Analysis of dormancy and physiological quality of Stylosanthes spp. stored in FGB-UEFS

Resumo

Knowledge on the viability of the seeds is important in the management of the Germplasm Bank, as it allows monitoring the longevity and the need for regeneration of the accessions. The objective was to validate the efficiency of the Gomez-Campo methodology for seed conservation by evaluating physical dormancy and physiological quality of 11 Stylosanthes spp. accessions stored between seven and 13 years in the Forage Germplasm Bank of the State University of Feira de Santana (FGB-UEFS). One-hundred seed were used to determine moisture degree (%) and the viability with the descriptors: percentage of germination (G), germination speed index (GSI), synchronicity (Z) and average germination time (AGT). Sowing was done in plates moistened with water, arranged under controlled conditions (BOD chambers: at 20/30 °C and 12 hours/light) and in a completely randomized design in a 2 x 11 factorial scheme (scarified/non-scarified seeds and 11 accessions). After 14 days, it was observed that most of the accessesion presented high G (greater than 70%), GSI less than 2 seeds.day^-1, Z with a mean value of 0,52 and AGT with a mean value of 2 days, characterizing a synchronous and rapid event. Thus, the methodology used in storage is efficient for the conservation of Stylosanthes seeds in the medium term.