RESUMO O teste de protrusão radicular é um teste de vigor, baseando no princípio de que sementes com alto vigor emitem a raiz primária mais rápido em comparação com as menos vigorosas. A chia é uma planta propagada por sementes, sendo motivo de pesquisa pelos seus benefícios a saúde, mas com poucas informações técnicas sobre a cultura. O objetivo do trabalho foi adequar à metodologia do teste de protrusão radicular para determinação do vigor de lotes de sementes de chia. Utilizou-se cinco lotes de sementes de chia, submetidos à avaliação da qualidade inicial por meio dos testes de germinação e vigor (primeira contagem de germinação, emergência e índice de velocidade de emergência). O teste de protrusão radicular foi realizado nas temperaturas de 20, 25 e 30 ºC, e avaliado a cada duas horas até 42 horas, onde se obteve a estabilidade da protrusão, e sendo utilizado o critério de contagem de 2 mm de raiz primária. O teste de protrusão radicular na temperatura de 20 ºC não distinguiu os lotes semelhantes à emergência. A 25 °C, foi possível classificar os lotes de forma semelhante à emergência após 30 horas. A temperatura de 30 °C foi eficiente na aceleração da protrusão radicular e separação dos lotes de sementes. O teste de protrusão radicular é sensível para detectar diferenças de vigor entre os lotes de sementes de chia, devendo ser conduzido por 30 horas a 25 ºC. | ABSTRACT The root protrusion test is a vigor test based on the principle that seeds with high vigor emit the primary root faster than less vigorous ones. Chia is a plant propagated by seeds and it is studied owing to its health benefits, but there is little technical information known about its culture. The objective of this work was to adapt the methodology of the root protrusion test to determine the vigor of chia seed lots. Five chia seed lots were submitted to an initial quality evaluation using germination and vigor tests (first germination, emergence, and emergence speed index). The root protrusion test was performed at temperatures of 20, 25 and 30 °C and evaluated every 2 h up to 42 h. During the test, protrusion stability was assessed and the criterion of 2 mm primary root count was used. The root protrusion test at 20 °C did not distinguish the lots in the same way as emergence. At 25 °C it was possible to classify lots after 30 h similarly to emergence. At 30 °C, root protrusion and the separation of seed lots was accelerated. Thus, the root protrusion test conducted for 30 h at 25 °C has sufficient sensitivity to detect differences in vigor between chia seed lots.

The root protrusion test is a vigor test based on the principle that seeds with high vigor emit the primary root faster than less vigorous ones. Chia is a plant propagated by seeds and it is studied owing to its health benefits, but there is little technical information known about its culture. The objective of this work was to adapt the methodology of the root protrusion test to determine the vigor of chia seed lots. Five chia seed lots were submitted to an initial quality evaluation using germination and vigor tests (first germination, emergence, and emergence speed index). The root protrusion test was performed at temperatures of 20, 25 and 30 °C and evaluated every 2 h up to 42 h. During the test, protrusion stability was assessed and the criterion of 2 mm primary root count was used. The root protrusion test at 20 °C did not distinguish the lots in the same way as emergence. At 25 °C it was possible to classify lots after 30 h similarly to emergence. At 30 °C, root protrusion and the separation of seed lots was accelerated. Thus, the root protrusion test conducted for 30 h at 25 °C has sufficient sensitivity to detect differences in vigor between chia seed lots.

