INCREASING THE PLOIDY LEVEL IN SPINACH (Spinacia oleracea L.) USING MITOTIC INHIBITORS

Spinach (Spinacia oleracea L.) is a cool season annual leafy vegetable. An important factor in breeding and production of spinach is increment of the leaf size. This is achieved through the traditional method of increasing the ploidy levels. Un-germinated spinach seeds were immersed in the aqueous solutions of colchicine (1, 5 and 10 mg.l-1), trifluralin (2.5, 5 and 7.5 mg.l-1) for 16, 24 and 32 h, and oryzalin (0.01, 0.05 and 0.1 mg.l-1) for 6, 12, and 24 h. The ploidy levels were determined via flow cytometry. Increase in the colchicines concentration decreased the percentage of seed germination. The results showed that despite no significant differences between anti-mitotic chemicals, they increased the ploidy level. However, oryzalin was recommended due to its advantages including low toxicity, low cost and its ability to increase ploidy levels at low concentrations.