Composition And Application Of Seed Coating Formulas For Platycladus Orientalis

Seed coating is a mechanically way developed for the growth of seeds and seedlings,so as to improve seeds germination,seedlings vigor and stress resistance.In the vast areas of northern China,Platycladus orientalis is an significant tree species with the strong ecological adaptability and high economic value.In the experiment,the CS-nano Ti O2,GA3,Ge-132 and SA were screened with the seeds of P.orientalis to get the the effects of seeds germination and seedlings growth with the individual components and compound ratios.The work investigated the effect of treatments on P.orientalis,seedlings morphological and physiological index of P.orientalis to select the best seed coating besides the PEG simulated drought conditions to verify the practicability of seed coating agents,so as to provide theoretical basis for the scientific application in P.orientalis.?1?The compound of film former formula was 0.2%CS+0.06 g nano-Ti O₂,which significantly improved the germination rate,germination index and vigor index of P.orientalis and promoted seedlings growth.?2?The ingredients of the seed coating agent significantly improved the seeds germination effect.The optimum concentration of GA3 alone was 50 mg L^-1,the optimum concentration of Ge-132 was 5?mol L^-1,and the optimal concentration of SA was 1.5 mmol·L^-1.?3?The best combination of the ingredients was obtained by orthogonal test.The optimum combination was 50 mg L^-1 GA3+2.0 mmol L^-1 SA+7.5?mol L^-1 Ge-132,which significantly improved the germination rate and germination uniformity of the seeds.?4?Under drought-free stress conditions,the best seed coating formula was 0.2%CS+0.06 g nano-Ti O₂ and active ingredient 50 mg L^-1 GA3+2.0 mmol L^-1 SA+7.5?mol L^-1 Ge-132.The composite coating formulation significantly promotes seed germination and increases antioxidant enzyme activity and proline content.The seed coating formula also showed the best result under 5%PEG simulated drought conditions.The germination index,seedling biomass and antioxidant enzyme activities were significantly increased,and the content of PRO,SS and SP increased significantly while the content of MDA was reduced,which provided a favorable material basis for the growth of seedlings and the physiological activities under drought conditions and could be applied to seedlings of P.orientalis.