Effects of Drought Stress on Oil Characteristics of Carthamus Species

Safflower (Carthamus tinctorius L.) is one of the oldest domesticated crops, mainly grown as oilseed in the arid and semi arid regions of the world. Cross-ability of Carthamus species has made wild safflower species a suitable source for transferring drought tolerant genes to cultivated species. This study was conducted to investigate seed yield per plant, oil content and fatty acid composition of some Carthamus species and to identify the effects of drought stress on these measured traits. In this regard, 27 genotypes from C. tinctorius, C. palaestinus, C. oxyacanthus, C. lanatus and C. glaucus were planted in the field under normal and drought-stress conditions for two years. Results showed that some studied species differed in oil content, seed yield per plant and fatty acid profiles. As an example, the highest seed oil content (32%) was found in genotype number 22 from C. palaestinus, and the lowest (18%) was obtained for the genotype number 11 from C. lanatus. For all the species, oil content was not affected by moisture stress and did not change over different environments. Similar and stable responses of various Carthamus species for fatty acid composition indicated that hybridization between these species for genetic improvement of drought tolerance may have no adverse effects on oil quality. Considerable diversity within species for all measured traits, similarity in fatty acid profiles and almost the same pattern of changes under drought stress showed that the wild species especially the crossable ones, are good candidates to be used in breeding of cultivated safflower.