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The present study described the chemical composition and somatic cell score (SCS) of samples of refrigerated raw milk collected from commercial farms in the state of Rio Grande do Sul in order to better understand the behavior of constituents present in non-fatty solids (NFS) in milk according to the season of the year. Means were used to describe statistical data. To estimate the probability of NFS levels meeting IN 76 (BRAZIL, 2018), binary logistic regression was used. It was reported that 18.2% (233.817) of analytical results showed NFS below 8.4%, representing the minimum required by IN 76. The highest average NFS level observed in the five-year period was registered in the micro-region of Passo Fundo (8.70%) in winter. The microregion with the lowest results was Porto Alegre (8.53%); however, it still demonstrated levels within the limits established by IN 76. The study indicates that milk constituents show differences between seasons. In autumn and winter, the constituents remained equal to or higher than those required by current legislation, while spring and summer were the periods with the lowest NFS values. The SCS was also influenced by the seasons, with the highest rates in spring, summer, and autumn. RESUMO: O presente estudo teve como objetivo descrever os resultados de composição química e escore de células somáticas (ECS) de amostras de leite cru refrigerado coletado em fazendas comerciais no estado do Rio Grande do Sul, para melhor entendimento do comportamento dos constituintes presentes nos sólidos não gordurosos (SNG) no leite de acordo com as estações do ano. As médias foram estudadas para descrever as estatísticas dos dados. Para estimar a probabilidade de os teores de SNG atenderem à IN 76 de 2018, foi utilizada a regressão logística binária. Foi constatado que 18,2% (233.817) dos resultados analíticos apresentaram SNG abaixo de 8,4%, que representa o mínimo exigido pela IN 76 (BRASIL, 2018). A maior média de SNG observada no período de cinco anos foi registrada na microrregião de Passo Fundo (8,70%), no inverno. A microrregião com menores resultados foi a de Porto Alegre (8,53%), no entanto com teores dentro do estabelecido pela IN 76/2018. O estudo demonstrou que os constituintes do leite apresentaram diferenças entre as estações do ano. O outono e inverno foram os períodos em que os constituintes se mantiveram iguais ou superiores aos exigidos pela legislação vigente, enquanto que a primavera e o verão foram os períodos com os menores valores de SNG. O ECS também foi influenciado pelas estações do ano. Na primavera, verão e outono ocorreram os maiores índices.

The runout of newly cultivated areas in the world without recurring to the deforestation, demand a necessity to improve yield to sustain a growth population which demands each time more food. To avoid that is necessary to solve the main issues which cause crop productivity reduction, such as lodging which causes yield reduction in many major crops such as wheat, barley, rice and oat. In this sense, a study with eight cultivars evaluated morphological traits of the stem as crown diameter, internal and external diameter of the first four basal internodes, the length of internodes, peduncle and panicle, plant height, and also lodging resistance factor (cLr), green and dry panicle matter. The diameter of the crown does not show differences among the cultivars, the morphological characters which showed correlation and relative contribution with cLr were the internal and external internodes diameters, showing their capacity to be one of morphological traits of the stem to an indirect selection of resistance to lodging in Avena sativa L. The length did not show a good correlation with lodging, probably due to the fact that this trait was the focus of breeders for many years, reaching the plateau, demanding focus in other traits to avoid lodging such as interna and external diameter of internodes. The cultivar URS Brava and IPR Afrodite demonstrated to be a source of lodging resistance in oat.

The objective of this study was to evaluate the resistance reaction of Avena spp. after inoculation of different concentrations of eggs and juveniles of M. javanica and M. incognita. Ten oat genotypes (Avena sativa: UPFPS Farroupilha, UPFA Ouro, IPR Afrodite, AF1345 Ucraniana; A. strigosa: Agro Quaraí, Agro Esteio, Embrapa 139, Iapar 61 Ibiporã, UPFA 21 Moreninha, AF 12202) were evaluated in bioassays for resistance against the root-knot nematodes, Meloidogyne javanica and M. incognita. Susceptible (Solanum lycopersicum and Glycine max) and resistant (Crotalaria spectabilis) species were used as control treatments. Depending on the inoculum level, the oats showed a different response to nematodes. All genotypes of oats were resistant to M. javanica when a high inoculum level (5,000 eggs and J2 per plant) was used but under low inoculum level (1,500 eggs and J2 per plant), AF 12202, Iapar 61 Ibiporã, Agro Esteio and Agro Quaraí were susceptible. All genotypes of oats were resistant to the inoculation of 2,900 eggs and J2 of M. incognita, except for ‘Iapar 61’ that showed susceptibility in this concentration. At lower inoculum level (1,500 eggs and J2) Agro Quaraí, Agro Esteio and Iapar 61 Ibiporã were susceptible. The reaction of oats to M. javanica and M. incognita depends on the inoculum level. The resistance reaction at low inoculum density of A. sativa ‘AF 1345 Ucraniana’ and ‘IPR Afrodite’ allows its use in breeding programs in oats and suggests the possibility of management tool in areas infested with both root-knot nematode species.

The structure of arbuscular mycorrhizal fungi (AMF) communities in areas under strawberry cultivation in the Brazilian subtropics has been poorly studied. Thus, we characterized cultivated and native forest soils, of reference-sites in strawberry cultivation in southern Brazil, regarding the AMF community and investigate if there is variability in the diversity in the mycorrhizal communities of these soils. For this, we evaluated eight soils, in a completely randomized design experiment. We observed that the species Claroideoglomus aff. luteum, Claroideoglomus claroideum, C. etunicatum, Funneliformis mosseae and Glomus sp2 were the most frequent. Native forest soils had more fungal species than cultivated soils. Soils little anthropized under strawberry cultivation resembled the natural soils regarding the AMF heterogeneity. We conclude that there are AMF diversity in soils of reference-sites in strawberry cultivation, and that C. claroideum and C. etunicatum are generalist, independent of the ecosystem. This study contributes significantly to our knowledge about the community composition of AMF in soils of reference-sites in the strawberry cultivation in the Brazilian subtropics. Thus, it becomes possible the development of inoculants for this horticultural crop, with the role of making their cultivation more sustainable.

