliable immunoassays in detection of GCRV infection. The present study describes the preparation and screening of monoclonal antibodies against the constant region of grass carp IgM protein, and the development of a Western blot (WB) protocol for the specific detection of antibodies against outer capsid VP7 protein of GCRV that serves as antibody-capture antigen in the immunoassay. In comparison to a conventional RT-PCR method, validity of the WB is further demonstrated by testing on clinical fish serum samples collected from a grass carp farm in Jiangxi Province during disease pandemic in 2011. In conclusion, the WB technique established in this study could be employed for specific serodiagnosis of GCRV infection. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Preliminary Results of Clover and Grass Coverage and Total Dry Matter Estimation in Clover-Grass Crops Using Image Analysis

    Directory of Open Access Journals (Sweden)

    Anders K. Mortensen

    2017-12-01

    Full Text Available The clover-grass ratio is an important factor in composing feed ratios for livestock. Cameras in the field allow the user to estimate the clover-grass ratio using image analysis; however, current methods assume the total dry matter is known. This paper presents the preliminary results of an image analysis method for non-destructively estimating the total dry matter of clover-grass. The presented method includes three steps: (1 classification of image illumination using a histogram of the difference in excess green and excess red; (2 segmentation of clover and grass using edge detection and morphology; and (3 estimation of total dry matter using grass coverage derived from the segmentation and climate parameters. The method was developed and evaluated on images captured in a clover-grass plot experiment during the spring growing season. The preliminary results are promising and show a high correlation between the image-based total dry matter estimate and the harvested dry matter ( R 2 = 0.93 with an RMSE of 210 kg ha − 1 .

  8. PRODUKSI DAN KUALITAS HIJAUAN PAKAN PADA LAHAN PASCA TAMBANG DI KABUPATEN KARANGASEM

    Directory of Open Access Journals (Sweden)

    I Wayan Suarna

    2015-06-01

    Full Text Available The side-effect of sand mining was disappearing of biomass which caused of land degradation. A study has been carried out to obtain the model legume association with superior grass plants that are adaptive to repair post-mining land on dry land. This research was desgined in association patern between grasses and legumes with manure application, using 8 combination of grasses herbaceous and tree legumse with 3 replications. This research was conducted at Sebudi village, Karangasem district. Panicum maximum var. Trichoglum, Paspalum atratum, Centrocema pubescens, and Clitoria ternatea were used for grasses and legumes respectively. Observed variables were quality and forage production. The results of this research showed that almost all association can be implemented at dryland, and association patern between Panicum and Paspalum with Clitoria gave extra biomass. This association also showed great potential to improve land quality. The quality and production of grasses were greatly influenced by the association of legumes. Panicum and Paspalum associated with both Clitoria or Centrocema gave highest yield. Various of manure showed a non significant difference on quality and production of grass associated with tree legumes, although it tend to increase both of growth and production of grasses.

  9. Efectos del forraje diferido como cobertura de invierno en el crecimiento primaveral de las gramíneas tropicales Chloris gayana y Panicum coloratum

    Directory of Open Access Journals (Sweden)

    José A. Imaz

    2017-01-01

    Full Text Available En La Plata, Buenos Aires, Argentina, en un experimento en macetas a aire libre (condiciones de luz y temperatura naturales se evaluó el efecto del forraje diferido como cobertura invernal en 2 gramíneas tropicales C4 (Chloris gayana y Panicum coloratum. Plantas adultas fueron extraídas de un establecimiento ganadero, trasplantadas a macetas en un jardín experimental y después de crecer durante 111 días (2 de Febrero al 23 de Mayo sometidas a los tratamientos: (1 control [sin remoción del forraje diferido de otoño (DF]; y (2 remoción del forraje diferido de otoño (DFR a 15 cm del suelo. Se utilizaron 10 repeticiones por tratamiento y una planta por maceta (unidad experimental. Las plantas fueron cosechadas el 27 de Septiembre (después del invierno y nuevamente en Noviembre para medir la biomasa del rebrote primaveral en los estratos superior (>15 cm e inferior (<15 cm sobre el suelo, láminas, vainas y estolones. Se realizó un análisis alométrico para dilucidar la incidencia del estrés por frio y se registraron la temperatura del aire, la humedad relativa y la ocurrencia de heladas. Las plantas con forraje diferido alcanzaron una mayor biomasa (55‒80% que aquellas con remoción del forraje. Panicum coloratum mostró un ajuste significativo entre la biomasa total y la biomasa de los diferentes estratos para ambos tratamientos, mostrando buena tolerancia al estrés por frio. Por otro lado, C. gayana mostró  falta de ajuste de la biomasa y un mayor estrés por la remoción del forraje, mientras que las plantas sin remoción presentaron menor daño por frío y un mayor ajuste. La cobertura invernal del forraje diferido podría mejorar la productividad y supervivencia de estas especies forrajeras cuando son utilizadas en sistemas pastoriles templados. Estos resultados preliminares deben ser evaluados en condiciones de campo durante un mayor número de años, considerando diferentes estrategias de pastoreo. Palabras clave: Cobertura

  10. Upgraded fuel from reed canary grass

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, V.P.

    1995-12-31

    The feasibility of RCG for commercial utilization depends primarily on its applicability for pulp production and its use in energy production will be based on the residue that will be available after extracting the pulp fraction of the RCG. Roughly 20 ..30% of the material will be available for energy production purposes. However, the percentage may be higher/lower depending on the quality standards of the pulp fiber material. The harvesting period has a significant effect on the fuel characteristics of RCG. For instance the contents of N, S, Cl, K are clearly lower if the RCG is harvested in the spring (delayed) instead of summer/autumn. These elements affect significantly overall emission formation and ash behaviour and its melting temperature. The combustion related research in this project has been focused on the spring-harvested RCG. The project aims to evaluate the feasibility of delayed harvested RCG for energy production. In order to reach this goal, the following combustion methods will be tested and studied: combustion of pelletized RCG; gasification; combustion of pulverized RCG. In addition, pelletizing, reactivity and NO conversion of pulverized RCG will be studied. The research described here is a part of `Reed Canary Grass` project (in AIR programme). The contractors of the project are Swedish University of Agricultural Sciences (coordinator), United Milling Systems from Denmark, Jaakko Poeyry Oy and VTT Energy. In addition, there are partners from several countries participating in the project. The project has been divided in five tasks, VTT Energy being responsible for combustion related task `Upgraded fuel` that includes the research topics discussed in this paper

  11. A 250 plastome phylogeny of the grass family (Poaceae): topological support under different data partitions

    Science.gov (United States)

    Burke, Sean V.; Wysocki, William P.; Clark, Lynn G.

