A brittle‐stemmed strain of safflower ( Carthamus tinetorius L.) was crossed to 10 genetic types with normal stems. Data showed that the inheritance of brittle stems is determined by a single recessive allele, assigned the symbol br . Brittle stems were not closely linked with the single‐locus recessive characters: closed floret‐A, closed floret‐C, pigmentless, thin hulls, appressed branching, decumbent branches, crinkled foliage, light‐green foliage, and black foliage.
