Effect of the ripening in the cryopreservation of the Nicotiana tabacum L. seeds

Abstract

The main objective of this investigation was to determine the effect of the ripening in the cryopreservation of the Nicotiana tabacum L seeds. cv Sancti Spíritus 96 (SS-96). This study was done between the years 2012 and 2014, at the Tobacco experimental station located in Cabaiguan, Sancti Spiritus. SS-96 seeds were harvest at the 14, 21, 28, 35, 42, 49 and 56 days after the anthesis (DAA), determining the fresh and dry mass to over 1000 seeds, the humidity percentage (fresh mass) and germinating power (GP), as well as evaluate the tolerance of it to desiccation. At the same time, seeds collected every day, were conserved in 5 ºC or liquid nitrogen, and within 30 days, its GP was evaluated and put under accelerated aging and electrolyte leakage tests. During the research it was determined that the physiological ripeness of SS-96 seeds is reached at 29,6 DAA, with a 30,6 % of water and a dry mass of 1000 seeds of 81,2 mg of weight. 35 DAA were established as the optimum momentum for the harvest. The anticipation of the recollection process will end up in a diminishing the desiccation tolerance levels due to the lack of ripeness of seeds; meanwhile a late recollection ends up in lack of potency due to a larger exposure to the environment.