Sexual Reproduction And Tissue Culture Of Epimedium Wushanense

Epimedium wushanense is a perennial medicinal plant of the Berberidaceae family.In this thesis,the development of inflorescence and flowers,seed germination and tissue culture were used as experimental materials to observe the reproductive changes in the development of inflorescence and the pistils of flowers in E.wushanense by applying microscopy and paraffin sectioning techniques;the best method of seed germination was investigated by using three different treatment conditions,namely erythromycin soaking,temperature lamination and room temperature shade drying;the cotyledons of germinating seedlings,the The cotyledons,the apical part of the total petiole and the stem of the germinating seedlings were selected as explants to explore the optimal way of tissue culture for the rapid propagation of E.wushanense.The main findings of the study are as follows.1.Observation on the development of inflorescence and flowers of E.wushanense.The inflorescence of E.wushanense is a panicle,and the inflorescence development process can be divided into the bud growth period,the inflorescence primordium differentiation period,the inflorescence formation period,the flower organ differentiation period and the fruit maturation period.The development of the inflorescence begins with the onset of underground buds after the fruit has matured,each inflorescence is lateralised by a pair of ternate leaves;3-4 inflorescences can be formed on each bud,these inflorescences are arranged in a stepped pattern on the bud,the closer to the main inflorescence the faster the development,the more distant the slower the development.The type of cytoplasmic division in the meiosis of the microsporophytic mother cells of E.wushanense is simultaneous;the tetrads formed by meiosis are tetrahedral in structure;the felted layer is deformed and the mature pollen is 2-cell pollen;in addition,the microspore development within the same anther is synchronous,while the microspore development between different anther cells shows asynchrony.The pistil is hollow,the ovary is unicarpic and 1-celled,thickly beaded,containing 9-12 ovules,anatropous ovules,and marginal placentas.The tetrads formed by the macrospore mother cells after the second meiosis are arranged in a straight line,followed by the development of functional macrospores near the commissure,the remaining three degenerating in development;the embryo sac development type is Liao type;the mature embryo sac is a seven-celled,eight-nucleated embryo sac.2.Study on the rapid germination method of E.wushanense seeds.The higher the concentration of gibberellin,the greater the seed germination rate.4 and 15 are the key temperature layers for breaking dormancy and promoting germination of E.wushanense seeds.4 lamination is beneficial to the growth of embryos and 15 lamination is beneficial to the release of seed dormancy.The 4/15°C variable temperature lamellarization is the best treatment for rapid seed germination as it can both release the seed from dormancy and promote the growth of the embryo.The longer the drying time,the more difficult it is to germinate the seeds,the lower the seed germination rate and the greater the rate of seed rot;and the germination rate of seeds from the drying treatment and the control group changed very little after 150 d of incubation and almost nothing after 210 d.The best performing treatment in the seed germination study was a variable temperature laminate treatment of4/15°C at 10 d intervals,which resulted in a germination rate of 93%.3.Tissue culture study of E.wushanense.The best sterilization method is to sterilize the whole seedling first and then cut it into parts by 0.1% Hg Cl2 for 6 min,rinse it 5-6 times and then debrush it in a Petri dish,the contamination rate can be controlled to about 15%;the best medium for induction of healing tissue in cotyledons,stems and total petiole tips is 1/2 MS +2 mg/L 2,4-D + 0.5 The best medium for the induction of healing tissue was 1/2 MS+ 0.5mg/L 2,4-D+ 0.1 mg/L 6-BA.