35 research outputs found
Genetic parameters and predicted gains with selection of interspecific hybrids of Paspalum for seed production
The aim of this study was to estimate the genetic parameters and predicted gains with selection of interspecific hybrids of Paspalum in relation to seed production traits Data were analyzed in randomized block design, with 23 genotypes arranged into ten blocks, according to the methodology of mixed models by the REML/BLUP procedure. The traits considered in the study were: number of total tillers/plant, number of reproductive tillers/plant, number of racemes/inflorescence, number of seeds/inflorescence, weight of a thousand seeds and seed production. Variability among genotypes, high heritability (>0.50), except total tillers (0.44) and number of racemes (0.36), and high accuracy (>0.90) were identified for all traits. The hybrids 10E5052, 10E4026, 10E507, 10E4025 and 10E40104 are among the top ten because they have high genetic values in three or more traits, indicating that these genotypes should be recommended for direct use in planting or potential parents to be used in new crosses
Agronomic performance of interspecific Paspalum hybrids under nitrogen fertilization or mixed with legumes
Nitrogen supply and mixtures with legumes affect agronomic performance of pas- tures, and both practices can guide breeding decisions in Paspalum hybrids. The goals of this study were: (a) quantify herbage accumulation (HA), leaf accumulation (LA), cold tolerance, and N use efficiency (NUE) in P. plicatulum Ă P. guenoarum hybrids subjected to N fertilization or grown in a mixture with legumes; (b) compare the grassâlegume system to a grassâN fertilizer system; and (c) select the best hybrid for future cultivar releases. A randomized complete block design with three repli- cations and a split-plot treatment arrangement was used for 2 yr, with five N rates (0, 60, 120, 240, and 480 kg N haâ1) and a grassâlegume mixture [grass + white clover (Trifolium repens L.) + birdsfoot trefoil (Lotus corniculatus L.)] as whole plots, and six genotypes as subplots (hybrids: 1020133, 102069, 103084, 103061; and controls: P. guenoarum âAzulĂŁoâ and Megathyrsus maximus âAruanaâ). Higher N rates increased HA, LA, and cold tolerance. Higher NUE was obtained between 60 and 120 kg N haâ1. In the grassâlegume mixture HA was similar to the rates of 60 and 120 kg N haâ1. Hybrid 1020133 had HA similar to the controls, LA greater than Aruana, and greater cold tolerance and NUE at 60 kg N haâ1 than AzulĂŁo and Aruana. Hybrid 1020133 should be selected for further animal performance stud- ies. The agronomic performance of perennial pastures can be improved through N management, and NUE should be a selection criterion in forage breeding
Management of consecutive cuts in the production and quality of wintergreen paspalum seeds
ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest
Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ
Agricultura de precisão em trigo: variabilidade espacial e temporal da produção de biomassa e sua relação com a produtividade de grãos
Agricultura de precisão em trigo: variabilidade espacial e temporal da produção de biomassa e sua relação com a produtividade de grãos
Desempenho forrageiro e sementeiro de um grupo elite de hĂbridos intraespecĂficos de Paspalum notatum
Previous studies for agronomy characterization in a P. notatum collection, selected the genotypes âAndrĂ© da Rochaâ, âBagualâ, âV4â, â83Nâ, â95Nâ and â36Nâ to be used in the Bahiagrass breeding program of UFRGS. Since the sexual tetraploids: C44X, Q4188 and Q4205 were available, these plants were used in crosses as mothers with the selected ecotypes as pollen donor. The progeny was evaluated for forage yield and had their reproduction mode identified. An elite group of nine intraspecific hybrids plus the controls âBagualâ, âV4â and âPensacolaâ were arranged in a RCBD with three replications. There were evaluated over years and seasons for forage components and for two years for seed components, germination, viable seeds and dormancy. This study aimed: i) select superior agronomic P. notatum intraspecific hybrid for forage and seed production; ii) determine forage components of genotypes swards, cold tolerance and regrowth vigor; iii) characterize seed yield components, physiological and physical quality; iv) identify the forage components most related to herbage mass production; v) identify the variables most related to seed production; vi) provide information about reproductive phenology. Evaluations across harvest were performed during 2016/17 and 2017/18. Each time 70% of all genotypes reached 95% of luminous intercept to target the seed production, plots were deferred from the cuts when the beginning of the internode elongation was observed. Furthermore, the seed components variables were assessed in the harvest time. There were differences among genotypes, years and seasons for most