Effects Of Different Treatments On Seed Dormancy And Germination Of R.Simsii And R.Mucronulatum

We used the seeds of R. simsii and R. mucronulatum as our experimental material. Different concentrations of sulfuric acid, organic solvent and oxidizing agent were used to deal with the seed coats different time respectively, and then made germination experiment in petri dishes. Then the seeds were put into petri dishes and made them to sprout as well as the seeds which were treated by GA3, lamination, and alternating temperature. The light-demanding experiment was done in the1/4Anderson medium. The main results were summarized as follows:1. The seeds of rhododendron are so small that the one thousand-seed weight is just0.12g. The seeds sprout hard. The size of the seeds was not changed after being dipped in water72hours, which suggested that the inhibition of the seed coats was a important factor to influence germination.2. The germination of rhododendron seeds was effectively promoted after being treated20min by40%H2SO4,10-30min by100%aether,10-20min by3.0%H2O2,10-20min5.0%NaCIO. Being treated20min by100%aether was best for R.. simsii and lOmin for R.. mucronulatum.3. GA3is a important hormone in breaking the seeds dormancy. Our experiment suggested that the Germination rate, Germination potential, Germination index of the seeds of R.. simsii Planch. and R. mucronulatum Turcz were promoted after being treated by GA3, especially being treated20min by1.5mg/mL GA3.4. Lamination and alternating temperature could promote the germination of the seeds, especially being treated60d by Lamination and20circulations by alternating temperature with6h as a cycle. Alternating temperature is a imitation of lamination.5. Germination of many kinds of seeds needs light. In the light-demanding experiment, the seeds were sowed on1/4Anderson medium. Part of the seeds was covered so that the seeds could not receive the light. Put the other seeds which could receive the light as control. The result suggested that the illumination was essential to the seeds germination of R. simsii and R. mucronulatum.6. The activity of a-amylase was promoted in the earlier stage of germination after being treated20min by GA3,60d by lamination20circulations by alternating temperature with6h as a cycle.