ABSTRACT: The aim of this study was to evaluate the effect of the sowing periods in production, productivity component and physiological quality of seeds of three soybean cultivars (TMG133RR, P98Y70RR and NS7670RR) in Orthic Quartzarenic Neosoil in the cerrado region. The design used was a randomized block a factorial scheme design with four repetitions, and each plot with useful space consisted of three rows of four meters length, spaced at 0.45 meters. Field evaluations were the final stand, the height of the plants, height of the first pod insertion, the mass of 100 seeds and productivity. Already in the lab seeds were evaluated for germination and vigor (first germination count, emergency, emergence speed index, length and dry mass of the aerial part of the plant and roots, electrical conductivity, accelerated aging and tetrazolium test). It concludes that it is possible to use Orthic Quartzarenic Neosoils, located in the Cerrado region at altitudes higher than 600 m, in years and places with good water distribution in the spring-summer seasons, for grain and soybeans production, but as a first goal, the crop should be sown in the first 20 days of November otherwise it should take place in early December. | RESUMO: O objetivo deste trabalho foi avaliar o efeito de épocas de semeadura na produção, componentes de produtividade e qualidade fisiológica de sementes de três cultivares de soja (TMG133RR, P98Y70RR e NS7670RR) em Neossolo Quartzarênico Órtico na região do cerrado. O delineamento utilizado foi em blocos casualizados num esquema fatorial com quatro repetições, sendo cada parcela com área útil constituída por três linhas com quatro metros de comprimento, no espaçamento de 0,45 m. As avaliações no campo foram estande final, altura de plantas, altura de inserção da primeira vagem, massa de 100 sementes e produtividade. No laboratório, as sementes foram avaliadas quanto à porcentagem de germinação e vigor (primeira contagem de germinação, emergência, índice de velocidade de emergência, comprimento e massa seca de parte aérea e raiz, condutividade elétrica, envelhecimento acelerado e tetrazólio). Conclui-se que é possível a utilização de Neossolos Quartzarênicos Órticos, localizados em região de cerrado com altitude superior a 600 m, em anos e locais com boa distribuição hídrica na primavera-verão, para produção de grãos e sementes de soja, sendo que no primeiro objetivo, a cultura deve ser semeada nos primeiros 20 dias de novembro e no segundo caso, essa deve ocorrer no inicio de dezembro.

The aim of this study was to evaluate the effect of the sowing periods in production , productivity component and physiological quality of seeds of three soybean cultivars (TMG133RR, P98Y70RR and NS7670RR) in Orthic Quartzarenic Neosoil in the cerrado region. The design used was a randomized block a factorial scheme design with four repetitions, and each plot with useful space consisted of three rows of four meters length, spaced at 0.45 meters. Field evaluations were the final stand, the height of the plants, height of the first pod insertion, the mass of 100 seeds and productivity. Already in the lab seeds were evaluated for germination and vigor (first germination count, emergency, emergence speed index, length and dry mass of the aerial part of the plant and roots, electrical conductivity, accelerated aging and tetrazolium test). It concludes that it is possible to use Orthic Quartzarenic Neosoils , located in the Cerrado region at altitudes higher than 600 m, in years and places with good water distribution in the spring - summer seasons, for grain and soybeans production, but as a first goal, the crop should be sown in the first 20 days of November otherwise it should take place in early December.

RESUMO: Objetivou-se nesta pesquisa avaliar o efeito de diferentes herbicidas aplicados como dessecantes em pré-colheita sobre a qualidade fisiológica e sanitária de sementes de feijão azuki (Vigna angularis Willd.) e armazenadas. Foi adotado o delineamento experimental em blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. Testaram-se nas parcelas cinco princípios ativos de herbicidas: paraquat (400 g i.a ha-1), glufosinato de amônio (400 g i.a ha-1), glyphosate (720 g e.a ha-1), flumioxazin (30 g i.a ha-1) e uma testemunha sem aplicação de herbicida; e nas subparcelas as duas épocas de armazenamento das sementes (colheita e 6 meses após a colheita). A aplicação dos dessecantes ocorreu na maturidade fisiológica do feijoeiro. Foi avaliado a qualidade fisiológica e sanitária das sementes através de teste de vigor e sanidade de sementes. O uso do herbicida glyphosate promoveu maior incidência de plântulas anormais e redução do tamanho e massa das plântulas. Os herbicidas paraquat e flumioxazin mantiveram a qualidade fisiológica das sementes e promoveram menor infestação de patógenos aos seis meses após a colheita. O armazenamento afetou a qualidade fisiológica de sementes de feijão azuki. | ABSTRACT: The objective of this research was to evaluate the effects of using different herbicides as desiccants in pre-harvest and the effects of storage on the physiological and sanitary quality of azuki bean seeds (Vigna angularis Willd). The experiment was arranged in a randomized complete block design in a split plot scheme, with four replications. Four herbicides were tested: paraquat (400 g a.i. ha-1), glufosinate ammonium (400 g a.i. ha-1), glyphosate (720 g a.i. ha-1), flumioxazin (30 g a.i. ha-1) and a control without herbicide application. In the subplots seed quality was tested in two evaluation periods: at harvest and six months after harvest. Desiccant was applied when the azuki beans were physiologically mature. We assessed the physiological and sanitary quality of the seeds using a vigour and seed health test. The use of glyphosate resulted in a higher incidence of abnormal seedlings and reduced size and weight of the seedlings. With paraquat and flumioxazin the physiological quality was maintained and there was reduced pathogen infestation in the seeds six months after harvest. Storage affected the physiological quality of the azuki bean seeds.