    2018-01-01

    The systematics of grasses has advanced through applications of plastome phylogenomics, although studies have been largely limited to subfamilies or other subgroups of Poaceae. Here we present a plastome phylogenomic analysis of 250 complete plastomes (179 genera) sampled from 44 of the 52 tribes of Poaceae. Plastome sequences were determined from high throughput sequencing libraries and the assemblies represent over 28.7 Mbases of sequence data. Phylogenetic signal was characterized in 14 partitions, including (1) complete plastomes; (2) protein coding regions; (3) noncoding regions; and (4) three loci commonly used in single and multi-gene studies of grasses. Each of the four main partitions was further refined, alternatively including or excluding positively selected codons and also the gaps introduced by the alignment. All 76 protein coding plastome loci were found to be predominantly under purifying selection, but specific codons were found to be under positive selection in 65 loci. The loci that have been widely used in multi-gene phylogenetic studies had among the highest proportions of positively selected codons, suggesting caution in the interpretation of these earlier results. Plastome phylogenomic analyses confirmed the backbone topology for Poaceae with maximum bootstrap support (BP). Among the 14 analyses, 82 clades out of 309 resolved were maximally supported in all trees. Analyses of newly sequenced plastomes were in agreement with current classifications. Five of seven partitions in which alignment gaps were removed retrieved Panicoideae as sister to the remaining PACMAD subfamilies. Alternative topologies were recovered in trees from partitions that included alignment gaps. This suggests that ambiguities in aligning these uncertain regions might introduce a false signal. Resolution of these and other critical branch points in the phylogeny of Poaceae will help to better understand the selective forces that drove the radiation of the BOP and PACMAD

  12. GRASS GIS: The first Open Source Temporal GIS

    Science.gov (United States)

    Gebbert, Sören; Leppelt, Thomas

    2015-04-01

    GRASS GIS is a full featured, general purpose Open Source geographic information system (GIS) with raster, 3D raster and vector processing support[1]. Recently, time was introduced as a new dimension that transformed GRASS GIS into the first Open Source temporal GIS with comprehensive spatio-temporal analysis, processing and visualization capabilities[2]. New spatio-temporal data types were introduced in GRASS GIS version 7, to manage raster, 3D raster and vector time series. These new data types are called space time datasets. They are designed to efficiently handle hundreds of thousands of time stamped raster, 3D raster and vector map layers of any size. Time stamps can be defined as time intervals or time instances in Gregorian calendar time or relative time. Space time datasets are simplifying the processing and analysis of large time series in GRASS GIS, since these new data types are used as input and output parameter in temporal modules. The handling of space time datasets is therefore equal to the handling of raster, 3D raster and vector map layers in GRASS GIS. A new dedicated Python library, the GRASS GIS Temporal Framework, was designed to implement the spatio-temporal data types and their management. The framework provides the functionality to efficiently handle hundreds of thousands of time stamped map layers and their spatio-temporal topological relations. The framework supports reasoning based on the temporal granularity of space time datasets as well as their temporal topology. It was designed in conjunction with the PyGRASS [3] library to support parallel processing of large datasets, that has a long tradition in GRASS GIS [4,5]. We will present a subset of more than 40 temporal modules that were implemented based on the GRASS GIS Temporal Framework, PyGRASS and the GRASS GIS Python scripting library. These modules provide a comprehensive temporal GIS tool set. The functionality range from space time dataset and time stamped map layer management

  13. Calculation of Spotting Particles Maximum Distance in Idealised Forest Fire Scenarios

    Directory of Open Access Journals (Sweden)

    José C. F. Pereira

    2015-01-01

    Full Text Available Large eddy simulation of the wind surface layer above and within vegetation was conducted in the presence of an idealised forest fire by using an equivalent volumetric heat source. Firebrand’s particles are represented as spherical particles with a wide range of sizes, which were located into the combustion volume in a random fashion and are convected in the ascending plume as Lagrangian points. The thermally thin particles undergo drag relative to the flow and moisture loss as they are dried and pyrolysis, char-combustion, and mass loss as they burn. The particle momentum, heat and mass transfer, and combustion governing equations were computed along particle trajectories in the unsteady 3D wind field until their deposition on the ground. The spotting distances are compared with the maximum spotting distance obtained with Albini model for several idealised line grass or torching trees fires scenarios. The prediction of the particle maximum spotting distance for a 2000 kW/m short grass fire compared satisfactorily with results from Albini model and underpredicted by 40% the results for a high intensity 50000 kW/m fire. For the cases of single and four torching trees the model predicts the maximum distances consistently but for slightly different particle diameter.

  14. Seleção entre e dentro de famílias e seleção combinada em famílias de meio-irmãos de Panicum maximum Jacq.

    OpenAIRE

    Martuscello, Janaina Azevedo; Jank, Liana; Fonseca, Dilermando Miranda da; Cruz, Cosme Damião; Cunha, Daniel de Noronha Figueiredo Vieira da

    2009-01-01

    The objective of this study was to select superior genotypes in half-sib populations obtained from crosses between sexual plants and apomictic accessions. The experiment also proposed to compare among and within family and combined selection strategies. Ten plots of sexual plants were randomly distributed among 230 plots of apomictic accessions. After natural pollination, seeds of each sexual plant constituted a half-sib family. Thirty plants of each female progenitor were evaluated in a rand...

  15. Degradabilidad ruminal in vitro de ensilajes de pasto saboya (Panicum maximum jacq. con diferentes niveles de inclusión de cáscara de maracuyá (Passiflora edulis sims.

    Directory of Open Access Journals (Sweden)

    Alexandra Barrera-Álvarez

    2017-12-01

    Full Text Available La investigación tuvo como objetivo evaluar la composición y degradabilidad ruminal in vitro de la materia seca, materia orgánica y materia inorgánica de los ensilajes de pasto saboya con los tratamientos T1: Pasto saboya 90%+cáscara de maracuyá 10%; T2: Pasto saboya 80%+cáscara de maracuyá 20%; T3: Pasto saboya 70%+cáscara de maracuyá 30% y T4: Pasto saboya 60%+cáscara de maracuyá 40%. Se utilizó el método de microensilaje (silos PVC de 3 kg de capacidad provistos de una válvula bunsen y mecanismo de extracción de efluentes y la técnica de degradación in vitro con el sistema de incubación DAISY II, empleando el líquido ruminal de bovinos brahman de 500±25 kg de peso promedio. Se aplicó un Diseño Completamente al Azar con seis repeticiones. El nivel de inclusión de maracuyá mejoró el contenido de nutrientes en el ensilaje, incrementando la materia orgánica, la proteína bruta y la grasa bruta y disminuyendo las fracciones de fibra. La degradabilidad de la materia seca, materia orgánica y materia inorgánica fue superior (p

  16. Características Morfogênicas e Acúmulo de Forragem do Capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia em Dois Resíduos Forrageiros Pós-Pastejo

    Directory of Open Access Journals (Sweden)

