Substrates and duration for conducting the safflower seed germination test

Abstract

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.