ABSTRACT:In a quality control program, seed vigor evaluation is of fundamental importance for the success of the program. The objective of this project was to evaluate the efficiency of several vigor tests to evaluate the physiological quality of Brachiaria brizantha cv. 'BRS Piatã' seed lots and to preview seedling emergence in the field. Ten grass seed lots of the B. brizantha cv. 'BRS Piatã' were evaluated by the following tests: germination, first count of germination, accelerated aging (43 °C/48 hours), cold test (seeds rolled in paper towel), seed water content before and after accelerated aging, electrical conductivity (50 and 75 mL, 25 °C and readings made 2, 4, 6, 8, and 24 hours after beginning the test), speed of germination index, and seedling emergence in sand substratum in the laboratory (26 ± 3 °C) and daily seedling counts between the 7th and the 21th day after sowing. The treatment replications were distributed in the laboratory according to a completely random design with four replications. Seedling emergence in the field data were analyzed according to a randomized complete block design. Treatment means were compared by the Scott Knott test, at the 5% level of probability. The tests for germination and first germination count, seedling emergence and first emergence count in the sand, and accelerated aging are useful to assess the vigor of seed batches of the piatã grass, and provide similar evidence to the seedling emergence in the field.
The period of 21 days suggested by the Brazilian Rules for Seed Testing for the germination test of B. humidicola seeds seems too long for seed producing companies and laboratories since they depend on the results for decisions concerning the storage or the commercialization of the seed lots. So, the objective of this work was to evaluate the possibility of getting germination results of B. humidicola seeds in a shorter period. The procedures consisted in submitting the seeds to a dormancy breaking treatment and to alternating temperatures during the germination test. Seed samples of nineteen S1 and S2 seed lots were submitted to the following treatments: moistening the germination substratum with 1) deionized water (check treatment), 2) a KNO 3 (0.2%) solution, and 3) scarifying the seeds with sulfuric acid for 10 minutes. The germination test was conducted under the conditions of 1) alternating temperatures of 20 and 35 °C and 2) alternating temperatures of 15 and 35 °C both with 8 hours of light. Normal seedlings were evaluated in daily countings. The results showed that the germination test of B. humidicola seeds may be carried out under alternating temperatures of 15 and 35 °C without breaking seed dormancy with a final evaluation of the germination 10 days after the sowing of the seeds. Key words: Dormancy. Forage grass. Pasture. Temperature. ResumoO período de 21 dias recomendado pelas Regras para Análise de Sementes para o teste de germinação de sementes de B. humidicola é considerado excessivo por produtores, comerciantes e laboratórios de análise de sementes, que dependem dos resultados do teste para o controle de qualidade e a comercialização. Desta forma, o objetivo do trabalho foi avaliar a possibilidade de reduzir o período necessário para a condução do teste de germinação de sementes de B. humidicola, estabelecendo o método para superação da dormência e a temperatura ideal. Dezenove lotes de sementes comerciais S1 e S2 recém-recebidos na unidade de beneficiamento foram avaliados quanto à germinação, em quatro subamostras de 100 sementes por tratamento, constituído de: substrato umedecido com água deionizada (testemunha), substrato umedecido com KNO 3 (0,2%) e escarificação com ácido sulfúrico por 10 minutos. Para o teste de germinação, foram avaliadas duas condições de temperaturas alternadas (20-
Objetivo: O estudo analisa a relação entre habilidade gerencial e perdas do valor recuperável de goodwill. Método: Pesquisa descritiva, documental e quantitativa, com dados coletados no banco de dados economática, relatórios da administração e notas explicativas. A amostra foi composta por 148 companhias, sendo analisadas as informações do período de 2012 a 2016. Resultados: Do total de companhias que possuíam goodwill, 10,81% contabilizaram perdas, sendo que o setor de “petróleo, gás e biocombustíveis” possuía o maior número de companhias com perdas contabilizadas. Quanto à magnitude das perdas, verificou-se que o setor de “materiais básicos” apresentou o maior valor médio, seguido dos setores “tecnologia da informação” e “petróleo, gás e biocombustíveis”. Os gestores das empresas do setor de “saúde” apresentaram maiores indicadores de habilidade gerencial, seguidos pelos gestores das empresas dos setores de “consumo cíclico” e “consumo não cíclico”. Constatou-se também que os gestores mais habilidosos podem reduzir, mas não evitar as perdas do goodwill. Contribuições: O estudo analisa um fator que pode influenciar nas perdas do goodwill, mas que ainda não foi investigado no cenário brasileiro, a habilidade gerencial. Assim, contribui para a literatura fornecendo mais evidências sobre os fatores determinantes da redução do valor recuperável do goodwill.