In view of the rapid evolution of Conyza sumatrensis populations resistant to glyphosate, it is necessary to understand the genetic diversity aimed to improve strategies for managing this weed. We investigated the genetic dissimilarity among 15 biotypes of C. sumatrensis from different geographic regions using microsatellite loci. The biotypes, were cultivated in a greenhouse to obtain vegetal material for DNA extraction. Nineteen microsatellite markers (SSR), were developed for C. sumatrensis biotypes. The genetic dissimilarity was estimated by the Jaccard coefficient (JC) and the biotypes grouped by the UPGMA method. The results demonstrated a high dissimilarity (JC = 7.14 to 82.62) of the analyzed material, with the biotypes forming five groups, being one group formed just by the susceptible biotype and in the others grouped by biotypes from distinct locations in the same group The high genetic diversity of C. sumatrensis indicates that the biotypes may show different responses to different management strategies, and that the mechanisms of resistance to herbicides and characteristics of evolution of populations due to adaptability may be some of the factors involved in the genetic variability of the species. Keywords: polymorphism; SSR; tall fleabane; genetic variability RESUMO: Tendo em vista a rápida evolução das populações de Conyza sumatrensis resistentes ao glifosato, é necessário entender a diversidade genética com vistas a melhorar as estratégias de manejo dessa planta daninha. Diante do exposto, objetivou-se com este trabalho investigar a dissimilaridade genética entre 15 biótipos de C. sumatrensis de diferentes regiões geográficas usando marcadores moleculares microssatélites. Os biótipos foram cultivados em casa de vegetação, para obtenção de material vegetal para extração de DNA. Dezenove marcadores microssatélites (SSR) foram desenvolvidos para os biótipos de C. sumatrensis. A dissimilaridade genética foi estimada pelo coeficiente de Jaccard (JC), e os biótipos, agrupados pelo método UPGMA. Os resultados demonstraram alta dissimilaridade (JC = 7,14 a 82,62) do material analisado, com os biótipos formando cinco grupos. A alta diversidade genética de C. sumatrensis indica que os biótipos podem apresentar distintas respostas a diferentes estratégias de manejo e que os mecanismos de resistência a herbicidas podem ser um dos fatores envolvidos na variabilidade genética das espécies. Palavras-chave: polimorfismo; SSR; buva; variabilidade genética Made available in DSpace on 2021-02-26T12:01:57Z (GMT). No. of bitstreams: 1 0100-8358-PD-38-e020220570.pdf: 449804 bytes, checksum: e87c3ca03e0448545e514f0a87804810 (MD5) Previous issue date: 2020

This study investigated the residual effects of pig slurry (PS) applied to common carpet grass pasture (Axonopus affinis) for two years (September 2008-March 2010) on dry matter yield and forage-nitrogen uptake from October 2010-May 2011. A field experiment was conducted in a randomized complete block design with four replications. The treatments were 102, 204, 306, 408, and 510 m3 ha-1 pig slurry applied for two years; one mineral nitrogen rate (1,250 kg ha-1 ammonium nitrate) for two years; and no nitrogen fertilization (control). The pasture was cut at intervals of 48, 34, 43 and 69 days, which corresponded to 266, 300, 343, and 412 days after the last fertilizer application, respectively. Dry matter yield increased by 398 kg ha-1 for each 100 m3 of PS applied, the equivalent of 317 and 564 kg ha-1 for each 100 kg ha-1 of inorganic and organic N applied, respectively. The residual effect of PS on dry matter yield and forage-nitrogen uptake ranged from 11-45% and 8-40%, respectively, indicating a gradual release and availability of N in PS, which can help reduce the amounts of nitrogen applied to pasture.

Eragrostis plana (Nees) is an allelopathic plant with invasive potential in South American pastures. To isolate and identify phytotoxic compounds from leaves and roots of E. plana, a bioassay-directed isolation of the bioactive constituents was performed. This is the first report on a new diterpene carbon skeleton, neocassane, and of three new neocassane diterpenes, neocassa-1,12(13),15-triene-3,14-dione, 1; 19-norneocassa-1,12(13),15-triene-3,14-dione, 2; and 14-hydroxyneocassa-1,12(17),15-triene-3-one, 3, identified from the roots. Compounds 1, 2, and 3 inhibited the growth of duckweed by 50% at concentrations of 109 ± 28, 200 ± 37, and 59 ± 15 μM, respectively. Compound 2 was fungicidal to Colletotrichum fragariae, Colletotrichum acutatum, and Colletotrichum gloeosporioides. The compounds identified here could explain the allelopathy of E. plana. The description of the newly discovered compounds, besides contributing to the chemical characterization of the species, may be the first step in the study of the potential of these compounds as bioherbicides.

Eragrostis plana Nees (Poaceae), known commonly as tough lovegrass, is the most abundant invasive plant found in the rangelands of Southern Brazil. This study is the first to document the anatomical and histochemical features of the leaves and roots of this grass. Five leaf blades and five roots were collected, fixed in formaldehyde, glacial acetic acid, ethanol 70° (FAA 70), sectioned, stained, and photographed under a light microscope. Anatomical analysis of the leaves was supplemented with observations under a scanning electron microscope. Manual cuts were made into fresh material, which was subjected to specific reagents to determine the lipid, phenol, tannin, lignin, alkaloid, and starch presence. The analyses revealed that the leaves are amphistomatic with paracytic stomata, and the epidermis has lignified cells, a Kranz structure, collateral vascular bundles of two sizes, tectors, unicellular and crystalline trichomes. The roots are polyarc with air gaps on the cortical parenchyma, U-thickened endodermal cell walls and a parenchymatic pith with starch storage cells. Leaves and roots contain lipids, phenols, lignins, and alkaloids; starch is only present in the roots. Anatomical and histochemical traits of tough lovegrass suggest that the plant has adapted to survive under biotic and abiotic stress, which enhances its performance in relation to native plants. Key words: Anatomy, histochemistry, invasive.

