Effects of bracts on seed germination of Ceratoides arborescens in sodium chloride

In this study,two treatments(with and without bracts) were evaluated on seeds treated with different NaCl solutions.Seeds with bracts had higher germination percentage,germination index,and vigour index than seeds without bracts.The germination percentage of bracteolate seeds was significantly(P0.05) higher than that of seeds without bracts at salinities of 70,140,210,280,and 420 mmol/L,with germination percentages of 90.00%,89.00%,79.75%,69.25%,53.75%(bracts) and 78.50%,81.50%,74.00%,62.25%,39.25%(no bracts),respectively.The rate of water uptake of seeds with bracts was higher than that of those without bracts in both distilled water and NaCl solutions.After treating seeds with or without bracts in 490 mmol/L NaCl solution for 1,3,or 7 d,the Na+ contents significantly increased in the bracts.The bracts absorbed Na+ and reduced the damage to the embryo.Therefore the presence of bracts is of great importance when Ceratoides arborescens is planted in saline desert environments.