Vigor and physiological properties of ultra-drying seeds of Larix principis-rupprechtii Mayr. and L. kaempferi(Lamb.)

Using ultra-drying over silica gel(at room temperature) and accelerated aging(50 ℃, 30 d) methods, we studied the storage behavior of Larix principis-rupprechtii Mayr. and L. kaempferi(Lamb.) Carr. seeds. Seed germination percentage(GP), germination energy(GE), germination index(GI), vigor index(VI), relative conductivity(RC), dehydrogenase activity(DA) and isocitrate lyase activity(ICL) after ultra-drying(pre-aging) and accelerated aging were investigated. The results showed that higher GE, GP, GI, VI, DA and ICL were found in the seeds with moisture content(MC) of 50-28 g/kg for L. principis-rupprechtii and 48-28 g/kg for L. kaempferi before and after aging, indicating the feasibility of ultra-drying storage for seeds of these two species. Furthermore, all indices of seeds with MC of 28 g/kg were best for both species, indicating their better anti-aging ability than seeds with other MCs. The results indicate that 28 g/kg of MC was optimum for the ultra-dying storage of L. principis-rupprechtii and L. kaempfer seeds.