This study was conducted in order to verify if the phenological stage and the nitrogen fertilization interfere in the allelopathic activity and in the concentration of potentially allelopathic phenolic compounds of tough lovegrass (Eragrostis plana). The assay consisted of a bifactor 3 (0.100 and 200 kg N ha-1) x 2 (harvested in vegetative and reproductive stages), in a split plot design. The N doses constituted the main plot and the phenological stage during the harvest the subplots, resulting in six treatments. The tough lovegrass plants derived from each of the treatments were subjected to allelopathy bioassays, in which aqueous extracts of the aerial parts were applied to lettuce cypselae (Lactuca sativa) and to phytochemicals tests when ethanolic extracts were used, with subsequent partition with ethyl acetate, followed by a high-performance liquid chromatography analysis. There was nitrogen x phenological stage interaction on biological and chemical attributes. The allelopathic extracts were, in descending order of inhibition of germination, those from plants harvested at the vegetative stage and fertilized with 100 kg N and at the flowering stage with 200 kg N, which showed the highest catechin concentrations. The caffeic, ferulic, p-coumaric and vanillic acids were in a higher concentration in flowered and fertilized plants with 0 or 200 kg N. The management of the nitrogen fertilization and the harvesting age influence the allelopathic activity and the phytochemical composition of tough lovegrass. RESUMO Este estudo foi realizado com o objetivo de verificar se a fenologia e a adubação nitrogenada interferem na atividade alelopática e na composição fenólica do capim-annoni (Eragrostis plana). O ensaio constou de um bifatorial 3 (0, 100 e 200 kg N ha-1) x 2 (colheita nos estádios vegetativo e reprodutivo), em arranjo de parcela subdividida. As doses de N constituíram a parcela principal, e o estádio fenológico por ocasião da colheita das plantas, as subparcelas, resultando em seis tratamentos. As plantas de capim-annoni, oriundas de cada um dos tratamentos, foram submetidas a bioensaios de alelopatia, em que extratos aquosos da parte aérea foram aplicados sobre cipselas de alface (Lactuca sativa); e a testes fitoquímicos, quando se utilizaram extratos etanólicos, com posterior partição com acetato de etila, seguido de análise por cromatografia líquida de alta eficiência. Houve interação nitrogênio x estádio fenológico sobre a alelopatia e a composição química do capim-annoni. Os extratos com maior potencial alelopático foram, em ordem decrescente de inibição na germinação, aqueles oriundos de plantas colhidas no estádio vegetativo e adubadas com 100 kg N e no estádio de florescimento com 200 kg N, que mostraram as maiores concentrações de catequina. Os ácidos cafeico, ferúlico, vanílico e p-cumárico estiveram em maior concentração nas plantas florescidas e adubadas com 0 ou 200 kg N. O manejo da adubação nitrogenada e a fenologia influenciam a atividade alelopática e a composição fenólica do capim-annoni.

This study aimed at verifying whether juvenile plants of alfalfa cultivars with different aptitude (grazingtype: Alfagraze and ABT 805; hay-type: Crioula) show morphophysiological differences in order to develop a protocol for early selection for grazing persistence. Two experiments were conducted in a greenhouse, in completely randomized design and three repeplicates. In Experiment 1, plants were evaluated from successive destructive harvests at 60, 90, 120 and 150 days of age. In Experiment 2, plants at 150 days of age were cut to a 10-cm stubble and harvested at 15 and 30 days of regrowth. In Experiment 1, Alfagraze showed the lowest height (19 cm), internode length (1.4 cm) and apical bud accessibility (15.3 cm). Grazing-type cultivars did not differ significantly for subterranean hypocotyl diameter (3.5 mm) on the mean ages, and at 120 days of age they had lower number of leaves (56/plant) and axillary stem (2.5/plant) number as well as aerial dry matter accumulation (DM = 0.99 g/plant) in comparison to Crioula. At 150 days of age, Alfagraze had the lowest aerial dry matter accumulation (0.86 g/plant) compared to the other cultivars (1.8 g/plant). In Experiment 2, Alfagraze had higher leaf number (172/plant) compared to the mean of ABT 805 and Crioula (114/plant). The characters with the highest relative contribution for genetic divergence were number of leaves at 120 days of age (Experiment 1) and at 15 and 30 days of regrowth (Experiment 2) totalizing 71.5%. The highest average Euclidean distance (d = 12.3) was from Alfagraze to Crioula and the smallest from ABT 805 to Crioula (d = 8.92). At the juvenile stage, it is possible to identify some grazing avoidance mechanisms in alfafa, such as the small plant height, lower apical bud accessibility and short internodes, as well as one of the grazing tolerance mechanisms, which is the increase in the number of leaves after cutting. For these characters, early selection is possible and Alfagraze can be used as witness. Este estudo objetivou verificar se plantas jovens de cultivares de alfafa de distinta aptidão (tipo-pastejo: Alfagraze e ABT 805; tipo-feno: Crioula) evidenciam diferenças morfofisiológicas, a fim de desenvolver um protocolo de seleção precoce para persistência ao pastejo. Dois ensaios foram conduzidos em casa-de-vegetação, com delineamento completamente casualizado e três repetições. No Experimento 1 as plantas foram avaliadas a partir de colheitas sucessivas e destrutivas aos 60, 90, 120 e 150 dias de idade. No Experimento 2, plantas com 150 dias foram cortadas a 10 cm da base e avaliadas aos 15 e 30 dias de rebrota. No Experimento 1, a Alfagraze mostrou menor altura (19 cm), comprimento de entrenó (1,4 cm) e acessibilidade da gema apical (15,3 cm). As cultivares tipo-pastejo não diferiram significativamente quanto ao diâmetro do hipocótilo subterrâneo (3,5 mm), na média de idade, e aos 120 dias de idade apresentaram menor número de folhas (56/planta) e hastes axilares (2,5/planta) e acúmulo de massa seca aérea (MS = 0,99 g/planta) em relação à Crioula. Aos 150 dias de idade, a Alfagraze teve menor acúmulo de massa seca aérea (0,86 g/planta) em relação às outras cultivares (1,8 g/planta). No Experimento 2, a Alfagraze apresentou maior número de folhas (172/planta) comparado à média de ABT 805 e Crioula (114/planta). Os caracteres com maior contribuição relativa para divergência genética foram o número de folhas aos 120 dias de idade (Experimento 1), 15 e 30 dias de rebrota (Experimento 2), totalizando 71,5%. A maior distância euclidiana média foi entre Alfagraze e Crioula (d = 12,3) e a menor, entre ABT 805 e Crioula (d = 8,92). Em estádio juvenil, é possível detectar em alfafa alguns mecanismos de evitamento ao pastejo, como pequena altura de planta, menor acessibilidade da gema apical e entrenó curto, bem como um dos mecanismos de tolerância ao pastejo, que é o aumento no número de folhas após o corte. Para estes caracteres a seleção precoce é possível e a Alfagraze pode ser utilizada como testemunha.

