Safflower (Carthamus tinctorius) is an annual, rustic plant that has multiple uses. Seed laboratory analysis showed discrepancies in germination depending on the substrate used in a given lot. Therefore, studies are needed to determine the best substrate and the time required to perform the first and final count of the safflower seed germination test. Five lots were used, which were characterized by moisture degree and thousand seed weight. These lots were evaluated on four substrates (between paper, on paper, paper roll, and between sand). The five lots and four substrates were distributed in a 5x4 factorial scheme in a randomized block design with four replicates of 25 seeds. The influence of the factors was evaluated by daily germination count until stabilization, determining the percentage of normal and abnormal seedlings and dead seeds; germination speed index; initial, mean, and final germination time; synchrony and relative frequency; and the date of the first and final germination count. After obtaining the data, analysis of variance was performed. When there was a significant effect, the means were compared using the Tukey test at 5% and 1% probability. Therefore, it is recommended that the safflower seed germination test be conducted on the substrate between paper, with the first and final count being performed at 3 rd and 8 th days, respectively.

In evaluating the quality of seed lots, vigor tests are complementary to the germination test, identifying differences in their degree of deterioration. However, for safflower seeds (Carthamus tinctorius L.) there is little information regarding these tests. Thus, the objective was to adapt the cold test methodology to evaluate the vigor of safflower seeds. For that, twelve lots were initially characterized by moisture content, mass of one thousand seeds, germination and seedling emergence in the field. After characterization the samples were conditioned in transparent plastic boxes on paper moistened with water and kept at 10 °C for the periods of 0, 3, 5 and 7 days. After the conditioning periods the samples were transferred to a germination chamber at 25 ºC, with evaluation of normal seedlings on the 3rd day. The obtained data was subjected to variation analysis and when significant, compared by the Scott-Knott method at 5% probability. To verify the efficiency of the methodologies, the principal component analysis was performed. The cold testing at 10 °C for 7 days is recommended for evaluating the physiological quality of safflower seeds.

In assessing the quality of seed lots, the vigor tests are complementary to the germination test and they identify differences in the degree of deterioration of the lots. For safflower, there is little information regarding these tests. In this way, the intention of this study was to adapt the accelerated aging test methodology to assess the physiological potential of safflower seeds (Carthamus tinctorius). For this purpose, 12 seed lots were evaluated for thousand-seed weight, germination, first germination count, seedling emergence test (emergence percentage, emergence speed index, relative emergence frequency and the initial, final and mean times) and accelerated aging. For the accelerated aging test, the traditional and saline methods were used. For this, the samples were conditioned in periods of 0, 8, 16, 24, 32 and 48 hours at 42 °C. Afterwards, they were submitted to the germination test, with evaluation of normal seedlings on the 3rd day. The 12 lots were evaluated within each period, in independent experiments. The data were submitted to analysis of variance and the means were compared using the Scott-Knott clustering method at 5% probability. In the traditional accelerated aging test the periods of 16, 24, 32 and 48 hours were more efficient in differentiating the lots in vigor levels, as they stratified the lots in three classes and the time of 8 hour classified the lots in two levels of vigor. In the accelerated saline aging method the time 32 hours were more efficient since it ranked seed lots at three levels of vigor and the periods of 8, 16 and 24 hour stratified the lots in two levels. In results obtained by the principal component analysis it was verified. The variables traditional accelerated aging for 24 and 32 hours correlated with emergence in the field. Therefore, the traditional accelerated aging test at 42 °C for 24 hours are promising for evaluating the physiological quality of safflower seeds.

Todo o conteúdo deste livro está licenciado sob uma Licença de Atribuição Creative Commons. Atribuição 4.0 Internacional (CC BY 4.0). O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.

Todo o conteúdo deste livro está licenciado sob uma Licença de Atribuição Creative Commons. Atribuição 4.0 Internacional (CC BY 4.0). O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos autores. Permitido o download da obra e o compartilhamento desde que sejam atribuídos créditos aos autores, mas sem a possibilidade de alterá-la de nenhuma forma ou utilizá-la para fins comerciais.