The effect of cryopreservation in liquid nitrogen on the viability of flax seeds

Abstract

Background. A promising technique for preserving plant genetic resources is cryopreservation of seeds in liquid nitrogen at –196°C. The lack of information on cryopreservation of flax seeds and on the effect of liquid nitrogen on their viability makes this work relevant for the conservation of valuable flax germplasm.Materials and methods. Seeds of the fiber flax cultivar ‘Orshansky 2’ were used in the experiment. The experiment was carried out in 2 replications; each of them included 6 options. In options 1 and 2, the seeds were stored in paper bags at room temperature (1 – control, seeds without treatment; 2 – treated with a biodegradable polymer of 3-hydroxybutyric acid [P(3GB)]). In options 3, 4, 5 and 6, the seeds were stored in liquid nitrogen without treatment and with P(3GB) treatment (in 3 and 4 in gauze packaging, and in 5 and 6 in laminated foil bags).Results. Laboratory-based germination energy and viability of control seeds were the same in all options of the experiment (99%), and field viability averaged 83%. The lowest germination energy, laboratory-based and field germination capacity were observed after storage in laminated bags, without P(3HB) processing: option 5. stage II (79%); option 5, stage III (74%), and with P(3HB): processing: option 6, stage II (78%); option 6, stage III (82%). A two-factor analysis of variance showed that liquid nitrogen had significant effect on laboratory germination energy, field germination capacity, laboratory germination energy and capacity after 6 months of storage at room temperature: the effect size was 42, 11, 31, and 24%, respectively, while treatment with P(3HB) had no significant effect on any of the options of the experiment with its application.Conclusion. Flax seeds tolerated direct immersion in liquid nitrogen (t = –196°C) best of all in gauze packaging. The biodegradable polymer P(3HB) did not produce a significant effect on seed viability in any option.