Morphological, physiological, cytological characteristics and agricultural potential of colchicine induced autotetraploid plants in safflower

Safflower (Carthamus tinctorius L.) is one of the important oilseed and bio-energy crops. All safflower cultivars in world have diploid genomes (2n= 2x= 24). In this research, autotetraploidy induction was performed by colchicine treatments to emerging shoot tips at cotyledonary stage. As a result flow cytometric analyses C2 progenies, autotetraploids (4x= 48) had DNA content 4.88 pg 2C-1, while diploids (2x= 24) 2.29 2C-1. The generation exhibited bigger stomata size (33.40 μm 46.90 length) higher chloroplast number (9.5 17.2 guard cells), but less stomatal density (17.98% 16.67% index) compared their counterparts. However, reduced pollen viability from 80.24% 16.20%, seed set rate 35.06% 7.01% per capitula. result, autotetraploid plants were able produce very few seeds despite high unit weight heads. While oil large-seeded significantly lower, two-fold, (26.37% 13.23% whole seeds) than small-seeded diploids, fatty acid composition not influenced autopolyploidization.