Study On Seed Quality Classification Criteria And Priming Technology Of Paeonia Suffruticosa Andr.for Medicine

Paeonia suffruticosa Andr.is the woody perennials which was belonged to Paeonia under Ranunculaceae family.Cortex Moutan is the dried bark of Paeonia suffruticosa Andr.which is traditional Chinese medicine and widely used in clinical.Cortex Moutan was recorded in?Shennong'Herbal?.It has the effects of removing heat to cool blood and promoting blood circulation.Clinical applications:Febrile diseases,eruption exanthem,bleeding,anhidrosis,Menstrualdisorders or dysmenorrheal,Peri-appendicular abscess and skin infection.Seeds of P.suffruticosa have the problem of low germination rate,slow and uneven germination which have no salinity resistance and have a very confusion market.This study explored the Seed quality test methods of P.suffruticosa and the quality classification criteria of P.suffruticosa seeds have been initially established.Meanwhile,seed priming technology of nano-TiO2 under salt stress was applied in medicinal plants.The mail results were as follows:1.The seed quality of P.sufruticosa from different producing areas was measured based on the related seed testing regulations.The seed testing methods for quality items of P.suffrut.icosa was established preliminarily:The samples weight of P.suffruticosa were at least 7000 g for purity analysis and were at least 700 g for test.The phenotypic observation and size measurement were used for authenticity testing.The 1000-seed weight was determined by 100-seed method,and the water content was carried out by low temperature drying method(10 hours).After soaking in distilled water for 24 h,the seeds was treated with different temperature stratifications of day and night(25?/20?,day/night)in the dark for 60 d.After soaking in the liquor of GA3 300 mg·L-1 for 24 h,the P.suffruticosa seeds were cultured in wet sand at 15 ? for 12~60 days for germination testing.Seed viability was tested by TTC method.2.Thirty-one batches of P.suffruticosa seeds from different provenances were selected.The seed rooting rate,seed germination rate,seed purity,seed viability,1000-seed weight and moisture content were determined and analyzed through SPSS 20.0 software.Seed rooting rate,seed germination rate and seed purity were selected as the main index for classification,while 1000-seed weight,seed viability and moisture content could be used as important references.The seed quality grading of P.suffruticosa was described as three grades.The seed quality of each grade should reach following requirements:for first grade seeds,seed rooting rate?80%,seed germination rate?80%,seed purity?90%,seed viability?80%,1000-seed weight?250 g,moisture content?10%;for second grade seeds,seed rooting rate?50%,seed germination rate?60%,seed purity?70%,seed viability?75%,1000-seed weight?225 g,moisture content?10%;for third grade seeds,seed rooting rate?20%,seed germination rate?45%,seed purity?60%,seed viability?45%,1000-seed weight?205 g,moisture content?10%.The quality classification criteria of P.suffruticosa seeds have been initially established.3.Taking the non-priming and water-priming seeds as control,the effects of osmotic priming with 3 kinds of priming time and five kinds of nano-TiO2 concentration were studied on germination characteristics,seedlings biomass and photosynthetic characteristics of P.suffruticosa.The results showed that low concentration of nano-TiO2 promoted germination characteristics and seedlings biomass of P.suffruticosa significantly under 48 h priming time.The root rate,germination rate,seedlings height,lateral root number,fresh and dry weight of primed seedlings were significantly higher than those of control.Seedlings Pn and chlorophyll content reached the highest respectively under 48,72 h priming time at 2 mg·L-1 nano-TiO2,while other concentration had no significant influence on photosynthesis.4.Taking the non-priming and water-priming seeds as control,the effects of osmotic priming of nano-TiO2 under salt stress were studied on germination characteristics,seedlings biomass,lateral root number,the activities of peroxidase,superoxide dismutase and catalase,soluble protain,Pn and chlorophyll content of P.suffruticosa.The results showed that the germination of P.suffruticosa was inhibited under low concentration of NaCl stress.But the germination rate,seedlings biomass,lateral root number,autioxidant enzyme activities and chlorophyll content of primed seedlings improved significantly at 2 mg·L-1 nano-TiO2,under 48 h priming time.The Pn of P.suffruticosa improved significantly at 2~1000 mg·L-1 nano-TiO2,under 72 h priming time.