Taxonomic Study Of Acer Mono And Acer Truncatum In Liaoning Region Based On Phenotype And Molecular Markers

Acer mono and Acer truncatum have special leaf type and bright autumn leaf color.They are important forest tree species and excellent leaf-viewing tree species in north China.They are widely used in landscaping and have important application value.The morphology of Acer mono and Acer truncatum is similar and the variation types of Acer mono Maxim.are diverse,which causes great difficulties in its development and utilization.Therefore,this study combined phenotypic morphological classification,pollen morphological classification and SSR molecular marker classification to conduct the classification study on different provenances of Acer mono and Acer truncatum in Liaoning region.The results were as follows:1.Based on the changes of phenotypic traits,the natural distribution of two maples in Liaoning region was as follows: Acer mono was mainly distributed in Liaodong region,while Acer truncatum was mainly distributed in Western Liaoning region.Through the four characters of middle lobe width,leaf base Angle,fruit length and fruit wing ratio,47 different provenances of Acer mono and Acer truncatum were distinguished.When the fruit-wing ratio was greater than 1.4,it was Acer mono When the fruit-wing ratio was less than 1.1,it was Acer truncatum.The frust-wing ratio was between 1.1 and 1.4.When the leaf base Angle was less than 100°,it could be judged as Acer mono,and when the leaf base Angle was more than170°,it could be judged as Acer truncatum,Thirty-six samples were identified based on phenotypic traits.2.The provenance samples of Huanren County,Dongling District and Jianchang County in representative areas were selected for the study of pollen morphology,and it was found that apart from the slight difference in the depth of the net ridge,the pollen outer wall decoration of the three provenances tended to be the same for Acer mono and Acer truncatum.However,there were significant differences in four quantitative characters,including bending degree,polar axis length,groove spacing and volume size,between Acer truncatum and Acer mono from different provenances.3.SSR molecular markers were used to study 47 samples with 23 pairs of primers,and 7pairs of primers with good repeatability,clear target band and high polymorphism were selected.The clustering results showed that 47 samples were separated according to geographical trend.Three pairs of primers(AM118,12C080586(7)and 12C080590(1))were selected according to the number of various qualitative specific alleles,and fingerprints were established.In addition,primers 12C080590(91)and 12C080592(93)were found to be suitable for the interspecific classification of Acer mono and Acer truncatum.4.Chi-square test showed that phenotypic clustering and molecular clustering had a very significant correlation.The difference of pollen phenotypic traits in different Acer mono and Acer truncatum was not as significant as that in leaf and fruit phenotypic traits.