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.

Multivariate techniques allow to understand the structural dependence contained in the variables, as well as to characterize groups of seed lots according to specific standards. Thus, this study analyzes the efficiency of multivariate exploratory techniques in discriminating forage pea seed lots as a function of the physiological potential of seeds. We evaluated ten seed lots of forage pea in a completely randomized design, considering the following variables: thousand seed weight, germination, first germination count, electrical conductivity, and accelerated aging. Moreover, seedling emergence, first count of seedlings in the field, and seedling emergence speed index in the field were added to randomized blocks with four replications per lot. Initially, the data obtained in each test were analyzed separately by means of analysis of variance, and the means of the treatments were compared by the Scott Knott test at 5% probability. Exploratory multivariate statistical techniques were applied by means of Cluster Analysis and Principal Components Analysis to discriminate seed lots with better physiological quality and to characterize the variables responsible for the differentiation between them. Multivariate analysis of principal components is efficient in discriminating vigor and seed germination tests in Pisum sativum subsp. Arvense, which help in identifying lots of superior performance in the field.

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.

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