The aim of this work was to propose a methodology for commercial classification of gerbera´s capitulum based on the trans flowers overlap coefficient. Three to eight capitula of twenty-eight cultivars of gerbera cut flower and seven non-commercial accesses were used. The width measurement of the trans flowers group (internal ray flower) as well as the sum of the width of the trans and ray flowers (external ray flower) groups were taken from each capitulum. The average of each access and the overlap coefficient were calculated (CS = width of the trans flowers group / Σ of the width of the trans and ray flowers groups) and submitted to the multivariate analysis, to verify the grouping by the average Euclidian distance matrix. It is proposed that gerberas with CS= 0.01 to 0.15 be classified as simple, CS= 0.16 to 0.40 as semi-double and CS superior to 0.41 as double. The overlap coefficient (CS) can be used to systematize the classification of the gerbera capitula, reducing the divergences in the classification and the subjectivity in the decisions of producers, florists and breeders. Objetivou-se neste trabalho propor uma metodologia para classificação comercial dos capítulos de gérbera com base no coeficiente de sobreposição das flores trans. Foram utilizados três a oito capítulos de vinte e oito cultivares de gérbera com aptidão para corte e sete acessos não comerciais. Em cada um dos capítulos realizou-se a medição da largura do conjunto das flores trans (flores do raio interno) e a soma da largura do conjunto das flores trans e do raio (flores do raio externo). Com isso, calcularam-se os coeficientes de sobreposição das flores trans (CS= largura do conjunto das flores trans / Σ da largura do conjunto das flores trans e do raio) e submeteram-se os dados à análise multivariada, com a finalidade de verificar o agrupamento mediante matriz de distância euclidiana média. Propõe-se que gérberas com CS= 0,01 a 0,15 sejam classificadas como simples, CS= 0,16 a 0,40, semidobradas e CS superior a 0,41, dobradas. O coeficiente de sobreposição pode ser utilizado para sistematizar a classificação dos capítulos de gérbera, reduzindo as divergências e a subjetividade nas decisões de produtores, floricultores e melhoristas.

This study was carried out with the objective of describing the aerial and underground organs of birdsfoot trefoil [Lotus corniculatus (São Gabriel and ARS-2620 cultivars)] and big trefoil [Lotus uliginosus (Maku cultivar)]. The plants were cultivated in pots and harvested at 150 and 210 days after sowing. Stems, leaves and roots were prepared in according to conventional anatomical techniques. The anatomical structures of L. corniculatus and L. uliginosus differed in terms of pith cell integrity, starch content in the parenchyma root cell and underground stem cortex. The leaves were amphistomatic, with phenolic idioblasts, small vascular bundles and few conducting elements. The underground system was diffuse, with adventitious shoots that grew in two directions, had no cataphylls, emerged from the ground, and gave rise to aerial stems. The morphological characteristics of the shoot system of both species matched the recent descriptions of soboles.

O trabalho foi conduzido com o objetivo de verificar a resposta de uma pastagem de capim-tifton à adubação com chorume suíno (CS). O chorume suíno foi aplicado após os cortes em 15/10/2003 (emparelhamento), 24/11/2003, 10/1/2004 e 25/2/2004 nas doses de: 0, 15, 30 e 45 m³/ha/corte, totalizando 0, 60, 120 e 180 m³/ha na primavera-verão. Em 10/4/2004, foi realizado o último corte, quando não foi mais aplicado chorume suíno. A maior produção de MS (2.232 kg/ha) foi obtida no segundo corte (janeiro de 2004), com 30 m³/ha, 347% superior à obtida sem aplicação de chorume suíno. A resposta da produção total de MS à adubação com chorume suíno foi quadrática e resultou em produções de 1.397 (sem CS), 2.971 (15 m³), 4.696 (30 m³) e 4.714 (45 m³) kg/ha. A eficiência (24,5 kg MS/m³/ha) do chorume suíno não diferiu entre as doses aplicadas, mas variou de 5,6 a 49,7 kg MS/m³/ha entre os cortes. A extração máxima de nitrogênio foi de 28 kg N/ha (30 m³ ) e a recuperação de nitrogênio variou de 2% (quarto corte) a 12% (segundo corte). Os teores de PB e FDA foram afetados pela aplicação de chorume suíno e pela data de corte e variaram de 8,3 (sem chorume) a 10,7% (30 m³) no primeiro corte e de 45,9 (sem chorume) a 42,8% (45 m³) no último corte. A aplicação de chorume suíno é uma alternativa para aumentar a produção de pastagens de capim-tifton 85. Sugere-se a dose de 30 m³/ha como valor-referência para aplicação depois de cada corte ou pastejo. The work was carried out with the aim to verify the response of a cv. Tifton 85 pasture, in Depressão Central of Rio Grande do Sul state, to pig slurry (PS) fertilization, in the rates of 0, 15, 30 and 45 m³/ha/cutting, between October/03 and February/04, totalizing 0, 60, 120 e 180 m³/ha in the spring-summer. The PS was applied after cuttings, in: 15/10/2003 (uniformizing cutting), 11/24/2003, 1/10/2004 and 2/5/2004. The last cut was done in 4/10/2004 and then it was not applied PS. The highest production (2,232 kg DM/ha) was obtained in the second cutting (January/2004), with 30 m³/ha, a 347% higher than control. The total DM production response as function to PS was quadratic, being obtained 1,397 (without PS), 2,971 (15 m³), 4,696 (30 m³) and 4,714 (45 m³) kg/ha. The PS efficiency did not differ between the rates (24,5 kg DM/m³/ha) but it varied between cuttings, from 5.6 a 49.7 kg DM/m³/ha. The highest N extraction was 28 kg N/ha (30 m³) and the N recovery varied from 2% (fourth cutting) to 12% (second cutting). The CP and ADF content were affected by fertilization and cutting date, varying between 8.3 (without CS) to 10.7% (30 m³) in the first cutting and 45.9 (without PS) to 42.8% (45 m³) in the last cutting, respectively. The PS application is an alternative to increase the pasture production of cv. Tifton 85, being suggested the 30 m³/ha/cutting as reference-value.

