| In this thesis,the characters of sexual reproduction,asexual reproduction,saline-alkaline tolerance and chemical ecology of Apocynum venetum L.were studied by such methods as wild investigation,measure,field tests,green-house tests,physical and chemical analysis.The aims of this thesis are to find out the biological characters of A.venetum,excavate resource uses of A.venetum and discover the development ways of A.venetum resource,and to promote the resource to be developed quickly.In Songnen grassland,the distribution of A.venetum in Leymus chinensis meadow was shown in spot pattern.In the community of A.venetum,there were 31 species of plants such as L.chinensis and so on.The characters of sexual reproduction of A.venetumA.venetum comes to flower bud stage in the end of May,to initial bloom stage in the middle ten-days of June,to the full-bloom stage in the last ten-days and to the last bloom stage in the middle ten-days of July.Whole bloom stage of A.venetum spends more than 50 days.The every little flower blooms for 5-7 days.The fruit of A.venetum comes in the middle ten-days of July and is mature in the middle ten-days of Sept.Total little flower number of A.venetum plant was correlated negatively with the time when it came to initial bloom stage. Seed rate was correlated negatively with the little flower number.Seed rate of A.venetum was very low and it was just 0.8%.In the fruit that bloomed early,seed number was less than the one that bloomed late.The differences of 1000-grain weights between A.venetum that bloomed early and that bloomed late were not evident.The mean number of the first branch on one plant of A.venetum was 15.39.The number of the first branch on one plant in different population was 12.72～18.20 in the initial bloom stage and the lest one was 9,the most one was 23.But the numbers of little flower and fruit did not increase with the number of branch.The numbers of little flower on the main stem and first branch all decreased with the delay of initial bloom stage.Total number and mean number of little flower on the main stem are more than those on the first branch.Similar situation occur in fruit.Seeding rate of the main stem and first branch all increased with the delay of initial bloom stage.Seeding rate of main stem was higher than the one of first branch. Comparing with the first branch,the seed of main stem was fullerSexual reproduction of A.venetum is easy.The third day after sowing,plantlet occurred. Plantlet came out in the most amount in the 7th day.All plantlets had come out in 20th day. Plantlet rate in meadow soil was 86%.Sandy soil was 80%,alkaline meadow soil 48%and saline-alkaline soil just 20%.Even 20%plantlet rate,it still showed that A.venetum has strong saline-alkaline tolerance and A.venetum could be used pioneer plant when saline-alkaline soil needs to be recovered and meliorated.The characters of asexual reproduction of A.venetumThe segment from vertical root of A.venetum was good asexual reproduction material due to high survival rate.The segment of 2cm was not good reproduction material due to low survival rate.The 3cm segment and 5cm segment were best length for vertical root and horizontal root respectively.The last generation stage was the best time for collection of root segment.The 2cm segments of vertical root were treated by 50ppm ABT-1 and the survival rate of them reached 62.5%after growing in sandy soil for 3 months.It shows that ABT could promote survival rate of 2cm root segment of A.venetum remarkably and it would be good reproduction measure to use 2cm root segment with ABT treatment.Stem segment cutting of A.venetum was difficult.This problem needs to be studied further in future works.The characters of saline-alkaline tolerance of A.venetumThe soil samples from Songnen grassland were graded into 3 levels.The slight saline-alkaline soil insists of farm soil and abandoned cropland and the conductivity of the soil was below 200us/cm.Middle saline-alkaline soil insists of alkaline meadow soil and the conductivity of the soil was between 309-316us/cm.Heavy saline-alkaline soil insists of saline-alkaline soil and the conductivity of the soil was between596-956us/cm.Under the condition of saline-alkaline threatening:when the conductivity of the soil was below 309.00us/cm and pH was below 7.56,the increase saline-alkaline component could promote A.venetum plantlet to come.When the conductivity of the soil was over 309.00us/cm and pH was over 7.56,the increase saline-alkaline component could restrain A.venetum plantlet to come.When the conductivity of the soil reached 956us/cm and pH 9.87, saline-alkaline component restrained A.venetum plantlet to come completely.The increase of saline-alkaline component of soil could restrain growing of root and stem and biomass increase of root,stem and leaf.Under the condition of saline-alkaline threatening:A.venetum seed could germinate in incubator quickly and almost fully when the conductivity of culture solution was 1610-8010us/cm and pH was over 9.The result suggests that seed reproduction could become an effective reproduction model of A.venetum in practical production.But the result needs to be confirmed again due to some difference with the result from culture test in soil.The increase of saline-alkaline concentration restrained growing of radicle and embryo of A.venetumThe characters of chemical ecology of A.venetumThe content of crude protein in the leaf of A.venetum displayed an outstanding degressive trend from seedling period(21.33%),through blooming flower period(13.25%) and to fruit period(10.95%).It revealed that the feeding value is to decline continuously during whole growing and developing period.The change trend of contents of hydrolyzed amino acids in leaf of A,venetum was same with that of crude protein.It was degressive from seedling to fruit during whole growing and developing process.The content change of crude fat displayed 2 peaks.The first peak was in the 12th of June and the content reached 4.51%;the second peak was in 14th of Aug and the content was 5.81%.Fat content was high in fruit period and degressive in nutrition period after fruit.It means saved fat in leaf could be transferred to fruit and seed.Except one peak occurred in flower period,the content of soluble sugar in the leaf of A. venetum was a slow degressive tend.The peak means that soluble sugar correlated closely with physiological action of A.venetum during procreant period.As a grazing grass,the best collecting time of A.venetum was suggested in flower bud period according to above study results.In different organs,the highest content,12.89%,of total flavonoid was in flower.The second organ(7.21%) was in leaf and the third(1.92%) in stem.In root and fruit,just a little flavonoid occurred.According to the content and biomass of total flavonoid,leaf and flower of A.venetum were suggested to be the best organs used as natural medicineDynamic accumulation of total flavonoid in leaf of A.veneturn displayed one valley (blooming flower period) lying between two peaks(flower beginning period and fruit maturating period).It means that flavonoid could be transferred to flower from leaf in order to meet procreation need during procreating period.The accumulation mode of quercetin was same with the mode of total flavonoid.One valley(blooming flower period) lied between two peaks(flower beginning period and fruit maturating period).When meeting blood serum,the electron on the ring B-C and A-C of quercetin molecule would move and make -OHs of Ring B and A ionizated and one anion with double negative charge would present.The anion would connect with amino acid of white protein in blood serum by ionic band and enhanced fluorescence effect of white protein.The mechanism,point,intensity and model of connection of quercetin and white protein in blood serum have been revealed in this thesis and it would help us to know how effective compounds of A.venetum transfer and distribute in human body deeply and let us to know more knowledge about pharmacological effects of effective compounds of A.venetum.And it also has important value in molecular design of drug. |
PDF Full Text Request