    Barbosa Rodrigo Amorim

    2002-01-01

    Full Text Available O experimento foi conduzido no Centro Nacional de Gado de Corte da Empresa Brasileira de Pesquisa Agropecuária (Embrapa Gado de Corte. Foram avaliadas as características morfogênicas de folhas e perfilhos, acúmulo de matéria seca verde e índices de crescimento do capim-tanzânia em dois resíduos forrageiros pós-pastejo (Resíduo alto -- RA 3,6 t de MS/ha e Resíduo baixo -- RB 2,3 t de MS/ha, até os 35 dias após o pastejo. O delineamento experimental foi em blocos casualizados completos com os tratamentos no esquema de parcelas subdivididas com três repetições. Para a dinâmica de perfilhamento houve diferença entre resíduos somente no aparecimento de novos perfilhos basilares. A taxa de aparecimento de novos perfilhos, tanto basilares quanto aéreos, decresceu linearmente com os dias de rebrotação após o pastejo. As taxas de alongamento e senescência de folhas não diferiram entre resíduos e tipos de perfilho. Em contrapartida, a duração de alongamento foliar foi menor no resíduo baixo e no perfilho novo, porém produzindo folhas com menor comprimento final. Houve interação entre resíduo e tipo de perfilho para a taxa de aparecimento de folhas, com maiores valores para o resíduo baixo no perfilho novo e remanescente. O acúmulo de matéria seca verde não diferiu entre resíduos, sendo, em média, 61,4 e 47,9 kg/ha.dia, nos resíduos baixo e alto, respectivamente. A taxa de crescimento relativo e o índice de área foliar não apresentaram diferenças entre resíduos forrageiros, porém apresentaram comportamento inverso em função dos dias após o pastejo.

  17. PRODUKSI BIOMASSA DAN NILAI NUTRISI RUMPUT PAKAN PADA TANAH DENGAN TINGKAT SALINITAS BERBEDA

    Directory of Open Access Journals (Sweden)

    Kusmiyati F

    2014-06-01

    Full Text Available Salt from sea water can ingress through groundwater, rivers and estuaries that cause large areas of salt-affected soils. The presence of excess salts on the soil surface and in the root zone inhibits crop growth and production. An electrical conductivity of the saturation soil extract at saline soil is more than 4 dS/m. A experiment was conducted to identify potentially suitable forage grasses for growing at saline soil Five forage grasses were tested in greenhouse. They were Panicum maximum, Setaria sphacelata, Euchlaena mexicana, Brachiaria brizantha, and Cynodon plectostachyus. Grasses were planted at non-saline soil (EC = 0.5 dS/m and saline soil (EC = 11 dS/m. Biomass yield and nutritional value of grasses were evaluated. Biomass yield (fresh and dry matter of shoot and root was significantly reduced at saline soil compared with non-saline soil. Ranking of forages according to the percent reduction in biomass yield due to the higher level of salinity was Brachiaria brizantha > Euchlaena mexicana > Panicum maximum > Cynodon plectostachyus > Setaria sphacelata. Crude protein percentage of Brachiaria brizantha was significantly lower at saline soil compared with non saline soil. While there were no significantly different of crude protein between non-saline soil and saline soil of Panicum maximum, Setaria sphacelata, Euchlaena mexicana and Cynodon plectostachyus. Acid detergent fiber and neutral detergent fiber of Brachiaria brizantha were significantly higher at saline soil. So, Brachiaria brizantha was judged as the worst species in terms of biomass yield and nutritional value. Although, the percentage reduction biomass yield of Cynodon plectostachyus at saline soil was low, Cynodon plectostachyus was judged to be unacceptable because of its poor nutritional value and low production. Euchlaena mexicana had lower biomass at saline soil, also it had lower nutritional value compared with Panicum maximum. In conclusion, based on biomass yield

  18. How much gas can we get from grass?

    International Nuclear Information System (INIS)

    Nizami, A.S.; Orozco, A.; Groom, E.; Dieterich, B.; Murphy, J.D.

    2012-01-01

    Highlights: ► We highlight the various results for biomethane potential that may be obtained from the same grass silage. ► The results indicated that methane potential varied from 350 to 493 L CH 4 kg −1 VS added for three different BMP procedures. ► We compare two distinct digestion systems using the same grass. ► A two stage wet system achieved 451 L CH 4 kg −1 VS added over a 50 day retention period. ► A two phase system achieved 341 L CH 4 kg −1 VS added at a 30 day retention time. -- Abstract: Grass biomethane has been shown to be a sustainable gaseous transport biofuel, with a good energy balance, and significant potential for economic viability. Of issue for the designer is the variation in characteristics of the grass depending on location of source, time of cut and species. Further confusion arises from the biomethane potential tests (BMP) which have a tendency to give varying results. This paper has dual ambitions. One of these is to highlight the various results for biomethane potential that may be obtained from the same grass silage. The results indicated that methane potential from the same grass silage varied from 350 to 493 L CH 4 kg −1 VS added for three different BMP procedures. The second ambition is to attempt to compare two distinct digestion systems again using the same grass: a two stage continuously stirred tank reactor (CSTR); and a sequentially fed leach bed reactor connected to an upflow anaerobic sludge blanket (SLBR–UASB). The two engineered systems were designed, fabricated, commissioned and operated at small pilot scale until stable optimal operating conditions were reached. The CSTR system achieved 451 L CH 4 kg −1 VS added over a 50 day retention period. The SLBR–UASB achieved 341 L CH 4 kg −1 VS added at a 30 day retention time.

  19. Crop-associated virus reduces the rooting depth of non-crop perennial native grass more than non-crop-associated virus with known viral suppressor of RNA silencing (VSR).

    Science.gov (United States)

    Malmstrom, Carolyn M; Bigelow, Patrick; Trębicki, Piotr; Busch, Anna K; Friel, Colleen; Cole, Ellen; Abdel-Azim, Heba; Phillippo, Colin; Alexander, Helen M

    2017-09-15

    As agricultural acreage expanded and came to dominate landscapes across the world, viruses gained opportunities to move between crop and wild native plants. In the Midwestern USA, virus exchange currently occurs between widespread annual Poaceae crops and remnant native perennial prairie grasses now under consideration as bioenergy feedstocks. In this region, the common aphid species Rhopalosiphum padi L. (the bird cherry-oat aphid) transmits several virus species in the family Luteoviridae, including Barley yellow dwarf virus (BYDV-PAV, genus Luteovirus) and Cereal yellow dwarf virus (CYDV-RPV and -RPS, genus Polerovirus). The yellow dwarf virus (YDV) species in these two genera share genetic similarities in their 3'-ends, but diverge in the 5'-regions. Most notably, CYDVs encode a P0 viral suppressor of RNA silencing (VSR) absent in BYDV-PAV. Because BYDV-PAV has been reported more frequently in annual cereals and CYDVs in perennial non-crop grasses, we examine the hypothesis that the viruses' genetic differences reflect different affinities for crop and non-crop hosts. Specifically, we ask (i) whether CYDVs might persist within and affect a native non-crop grass more strongly than BYDV-PAV, on the grounds that the polerovirus VSR could better moderate the defenses of a well-defended perennial, and (ii) whether the opposite pattern of effects might occur in a less defended annual crop. Because previous work found that the VSR of CYDV-RPS possessed greater silencing suppressor efficiency than that of CYDV-RPV, we further explored (iii) whether a novel grass-associated CYDV-RPS isolate would influence a native non-crop grass more strongly than a comparable CYDV-RPV isolate. In growth chamber studies, we found support for this hypothesis: only grass-associated CYDV-RPS stunted the shoots and crowns of Panicum virgatum L. (switchgrass), a perennial native North American prairie grass, whereas crop-associated BYDV-PAV (and coinfection with BYDV-PAV and CYDV-RPS) most

