Omphalogramma souliei Franch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three...Omphalogramma souliei Franch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three populations of O. souliei in NW Yunnan, China. The genetic diversity at the species level is low with P=42.5% （percentage of polymorphic bands） and Hsp=0.1762 （total genetic diversity）. However, a high level of genetic differentiation among populations was detected based on different measures （Nei＇s genetic diversity analysis： Gst=0.6038; AMOVA analysis： Fst=0.6797）. Low level of genetic diversity within populations and significant genetic differentiation among populations might be due to the mixed mating system in which xenogamy predominated and autogamy played an assistant role in O. souliei. The genetic drift due to small population size and limited current gene flow also resulted in significant genetic differentiation. The assessment of genetic variation and differentiation of the endangered species provides important information for conservation on a genetic basis. Conservation strategies for this rare endemic species are proposed.展开更多
In the present paper,the chromosome numbers of three species of Omphalogramma from Yunnan,China are reported for the first time.The results are formulated as follows: O.delavayi 2n=48, O.souliei 2n=96, O.forrestii 2n=48.
基金supported by the National Basic Research Program of China (973 program,Grant No.2007CB411600)the Yunnan Provincial Natural Science Foundation (Grant No.2005C0051M)the National Natural Science Foundation of China (Grant No.30571137).
文摘Omphalogramma souliei Franch. is an endangered perennial herb only distributed in alpine areas of SW China. ISSR markers were applied to determine the genetic variation and genetic structure of 60 individuals of three populations of O. souliei in NW Yunnan, China. The genetic diversity at the species level is low with P=42.5% （percentage of polymorphic bands） and Hsp=0.1762 （total genetic diversity）. However, a high level of genetic differentiation among populations was detected based on different measures （Nei＇s genetic diversity analysis： Gst=0.6038; AMOVA analysis： Fst=0.6797）. Low level of genetic diversity within populations and significant genetic differentiation among populations might be due to the mixed mating system in which xenogamy predominated and autogamy played an assistant role in O. souliei. The genetic drift due to small population size and limited current gene flow also resulted in significant genetic differentiation. The assessment of genetic variation and differentiation of the endangered species provides important information for conservation on a genetic basis. Conservation strategies for this rare endemic species are proposed.
文摘In the present paper,the chromosome numbers of three species of Omphalogramma from Yunnan,China are reported for the first time.The results are formulated as follows: O.delavayi 2n=48, O.souliei 2n=96, O.forrestii 2n=48.