Este trabalho foi conduzido com o objetivo de verificar o efeito da fertilização com dois tipos de camas sobrepostas de suínos (CSS), à base de casca de arroz (CA) e maravalha (MA), sobre a produção de uma pastagem natural, com predomínio de Axonopus sp. e Paspalum sp., sobressemeada com leguminosas (cornichão e trevo-branco). As camas sobrepostas foram aplicadas em quantidades equivalentes a 180, 360, 540 e 720 kg/ha de P2O5, constituindo quatro níveis de cama de casca de arroz (30, 60, 90 ou 120 t/ha) e quatro níveis de cama de maravalha (20,6; 41,2; 62,2 ou 82,8 t/ha). Foram incluídos dois tratamentos-testemunha: 180 kg/ha de superfosfato triplo (SFT) e ausência de adubação (AA). A sobressemeadura das leguminosas foi realizada em maio de 2004 e, a partir de agosto de 2004, foram realizados nove cortes da pastagem, a cada seis semanas. As maiores produções de matéria seca (MS) anuais (setembro/2004 a agosto/2005) com as aplicações de cama de casca de arroz foram obtidas nos níveis 30 e 60 t/ha e, com cama de maravalha, nos níveis 62,2 e 82,8 t/ha, que resultaram em produções de MS de 8.083 e 8.276 kg/ha, superiores às obtidas com superfosfato triplo (4.091 kg MS/ha) e sem adubação (3.071 MS kg/ha). A produção de MS de trevo-branco aumentou linearmente no outono e no inverno, de acordo com os níveis de adubação com cama de maravalha, mas não variaram com a adubação com cama de casca de arroz. O efeito fertilizante varia entre os tipos de cama sobreposta, que podem influenciar a composição botânica de pastagens mistas de leguminosas-gramíneas. This work aimed to evaluate the effect of two swine deep beddings (SDB): rice husk (CA) and sawdust coarse (MA) on the production of natural pasture. The predominant species in this pasture were Axonopus sp. and Paspalum sp. that was sod-seeded with the forage legumes birdsfoot trefoil and white clover. The SDBs were applied in amounts equivalent to 180, 360, 540, and 720 kg/ha of P2O5. In order to achieve the target P application, different levels of CA (30, 60, 90, and 120 t/ha) and MA (20.6; 41.2; 62.2; and 82.8 t/ha) were applied. Two control treatments were used: mineral fertilization (180 kg/ha of triple superphosphate, TSP) and no fertilization (AA). The legumes were sod-seeded in May/2004. After August/2004, the plants were cut every six weeks and nine cuts were performed. The highest annual (September/2004 to August/2005) dry matter (DM) production was obtained with 30 and 60 t/ha of CA or 62.2 and 82.8 t/ha of MA, with DM productivity ranging from 8,083 to 8,276 kg DM/ha. This productivity was greater than the one obtained with both TSP (4,091 kg DM/ha) and AA (3,071 kg DM/ha). The white-clover DM production increased linearly in the fall and in the winter seasons, as a function of MA and did not change with the CA rates. The results indicated that the CSS type (CA or MA) affects the fertilizing effect of these manures, influencing the production and the botanical composition of the pastures, specially the proportion of grasses and legumes.

Este trabalho foi realizado com o objetivo de verificar a resposta de uma pastagem natural na Depressão Central do Rio Grande do Sul à adubação com chorume suíno nas doses de 0, 15, 30 e 45 m³/ha, equivalentes a 76,8; 153,7 e 230,5 kg N/ha/corte depois de cada um dos quatro cortes, realizados no período de outubro de 2003 e fevereiro de 2004, totalizando 0, 60, 120 e 180 m³/ha de chorume. A massa seca (MS) da pastagem aumentou de forma linear de acordo com as doses de chorume. Na pastagem testemunha, com aplicação de 45 m³/ha/corte, houve aumento de 108% na produção de MS (1.137 kg/ha/corte; 4.549 kg/ha no total dos cortes) e de 42% na altura da pastagem (21 cm) e redução de 8% no conteúdo de fibra em detergente ácido (FDA) (41,8%). A eficiência da aplicação do chorume foi, em média, de 16,9 kg MS/m³/corte. Com as aplicações do fertilizante, verificou-se aumento na concentração de nutrientes no solo (máximo: K = 200 mg/L; P = 52 mg/L; Ca = 1,8 cmol c/dm-3; Mg = 1,4 cmol c/dm-3). A dose de 30 m³/ha/corte pode ser um valor-referência para as pastagens naturais na primavera-verão.