  20. Natural geo-composites for grassing of eroded and degraded lands

    Directory of Open Access Journals (Sweden)

    Kroumov Victor

    2009-01-01

    Full Text Available Original, natural grass geocomposites (sods were developed on the basis of combination from unstuffy, needle-drive textile material, geo-net and soil-manure-peat or peat with grass cover from grass mixtures. The natural grass geocomposites have the next priorities: quickly grassing and reinforcing of eroded and degraded terrains; large uniformity and compactness of grass cove; long exploiting period; grassing of terrains with big slopes where the mechanization is difficult to use; the articles are with low mass, small thickness and high stability; they limit the growing of weed. The natural grass geocomposites are intend for control of soil erosion and reconstruction of natural landshaft. They can to reinforce ditches, grass collectors, side of the road slopes, as well as lay out lawn, parks, stadiums, ski racing tourist's beauty spot, etc.

  1. Maximum Parsimony on Phylogenetic networks

    Science.gov (United States)

    2012-01-01

    Background Phylogenetic networks are generalizations of phylogenetic trees, that are used to model evolutionary events in various contexts. Several different methods and criteria have been introduced for reconstructing phylogenetic trees. Maximum Parsimony is a character-based approach that infers a phylogenetic tree by minimizing the total number of evolutionary steps required to explain a given set of data assigned on the leaves. Exact solutions for optimizing parsimony scores on phylogenetic trees have been introduced in the past. Results In this paper, we define the parsimony score on networks as the sum of the substitution costs along all the edges of the network; and show that certain well-known algorithms that calculate the optimum parsimony score on trees, such as Sankoff and Fitch algorithms extend naturally for networks, barring conflicting assignments at the reticulate vertices. We provide heuristics for finding the optimum parsimony scores on networks. Our algorithms can be applied for any cost matrix that may contain unequal substitution costs of transforming between different characters along different edges of the network. We analyzed this for experimental data on 10 leaves or fewer with at most 2 reticulations and found that for almost all networks, the bounds returned by the heuristics matched with the exhaustively determined optimum parsimony scores. Conclusion The parsimony score we define here does not directly reflect the cost of the best tree in the network that displays the evolution of the character. However, when searching for the most parsimonious network that describes a collection of characters, it becomes necessary to add additional cost considerations to prefer simpler structures, such as trees over networks. The parsimony score on a network that we describe here takes into account the substitution costs along the additional edges incident on each reticulate vertex, in addition to the substitution costs along the other edges which are

  2. Dry matter losses of grass, lucerne and maize silages in bunker silos

    Directory of Open Access Journals (Sweden)

    Brigitte Koehler

    2013-03-01

    Full Text Available An efficient feed management is important for a sustainable and economic agricultural production. One of the main points for improving the efficiency is the reduction of feed losses. In the present investigation the dry matter (DM losses of grass, lucerne and maize silages in farm scaled bunker silos were analysed. The method of determining DM losses was the total-in versus total-out DM mass flow of the silos, including the determination of DM content and other silage parameters via manual sampling. The results taken from 48 silos showed on average for all investigated crops 9–12% of DM losses. Density and feed out rate showed a negative correlation to DM losses in maize silages. According to the applied method for determining DM losses on farm scale, a guideline of 8% can be suggested for maximum DM losses in bunker silos for grass and maize silages. The described method seems to be applicable for improving the feed management by using largely automated measurements on the harvest and feeding side.

  3. Results from the 5-year SQ grass sublingual immunotherapy tablet asthma prevention (GAP) trial in children with grass pollen allergy.

    Science.gov (United States)

    Valovirta, Erkka; Petersen, Thomas H; Piotrowska, Teresa; Laursen, Mette K; Andersen, Jens S; Sørensen, Helle F; Klink, Rabih

    2018-02-01

    Allergy immunotherapy targets the immunological cause of allergic rhinoconjunctivitis and allergic asthma and has the potential to alter the natural course of allergic disease. The primary objective was to investigate the effect of the SQ grass sublingual immunotherapy tablet compared with placebo on the risk of developing asthma. A total of 812 children (5-12 years), with a clinically relevant history of grass pollen allergic rhinoconjunctivitis and no medical history or signs of asthma, were included in the randomized, double-blind, placebo-controlled trial, comprising 3 years of treatment and 2 years of follow-up. There was no difference in time to onset of asthma, defined by prespecified asthma criteria relying on documented reversible impairment of lung function (primary endpoint). Treatment with the SQ grass sublingual immunotherapy tablet significantly reduced the risk of experiencing asthma symptoms or using asthma medication at the end of trial (odds ratio = 0.66, P year posttreatment follow-up, and during the entire 5-year trial period. Also, grass allergic rhinoconjunctivitis symptoms were 22% to 30% reduced (P years). At the end of the trial, the use of allergic rhinoconjunctivitis pharmacotherapy was significantly less (27% relative difference to placebo, P < .001). Total IgE, grass pollen-specific IgE, and skin prick test reactivity to grass pollen were all reduced compared to placebo. Treatment with the SQ grass sublingual immunotherapy tablet reduced the risk of experiencing asthma symptoms and using asthma medication, and had a positive, long-term clinical effect on rhinoconjunctivitis symptoms and medication use but did not show an effect on the time to onset of asthma. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  4. A novel method to characterize silica bodies in grasses.

    Science.gov (United States)

    Dabney, Clemon; Ostergaard, Jason; Watkins, Eric; Chen, Changbin

    2016-01-01

    The deposition of silicon into epidermal cells of grass species is thought to be an important mechanism that plants use as a defense against pests and environmental stresses. There are a number of techniques available to study the size, density and distribution pattern of silica bodies in grass leaves. However, none of those techniques can provide a high-throughput analysis, especially for a great number of samples. We developed a method utilizing the autofluorescence of silica bodies to investigate their size and distribution, along with the number of carbon inclusions within the silica bodies of perennial grass species Koeleria macrantha. Fluorescence images were analyzed by image software Adobe Photoshop CS5 or ImageJ that remarkably facilitated the quantification of silica bodies in the dry ash. We observed three types of silica bodies or silica body related mineral structures. Silica bodies were detected on both abaxial and adaxial epidermis of K. macrantha leaves, although their sizes, density, and distribution patterns were different. No auto-fluorescence was detected from carbon inclusions. The combination of fluorescence microscopy and image processing software displayed efficient utilization in the identification and quantification of silica bodies in K. macrantha leaf tissues, which should applicable to biological, ecological and geological studies of grasses including forage, turf grasses and cereal crops.

