Joacir Mario Zuffo Júnior

Physiological and sanitary quality of soybean seeds harvested at different periods and submitted to storage1

ABSTRACT RESUMO and harvesting is naturally a crucial one. Soybean seeds reach their maximum dry mass accumulation and maximum physiological quality at the R 7 stage (beginning maturity) (Fehr et al. 1971), time when harvesting should be performed. However, because of the high moisture content of the seeds at that stage, harvesting is performed at the R 8 stage, when 95 % of the pods are mature in color (Diniz et al. 2013a).In many cases, the ideal harvesting time is exceeded due to the vast extension of planted areas and insufficient harvesters, or due to high rainfall rates during the harvesting process. Therefore, seeds may remain exposed in the field for longer periods.Soybean seeds, when stored in the field, are subject to adverse conditions such as climatic 1. Manuscript received in Jun./2017 and accepted for publication in Sep./2017 (http://dx.doi.org/10.1590/1983-40632016v4747576).2. Universidade Estadual do Mato Grosso do Sul, Cassilândia, MS, Brasil. E-mails : alan_zuffo@hotmail.com, steiner@uems.br.3. Universidade do Estado de Mato Grosso, Nova Xavantina, MT, Brasil.

Seed quality response of Urochloa humidicola cv. Llanero to drying surfaces and environments1

1. Manuscript received in Feb./2018 and accepted for publication in Sep./2018 (http://dx.doi.org/10.1590/1983-40632018v4851396). 2. Universidade Federal de Mato Grosso do Sul, Departamento de Agronomia, Chapadão do Sul, MS, Brasil. E-mail/ORCID: alan_zuffo@hotmail.com/0000-0001-9704-5325. 3. Universidade do Estado de Mato Grosso, Departamento de Agronomia, Nova Xavantina, MT, Brasil. E-mail/ORCID: zuffojr@gmail.com/0000-0001-7671-2096. 4. Universidade Federal de Lavras, Departamento de Agricultura, Lavras, MG, Brasil. E-mail/ORCID: everton_zambiazzi@hotmail.com/0000-0002-4598-9129. 5. Universidade Estadual de Mato Grosso do Sul, Departamento de Agronomia, Cassilândia, MS, Brasil. E-mail/ORCID: steiner@uems.br/0000-0001-9091-1737. The drying process and storage may interfere in the quality of creeping signalgrass seeds [Urochloa humidicola (Rendle.) Morrone & Zuloago, syn. Brachiaria humidicola (Rendle.) Schweick.]. This study aimed to evaluate the physical, physiological and sanitary quality of creeping signalgrass cv. Llanero seeds submitted to drying surfaces and environments and stored for two periods (1 and 8 months). The experiment was arranged in a completely randomized design, in a 4 × 2 × 2 + 2 factorial arrangement, with four drying surfaces (soil, asphalt, concrete and ceramic floor), two drying environments (seeds exposed to the sun or shade), two seed storage periods (1 and 8 months) and two additional treatments with drying in paper bags under laboratory conditions (control) and stored for 1 or 8 months, with four replicates. The water content, viability by the tetrazolium test, electrical conductivity, germination rate, germination rate index and seed sanitary quality were measured. Drying at full sun impaired the physiological quality of the seeds due to the high temperatures (46.8-51.0 oC) of the drying surface; however, reduced the incidence of pathogens. The drying of seeds in paper bags under shade results in a higher physiological quality, but the sanitary quality is compromised. However, the pathogens present in the seeds did not inhibit their viability and vigor. The storage for eight months reduces the seed quality.

Análise de crescimento em cultivares de alface nas condições do sul do Piauí

Objetivou-se, com este trabalho, avaliar o crescimento de quatro cultivares de alface, nas condicoes do sul doPiaui, para recomendar os melhores para a regiao. O experimento foi realizado em casa de vegetacao, em blocoscasualizados, com avaliacao em parcelas subdivididas no tempo, avaliadas em seis epocas (20, 24, 28, 32, 36, 40 diasapos a semeadura - DAS) e com os tratamentos correspondentes a quatro cultivares (Americana Rafaela