Abstract: Seed germination percentage, germination index and vigor index of Thladiantha cordifolia(Bl.) Cogn.var.tomentosa A.M.Lu et Z.Y.Zhang rose from zero to maximum value following with the seed developing time from 30 DAA(days after anthesis)to 50 DAA. During this period, the seed MC(moisture content) decreased gradually with different rates. Seed dry weight approached the maximum value and a significant dehydrating stage appeared at 45 DAA shown that they were in a physiological maturing process. When drying the seeds of 40~50 DAA with their moisture content slightly decreased by 2~4% after natural air-drying for one day, the germination capacity of seeds at 40 DAA was improved significantly and that of the seeds at 45~50 DAA had no obvious changes. The germination percentage, germination index and vigor index decreased to various degrees when desiccation kept on. However, germination capacity of 50 DAA seeds appeared no significant change until the moisture content decreased lower than 4%. These results shown that the desiccation-tolerance of seeds were gradually formed and changed during developing process, an order of desiccation-tolerance from maximum to minimum of Thladiantha cordifolia var. tomentosa seed at different developmental stages were 50, 45, 55, 40 and 35 DAA. The Semilethal moisture content could indicate desiccation-sensitivity of Thladiantha cordifolia var. tomentosa seed at various developmental stages.

Key words: Thladiantha cordifolia var. tomentosa, seeds, germination, developmental stages, desiccation-tolerance