  5. Ensilage of tropical grasses mixed with legumes and molasses.

    Science.gov (United States)

    Tjandraatmadja, M; Norton, B W; Mac Rae, I C

    1994-01-01

    The effects of adding two legumes, Gliricidia sepium and Leucaena leucocephala, cv. Cunningham, and molasses on the fermentation characteristics of silages made from two tropical grasses (Pangola grass, Digitaria decumbens, and Setaria sphacelata cv. Kazungula) were investigated. Pangola grass silages contained significantly higher contents of water-soluble carbohydrates and lactic acid than did setaria silages after 100 days fermentation, but there were no significant differences between the two silages in populations of lactic acid bacteria and contents of total N and NH3-N. Addition of either species of legume had no significant effect on fermentation acids and NH3-N contents, and numbers of lactic acid bacteria. Addition of both legumes reduced NH3-N production in the silages by 59% after 5 days' fermentation. Numbers of lactic acid bacteria were not significantly affected by the different treatments. Enterococcus faecalis represented 60% of the lactic acid bacteria isolated from the treated herbages prior to ensiling. By 100 days of fermentation, only lactobacilli were isolated: 82% homo-fermenters and 18% hetero-fermenters. Lactobacillus mesenteroides subsp. dextranicum was found only in the silage supplemented with 33% (w/w) legume. It was concluded that the low quality of tropical grasses used as feeds for ruminants may be significantly improved by ensiling these grasses with small amounts of molasses and with high-protein tree leaves.

  6. Grass meristems II: inflorescence architecture, flower development and meristem fate.

    Science.gov (United States)

    Tanaka, Wakana; Pautler, Michael; Jackson, David; Hirano, Hiro-Yuki

    2013-03-01

    Plant development depends on the activity of various types of meristems that generate organs such as leaves and floral organs throughout the life cycle. Grass species produce complex inflorescences and unique flowers. The grass inflorescence is composed of different types of branches, including a specialized branch called a spikelet. The spikelet is a special unit of the inflorescence and forms one to several florets, depending on the species. In the floret, floral organs such as perianth organs, carpels and stamens are formed. In Arabidopsis, because the inflorescence meristem (IM) forms the floral meristems (FMs) directly on its flanks, the change of meristem fate is relatively simple. In contrast, in grasses, different types of meristem, such as the IM, the branch meristem (BM), the spikelet pair meristem (SPM) in some grasses, the spikelet meristem (SM) and the FM, are responsible for the elaboration of their complex inflorescences and flowers. Therefore, sequential changes of meristem fate are required, and a number of genes involved in the specification of the fate of each meristem have been identified. In this review, we focus on the following issues concerning the fate of the reproductive meristems in two grass species, maize (Zea mays) and rice (Oryza sativa): (i) meristem regulation during inflorescence development; (ii) specification and fate change of the BM and the SM; (iii) determinacy of the FM; and (iv) communication between the meristem and lateral organs.

  7. Designing hybrid grass genomes to control runoff generation

    Science.gov (United States)

    MacLeod, C.; Binley, A.; Humphreys, M.; King, I. P.; O'Donovan, S.; Papadopoulos, A.; Turner, L. B.; Watts, C.; Whalley, W. R.; Haygarth, P.

    2010-12-01

    Sustainable management of water in landscapes requires balancing demands of agricultural production whilst moderating downstream effects like flooding. Pasture comprises 69% of global agricultural areas and is essential for producing food and fibre alongside environmental goods and services. Thus there is a need to breed forage grasses that deliver multiple benefits through increased levels of productivity whilst moderating fluxes of water. Here we show that a novel grass hybrid that combines the entire genomes of perennial ryegrass (Lolium perenne - the grass of choice for Europe’s forage agriculture) and meadow fescue (Festuca pratensis) has a significant role in flood prevention. Field plot experiments established differences in runoff generation with the hybrid cultivar reducing runoff by 50% compared to perennial ryegrass cultivar, and by 35% compared to a meadow fescue cultivar (34 events over two years, replicated randomized-block design, statistically significant differences). This important research outcome was the result of a project that combined plant genetics, soil physics and plot scale hydrology to identify novel grass genotypes that can reduce runoff from grassland systems. Through a coordinated series of experiments examining effects from the gene to plot scale, we have identified that the rapid growth and then turnover of roots in the L. perenne x F. pratensis hybrid is likely to be a key mechanism in reducing runoff generation. More broadly this is an exciting first step to realizing the potential to design grass genomes to achieve both food production, and to deliver flood control, a key ecosystem service.

  8. Effect of Removal of Woody Biomass after Clearcutting and Intercropping Switchgrass (Panicum virgatum with Loblolly Pine (Pinus taeda on Rodent Diversity and Populations

    Directory of Open Access Journals (Sweden)

    Matthew M. Marshall

    2012-01-01

    Full Text Available Plant-based feedstocks have long been considered viable, potential sources for biofuels. However, concerns regarding production effects may outweigh gains like carbon savings. Additional information is needed to understand environmental effects of growing feedstocks, including effects on wildlife communities and populations. We used a randomized and replicated experimental design to examine initial effects of biofuel feedstock treatment options, including removal of woody biomass after clearcutting and intercropping switchgrass (Panicum virgatum, on rodents to 2 years post-treatment in regenerating pine plantations in North Carolina, USA. Rodent community composition did not change with switchgrass production or residual biomass removal treatments. Further, residual biomass removal had no influence on rodent population abundances. However, Peromyscus leucopus was found in the greatest abundance and had the greatest survival in treatments without switchgrass. In contrast, abundance of invasive Mus musculus was greatest in switchgrass treatments. Other native species, such as Sigmodon hispidus, were not influenced by the presence of switchgrass. Our results suggest that planting of switchgrass, but not biomass removal, had species-specific effects on rodents at least 2 years post-planting in an intensively managed southern pine system. Determining ecological mechanisms underlying our observed species associations with switchgrass will be integral for understanding long-term sustainability of biofuels production in southern pine forest.