Germinação e vigor de sementes de (25,(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30) 30 (25, 20-30, 30 and 35°C)
RESUMO -A semente recebida pelas empresas de gramíneas forrageiras, após a colheita, contém impurezas cuja remoção é realizada por máquinas de beneficiamento. Este procedimento é necessário para a obtenção de sementes dentro dos padrões de qualidade para a comercialização e a semeadura. O objetivo deste trabalho foi avaliar o efeito das etapas de beneficiamento na qualidade física e fisiológica de sementes de Panicum maximum cv. Mombaça, visando à comercialização. As sementes foram amostradas antes do processamento e após a saída da máquina de ventilador e peneiras (descarga das peneiras superior, intermediária e fundo), primeira mesa gravitacional (deriva, descarga superior e intermediária), máquina tratadora e segunda mesa gravitacional (descarga superior, intermediária e inferior). As sementes foram avaliadas quanto ao teor de água, qualidade física (pureza e peso de mil sementes) e fisiológica (germinação, primeira contagem, classificação do vigor de plântulas, envelhecimento acelerado, comprimento de plântulas, emergência de plântulas em campo e índice de velocidade de emergência). O beneficiamento de sementes, na máquina de ar e peneiras e mesa gravitacional é eficiente para o aprimoramento da qualidade física e fisiológica do lote de sementes de P. maximum cv. Mombaça. Para esta espécie o beneficiamento é necessário para atender os requisitos de pureza e germinação estabelecidos pelos padrões de comercialização nacional de sementes.Palavras-chave: Panicum maximum. Germinação. Vigor. Processamento. Pureza. Gramíneas forrageiras.ABSTRACT -Seeds received by forage-grass companies after harvesting contain impurities which are removed by processing machines. This procedure is necessary to obtain seeds which are within the standards of quality for marketing and sowing. The aim of this work was to evaluate the effects of the processing stages on the physical and physiological quality of seeds of guinea grass cv. Mombasa (Panicum maximum), with a view to marketing. Seeds were sampled before processing and after leaving the air screen machine (output from the upper, intermediate and bottom screens), first gravity table (drift, upper and intermediate output), treating machine, and second gravity table (upper, intermediate, and lower output). The seeds were evaluated for water content, physical quality (purity and thousand-seed weight) and physiological quality (germination, first count, classification of seedling vigour, accelerated ageing, seedling length, seedling emergence in the field, and speed of emergence index). Seed processing in the air and screen machine and the gravity table is efficient in improving the physical and physiological quality of the lots of P. maximum cv. Mombasa seed. For this species, processing is necessary to meet the demands for purity and germination established by the Brazilian standards for seed marketing.
A B S T R A C TThe objective of this work was to evaluate the effect of temperature and substrate on the germination of P. volubilis seeds. Seeds harvested from 25 matrix plants were submitted, in two studies, to conditions of (i) sowing in rolled paper towel at the temperatures of 10, 15, 20, 25, 30, 35, 40, and 45 °C, for the evaluation of germination, first count of germination, germination speed index and mean time for germination, and (ii) sowing in the substrates paper towel, sand, Bioplant®, Bioplant® and micron, superfine, fine, medium and coarse vermiculite. The same evaluations mentioned in the first study were conducted at the temperature of 30 o C, as well as plant growth. The treatment replicates were distributed in a completely randomized block design and the effects of temperature were compared by polynomial regression analysis. The substrates were compared by the Scott-Knott test at 0.05 probability level. The data show that the ideal range of temperature for the germination of P. volubilis is between 25 and 30 °C. The temperature of 20 °C is the minimum for germination and those above 35 °C are lethal to these seeds. The most favorable substrate for P. volubilis seed germination is micron or fine vermiculite.Temperatura e substrato na germinação de sementes de Plukenetia volubilis L. R E S U M OObjetivou-se, neste trabalho, avaliar o efeito de temperaturas e substratos na germinação de sementes de P. volubilis. Sementes colhidas em 25 plantas matrizes foram avaliadas em dois estudos: (i) semeadura em rolo de papel nas temperaturas 10, 15, 20, 25, 30, 35, 40 e 45 ºC, avaliando-se a germinação, primeira contagem, índice de velocidade de germinação e tempo médio de germinação; e (ii) semeadura nos substratos rolo de papel, entre areia, entre Basaplant®, entre Bioplant® e entre vermiculita mícron, superfina, fina, média e grossa; conduzindo-se a 30 ºC os mesmos testes descritos no primeiro estudo e também o crescimento de plântulas. Os dados foram analisados em delineamento inteiramente casualizado com análise de regressão polinomial para a avaliação das temperaturas. Para a comparação entre os substratos utilizou-se o teste de Scott Knott, a 0,05 de probabilidade. Conclui-se que a germinação de sementes de P. volubilis deve ser conduzida nas temperaturas de 25 a 30 o C. A temperatura de 20 o C é a mínima para a germinação e as acima de 35 o C são letais para essas sementes. O substrato mais favorável à germinação de sementes de P. volubilis é a vermiculita mícron ou fina.
Plukenetia volubilis is a species native to the Amazonia and has economic potential due to the high contents of polyunsaturated fatty acids and vitamins of the seeds; however, information about production of seedlings in nursery is scarce. Factors that contribute to fast emergence and generation of vigorous seedlings are desirable for plant production in the nursery. Therefore, this study aimed to identify the most favorable substrate and seed position for the production of P. volubilis seedlings. The seeds were sown in the following four positions: hilum facing up, hilum facing down, seed lying on its cotyledon suture, and seed lying flat on one of its cotyledon faces. The substrates were sand, vermiculite and commercial substrate. Treatments were distributed according to a completely randomized design in a 4 × 3 factorial arrangement (seed position and substrate) with three replicates of 25 seeds each. The following variables were evaluated: emergence percentage; first count of seedlings; number, width and length of leaves; plant height; stem diameter; dry matter of shoots and roots. It was concluded that the production of P. volubilis seedlings is not affected by either substrate or seed position at sowing. The substrates most favorable to the quality of P. volubilis seedlings were the commercial substrate and vermiculite, always for the positions of seed lying on its cotyledon suture, with faces parallel to tube walls, and seed lying flat on one of its faces.
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