Phylogenic Of Stigonema Ag. From Northern China

Stigonema Ag.belongs to Cyanophyta,Stigonematales,Stigonemataceae,which have complex true branch and various species.It's also the only genera of stigonemataceae which was reported in China.In order to study phylogenetic relationships of Stigonema Ag.,we combined traditional morphological with molecular biology methods for systematic research of Stigonema Ag.from the northern parts of China.In this study,we collected a total of 1469 Stigonema Ag.environmental sample were placed under BX53 microscope morphology,identified Stigonema Ag.species and microscopic photograph retained.Meanwhile,according to the literature and retrieve table,Stigonema Ag.was detailed morphological description,then was writed retrieval table.In addition,the use of BG11 and CT medium pure culture algal strains.Based on 16 S rRNA and nifH gene molecular markers,environmental samples using the whole cell and the algae strains applying pure culture method respectively were amplified by PCR.The PCR product was cloned and sequenced,finally obtained 7 partial sequence of 16 S rRNA gene and 16 partial sequence of the gene nifH.Sequences obtained were constructed NJ phylogenetic tree by employing MEGA 6.06 software,and genetic relationships among species of Stigonema Ag.was studied based on morphologic and molecule system methods.At the same time,with fraction species of Cyanophyta Nostocales ? Stigonematales constructed NJ phylogenetic tree to clarify the origin of Stigonema Ag..The results of morphology showed,there were Stigonema ocellatum,Stigonema ocellatum var.braunii,Stigonema hormoides,Stigonema hormoides var.tenue,,Stigonema dendroidecum,Stigonema aerugineum,Stigonema panniforme,Stigonema scytonematoides,Stigonema tomentosum,Stigonema nanxionggensis,Stigonema gelationsum,Stigonema turfaceum,Stigonema informe,Stigonema mamillosum,Stigonema lavardei,Stigonema minutum,Stigonema expansum,Stigonema sinuatum and 2 Stigonema sp.that can't be determined by morphology from Northern China.Molecular systems study results show that Stigonema Ag.is monophyletic.