  9. Response surface studies that elucidate the role of infiltration conditions on Agrobacterium tumefaciens-mediated transient transgene expression in harvested switchgrass (Panicum virgatum)

    Energy Technology Data Exchange (ETDEWEB)

    VanderGheynst, J.S.; Guo, H.-Y.; Simmons, C.W. [Department of Biological and Agricultural Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616 (United States)

    2008-04-15

    Agrobacterium tumefaciens-mediated transient expression (agroinfiltration) experiments were performed in harvested switchgrass (Panicum virgatum) leaves to identify the effects of wounding by bead beating, surfactant concentration and vacuum application on in planta {beta}-glucuronidase expression and leaf decay. Expression was scored based on a consistent pattern of visual observations of histochemical staining over the leaf surface as might be observed in stable gene expression in switchgrass leaves. Assays on extracts from leaves were also performed to measure expression levels; however, these assays showed low expression levels, which may have been due to low recombinant protein recovery and decomposition in the leaf. Bead beating was successful for wounding the plant surface, but did not improve the consistency of expression based on histochemical staining observations. Surfactant was necessary for improving contact between the leaf surface and Agrobacterium suspension and consistently improved expression when vacuum application level was low (25 kPa). Increasing vacuum application from 25 to 5 kPa improved expression only when surfactant concentration was low. When a suspension of A. tumefaciens containing 1000 ppm Break-Thru surfactant was added to harvested leaves and 25 kPa vacuum applied, a fairly uniform expression was visualized across the leaf surface within 2-3 days of incubation, suggesting that agroinfiltration is a rapid tool for examining expression of transgenes in switchgrass leaves. (author)

  10. Distribution models for Panicum virgatum (Poaceae) reveal an expanded range in present and future climate regimes in the northeastern United States.

    Science.gov (United States)

    Ahrens, Collin W; Meyer, Thomas H; Auer, Carol A

    2014-11-01

    Expanded area cultivated with the bioenergy crop Panicum virgatum (switchgrass) could alter the genetics of native populations through gene flow, so understanding current and future species distribution is a first step toward estimating ecological impacts. We surveyed switchgrass distribution in the northeastern United States and generated statistical models to address hypotheses about current distribution relative to historical records and responses to climate change. Surveys were conducted on 1600 km of road verges along environmental gradients. Switchgrass abundance became the training data for two multivariate generalized linear models that generated maps representing the probability of switchgrass in road verges. Models were evaluated and the superior model was used with variables from three climate change scenarios for 2050 and 2099. Switchgrass populations were found in 41% of roadside plots and up to 188 km from the coast. The environmental variables temperature, urban areas, and sandy soils were positively correlated with switchgrass presence, while elevation, soil pH, and distance to the coast were negatively correlated. The model without spatial autocorrelation performed better. Models and maps incorporating climate change predictions showed a sharp northward shift in suitable habitat. Switchgrass populations in the northeastern United States occur on inland road verges, supporting the idea that species distribution has expanded relative to historical descriptions of a restricted coastal habitat. The optimal model showed that mean temperature, elevation, and urban development were important in switchgrass distribution today, and climate change will increase suitable habitat for future bioenergy production and wild populations. © 2014 Botanical Society of America, Inc.

  11. Comparison of two organic fertilizers along with Zn and B elements on concentration, uptake of nutrients and some growth parameters in millet (Panicum miliaceum L.

    Directory of Open Access Journals (Sweden)

    T Nezhad hoseini

    2016-05-01

    Full Text Available A field experiment was conducted to study the effect of two organic fertilizers along with zinc and boron elements on some growth parameters, concentration and uptake of nutrients in millet (Panicum miliaceum L. by using factorial based on randomized completely block design with three replications in Qaen region, Iran. The main treatments were municipal solid waste compost and cow manure (each at 0 and 25 t.ha-1 and sub treatments were elements of Zn (0, 50 kg.ha-1 and B (0, 10 kg.ha-1 using their respective ZnSO4 and H3BO3 salts. Results showed that treatments interaction had significant effects on total dry matter yield, number of tillers per plant and plant height of Millet. The highest total dry matter production was achieved by interaction of cow manure along with Zn and B elements. Concentrations of N, Fe, Zn, B and Cu in plant were increased significantly by treatments interaction effects compared to control. Interaction effect of organic fertilizers with B (in the absence of Zn enhanced plant B concentration significantly, whereas, interaction of organic fertilizers with Zn (in the absence of B decreased B concentration in plant. The highest plant uptake of N, P, K, Zn, and B was observed in plots with cow manure and Zn and B elements.

  12. Productivity and nutritional quality of Flechinha grass ( Echinolaena inflexa , native grass of Brazilian Cerrado

    Directory of Open Access Journals (Sweden)

    Sylvia Rocha e Silveira

    2016-06-01

    Full Text Available ABSTRACT: Due to scarce nutritional data, this study assessed the productivity and nutritional value of Echinolaena inflexa (EI grass, native to the Cerrado biome. It was compared to B. brizantha (BB, one of the most cultivated grasses in Brazil, during a whole year (rainy; RS and dry season; DS. Sampling was held in accordance with pasture management (entry / exit height; 50 / 5cm and 80 / 25cm for EI and BB, respectively. Dry matter production (DMP, crude protein (CP, neutral and acid detergent fiber (NDF; ADF, hemicellulose (HCEL, PB insoluble neutral and acid detergent (PIDN; PIDA, total and non-fibrous carbohydrates (TC; NFC, ether extract (EE, and mineral matter (MM, and in vitro fermentation kinetics and DM degradability (DMD were evaluated. A completely randomized design (season as a fixed term and average treatment compared by Tukey post test were applied. EI produced 38.5% of the DMP of BB. A higher CP (75.3; 73.5 in the RS and DS, PIDA (12.5; 8.7, PIDN (47.1; 40.1, NDF (714.4; 749.5 and ADF (396.0; 419.0 were obtained by EI in relation to BB (CP (60.3; 33.5, PIDA (6.0; 3.5, PIDN (21.4; 10.8, NDF (673.0; 675.1 and ADF (335.5; 351.4 during the RS and DS, respectively (g kg-1 DM. In vitro data were directly associated with chemical composition, resulting in lower DMD of EI compared to BB. EI showed productive similarity (DMP during RS and DS (939.3; 809.8kg DM respectively. Although EI showed greater nutritional stability (CP between seasons, 17% of CP was linked to ADF and therefore, not available for rumen microorganisms.

  13. Two-dimensional maximum entropy image restoration

    International Nuclear Information System (INIS)

    Brolley, J.E.; Lazarus, R.B.; Suydam, B.R.; Trussell, H.J.

    1977-07-01

    An optical check problem was constructed to test P LOG P maximum entropy restoration of an extremely distorted image. Useful recovery of the original image was obtained. Comparison with maximum a posteriori restoration is made. 7 figures

  14. Ensiling as pretreatment of grass for lignocellulosic biomass conversion

    DEFF Research Database (Denmark)

    Ambye-Jensen, Morten

    an efficient production of ethanol. Lastly, the conversion of xylan was extremely low in both grass and grass silage. Optimization of the enzymatic saccharification of grass was attempted through improvement of the hemicellulase content in the enzyme blend. However, neither additional xylanases (Cellic HTec2......Development of sound technologies of biomass conversion will be increasingly important for many years to come as planetary bounderies drive the development towards a biobased society. Pretreatment of lignocellulosic biomass is, in this regard, an essential technology. Current pretreatment methods...... method with low cost and low energy requirements, plus brings about multiple advantages with regards to agricultural management. However, the pretreatment effect of ensiling, and the overall effects for further conversion are limited. In this study, ensiling was evaluated as a method of pretreatment...

