Population Characteristics And Seed's Biology Of Paeonia Ludlowii

The Paeonia ludlowii distributes in the southeast of Tibet which has high breeding and visual value. The article preliminary analyzes communities which are fit for it and besides, the natural and social factors which result it in endangered. Feasible germination method of seed was studied also. Thereupon scientific basis for P. ludlowii's protection and development were provided, as well as theoretical and practical basis for its introduction. The basic conclusion is as follows:(1) Because of social factors P. ludlowii population was short of young seedlings, and the old individual occupies most. At present, the population is maintained mainly by shooting of itself.(2) The height of P. ludlowii is directly proportional to age. Plants higher than 150cm occupied most. Height structure is related to population dynamic and physical environment.(3) The distribution pattern of P. ludlowii population is collective.(4) As for the nutritional elements in soil and plants, there was no significant difference among five locations, and as for the element contents in soil and plants organs, such as roots, stems and leaves are significantly different; contents between the nutritional elements also have significant difference. As for the accumulation indices of P.ludlowii, there was significant difference among five locations. When Linzhi population and Shannan population are variable, Na and Mn are significantly different, which is related to the difference of soil and climate between populations.P. ludlowii has strong adaptiveness which can grow normal in the soil which pH between 5.48-8.05 and organic matter is 5.69.(5) When the water content in seed drops to 6.38%, its vigor loses.(6) The physical obstacle of seed coat is not the predominant factor causing dormancy.(7) The biological test of germination inhibitory substance in different sits of seed: There are inhibitors in embryo and seed coat which can inhibit the growth of Brassica chinensis. The inhibitors can dissolve in the water and methanol but not ether and petroleum ether. The inhibitors in seed coat have light effect on the seed germination, and the inhibitors in embryo maybe have relation to the hypocoty dormancy, because it disappeared after germination.(8) The suitable pre-treatment and germination conditions: Soaking the seeds in 500ppm GA₃ for two days, and germination them under the conditions at 10-15℃and darkness .The seed will germinate after two months which need two years at least in nature. The Germination percentages of seeds treated with three hormones (GA3, 6-BA, ethrel) is Extremely low. Mix processing have instead affected the GA3 function. Corroding seed coat with vitriol cannot promote the seed to germinate, instead causes the seed easy to receive the bacterial infection, which affect the survival rate.(9) The seed of P. ludlowii has the phenomenon of double embryoes.