of the variables assessed. The genotypes showed different performances for the traits allowing different patterns of seasonal forage yield, flowering period, seed yield and quality. The hybrids âC15â, âC18â, â336â, â437â demonstrated desirable aspects in forage distribution, larger annual production being equal or better than âBagualâ and âV4â. âBagualâ and hybrids âC18â, â336â stood out for seed production. âPensacolaâ showed poorly forage yield and seed performance. It was infected with high weeds not being a good check option. The hybrid âC15â had a reasonable seed production in the first year and badly in the second year. The reason for that was negatively affected by the deferred management. Due to its highly forage yield and apomixis, more studies need to be done to establish the management to improve seed yield and qualityEstudos anteriores para caracterização agronĂŽmica em uma coleção P. notatum selecionaram os genĂłtipos 'AndrĂ© da Rocha', 'Bagual', 'V4', '83N', '95N' e '36N' para serem utilizados no programa de melhoramento genĂ©tico da UFRGS. Uma vez disponĂveis os os tetraplĂłides sexuais: C44X, Q4188 e Q4205, essas plantas foram utilizadas como mĂŁes em cruzamentos com os ecĂłtipos selecionados os quais foram utilizados como doadores de pĂłlen. A progĂȘnie foi avaliada quanto ao rendimento de forragem e teve seu modo de reprodução identificados. Um grupo de elite de nove hĂbridos intraespecĂficos de grande produção forrageira, mais os controles 'Bagual', 'V4' e 'Pensacola' foram arranjados em um delineamento de blocos completos casualizados com trĂȘs repetiçÔes e avaliados por anos e por estaçÔes do ano para componentes forrageiros e durante dois anos para componentes do rendimento de sementes, germinação, sementes viĂĄveis e dormĂȘncia. Este estudo objetivou: i) selecionar hĂbridos intraespecĂficos de P. notatum agronomicamente superiores para produção de forragem e sementes; ii) determinar os componentes forrageiros, tolerĂąncia ao frio e vigor de rebrota; iii) caracterizar os componentes de produção de sementes, qualidade fisiolĂłgica e fĂsica; iv) identificar os componentes forrageiros relacionados Ă produção de forragem; v) identificar as variĂĄveis relacionadas Ă produção de sementes; As avaliaçÔes ao longo da colheita foram realizadas durante 2016/17 (ano 1) e 2017/18 (ano 2), cada vez que 70% de todos os genĂłtipos atingiram 95% de interceptação luminosa. Visando a produção de sementes, as parcelas foram diferidas dos cortes quando se observou o inĂcio do alongamento dos entrenĂłs, e as variĂĄveis dos componentes das sementes foram avaliadas por ocasiĂŁo da colheita. Houve diferenças entre genĂłtipos, anos e estaçÔes para a maioria das variĂĄveis avaliadas. Os genĂłtipos apresentaram diferentes desempenhos para os caracteres, permitindo identificar diferentes padrĂ”es de produção de forragem nas estaçÔes, produtividade e qualidade das sementes. Os hĂbridos "C15", "C18", "336", "437" mostraram aspectos desejĂĄveis na distribuição de forragem, sendo a produção anual maior igual ou superior Ă de "Bagual" e "V4". "Bagual" e os hĂbridos "C18", "336" se destacaram na produção de sementes. "Pensacola" apresentou rendimento de forragem e desempenho de sementes ruim, abaixo do esperado, o que ocorreu devido Ă alta infestação de ervas daninhas, nĂŁo sendo uma boa opção de testemunha. O hĂbrido "C15" teve uma produção razoĂĄvel de sementes no primeiro ano e ruim no segundo ano uma vez que foi afetado negativamente pelo manejo de diferimento. Devido a sua alta produtividade de forragem e apomixia, mais estudos precisam ser feitos para estabelecer o manejo para melhorar o rendimento e a qualidade das sementes
Seed production and quality of Paspalum guenoarum Arech. âAzulĂŁoâ ecotype under different cutting management on the second year of crop
O objetivo deste trabalho foi avaliar o efeito do nĂșmero de cortes na produção e qualidade de sementes de Paspalum guenoarum ecĂłtipo âAzulĂŁoâ no segundo ano de cultivo. Foram avaliados quatro tratamentos de corte: zero (testemunha), um, dois e trĂȘs cortes quando o dossel das plantas atingia altura de 40 cm. O delineamento experimental foi de blocos completos casualizados, com quatro repetiçÔes. As parcelas tinham 7,2 mÂČ (3,6 m x 2 m) com as plantas em linhas espaçadas a 0,4 m. As avaliaçÔes foram semanais de dezembro de 2013 a março de 2014. As variĂĄveis estudadas foram: nĂșmero de perfilhos/planta, nĂșmero de perfilhos reprodutivos/planta atravĂ©s de amostragens nĂŁo destrutivas. O nĂșmero de racemos/inflorescĂȘncia, nĂșmero de sementes/inflorescĂȘncia, nĂșmero de sementes/racemo, peso de mil sementes, rendimento de sementes/ĂĄrea, germinação e Ăndice de velocidade de germinação, foram obtidos atravĂ©s de amostragens destrutivas apĂłs a colheita das sementes. As mĂ©dias foram comparadas pelo teste de Tukey a 5%. O tratamento de um corte (719 kg.ha-1 de sementes e 75% de plĂąntulas normais) nĂŁo diferiu da testemunha, nĂŁo