Evaluation of Safflower Germplasm for Ornamental Use

Abstract

Safflower (Carthamus tinctorius L., Asteraceae), is an annual or winter annual herbaceous plant that is adapted for growth in hot and dry environments. Plants often have many spines on leaves and bracts, although plants with few spines exist. Young plants form rosettes that tolerate temperatures as low as –7°C, but are unable to compete well with weeds. Stem elongation in spring-planted safflower begins approximately one month after emergence. After stem elongation the plants are very susceptible to frost injury (Helm et al. 1991). Florets form a capitulum at the end of each stem, usually displaying hues of yellow, orange, red, and rarely white, which darken when dry (Li and Mündel 1996). Safflower is mostly selfpollinating in the absence of pollinators (Knowles 1969). The Western Regional Plant Introduction Station (WRPIS) is a part of the United States National Plant Germplasm System (NPGS) and maintains the US safflower collection which includes more than 2,300 accessions collected from over 50 countries. Descriptors for the crop include branching pattern, flower color, spininess, head size, plant height, date of flowering, growth habit, iodine number, lysine content, and oil content. Many of the accessions have been evaluated for one or more descriptors and the data have been