  15. Lemon grass oil for improvement of oral health

    Directory of Open Access Journals (Sweden)

    Ruckmani Rajesvari

    2013-01-01

    Full Text Available Lemon grass essential oil has been used for decades to treat respiratory infections, sinusitis, bladder infections, high cholesterol, digestive problem, varicose veins and also for regeneration of connective tissue. It has anti spasmodic, anti-pyretic, anti-fungal, anti-bacterial, anti-inflammatory, anti-septic, insect repellent, sedative, vasodilator and flavoring properties. In china, it has been used traditionally as a remedy for stomach and liver diseases and also to treat rheumatism. Since lemon grass oil possess various pharmacological actions, it is also quite useful in dentistry. Hence, the objective of this article is to highlight various uses of lemon grass oil in the dental field and in the medical field in order to aid the professionals for future research.

  16. Variations of Roughness Coefficients with Flow Depth of Grassed Swale

    Science.gov (United States)

    Mustaffa, N.; Ahmad, N. A.; Razi, M. A. M.

    2016-07-01

    Grassed swales are the best management practice (BMP), which has been widely used to reduce the peak flow, reduce water pollution through vegetated filtration, and improve the groundwater recharge. Universiti Tun Hussein Onn Malaysia (UTHM) is using the approach of grassed swales recommended by the Department of Irrigation and Drainage Malaysia (DID) for reducing the risk of flooding and controlling the water pollution. This paper investigates the variations of roughness coefficients with the flow depth of grassed swales in the campus of UTHM. Fieldwork was carried out on the grassed swale to collect the hydraulic data, which including the levelling work, measuring the flow depth and flow velocity of the swale. The flow depth of swale was taken at three points divided along the width of swale and the flow velocity is captured three times at each of the point. The variations of roughness coefficients of grassed swales are presented in Manning's equation, and the results reveal that the n value increases with the increasing of flow depth. Manning's coefficient value found in this study is in the range of 0.110 to 0.756, which are higher than the value proposed by the Urban Stormwater Management Manual for Malaysia (MSMA). The relationships of flow depth and velocity at each section of the swale are portrayed in graphs, which show that the velocity increases with the decreasing of flow depth. The outcomes of this study can be concluded that the variation of Manning's coefficient value is influenced by the swale profile, flow depth, flow velocity, and as well as the vegetation used in the grassed swale concerned.

  17. Production of ethanol from hemicellulose fraction of cocksfoot grass using pichia stipitis

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Iversen, Jens Asmus; Uellendahl, Hinrich

    2013-01-01

    Background: In this study, cocksfoot grass (Dactylis glomerata), an abundant lignocellulosic biomass was pretreated using different operational parameters using wet explosion (WEx) pretreatment for accessing the bioethanol potential of the hemicellulose fraction. Utilization of the hemicellulose...... conditions was in the range of 89 to 158 mL/kg DM, with the highest yield (92% of theoretical maximum value) found for the lower pretreatment severity at 160°C, 15 min, 87 psi oxygen. Conclusions: Our findings from this present study demonstrated that the release of hemicellulose sugars in the liquid...... hydrolysate is maximal when a lower pretreatment severity is applied. This is evident as the highest ethanol yields were found under the pretreatment conditions at lower severity....

  18. Growth and use of energy grasses as a fuel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-09-01

    This summary outlines the main conclusions of the project which aims to provide information on the growth, yields, and combustion characteristics of Miscanthus, switchgrass, Spartina, rye, and reed canary grass. Details are given of the small-plot trials of the non-wood biomass fuels, the planting, pests and diseases, the falling over of crops, the time of harvest, moisture content, yields, combustion trials, fuel and ash characterisation, and costs/income. Tables are provided illustrating the cumulative yield, the costs of the different species of energy grasses, and the annual mean gross margins over 5, 10, 15, and 20 years.

  19. Determination of 90Sr in grass and soil

    International Nuclear Information System (INIS)

    Bajo, S.; Keil, R.

    1994-10-01

    A radiochemical method for the determination of 90 Sr in non-contaminated grass and soil is presented. The method is based on the leaching of 90 Sr from the mineralized samples followed by liquid-liquid extraction of 90 Y, its short lived daughter, by tributylphosphate and precipitation of Y-oxalate, which is counted in a low-level proportional counter. Based on dried samples of 30 g of soil and 100 g of grass the limit of detection is about 0.1 Bq/kg for both materials. (author) figs., tabs., 43 refs

  20. Results from the 5-year SQ grass sublingual immunotherapy tablet asthma prevention (GAP) trial in children with grass pollen allergy

    DEFF Research Database (Denmark)

    Valovirta, Erkka; Petersen, Thomas H; Piotrowska, Teresa

    2018-01-01

    compared with placebo on the risk of developing asthma. METHODS: A total of 812 children (5-12 years), with a clinically relevant history of grass pollen allergic rhinoconjunctivitis and no medical history or signs of asthma, were included in the randomized, double-blind, placebo-controlled trial......, comprising 3 years of treatment and 2 years of follow-up. RESULTS: There was no difference in time to onset of asthma, defined by prespecified asthma criteria relying on documented reversible impairment of lung function (primary endpoint). Treatment with the SQ grass sublingual immunotherapy tablet...... significantly reduced the risk of experiencing asthma symptoms or using asthma medication at the end of trial (odds ratio = 0.66, P year posttreatment follow-up, and during the entire 5-year trial period. Also, grass allergic rhinoconjunctivitis symptoms were 22% to 30% reduced (P

  1. Maximum Power from a Solar Panel

    Directory of Open Access Journals (Sweden)

    Michael Miller

    2010-01-01

    Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

  2. Hyperspectral remote sensing techniques for grass nutrient estimations in savannah ecosystems

    CSIR Research Space (South Africa)

    Ramoelo, Abel

    2010-03-01

    Full Text Available at various scales such as local, regional and global scale. Traditional field techniques to measure grass nutrient concentration have been reported to be laborious and time consuming. Remote sensing techniques provide opportunity to map grass nutrient...

  3. Development of Alternative Overtopping-Resistant Sea Defences, Phase 2 : Elaboration of Smart Grass Reinforcement Concept

    NARCIS (Netherlands)

    Verhagen, H.J.; Van Gerven, K.A.J.; Van der Meer, J.W.; Van Heereveld, M.A.; Akkerman, G.J.

    2005-01-01

    In the present report, a Smart Grass Reinforcement for overtopping resistant sea defences is elaborated on a theoretical basis, within the framework of ComCoast, Work Package 3 (WP3). The smart grass revetment concept aims at strengthening the present grass revetments at the crests and inners slopes

  4. Tensile fracture properties of seven tropical grasses at different phenological stages

    NARCIS (Netherlands)

    Jacobs, A.A.A.; Scheper, J.A.; Benvenutti, M.A.; Gordon, I.J.; Poppi, D.P.; Elgersma, A.