apresentando impactos negativos na produção e qualidade de sementes. Entretanto, a partir de dois cortes, houve a diminuição do nĂșmero de perfilhos reprodutivos/planta, adiamento da colheita e redução da produção de sementes. A realização de um corte permitiu a produção de boa quantidade de forragem (2500 kg.ha-1 de MS) sem prejudicar o rendimento e a qualidade das sementes.This study was aimed to evaluate the effect of the number of cutting in seed production and quality of Paspalum guenoarum, âAzulĂŁoâ ecotype on the second year of crop. Treatments of zero (control), 1, 2, and 3 cuts were evaluated. The experimental design was a completely randomized block with four repetitions. The plots were of 7.2 mÂČ (3.6 m x 2 m) with plants in 0.4 m rows spacing. Assessments were performed weekly from December, 2013 to March, 2014. The studied variables were number of tillers/plant, number of reproductive tillers/plant, and number of racemes/inflorescence through nondestructive sampling. The number of seeds/inflorescence, number of seeds/raceme, weight of thousand seeds, seed yield/area, germination, and germination speed index were obtained through destructive sampling after harvesting seeds. The means were compared by Tukey test at 5%. One cutting treatment (719 kg.ha-1 of seeds and 75% normal seedlings) doesnât differ significantly comparing to the control, so, it didnât appear negative impacts in seed production and quality. However, from two different cutting, there was a decrease in the number of reproductive tillers/plant, causing a delay harvest and reduced seed production. The achievement of one cutting allowed a utilization of good quantity of forage (2500 kg.ha-1 DM) without harming significantly the seed yield and quality
Rendimento de grĂŁos e seus componentes em diferentes cultivares de trigo afetados pela disponibilidade de nitrogĂȘnio
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Seed production and quality of Paspalum guenoarum Arech. âAzulĂŁoâ ecotype under different cutting management on the second year of crop
O objetivo deste trabalho foi avaliar o efeito do nĂșmero de cortes na produção e qualidade de sementes de Paspalum guenoarum ecĂłtipo âAzulĂŁoâ no segundo ano de cultivo. Foram avaliados quatro tratamentos de corte: zero (testemunha), um, dois e trĂȘs cortes quando o dossel das plantas atingia altura de 40 cm. O delineamento experimental foi de blocos completos casualizados, com quatro repetiçÔes. As parcelas tinham 7,2 mÂČ (3,6 m x 2 m) com as plantas em linhas espaçadas a 0,4 m. As avaliaçÔes foram semanais de dezembro de 2013 a março de 2014. As variĂĄveis estudadas foram: nĂșmero de perfilhos/planta, nĂșmero de perfilhos reprodutivos/planta atravĂ©s de amostragens nĂŁo destrutivas. O nĂșmero de racemos/inflorescĂȘncia, nĂșmero de sementes/inflorescĂȘncia, nĂșmero de sementes/racemo, peso de mil sementes, rendimento de sementes/ĂĄrea, germinação e Ăndice de velocidade de germinação, foram obtidos atravĂ©s de amostragens destrutivas apĂłs a colheita das sementes. As mĂ©dias foram comparadas pelo teste de Tukey a 5%. O tratamento de um corte (719 kg.ha-1 de sementes e 75% de plĂąntulas normais) nĂŁo diferiu da testemunha, nĂŁo apresentando impactos negativos na produção e qualidade de sementes. Entretanto, a partir de dois cortes, houve a diminuição do nĂșmero de perfilhos reprodutivos/planta, adiamento da colheita e redução da produção de sementes. A realização de um corte permitiu a produção de boa quantidade de forragem (2500 kg.ha-1 de MS) sem prejudicar o rendimento e a qualidade das sementes.This study was aimed to evaluate the effect of the number of cutting in seed production and quality of Paspalum guenoarum, âAzulĂŁoâ ecotype on the second year of crop. Treatments of zero (control), 1, 2, and 3 cuts were evaluated. The experimental design was a completely randomized block with four repetitions. The plots were of 7.2 mÂČ (3.6 m x 2 m) with plants in 0.4 m rows spacing. Assessments were performed weekly from December, 2013 to March, 2014. The studied variables were number of tillers/plant, number of reproductive tillers/plant, and number of racemes/inflorescence through nondestructive sampling. The number of seeds/inflorescence, number of seeds/raceme, weight of thousand seeds, seed yield/area, germination, and germination speed index were obtained through destructive sampling after harvesting seeds. The means were compared by Tukey test at 5%. One cutting treatment (719 kg.ha-1 of seeds and 75% normal seedlings) doesnât differ significantly comparing to the control, so, it didnât appear negative impacts in seed production and quality. However, from two different cutting, there was a decrease in the number of reproductive tillers/plant, causing a delay harvest and reduced seed production. The achievement of one cutting allowed a utilization of good quantity of forage (2500 kg.ha-1 DM) without harming significantly the seed yield and quality