ResumoO presente trabalho foi conduzido com o objetivo de avaliar diferentes volumes de água destilada no substrato e temperaturas na germinação e no vigor de sementes de melão, variedade pepino. O experimento foi conduzido no Laboratório de Análise de Sementes da Unimontes, no período de fevereiro a abril de 2012. A semeadura foi realizada em rolos de papel do tipo "germitest", umedecidos com volumes (mL) de água destilada equivalentes a 1,0; 1,5; 2,0; 2,5 e 3,0 vezes o peso do substrato seco, sem adição posterior de água, com três folhas por rolo. Os rolos foram mantidos em germinadores previamente regulados nas temperaturas constantes de 25 e 30°C e alternada de 20-30ºC. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 5 x 3 (volumes de água destilada e temperaturas), com quatro repetições de 50 sementes. Avaliou-se a porcentagem de germinação, índice de velocidade de germinação, comprimento de raiz e parte aérea, massa fresca e seca de plântulas. Diante dos resultados, conclui-se que as combinações de volume de água destilada no substrato e a temperatura de exposição que proporcionam melhores respostas na germinação e no vigor das sementes de melão, variedade pepino, são de 1,0 vez o peso do substrato seco na temperatura de 30ºC e 3,0 vezes o peso do substrato seco a 25 e 20-30ºC. Dentre as temperaturas estudadas, a temperatura de 30ºC promove melhores respostas em todas as variáveis analisadas, sendo recomendada como temperatura adicional para avaliação da qualidade fisiológica de sementes de melão. Palavras-chave: Cucumis melo L., análise de sementes, teste de germinação AbstractThis study was conducted to evaluate different volumes of distilled water and substrate temperatures on germination and vigor of melon, cucumber variety. The experiment was conducted at the Laboratory of Seed Analysis Unimontes in the period february to april 2012. Sowing was done on paper rolls like "germitest" moistened with volumes (mL) of distilled water equivalent to 1.0; 1.5; 2.0; 2.5 and 3.0 times the weight of dry substrate without further addition of water, with three sheets per roll. The rolls were kept in germination preset constant temperatures of 25 to 30°C and 20-30°C alternate. The experimental design was completely randomized in a factorial 5 x 3 (distilled water volume an temperatures), with four replicates of 50 seeds. We evaluated the germination percentage, germination velocity index, root

ResumoObjetivou-se com esse trabalho avaliar as diferentes épocas de colheita sobre a qualidade fisiológica de sementes de crambe, cultivar FMS Brilhante. O experimento foi instalado na Área Experimental da Universidade Estadual de Montes Claros -UNIMONTES, em Janaúba, MG, em 03 de setembro de 2011. A primeira colheita dos racemos foi realizada aos 14 dias após a floração, quando aproximadamente 50% das plantas apresentavam floração plena. As demais colheitas foram realizadas em intervalos de seis em seis dias, perfazendo um total de cinco colheitas. Foi determinado também o acúmulo de unidades térmicas, em graus dia, durante os intervalos de tempo. Os racemos colhidos foram levados ao Laboratório de Análise de Sementes da UNIMONTES, onde permaneceram sob condições ambientais até a realização das análises. As sementes foram avaliadas quanto ao teor de água, à germinação e ao vigor (matéria seca de sementes, massa de mil sementes, emergência de plântulas e índice de velocidade de emergência). O delineamento experimental utilizado foi inteiramente casualizado, com cinco épocas de colheita, que consistiram nos tratamentos, e quatro repetições. As sementes de crambe apresentam dormência pós-colheita. O máximo acúmulo de matéria seca (maturidade fisiológica) ocorreu aos 26 dias após a floração. Conclui-se que a melhor época para realizar a colheita de sementes de crambe, cultivar FMS Brilhante, com maior qualidade fisiológica (máximo de germinação e vigor) ocorre no período de 14 a 26 dias após a floração, que representa uma soma térmica de 1111,1 a 1302,15 graus dia. Palavras-chave: Crambe Abssinica Hochst, germinação, maturidade fisiológica, vigor AbstractThe objective of this study was to evaluate different harvest seasons on the seed quality of crambe, cultivar FMS Brilhante. The experiment was carried out at Experimental area of the Montes Claros State University -UNIMONTES in Janaúba-MG, on September 3, 2011. The first raceme harvest was performed 14 days after flowering, when approximately 50% of the plants showed full flowering. The other harvests were performed every six days, making a total of five harvests. Accumulation of thermal units in degrees day during time intervals was also determined. The collected racemes were taken to the Laboratory of Seed Analysis at UNIMONTES, when they remained under ambient conditions until beginning the analyses. Seeds were evaluated as for water content, germination and vigor (dry