The objective of this research was to evaluate the effects of using different herbicides as desiccants in pre - harvest and the effects of storage on the physiological and sanitary quality of azuki bean seeds ( Vigna angularis Willd). The experiment was arranged in a randomized complete block design in a split plot scheme, with four replications. Four herbicides were tested: paraquat (400 g a.i. ha - 1 ), glufosinate ammonium (400 g a.i. ha - 1 ), glyphosate (720 g a.i. ha - 1 ), flumioxazin (30 g a.i. ha - 1 ) and a control without herbicide application. In the subplots seed quality was tested in two evaluation periods: at harvest and six months after harvest. Desiccant was applied when the azuki beans were physiologically mature. We assessed the physiological and sanitary quality of the seeds using a vigour and seed health test. The use of glyphosate resulted in a higher incidence of abnormal seedlings and reduced size and weight of the seedlings. With paraquat and flumioxazin the physiological quality was maintained and there was reduced pathogen infestation in the seeds six months after harvest. Storage affected the physiological quality of the azuki bean seeds.

ABSTRACT Sweet corn is an important crop because of its seeds with high total sugar and low starch contents. As common corn, this group requires an adequate amount of nitrogen to reach high yields. However, the studies on nitrogen and sweet corn are performed for ear yield instead of seed yield. As seeds are the main propagation method for this species, we proposed to evaluate the effects of nitrogen rates as side-dressing at different plant stages of a sweet corn seed production. Sweet corn seeds (variety BR 400) were sown in Latosol (Oxisol), and a 3×2+1 factorial scheme was designed with three nitrogen rates (40, 80, and 120 kg ha-1) at two plant stages (V6 and R1) plus the control (no nitrogen side-dressing). The evaluated variables were seed yield, protein content, P and Zn contents, germination, and vigor rates. We concluded that nitrogen applied at a rate of 120 kg ha-1 at V6 increases seed yield and maintains unaltered the protein content in seeds of sweet corn (BR 400 variety). Neither germination nor seed vigor increases when nitrogen rates are increased or administered at different stages of plant development. We also noted a slight decrease in P content or an increase in Zn content of seeds at low nitrogen rates; however, they are insufficient to promote changes in the physiological potential of sweet corn seeds. | RESUMO O milho doce é uma cultura importante por causa do seu tipo de sementes com índice elevado dos açúcares totais e baixo índice do amido. Como o milho comum, este necessita de quantidade adequada de nitrogênio para atingir altas produtividades, no entanto, os estudos que envolvem nitrogênio e milho doce são realizados para o rendimento das espigas e não para a produção de sementes. Como a semente é o principal método de propagação dessa espécie, foi avaliado os efeitos das doses de nitrogênio em cobertura em diferentes estádios fenológicos para produção e potencial fisiológico de sementes de milho doce. As sementes de milho doce (variedade BR 400) foram semeadas em Latossolo e um esquema fatorial de tratamento 3 × 2 + 1 foi instalado com três doses de nitrogênio 40, 80 e 120 kg ha-1 e dois estádios fenológicos (V6 e R1) mais o controle (sem nitrogênio em cobertura). Foram avaliadas a produtividade de sementes, teores de proteína, P e Zn, germinação e vigor. Como conclusão, o nitrogênio fornecido em V6 a 120 kg ha-1 aumenta a produtividade de sementes e mantém os teores de proteína inalterados. A germinação da semente e o vigor não aumentam quando as taxas de nitrogênio são acrescidas ou fornecidas em diferentes estádios fenológicos. Diminuição ligeira do teor de P ou o aumento do teor de Zn nas sementes são observados a uma dose baixa de nitrogênio entretanto não suficientes para promover alterações no potencial fisiológico das sementes do milho doce.

