Effects of Different Exogenous Hormones on Germination of Fresh Seeds and Seedling Growth of Amomum tsaoko

Purpose To solve the problems of long seedling raising cycle and slow seedling growth in the seed dormancy period of Amomum tsaoko.

Methods Fresh seeds of A. tsaoko were treated with different exogenous hormones, and the effects of hormones on seed germination and seedling growth were investigated.

Results Treatments of 50 mg/L indole 3-acetic acid (IAA), 200 mg/L gibberellin (GA₃) and 10 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) could effectively reduce the germination start-up time of A. tsaoko seeds, improve the index of seed germination and promote the seed germination. The sprouted seedlings grew better and could accumulate more biomass. Among these treatments, the treatment of soaking the seeds in 50 mg/L IAA had the shortest germination start-up time (55 days), the highest germination rate (57%) and germination index (0.86). The sprouting seedlings under this way grew well, and the contents of soluble sugar, soluble starch, soluble protein and peroxidase activity were higher than other treatments. The treatment with 10 mg/L 2,4-D and 10 mg/L 6-benzyladenine (6-BA) changed the distribution of seedling biomass, and the root shoot ratio closed to 1∶2.

Conclusion This study initially reveals the effects of different exogenous hormones on seed germination and seedling growth of fresh A. tsaoko, which provides a certain basis for the breeding of fine varieties of A. tsaoko.