Accelerated aging test in seeds of crambe (Crambe abyssinica Hochst), cultivar FMS BrilhanteThe use of high physiological quality seeds is essential in the establishment of any crop. Germination and vigor tests are required for seed quality control. The objective of this study was to evaluate the efficiency of the accelerated aging test in determining the vigor of crambe seeds. The initial quality of five lots of crambe seeds, cultivar FMS Brilhante, was assessed by determining the water content, germination, germination first count, seedling emergence index and emergence rate. For the accelerated aging test, the seeds were subjected to temperatures of 41 and 43 °C in a BOD chamber for 48, 72 and 96 hours. At the end of each aging period, the seeds were put to germinate according to the methodology for the germination test. The experiment was arranged in a completely randomized design with four replications per lot. The accelerated aging test under the condition of 41 °C for 72 h provided the greatest vigor discrimination between the lots of crambe seeds, cultivar FMS Brilhante. Key words:Crambe abyssinica Hochst, oilseed, physiological quality, force.

Information about the effect of herbicides on cowpea seed quality is scarce. The objective of this work was to evaluate the effect of using chemical desiccants at pre-harvest on the anticipation of harvest and physiological quality of cowpea seeds of the cultivar BRS-Tumucumaque, before and after storage. Two experiments were conducted: experiment 1 was conducted under a randomized block design, with four replications; the treatments consisted of seven herbicides (carfentrazone-ethyl, saflufenacil, glyphosate, paraquat, flumioxazin, glufosinate-ammonium, and diquat) and a control treatment; anticipation of harvest, and seed water content, germination, and vigor were evaluated. The seeds were stored for six months in controlled environment and not-controlled environment rooms and evaluated for water content, germination, and vigor in Experiment 2, which was conducted in a 7^2+1 factorial arrangement, with four replications; the first factor consisted of the seven herbicides, the second factor was the two storage environments, plus a control treatment. The results showed 3 to 9 days of anticipation of harvest relative to the control. The glufosinate -ammonium herbicide negatively affected seed germination and vigor. The glyphosate herbicide decreased seed germination and vigor after storage. The physiological quality of cowpea seeds at the post -harvest period and after six months of storage was not affected by the carfentrazone-ethyl and flumioxazin herbicides. Paraquat and diquat were the most efficient herbicides for the anticipation of harvest (nine days). Glyphosate and glufosinate -ammonium were the most harmful herbicides to seed physiological quality. The controlled environment room was the most adequate environment for seed conservation.

O objetivo do trabalho foi caracterizar a morfologia de frutos, sementes e plântulas, assim como determinar o substrato adequado para germinação e desenvolvimento inicial de plântulas de vinagreira. No estudo morfológico de frutos, foram observadas características internas e externas referentes à coloração, consistência, forma, número de sementes e deiscência. Para descrição das sementes, analisou-se a coloração, forma, textura e consistência dos tegumentos. Foram conduzidos testes de germinação nos substratos rolo de papel “germitest”, entre e sobre papel mata-borrão e entre areia, visando à caracterização das plântulas e a avaliação da qualidade fisiológica das sementes, sendo avaliadas quanto à germinação e vigor (índice de velocidade de germinação, comprimento de plântulas, massa fresca e seca de plântulas). O estudo morfológico das estruturas de vinagreira é importante para o conhecimento da espécie, favorecendo o desenvolvimento de técnicas adequadas de manejo. A germinação é epígea fanerocotiledonar, iniciando a partir do segundo dia após semeadura. Recomenda-se utilizar o substrato rolo de papel germistest para o teste de germinação em sementes de vinagreira com contagens aos sete (primeira contagem) e 14 dias (germinação) após a semeadura.

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Seed drying has many advantages, but it can cause irreversible damages, compromising the physiological quality of seeds, especially when they present high water contents. The objective of this work was to evaluate the effect of drying conditions (inside and outside the pod) on the physiological quality of cowpea seeds of the cultivar BRS-Tumucumaque before and after storage. A completely randomized experimental design with four replications was used, in a split-plot arrangement. The plots consisted of combinations of harvest seasons (1, 2, 3, 4, and 5) and artificial seed drying conditions (inside and outside the pod); and the subplots consisted of storage times (0 and 6 months). The seed water contents were determined and the seeds were evaluated for germination, first germination count, emergence, emergence index, accelerated aging, and electrical conductivity. Higher physiological quality was found for dried seeds inside the pods, which was more evident in seasons 1 and 2, in both storage times. In the other seasons, the drying conditions had no effect on seed germination and vigor at the beginning of storage. The dried seeds inside the pods showed greater vigor after six months of storage. Drying seeds inside the pods favors the maintenance of physiological quality and allows artificial drying of cowpea seeds of the cultivar BRS-Tumucumaque with water content of 47%. Artificial drying of seeds with water contents higher than 32.5% is not recommended for the condition outside the pod. The seed physiological potential decreases after six months of storage, regardless of the drying condition.

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