Sweet corn is an important crop because of its seeds with high total sugar and low starch contents. As common corn, this group requires an adequate amount of nitrogen to reach high yields. However, the studies on nitrogen and sweet corn are performed for ear yield instead of seed yield. As seeds are the main propagation method for this species, we proposed to evaluate the effects of nitrogen rates as side-dressing at different plant stages of a sweet corn seed production. Sweet corn seeds (variety BR 400) were sown in Latosol (Oxisol), and a 3×2+1 factorial scheme was designed with three nitrogen rates (40, 80, and 120 kg ha-1) at two plant stages (V6 and R1) plus the control (no nitrogen side-dressing). The evaluated variables were seed yield, protein content, P and Zn contents, germination, and vigor rates. We concluded that nitrogen applied at a rate of 120 kg ha-1 at V6 increases seed yield and maintains unaltered the protein content in seeds of sweet corn (BR 400 variety). Neither germination nor seed vigor increases when nitrogen rates are increased or administered at different stages of plant development. We also noted a slight decrease in P content or an increase in Zn content of seeds at low nitrogen rates; however, they are insufficient to promote changes in the physiological potential of sweet corn seeds.

ABSTRACT The accelerated aging test consists of evaluating the vigor of the seeds under conditions of high temperature and humidity, with the purpose of identifying the physiological quality of lots with similar germination. The objective of this study was to evaluate the efficiency of the accelerated aging test for classifying seed lots of P. moniliformis at different levels of vigor. Initially, the seed lots were assessed by means of seedling emergence, life velocity index, shoot length and root length, total dry mass of seedlings and determination of water content, before and after each period of aging. The experimental design for the whole world was based on a 3 × 4 factorial scheme (three seed lots and four periods of 24, 48, 72 and 96 h duration), with separate evaluations at temperatures of 38 °C and 41 °C. The accelerated aging test conducted at a temperature of 41 °C for 24 h was a more suitable combination for separating batches of P. moniliformis according to different levels of vigour, and made it possible to obtain results similar to the classification of lots in relation to the initial quality. | RESUMO O teste de envelhecimento acelerado consiste em avaliar o vigor das sementes em condições de elevada temperatura e umidade, com a finalidade de identificar diferenças na qualidade fisiológica de lotes com germinação semelhante. Dessa forma, objetivou-se avaliar a eficiência do teste de envelhecimento acelerado para classificar os lotes de sementes de P. moniliformis em diferentes níveis de vigor. Inicialmente os lotes de sementes foram avaliados por meio da emergência de plântulas, índice de velocidade de emergência, comprimento da parte aérea e da raiz, além da massa seca total de plântulas, além da determinação do grau de umidade, antes e após cada período de envelhecimento das sementes. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 3 x 4 (três lotes de sementes e quatro períodos de 24, 48, 72 e 96 horas), e avaliado separadamente nas temperaturas de 38 e 41 °C. O teste de envelhecimento acelerado conduzido sob a temperatura de 41 °C durante 24 horas é a combinação mais adequada para separar os lotes de P. moniliformis em diferentes níveis de vigor, pois possibilitou a obtenção de resultados semelhantes à classificação dos lotes em relação à qualidade inicial.

The accelerated aging test consists of evaluating the vigor of the seeds under conditions of high temperature and humidity, with the purpose of identifying the physiological quality of lots with similar germination. The objective of this study was to evaluate the efficiency of the accelerated aging test for classifying seed lots of P. moniliformis at different levels of vigor. Initially, the seed lots were assessed by means of seedling emergence, life velocity index, shoot length and root length, total dry mass of seedlings and determination of water content, before and after each period of aging. The experimental design for the whole world was based on a 3 × 4 factorial scheme (three seed lots and four periods of 24, 48, 72 and 96 h duration), with separate evaluations at temperatures of 38 °C and 41 °C. The accelerated aging test conducted at a temperature of 41 °C for 24 h was a more suitable combination for separating batches of P. moniliformis according to different levels of vigour, and made it possible to obtain results similar to the classification of lots in relation to the initial quality.