Este trabalho foi realizado com o objetivo de comparar cultivares de Lotus spp. de diferentes hábitos de crescimento (L. corniculatus: São Gabriel - semi-ereto; ARS2620 - prostrado; L. uliginosus: cv. Maku - decumbente) cultivados em vasos e submetidos a diferentes alturas (4 - 8 cm) e freqüências (quinzenal - mensal) de corte do 95º ao 233º dia de idade. As maiores produções de massa seca (g/planta) foram obtidas com cortes mensais a 8 cm (Maku = 13,3; S. Gabriel = 11,5; ARS2620 = 7,3). Em níveis intermediários (mensal - 4 cm; quinzenal - 8 cm), o cultivar Maku foi superior aos demais, enquanto, em cortes quinzenais (4 cm), não houve diferença entre os cultivares. O cultivar ARS2620 apresentou menor estatura e maior cobertura verde residual após os cortes. Na condição residual após o último corte, o cultivar Maku superou os demais quanto ao diâmetro da coroa e às produções de MS da raiz primária, subterrânea, aérea e de sóboles. Todos os cultivares foram favorecidos pelo manejo menos intenso, mas apresentaram mecanismos compensatórios ao serem manejados com cortes baixos em menor freqüência ou com cortes freqüentes, mas menos intensos. Os três cultivares apresentaram caules subterrâneos sobolíferos. A sobrevivência do cultivar São Gabriel e o sistema subterrâneo de Lotus spp. foram comprometidos em cortes intensos e freqüentes. This work aimed to compare Lotus spp. cultivars with different growth habits (L. corniculatus: cv. São Gabriel, semi-erect, cv. ARS2620, prostrate, and L. uliginosus: cv. Maku, decumbent), submitted to different height (4 - 8 cm) and cutting frequencies (15 d and 30 d), between the 95th and 233rd days old, grown in pot. Greater DM production (g. plant-1 of DM) was obtained under monthly cutting at 8 cm (Maku = 13.3; S. Gabriel = 11.5; ARS2620 = 7.3). Maku surpassed the others when intermediate levels (monthly cutting-4 cm; fortnighly cutting-8 cm) were used; harvests every 15 d and at 4 cm resulted in no difference among cultivars. The cv. ARS2620 showed the lowest height and the highest residual green canopy after defoliation. After the last cut, the cv. Maku overcame the other cultivars regarding crown diameter, DM of taproot, DM of soboles, DM of underground roots, and shoots. Lenient management favoured all the cultivars but they showed compensatory mechanism when they were submitted to intense and less frequent cutting or under frequent and less intense cutting. The three cultivars showed subterraneum stems of sobole type. The persistence of cv. S. Gabriel and the underground system of Lotus spp. were affected under intense and frequent cutting.

This work aimed to evaluate the effect of the cutting height (10 cm and 20 cm) and cutting interval (30 days and 45 days) on the seed production of dallisgrass cultivated under field conditions. Plants were cut between September/2003 and June/2004, nine and six times, for the 30 d and 45 d cutting interval, respectively. Seed harvests were performed on 19/11/2004 (44 g of seeds/row) and 17/12/2004 (15.8 g of seeds/row). There was significant effect of the cutting management in the seed production and germination, with greater seed yield in the 10 cm cutting height (47.9 g of seeds/row) compared to 20 cm cutting height (41 g of seeds/row), and to 45 d cutting interval (50.3 g of seeds/row) compared to 30 d cutting interval (38.7 g of seeds/row). Panicle number was the principal seed production component. For the 1st harvest, the seed germination was superior at the 30 d cutting interval (12.4%) compared to 45 d cutting interval (6.6%); at the 2nd harvest, seed germination was higher in the 10 cm cutting height (5.6%) compared to 20 cm cutting height (3.3%) and to 30 d cutting interval (5.3%) compared to 45 d cutting interval (3.6%). The major limitation for dallisgrass seed production was its continuous flowering and the short interval between the full flowering and the spikelet abscission initiation, which caused different maturation degrees in the lot of harvested seed.

Objetivou-se caracterizar a variabilidade existente e estimar a divergência genética de uma coleção nuclear de trevo-branco formada por 78 acessos. Dezessete plantas de cada acesso foram caracterizadas com base em nove parâmetros (oito morfológicos e um agronômico): estatura das plantas, hábito de crescimento, intensidade de florescimento, comprimento de estolão, número de nós por estolão, comprimento dos entrenós, diâmetro de estolão, produção total de MS e área foliar por planta. Pela estimativa da distância de Mahalanobis, os acessos 1 (PI 195534) e 10 (PI 419325) apresentaram a maior distância (45,4) e os acessos 58 (PI 180491) e 68 (PI 197830), a menor distância (0,19). A área foliar foi a característica com maior contribuição relativa para divergência genética (24%), seguida pela estatura da planta (20%), pela intensidade de florescimento (19%) e pela produção total de MS (15%). A análise de correlação linear simples entre as variáveis mostrou correlação positiva e significativa entre estatura e área foliar (0,92), assim como entre comprimento de estolão e comprimento de entrenós (0,90). This work aimed to evaluate morphological features of the white clover core collection obtained from the United States Department of Agriculture (USDA), represented by 78 accessions, in order to characterize the existent morphological variability and to estimate the genetic divergence, using nine characters (eight morphological and one agronomic). Seventeen plants from each access were evaluated individually at the Experimental Station of the Universidade Federal do Rio Grande do Sul in Eldorado do Sul and characterized in relation to the following characters: plant height, growth habit, flowering intensity, stolon length, node number per stolon, internode length, stolon diameter, total dry matter yield and leaf area per plant. Using the estimate of Mahalanobis´ distance, the results showed that the accessions 1 (PI 195534) and 10 (PI 419325) presented the greatest distance (45.4), while the accessions 58 (PI 180491) and 68 (PI 197830) presented the smallest distance (0.19). The leaf area was the character with the largest individual relative contribution to the genetic divergence (24%), followed by plant height (20%), flowering intensity (19%) and total dry matter yield (15%). There was a positive and highly significant correlation between plant height and leaf area (0.92) and also between stolon length and internode length (0.90).

