Specific and robust marker resources available for safflower breeding are scarce. The present research was aimed at developing a collection of genomic microsatellite (SSR) markers and to assess their informativeness. A genomic library enriched for AC-and AG-repeats was constructed from safflower DNA. Around 35% of the 768 clones that were isolated and sequenced contained SSR sequences. From these, 108 unique primer pairs were designed. The majority of the SSRs contained simple di-nucleotide motifs (77 of 108), most of them being perfect repeats (63 of 77). Reference allele length ranged from 95 to 414 bp, averaging 241.2 bp. The 108 SSRs were amplified in a set of ten safflower lines. From 88 SSR markers that amplified successfully, 64 of them detected polymorphism among the ten safflower lines genotyped. The number of alleles per locus ranged from 2 to 8 (mean value of 3.2), whereas heterozygosity ranged from 0.18 to 0.86 (mean value of 0.52). These genomic SSR markers will contribute to advance in safflower molecular breeding.

Safflower (Carthamus tinctorius L.) oil with high oleic acid content ([75%) has a great value for both food and non-food uses. The trait has been reported to be environmentally stable and controlled by recessive alleles at one single gene Ol, even though the influence of modifying genes has been suggested. Additionally, germplasm with higher oleic acid content ([85%) has been reported. The objective of the present research was to study the inheritance of high oleic acid content in genetic sources with both levels of high oleic acid content ([75 and[85%, respectively). A genetic study was conducted by crossing the nuclear male-sterile line CL1 (18% oleic acid) and the high oleic acid lines CR-6 (80%) and CR-9 (87%). The evaluation of the F 1 and F 2 seed generations of the crosses CL1 9 CR-6 and CL1 9 CR-9 indicated that in both cases the high oleic acid trait was controlled by partially recessive alleles at a single locus. The observation of F 2 , F 3 , and F 4 segregants with high oleic acid phenotype but lower oleic acid levels than the parents revealed the presence of modifying genes affecting the trait. Crosses between the two high oleic acid lines produced no transgressive segregation other than that caused by the mentioned modifying genes, suggesting that the high oleic acid lines CR-6 and CR-9share the same alleles at the Ol locus. Differences for oleic acid content between both lines were hypothesized to be produced by the accumulation of genes with a minor effect on the trait.

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Safflower (Carthamus tinctorius L.) possesses the highest amount of linoleic acid among the 10 major vegetable oil crops of the world. Very high linoleic acid content is controlled by recessive alleles at a single locus Li. However, deviated segregations from the expected monogenic inheritance have been observed in crosses involving nuclear malesterile (NMS) lines. The present research was undertaken to study the inheritance of very high linoleic acid content in safflower and its relationship with nuclear male sterility. seed generations were evaluated in a cross between CR-142 (a line with very high linoleic acid content, 88%) and CL1 (an NMS line with wildtype linoleic acid content, 74%). The genetics of linoleic acid content in male-sterile plants was determined by testcrossing with CR-142. The results confirmed monogenic inheritance. The analysis of the F 3 and BC 1 F 2 to CL1 seed generations demonstrated a repulsion-phase linkage between Li and Ms loci, the latter conferring the NMS trait. The recombination rate between Li and Ms was estimated to be 0.09.