Studies On Germplasm Resources And Seed Oil Fatty Acids In Wild Populations Of Acer Truncatum

Acer truncatum Bunge is belonging to the genus Acer,which is a unique oil plant in China.Since the 1970 s,A.truncatum has been vigorously developing and promoting in China.However,the situation of wild germplasm resources is still unclear.In response to this situation,this study first investigated the wild populations of A.truncatum germplasm resources in China.On this basis,We studied the leaf,fruit and seed phenotypic traits,seed oil content and fatty acids compositon of A.truncatum.The main conclusions are as follows:1.A.truncatum main distribution range was from 106.00°~120.01° E and 31.81°~43.85° N;the vertical height was between 442 and 1393 m,and wild populations were mainly distributed between 500 and 900 m.The main distribution area spanned temperate continental climate,temperate monsoon climate and subtropical monsoon climate,which had significant differences in temperature and precipitation.The annual average temperature was between 2.0 and 15.4°C,the annual rainfall was between 350 and 1200 mm,and the area which the annual average temperature was 11~15? and the annual average rainfall was 600~700mm had the most distributed populations.2.The distribution density of wild A.truncatum in different regions was quite different,the P1 and P3 were distributed in blocks,while the rest were concentrated and scattered.Most natural populations were spreaded over the valley bottom and shadow of gravel soil,and a few populations were distributed on the top of the mountain.3.The wild populations of A.truncatum were mainly secondary forests,botanicaland and fruit economic traits,the community composition,associated and dominant plants of different natural populations had clear distinctions.4.The variation coefficient(CV)of phenotype traits of ten wild A.truncatum areas ranged from 4.65% to 40.34%,and the laminae fissure width(LFW)had the largest variation,while bears the mark(BTM)was the most stable traits.Principal component analysis showed that the main variation sources of wild A.truncatum was fruit>leaf>seed.Correlation analysis of the phenotypic traits revealed that the relationship between fruit and seed was close,and the correlation between leaf-related traits and seeding was not significant.The correlation analysis between geo-ecological factors and phenotypic traits showed that the latitude and longitude had significant effect on fruits and seeds,and the average annual temperature had significantly impact on leaf.The 10 populations of wild A.truncatum clustered into 4 groups according to cluster analysis.5.Changes of seed oil content in different populations were small,ranging from 29.20% to 44.11%.We detected 13 fatty acid components and discovered seed fatty acids composition of 10 populations was basically same.The proportion of 6 unsaturated fatty acids was as high as 90%.The degree of variation among fatty acid components was different,and the unsaturated fatty acids were the most stable,while the tar acid was the most discrete.The ratio of polyunsaturated fatty acids to(saturated fatty acids + monounsaturated fatty acids)was less than the value 1,indicating that wild populations of A.truncatum seed oil had great potential for developing biodiesel.6.The correlation between fatty acids composition and temperature was significant,and the relationship with other geo-ecological factors was weak.And there was a significant positive correlation between unsaturated fatty acids and seed size.In addition,fatty acid components were grouped into three categories by cluster analysis,and the correlation with geographical distance was significant.