Pregerminative treatments in Tillandsia ionantha seeds to obtain seedlings under in vitro culture
native, conservation, bromeliad.
Objective: To search for an in vitro strategy to favor both germination and a greater number of seedlings in Tillandsia ionantha; also, to promote the development of future research on this species.
Design/methodology/approach: Factor one: lighting conditions (light-dark), factor two: 13 preconditioning treatments, which included storage at room temperature and in refrigeration at 10° C, soaking (12 and 24 hours), with hydrogen peroxide (10 and 20 %), potassium nitrate (0.2 and 0.4 %), gibberellins (50 and 150 ml.l-1), three alternate incubation temperatures (28, 32 and 36 °C). They were sown in MS medium (Murashige and Skoog, 1962) at 25 %, adding 20 g.l-1 of sugar, 2 g.l-1 of activated carbon, and 5 .5 g.l-1 of agar. A flask with three seeds which coma removed was established as an experimental unit; 15 repetitions were established and placed in the incubation room at 24 °C with a photoperiod of 16:8. The germination process was recorded, and the seedlings were extracted two months after their establishment.
Results: The treatment that resulted in the highest number of seeds that initiated the germination process and the highest number of plants was when the seeds were kept at room temperature. The highest contamination was observed in the treatment exposed to 32 °C. It was observed that 80% of the experimental units showed signs of imbibition within a few days, although the vast majority did not complete the process and the maximum yield was on average 1.4 seedlings.
Conclusions: The best treatment is to use seeds stored at room temperature and if storage is necessary, to soak them for 12 h.