| As an important plant of traditional medicinal, Tripterygiun wilfordii Hook often bemixed planting with fir and other species in its nursery and growth process. For thepurpose that to improve the stability of plant communities and effect of pest-resistant, etc.However, more and more researches have shown that there has a evident allelopathyfunction between Tripterygium and fir. Endophytic fungi is this kind of fungi that livinginside of plant tissues and dont’t cause any obviously disease symptoms. The symbiontbetween fungi and plant also be deemde to as a universal phenomenon of nature.Otherwise, most of reports on palnt allelopathy function are disaffinity because of the vastmajority of rescently reasearches have not considered the impact of endophytic fungi. Upto now, no research has been reported on the host allelopathy function that caused byendophytic fungi of Tripterygium.At first, this reasearch will isolate and purify endophytic fungi from Tripterygium.Then use the liquid culture medium that obtained by suspend cultivation between callusand its endophytic fungis to start up the seed germination test on fir, and filter out one ofthe endophytic fungis that has the strongest allelopathy function. At last, obtain the tissueculture plants of fir by plant tissue culture techniques and start up the seed germination andpalnt appelopahy function test. In the order to explore the appelopahy function ofTripterygium fungi on fir. The results show as the below:1. Obtain22kinds of endophytic fungi by the means of separation fromorganizations of Tripterygium. Then use the liquid culture medium that obtained bysuspend cultivation callus and its endophytic fungis to start up the seed germination test onfir. The results have shown that the5thstrain has the strongest appelopathy function on firseed germination in all processing samples. The germination rate of5thstrain processingsample is only at29.67%and lower than the27%of CK processing sample. Itsgermination velocity only reaches at11.26, far below of23.73of CK’s. Above all, NS-5been chosen as the kind of fungi that have the advantage appelopathy function on fir.2. Carry out26s rDNA ITS sequence analysis on NS-5. The result have shown thatthe NS-5belongs to small thorns Penicillium genus and its Latin name is PenicilliumSpinulosum.3. Obtain9kinds of liquid culture medium through the separate culture and suspension co-cultured. Then use the liquid culture medium that obtained by suspendcultivation callus and its endophytic fungis to start up the seed germination test on fir andthen mensurate the changes of physiological indicators that under the stress. The resulthave shown that the nine kinds of culture medium processing have significant inhibition.The relative conductivitys are much higher than19.93%of the contarst. Soluble proteinand soluble sugar contents still higher than the contrast. Cause of the greatly reduced ofamylase activity, starchs accumulate inside of fir and the content of it in nine kinds ofprocessing are higher than the control plots. Furthermore, by comparison, the germinationinhibition function on fir is stronger of ndophytic fungi culture medium processing thanTripterygium callus’.4. Use fir tissue culture plants as the receptor materials, and then mensurate thegrowth conditions and varieties of physiological and biochemical enzyme activity underthe stress of nine kinds of culture medium. Results be found by the mensuration of thephysiological and biochemical indexes in the growth process. Nine kinds of culturemedium can cause the allelopathic stress on the growth of the fir plantlets and allelopathiceffects can be more stronger when the two suspension co-cultured. All the growth trendof nine kinds of medium processing have large fluctuations and even appeared the withered,dead seedling phenomenon in the end of trial. All the physiological and biochemicalindices in the first two test time have increased and then showed a apparent downwardtrend after certain upward. With the intensification of stress time, the plants can notwithstand the intense stress of injury. It has called the increase of MDA content, cellmembrane permeability and the POD activity, and the reduction of soluble protein content,SOD activity, CAT activiy and the metal element content. This kind of result may beexplained as that the short-term culture medium has a certain role in promoting the growthof fir. However, according with the endurance reached a critical point along with thecontinued extension of the time, the medium will be has powerful inhibition and stressinjury.5. Use Hitachi HPLC to detecte the nine kinds of liquid culture medium and find theirchromatograms are similar with each other. It has indicated that there have the same or similar compounds in these nine mediums. However, the initial determination based onpeak area of these compounds found they have different concentrations, and endophyticfungi culture medium and suspended co-cultured are slightly higher than the callus’, whichmay be the reason that the allelopathic of the first two fir seed germination and growth offir tissue culture process are stronger than the callus’. Used LC-MS to detecte the Y3, N3and Y+N3medium and found that the three suspended culture medium contain the similarcompound components. The difference is not obvious. Some of these ingredients haveexisted in all three mediums, and some ingredients are unique. The substance with amolecular weight of203.4be found in the three kinds of culture msdium when detected inthe positive ion mode, and242.2be found in all of them when the negative ion mode beused.In summary, endophytic fungi inside the Tripterygium has allelopathy fuction and acertain degree of inhibition both in the fir seed germination and the growth of fir plantletsgrowth. Chromatography and mass spectrometry analysis showed that allelochemicalscomponent of funi mediums are similar, and have the differences only on concentration.All above have illuminate that the endophytic fungi of Tripterygium has the effect on hostallelopathy only by the concentration of allelochemicals rather than the different types ofallelochemicals. |
