Study On Conservation Biology Of Musella Lasiocarpa (Musaceae) Endemic To China

As an ancient species endemic to China, Musella lasiocarpa is a large perennial tufted herb, belonging to the Musaceae family, have high ornamental and economic value. It is widely cultivated in most parts of Yunnan Province and parts of Sichuan Province. Some scholars believe that its wild populations are difficult to determine or are already extinct. We have been discovered multiple M. lasiocarpa wild populations in cliff habitats in Yunnan and Sichuan Provinces, the living environment and scale are facing the challenges of a rapidly shrinking. In this paper, as the guiding ideology of conservation biology, to gain a better understanding of the populations distribution, phylogenesis, the role of low-copy nuclear gene phylogeny of M. lasiocarpa, genetic diversity as well as the historical events which lead to speciation, an integrated study of many of M. lasiocarpa was undertaken by means of population ecology, phylogeographical analysis caused endangered reason divided ESU protection unit put forward viable protection strategies.1.Population Numbers and Distribution CharacteristicsSurvey conducted in69cities and counties in Yunnan and Sichuan Provinces. We found9populations and2607（1011） individuals. The presence of nine counties wild M. lasiocarpa resources in widespread population size is small a limited number of individuals within populations. A minimum number of M. lasiocarpa population of only have54and sparser density. The larger the distance between individuals M. lasiocarpa wild resources habitats relatively poor. Eight populations growing in hillside slope greater than50degrees, some populations even born in a near-vertical cliff, high seed setting percentage but there germination rate is low or the phenomenon of the deep dormancy, it makes to M. lasiocarpa wild smaller number. The short-term replacement of old can only rely on asexual reproduction, so there are to difficult to rely on natural pollination, natural hybrids heterozygous in the short term. From villagers learned that when we asked in the survey, M. lasiocarpa of some locations has been destroyed30years ago. Now many populations of M. lasiocarpa number is gradually decay.2.PhylogeographyIn total,127individual plants from9M. lasiocarpa wild populations were used as study materials, and three chloroplast gene fragments, psbA-trnR, frnL-F and rpl16, were amplified. Ten haplotypes （Hap₁～10） were obtained, with a haplotype diversity index （Hd） of0.878and a mean gene flow among populations （Nm） of0.02. Analysis of molecular variance showed that genetic variation was97.62%among populations and2.38%within populations. Permut analysis showed that the level of genetic differentiation among populations （GST） was rather high （0.940） and NST was greater than GST.This suggested that the gene flow among9M. lasiocarpa wild populations was rather weak and the genetic variation among populations was far greater than that within the populations. In addition, there existed a certain geographic pedigree structure. Mismatch distribution analysis showed that there was no population expansion or bottleneck effect occurring in M. lasiocarpa wild populations. Both the phylogenetic tree created by PAUP and the kinship diagram created by Network divided the9populations into two clades, which were clearly geographically isolated. Analysis of wild population differentiation using Beast and Figtree softwares showed that the9populations were differentiated into two clades at4.4533million years ago （Mya） in the Tertiary. The Yanbian, Panzhihua population, Wenquan, Lijiang population and Jinjiang, Lijiang population were differentiated relatively early in the Quaternary. Based on the above results, we deduced that the origin of the M. lasiocarpa wild populations was located at the Lijiang segment of the Jinsha River, close to Yanbian, Panzhihua. The differentiation was caused by the uplift of the Qinghai-Tibet Plateau, Hengduan Mountain orogeny, and westward retreat of the ancient Mediterranean Sea. The main factors that contributed to the fragmentation of the M. lasiocarpa wild population habitat were diversion of the Red River and stream capture of its tributaries.3.Low-copy Unclear GeneIn total,127individual plants from9M. lasiocarpa wild populations were used as study materials, and Low-copy unclear gene fragments, CHIX, were amplified. Eleven haplotypes （Hap₁～11） were obtained, with a haplotype diversity index （Hd） of0.982, nucleotide diversity index Pi=0.08193and a mean gene flow among populations （Nm） of0.32. Analysis of molecular variance （AMOVA） showed that genetic variation was97.62%among populations and2.38%within populations. Permut analysis showed that HS=0.159, HT=0.973, the level of genetic differentiation among populations （GST） was rather high （0.845） and NST was greater than GST.This suggested that the gene flow among9M. lasiocarpa wild populations was rather weak and the genetic variation among populations was far greater than that within the populations. In addition, there existed a certain geographic pedigree structure. Mismatch distribution analysis showed multiple peaks and neutrality tests showed that there was no population expansion or bottleneck effect occurring in M. lasiocarpa wild populations. This is the same as the analysis of the chloroplast DNA.4.ESU Establishment and Endangered HierarchiesCombined with the actual endangered characteristics, considering the number of of M. lasiocarpa wild populations, flowers （bracts） color, genetic diversity. According the related results of population ecology and genetic diversity, Musella lasiocarpa wild populations recommended divided into EN or VU level, list the need to give priority to the protection unit of the population in the9wild populations, take the9wild populations divided into three the ESU protection unit.5.Induced the Endangerment Factor Analysis and Put Forward the Protection StrategyM. lasiocarpa endangered status is obvious, not only poor habitat, but also presents the fragmentation, distribution area is narrow, shrinking population size, small number of individuals in serious condition, important causes of low seed germination rate and genetic diversity of among populations are high, weak gene flow between the populations of these are caused by the M. lasiocarpa wild populations continued to shrink. According to survey of M. lasiocarpa wildlife resources resulting to the presence of endangered endangerment factors both inside and outside. Internal factors affect mainly because of their own seeds, breeding, genetic diversity, population diffusion and natural regeneration ability, external factors mainly due to the survival of the environment, human and livestock, climate change, and a series of interference caused. Through specific analysis we get a preliminary idea of protection measures, the effective protection of the population resources ex-situ conservation and reintroduction of these two methods are more suitable for this stage of M. lasiocarpa...