Characterization and Inheritance of Long Rosette Safflower

J. Carapetian

Abstract

Eleven selections of late rosette (winter type) safflower were planted both in early fall and early spring and their growth characteristics recorded and compared with 12 selections and varieties of spring type safflower planted in the spring season. Late rosette safflower developed a very hardy and frost resistant seedling in fall planting at about the six-leaf stage with extensive root growth that could stand temperatures of -20 C. Their growth initiation in spring started somewhat earlier than that of spring type safflower and they matured earlier, escaping the late summer shortage of irrigation water.  For the study of the inheritance of the late rosette character, several crosses were made between the spring and winter types and their F1 and F2 progenies were evaluated.  Most of the crosses indicated this character to be a polygenic trait.  However, in one specific cross between LRV55/292 and Frio 3176, all hybrids grew as spring types and in the F2 generation, recorded in several families, they segregated 3:1 (short rosette: long rosette) in greenhouse evaluations, suggesting the long rosette to be a simply inherited recessive Mendelian trait.  Considering the fact that not a single cultivar has yet been bred from the collection of winter type safflower, it appears that the cold resistant character could simply be bred into well-adapted and productive spring cultivars with the possibility of growing safflower as a winter crop in cold regions of the Iranian northwest.

Key words: safflower, cold resistant, rosette, winter type, inheritance.