Foram comparadas, neste estudo, a produção e a seletividade animal de cultivares de capim-elefante em condições de clima frio, em Lages, Santa Catarina. O ensaio constou de 12 cultivares (Mineiro X-23A, Mineiro, Taiwan A-144, CAC-262, Mole da Volta Grande, Teresópolis, Vrukwona, Merckeron Pinda, Turrialba, Porto Rico, Taiwan A-14 e Cameroon), estabelecidas em parcelas de 17,5 m², em um delineamento de blocos casualizados, com três repetições. Cada parcela foi formada por sete linhas espaçadas 0,50 m, considerando-se como área útil as três linhas centrais. Os cortes para avaliação da produção de forragem foram realizados em janeiro, março e maio de 1985 e 1986, sempre que as plantas atingiram cerca de 1,5 m de estatura. A avaliação da seletividade animal foi realizada em janeiro e março de 1987, após o pastoreio, mediante notas atribuídas ao resíduo de forragem na parcela (método Botanal). A análise da variância mostrou efeito significativo de anos e de cultivares para a produção total de forragem, não havendo efeito significativo para a interação desses fatores. Na média dos dois anos, o potencial de produção variou entre 11 t e 21 t MS/ha. Observou-se uma redução de 27% na produção de forragem no segundo ano, com média geral dos cultivares de 12.116 kg MS/ha, que foi significativamente inferior à do ano anterior (16.662 kg MS/ha). O cv. Mineiro X-23A foi o que apresentou a maior produção de forragem, superando 20 t MS/ha. O cv. Porto Rico destacou-se pela maior proporção de folhas e maior seletividade pelos animais e o cv. CAC-262, pela maior estabilidade, ou seja, menor variância nos dois anos de avaliação.

Este trabalho foi conduzido com o objetivo de caracterizar agronomicamente genótipos de cornichão (Lotus corniculatus L.), incluindo oito populações do cv. São Gabriel, um cultivar rizomatoso (cv. ARS-2620) e um cultivar sem rizomas (cv. Trueno). Plantas individuais foram cultivadas e submetidas a sete cortes em condições de campo, durante um ano, em Passo Fundo, Rio Grande do Sul, Brasil. Os genótipos apresentaram variabilidade quanto ao comprimento de entrenós, estatura, diâmetro, comprimento de legumes, produção de forragem e valor nutritivo. Na média geral, as populações e o cv. Trueno foram cerca de 50% mais produtivos em relação ao cv. ARS-2620. Os genótipos apresentaram entre 80 e 100% de sobrevivência. O conteúdo de proteína bruta reduziu de 21,8% (estádio vegetativo) para 11,2% (estádio de frutificação). A média geral de fibra detergente ácido foi de 24,2% e a de fibra detergente neutro variou entre 55,3 e 58,8%. This work was carried out to characterize agronomically birdsfoot trefoil (Lotus corniculatus L.) genotypes, including eight populations derived from the cultivar São Gabriel, one rhizomatous cultivar (ARS-260) and one cultivar without rhizomes (Trueno). Individual plants were submitted to seven cuts under field conditions during one year, at Passo Fundo, Rio Grande do Sul, Brazil. The genotypes showed variability relative to internode lenght, height, diameter, legume lenght, forage production and nutritive value. On the average, the populations and the cv. Trueno were about 50% more productive than the cv. ARS-260. The genotypes presented a survival range from 80% to 100%. The crude protein content decreased from 21.8 (vegetative stage) to 11.2% (fruiting stage). The overall mean for acid detergent fiber was 24.2% and the neutral detergent fiber ranged from 55.3% to 58.8%.

Caracteres morfologicos e fenologicos sao utilizados na selecao, cruzamentos e descricao de genotipos, sua instabilidade frente a alteracoes ambientais pode determinar o seu valor na etapa de protecao de cultivares. Este trabalho foi desenvolvido com o objetivo de verificar a expressao de descritores morfologicos e fenologicos e, consequentemente, a dissimilaridade entre cultivares de aveia-branca (Avena sativa L.) em dois periodos de cultivo. Para isso, cinco cultivares, protegidas e oriundas de quatro obtentores e, aqui, codificadas (G1, G2, G3, G4 e G5), foram semeadas dentro do periodo recomendado para a cultura no sul do do Brasil (outono-hibernal) e fora desse periodo (hiberno-primaveril), com intervalo de quarenta dias. O experimento foi estabelecido em campo, em blocos casualizados, com tres repeticoes. As cultivares foram avaliadas quanto a 42 descritores (15 quantitativos e 27 qualitativos). Os dados quantitativos foram submetidos a analise de variância, seguida da comparacao de medias, e a analise multivariada, por meio da geracao da distância euclidiana media. Os dados qualitativos foram submetidos a determinacao da moda, seguida da obtencao do indice de similaridade. A relacao entre as cultivares foi ilustrada por meio de dendrogramas. Foi calculado o indice de estabilidade dos descritores. A interacao genotipo x ambiente foi observada em 28 descritores. A estabilidade de expressao, a alteracao no periodo de cultivo, foi maior nos descritores qualitativos (44%), quando comparada aos quantitativos (7%). Os descritores qualitativos mais estaveis foram: cor do lema, pilosidade do no superior, posicao da folha-bandeira, pilosidade da base do grao, comprimento dos pelos basais do grao e comprimento da raquila. O descritor quantitativo mais estavel foi o comprimento da folha-bandeira. O atraso no periodo de cultivo da aveia-branca, de outono-hibernal para hiberno-primaveril, reduz o ciclo da cultura e modifica a expressao da maioria dos descritores, alterando a dissimilaridade fenotipica entre cultivares.

This study aimed to evaluate tough lovegrass leaf and root extracts antimicrobial activity. The extracts (plant material: solvent, 1:10) were prepared by maceration with methanol:water (1:1) during ten days followed by a concentration in a rotary evaporator under reduced pressure. The extracts were resuspended in water containing 1% of dimethylsulfoxide (DMSO) to obtain a final concentration of 100 mg/mL and then filtered through a sterilizing membrane with 0.22μm. The antibacterial activity of the leaf and root extracts were evaluated against pathogenic and phytopathogenic bacteria by agar well diffusion and microdilution broth methods for the minimum inhibitory concentrations (MIC) determination. The antifungal activity of tough lovegrass leaf and root extracts were evaluated by micelial growth inhibition and conidial germination inhibition. The extracts presented low antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Xanthomonas translucens, but the leaf extracts presented significant antifungal activity against the phytopathogenic fungus Drechslera tritici-repentis. The results support the continuity of the study in improving the effectiveness of the active extract for a possible use in pharmacology and agronomy and in attempting to determine the probable active antimicrobial compound.

