Phylogenetic relationship analysis of European plum in Xinjiang based on pollen microscopic characteristics

【Objective】To explore the phylogenetic relationship and evolution degree among various typesof European plum germplasm resources in Xinjiang.【Methods】The pollen morphology characteristics of29 Xinjiang European plum accessions which classified into 5 types were observed and analyzed by scan-ning electron microscope.【Results】The results showed that pollen grain of tested accessions were all iso-polar and actinomorphy single pollen,the germinated organ belonged to N3P4C3 type. The average polaraxis length ranged from 27.70 μm to 41.47 μm,and the equatorial axis length ranged from 14.67 μm to21.34 μm. The polar axis and equatorial axis variation coefficients were 8.88% and 7.51%,respectively.Among 5 European plum types,Tacheng Binzi and Tacheng smoked plum had the same exine ornamenta-tion and mostly belonged to“fringe- perforate”type. The other European plum types,Jiashi smokedplum,introduced European plum varieties and wild European plum mainly belonged to“verrucous-perfo-rate”,“fringe/cerebroid-perforate”and“wide fringe /verrucous-perforate”types,respectively.【Conclu-sion】The pollen morphology characteristics of Xinjiang European plum had a certain genetic diversity,which were mainly embodied among different types. Cluster analysis showed that Jiashi smoked plum andwild European plum had the near phylogenetic relationship. However,the introduced European plum vari-eties,Tacheng smoked plum and Tacheng Binzi had the near phylogenetic relationship. The evolution degree of Xinjiang European plum types from low to high might be as follow: Jiashi smoked plum,wild Euro-pean plum,introduced European plum varieties,Tacheng smoked plum and Tacheng Binzi.