    2011-01-01

    The intake of forage grasses by grazing ruminants is closely related to the mechanical fracture properties of grasses. The relationship between the tensile fracture properties of grasses and foraging behaviour is of particular importance in tropical reproductive swards composed of both stems and

  5. Role of ammonia and biogenic amines in intake of grass silage by ruminants

    NARCIS (Netherlands)

    Os, van M.

    1997-01-01

    In Northern- and Western-Europe, grass silage is a major component in winter feeding rations for ruminants. The intake of ensiled grass is often lower than the intake of hay or the fresh grass of similar digestibility. This intake depression is attributed to the fermentation products

  6. Effect of fire intensity on the grass and bush components of the ...

    African Journals Online (AJOL)

    The results provide valuable guidelines for the use of fire in controlling bush encroachment. Keywords: Bush; Bush encroachment; Eastern Cape; effect of fire; Fire; Fire intensity; fire regime; Grass; grass sward; grasses; recovery; Savanna; south africa; Thornveld; Vegetation recovery; Veld burning. Journal of the Grassland ...

  7. A review on foggage in the central grass veld with special reference ...

    African Journals Online (AJOL)

    It is clear from these results that Smuts finger grass can play an important role during the winter period as animal feed. Keywords: afrikaans; animal production; digitaria eriantha; foggage; grasses; grazing capacity; literature review; management; semi-arid regions; smuts fingergrass; tropical grass; western transvaal ...

  8. Impact on Clover-Grass Yield from Wheel Load and Tyre Pressure

    DEFF Research Database (Denmark)

    Green, Ole; Jørgensen, Rasmus Nyholm; Sørensen, Claus Aage Grøn

    2009-01-01

    Traffic intensities have been shown to have a negative influence on the yield of grass and clover. A full scale grass-clover field trial was established to estimate the effect on clover-grass yields as a function of different wheel loads and tire pressures. The trial comprised 16 different traffi...

  9. Reduction in clover-grass yield caused by different traffic intensities

    DEFF Research Database (Denmark)

    Green, Ole; Jørgensen, Rasmus Nyholm; Kristensen, Kristian

    Different traffic intensities have been shown to have a negative influence on the yield of grass and clover. A full scale grass-clover field trial was established to estimate the effect on clover-grass yields as a function of different wheel loads and tire pressures. The trial comprised 16 differ...

  10. Genetic variability and relationship between MT-1 elephant grass ...

    Indian Academy of Sciences (India)

    College of Agriculture, South China Agricultural University, Guangzhou 510642, People's Republic of China. Abstract. Genetic variability and relationships among elephant grass cultivars were estimated by the SRAP (sequence-related amplified polymorphism) assay. A total of 60 individuals collected from five cultivars in ...

  11. Identification of Radical Scavengers in Sweet Grass (Hierochloe odorata)

    NARCIS (Netherlands)

    Pukalskas, A.; Beek, van T.A.; Venskutonis, R.P.; Linssen, J.P.H.; Veldhuizen, van A.; Groot, de Æ.

    2002-01-01

    Extracts from aerial parts of sweet grass (Hierochloe odorata) were active DPPH free radical scavengers, The active compounds were detected in extract fractions using HPLC with on-line radical scavenging detection. After multistep fractionation of the extract, two new natural products possessing

  12. The potential of C4 grasses for cellulosic biofuel production

    NARCIS (Netherlands)

    Weijde, van der R.T.; Alvim Kamei, C.L.; Torres Salvador, A.F.; Vermerris, W.; Dolstra, O.; Visser, R.G.F.; Trindade, L.M.

    2013-01-01

    With the advent of biorefinery technologies enabling plant biomass to be processed into biofuel, many researchers set out to study and improve candidate biomass crops. Many of these candidates are C4 grasses, characterized by a high productivity and resource use efficiency. In this review the

  13. INTAKE AND DIGESTIBILITY OF LOW QUALITY RHODES GRASS ...

    African Journals Online (AJOL)

    An experiment was conducted at Bunda College, Malawi, to determine the effect of magadi (a sodium sesquicarbonate- Na2CO3, NaHCO3.2H2O) treated forages on their intake and digestibility and growth of sheep. Rhodes grass (Chloris gayana Kunth), Cedrela (Toona ciliata, M. Roem) and Sesbania [Sesbania sesban ...

  14. International Education in Japan: Response of the Grass-Eaters

    Science.gov (United States)

    Carpenter, Walter

    2012-01-01

    This paper reviews some of the reasons why a majority of Japanese university students are not interested in study-abroad, international-education type programs. A general consensus in Japan is that disinterest in studying abroad is reflective of the values held by many Japanese young people, often referred to as the "grass-eating"…

  15. Grass species selection patterns on rotationally-grazed Dohne ...

    African Journals Online (AJOL)

    Herbaceous species preference was studied during autumn and winter periods of occupation, on rotationally-grazed Dohne Sourveld, at four different stocking rates. Reports on species selection by cattle and sheep grazing together. Illustrates with graphsLanguage: English. Keywords: Grass species; Herbage availibility; ...

  16. Carcass mass gains of steers grazing star grass, with different ...

    African Journals Online (AJOL)

    Carcass mass gains of steers grazing dryland Cynodon aethiopicus cv. No. 2 Star grass pastures during the growing season were determined for each of 16 treatments comprising four levels of nitrogen fertilisation in combination with four overlapping sets of stocking rates. The treatments were repeated over four growing ...

  17. Environmental control of flowering in tropical - subtropical grasses ...

    African Journals Online (AJOL)

    Tropical-subtropical grasses have shown a wide range of response to photoperiod. Some of the response patterns which they exhibit are extremely complex and often seem unrelated to the conditions to which the plants are adapted. However, there is an increasing realisation of the possible role of factors of the ...

  18. Short Communication: Habitat preferences of twenty-three grass ...

    African Journals Online (AJOL)

    Some grass species occur more frequently in certain habitats than in others, but uncertainty as to exactly which factors are responsible for this phenomenon exist. Species composition as well as habitat data were collected from plots situated on the mild slopes of the study area, and the data were analysed by means of a ...

  19. A new grass frog from Namibia | Channing | African Zoology

    African Journals Online (AJOL)

    A new species of grass frog of lhe genus Ptychadena is described from northern Namibia. Although superficially similar to Ptychadena schillukorum and Ptychadena mossambica, the new species differs In advertisement call, and external characters. An examination of a series of published sonagrams indicates that ...

  20. Grass-roots approach: developing qualified nuclear personnel

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    Nuclear power plants experiencing personnel recruitment problems are trying a grass-roots approach to increase the manpower pool. The Philadelphia Electric Co. and the Toledo Edison Co. are working with local educational institutions to offer nuclear-technology training specific to the needs of nuclear plants. The utilities' investment covers much of the cost of instruction as well as continued training for employees