The phytochemical profile and antimicrobial activity of cultivar (cv.) extracts of Lotus uliginosus (cvs. Trojan and Serrano), L. tenuis (cv. Larrañaga) and L. corniculatus (cv. São Gabriel) were investigated. The phytochemical analysis revealed tannins, coumarins and flavonoids in all extracts, with variations among cultivars, showing genotypic variability. By High Performance Liquid Chromatographic method, the cvs. Larrañaga and São Gabriel showed the highest percentage of catechin and epicatechin, respectively, and presented rutin, which was not detected in the other ones. These genotypes showed antifungal activity but not antibacterial one. The cv. Larrañaga inhibited the mycelia growth of Alternaria sp. and Fusarium graminearum while the cv. São Gabriel was active only against Alternaria sp. The cultivars showed the greatest amounts of secondary metabolites and demonstrated significant activity against filamentous fungi. The results provide a direction for further research about pharmacological use of Lotus spp. O perfil fitoquímico e a atividade antimicrobiana de extratos de cultivares (cvs.) de Lotus uliginosus (cvs. Trojan e Serrano), L. tenuis (cv. Larrañaga) e L. corniculatus (cv. São Gabriel) foram investigados. A análise fitoquímica revelou taninos, cumarinas e flavonoides em todos os extratos, com variação entre os cvs., demonstrando variabilidades genotípicas. Pelo método de Cromatografia Líquida de Alta Eficiência, os cvs. Larrañaga e São Gabriel apresentaram os maiores percentuais de catequina e epicatequina, respectivamente, e apresentaram rutina, que não foi detectada nos demais. Tais genótipos apresentaram atividade antifúngica, mas não mostraram atividade antibacteriana. O cv. Larrañaga inibiu o crescimento micelial de Alternaria sp. e Fusarium graminearum enquanto o cv. São Gabriel foi ativo somente contra Alternaria sp.. Os cultivares que apresentaram as maiores quantidades de metabólitos secundários, demonstraram atividade significativa contra fungos filamentosos. Os resultados fornecem indicativos para futuras pesquisas sobre a utilização farmacológica de Lotus spp.

Condensed tannins are formed by monomers of procyanidins and prodelfinidins, where the proportion and concentration of their monomers varies according to the plant species and environmental conditions. In Lotus spp., condensed tannins prevent tympanism in ruminants that feed on them. This study aimed to evaluate the concentration of procyanidins and their monomers, catechin and epicatechin in the genotypes of Lotus L. grown in soil with different saturations of aluminum. A two-factor (genotype × Al saturation) assay was performed, where the genotypes São Gabriel, Ganador, and UFRGS (Lotus corniculatus L.); Serrano (Lotus uliginosus); and El Rincón (Lotus subbiflorus) were cultivated in soil with an Al saturation of 0-20%. The procyanidins were evaluated using high-performance liquid chromatography, which was previously validated for catechin and epicatechin. The concentration of procyanidins and the proportion of epicatechin:catechin were affected by the genotype × environment interaction. In L. corniculatus and L. subbiflorus, the concentration of procyanidin was significantly higher when they were grown in the soil with an Al saturation of 20% compared to that when they were grown in the soil with 0% Al saturation, but the opposite effect was observed in L. uliginosus. The proportion of epicatechin:catechin decreased in plants grown in soil without Al, and only the UFRGS genotype maintained a similar proportion under both the soil acidity conditions. The predominant monomer was epicatechin, which varied from 57% to 75% according to the soil in which the plants were grown.

The effect of the aluminum in root has been evaluated by linear and weight measurements, but remains to be understood about the influence of this element on branching configuration of the root system. This study had the objective to assess the aluminum toxicity in roots of 21-day-old seedlings of three forage legumes, Adesmia latifolia, Trifolium repens and T. pratense (Fabaceae), by topological analysis. The legumes were grown in Oxisol treated or not with dolomite lime, which resulted in two Al saturation and pH: (a) Al= 0 %, pH= 6.2; (b) Al= 16 %, pH= 4.8. Number of first-order roots, external links (magnitude), total links in the longest unique path (altitude), total links in the primary root (altitude of primary root), total exterior path length, total links, internal links, branching points, and proportion of branching in primary root were determined. The topological variables were significantly reduced by Al, regardless to the legumes. The altitude-slope on magnitude showed that there was a more randomized branching configuration in seedlings grown in acid soil. A. latifolia was the most plastic species, with reducing of the slopes from 0.9758 (Al-absence) to 0.6858 (Al-presence), showing herringbone and randomized branching, respectively. The effect of aluminum (Al) on roots has been evaluated based on linear and weight measurements, but how this element influences the branching configuration of the root system remains unknown. The objective of this study was to assess aluminum toxicity in the roots of 21-day old seedlings from three forage legumes using topological analysis: Adesmia latifolia, Trifolium repens and T. pratense. The legumes were grown in dystrophic Red Latosol that had either been treated or not treated with dolomitic lime. This resulted in two Al saturation and pH treatments: (a) Al= 0%, pH= 6.2; and (b) Al= 16%, pH= 4.8. The following attributes were determined: number of first-order roots, external links (magnitude), total links in the longest unique path (altitude), total links in the primary root (primary root altitude), total exterior path length, total links, internal links, branching points and proportion of branching in the primary root. The topological variables were significantly reduced by Al for all of the legume species. There was a more randomized or dichotomous branching configuration in the seedlings grown in acid soil and A. latifolia was the most plastic of the species.

This is the first report on chemical compounds in tough lovegrass, an allelopathic plant considered to be the most abundant invasive plant in the rangelands of Southern Brazil.