Study On The Germplasm Resources Distribution And Conservation Breeding Of Endangered Plant Taihangia Rupestrisvar. Ciliata

Taihangia rupestris var.Ciliate is the most primitive diploid plant of the Rosaceae fairy wood family.It is an ancient genus,a species endemic to China,and a national secondary protected plant.It is only distributed on the cliff wall of the southern section of the Taihang Mountains.Due to its narrow distribution range,limited number of plants and special habitats,it has been assessed by IUCN?International Union for Conservation of Nature?as a critically endangered?CR?state,so it is urgent to establish an effective protection mechanism.At present,the research on the Taihangia rupestris var.Ciliate mainly focuses on the distribution of wild populations,introduction and cultivation,and the status of plant taxonomy.This paper starts from the perspective of germplasm conservation and ecology,and grasps the current survival of Taihangia rupestrisvar.Ciliate through field investigation.Detailed data on the status and geographical distribution,and then obtain relevant data on its ecological adaptability.The ecological model and ArcGis geographic information system are used to simulate the suitable area,and the key core protection habitats are identified.The origins of the Taihangia rupestrisvar.Ciliate seeds are taken in different ways.The research on the breeding method of the Taihangia rupestrisvar.Ciliate was carried out,and the management and protection suggestions were put forward according to the actual situation.The research results are as follows:1)After investigation,it was found that the Taihangia rupestrisvar.Ciliate is mainly distributed in the natural protection and surrounding areas of the Qingyazhai.The distribution range is roughly strip-shaped,which of the distance between east and west is about 8 km,the distance between north and south is 25 km,the area is about 250km²,and the elevation is from 700 m-1600 m.They are all distributed,mainly on the cliff wall with limestone as the parent material,arranged longitudinally along the cracks on the stone wall,and the platform below the stone wall is occasionally distributed,but the number is small.By investigating three natural habitats and three artificial cultivation samples,according to statistics,there are 122 species of associated plants of the Taihangia rupestrisvar.Ciliate,what belonging to 49 families and 103 genera,and there are 14 distribution areas in the flora composition.19 variants,mainly distributed in the north temperate zone.2)The fruits of Taihangia rupestrisvar.Ciliate are achenes.The seeds are long-elliptic,3-5 mm long and 1-2 mm wide.The stigma at the end of the seed is hairy,the seeds are brown,and the surface of the seeds is sparsely pilose.The seeds can germinate without dormancy,and the results of germination treatment of the seeds in the water bath show that?1?different the culture method had no significant effect on seed germination rate and germination potential.?2?when the water bath temperature is 40°C,the seed germination rate and germination potential are significantly higher than other temperature treatments,30°C-40°C.The germination rate and germination potential of seeds increased with the increase of temperature.From 40°C to 60°C,the germination rate and germination potential of seeds decreased with the increase of temperature.?3?When the treatment temperature of the seeds is the same,the difference of seed sources has little effect on the germination rate and germination potential.The germination potential of the seeds in the next year is lower than that of the new seeds,but the germination rate has not decreased significantly.3)Based on MaxEnt model to predict the suitable distribution area of Taihangia under current climatic conditions,the receiver operating characteristic curve shows that the AUC values of MaxEnt model training set and test set are 0.996 and 0.996,which are significantly higher than the random predicted AUC.The value?0.5?indicates that the model has a good fitting effect and the prediction data has high credibility.According to the distribution map of the suitable area of the species,the suitable area of the Taihangia is E 112.8°¹15.3°,N 33.2°³7.8°,and the area of high suitable area is800km²,mainly distributed in Hebei,Henan and Shanxi.The junction of the provinces,where is the south of Taihang Mountain.The MaxEnt model calculates the influence factors of different environmental variables on the species distribution.The precipitation is the main factor that dominates the distribution of the genus Taihang,and precipitation of wettest quarter?bio₁6?,annual precipitation?Bio₁2?,the temperature seasonality?Bio₄?,the precipitation of wettest period?Bio₁3?,the minimum temperature of coldest month?Bio₆?,the precipitation of warmest quarterly?Bio₁8?,and the temperature annual range?Bio₇?are the main factors affecting the distribution of the Taihangia..In the future climatic conditions,the main distribution areas of the adaptive areas of the Taihangia.are still concentrated in the junctions of Henan,Hebei,and Shanxi provinces.The high-adapted areas show a trend of increasing first and then decreasing.Around 2060 millennium,the high-adapted areas reach a maximum of831.54.km²,and it would shrink year by year.4)Based on the current research results and actual situation of Taihangia rupestris var.ciliata,Make the following suggestions:suggested adoption ways to deepen and expand in-situ conservation,strengthen the work of off site conservation,establish a scientific and effective research system and conservation breeding system,wild-exercising and returning nature,establish protection planning and digital management mechanisms and many more.