内蒙古荒漠草原植物遗传多样性对模拟增温处理的响应

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 内蒙古荒漠草原植物遗传多样性对模拟增温处理的响应 DOI: 10.5846/stxb201504220826 作者: 作者单位: 中国农业科学院草原研究所;内蒙古农业大学生命科学学院,中国农业科学院草原研究所：内蒙古农业大学生命科学学院,中国农业科学院草原研究所,中国农业科学院草原研究所,内蒙古农业大学生态与环境学院,中国农业科学院草原研究所;内蒙古农业大学生命科学学院 作者简介: 通讯作者: 中图分类号: 基金项目: 内蒙古自治区自然科学基金资助项目（2015MS0305）；中国科学院西部之光“人才培养”项目；中国农业科学院草原研究所科技创新工程资助项目 The response of genetic diversity in desert steppe plants to simulated warming in Inner Mongolia, China Author: Affiliation: Institute of Grassland Research, Chinese Academy of Agricultural Sciences;College of Life Sciences, Inner Mongolia Agricultural University,,,,,Institute of Grassland Research, Chinese Academy of Agricultural Sciences;College of Life Science, Inner Mongolia Agricultural University, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为探究全球变暖对温带荒漠草原地上种群的遗传影响，对已经接受模拟增温处理6年的短花针茅草原4种不同生活型植物，即半灌木、多年生禾草、多年生杂类草和一年生植物，应用AFLP分子标记方法研究了其遗传多样性和遗传结构。结果显示，对照处理与增温处理下的木地肤、短花针茅、细叶葱、猪毛菜4种植物的多态位点百分率（PPB）分别为11.32%，11.32%；40.83%，39.91%；14.29%，13.10%；19.85%，19.12%。Nei's基因多样性指数（He）分别为0.0274，0.0259；0.0812，0.0899；0.0131，0.0084；0.0506，0.0456。Shannon's信息指数值（I）分别为0.0447，0.0430；0.1354，0.1466；0.0267，0.0182；0.0811，0.0733。分子方差分析（AMOVA）显示4种植物的变异主要来源于实验处理内部，木地肤为85.03%，短花针茅为66.35%，细叶葱为70.00%，猪毛菜为66.52%；增温处理间的变异分别占-2.81%，-5.47%，-3.60%，2.53%（P>0.05）。4种植物增温处理与变异程度之间在统计学上并无相关性。研究表明虽然短时间的模拟增温并不足以使4种生活型植物种群遗传多样性和遗传结构发生显著变化，但相对于3种多年生植物，一年生植物猪毛菜更容易受到增温影响。多年生和一年生植物对增温具有不同的遗传响应。 Abstract:Climate is the most important factor that determines vegetation types and the distribution of species, and, accordingly, these features are two of the most prominent indicators of climate change. Currently, scientists generally agree that climate change will inevitably lead to changes in plant community structure and function, and if this change continues, the effects will be profound and enduring. Existing research shows that simulated warming causes an increase in biomass in Deschampsia caespitosa, Carex alrofusca, and Leymus chinensis; as climates change, these constructive species and their main companion species within a Kobresia humilis meadow have experienced an advancement in their spring phenology and a delay in their autumn phenophase. In addition, the photosynthetic rate of Deschampsia caespitosa in a Northwest Sichuan alpine meadow has increased. Although the change in stomatal conductance was irregular, a significant decrease has also been observed in the sodium, potassium, and phosphorus content of leaves. However, relatively little research has been conducted on the effects of simulated warming on the genetic structure and diversity of plant populations. Against the background of global climate change, the temperatures of the Inner Mongolian desert steppe have become unevenly elevated, with average annual temperatures increasing from 8.1℃ in the 1950s to 9.0℃ in the 1990s. The present study explores the effects of global warming on the genetics of wild forage plant populations with different life forms in desert steppe habitat, in an effort to elucidate their potential to adapt to environmental change. The study site was located in the desert steppe in Siziwangqi territory of Inner Mongolia. Suspension infrared radiators were used to create a controlled warming experiment under otherwise natural field conditions. Warming began on May 3, 2006. The average soil temperature at depths of 0, 7.5, 15, 30, and 50 cm increased by 1.32, 0.92, 0.88, 0.80, and 0.74℃, respectively, after warming for 1 year compared with the average in plots not exposed to warming. For this study, changes in genetic diversity and structure were analyzed in four plant populations: (1) small half shrubs, represented by Kochia prostrata; (2) perennial grasses, represented by Stipa breviflora; (3) perennial forbs, represented by Allium tenuissimum; and (4) annuals and biennials, represented by Salsola collina). The study was conducted under simulated warming pressure and genetic analysis was performed using amplified fragment length polymorphism. The percentages of polymorphic loci in K. prostrata, S. breviflora, A. tenuissimum, and S. collina under non-warming were 11.32%, 40.83%, 14.29%, and 19.85%, whereas those under simulated warming were 11.32%, 39.91%, 13.10%, and 19.12%, respectively. The genetic diversity of the four populations measured under control and simulated warming, measured by the Shannon's information index, were as follows: K. prostrata (0.0274, 0.0259), S. breviflora (0.0812, 0.0899), Allium tenuissimum (0.0131, 0.0084), and S. collina (0.0506, 0.0456). These findings exhibited the same distributional pattern as that of Nei's genetic diversity index for K. prostrata (0.0447, 0.0430), S. breviflora (0.1354, 0.1466), Allium tenuissimum (0.0267, 0.0182), and S. collina (0.0811, 0.0733). Cluster analysis of these four species showed that known of the species reacted significantly to the warming process, and that inter-individual clusters were not significantly different. The results of an analysis of molecular variance (AMOVA) indicated that the main source of variation among the four life form populations was within-population variation: K. prostrata (85.03%), S. breviflora (66.35%), A. tenuissimum (70.00%), and S. collina (66.52%). The among-groups variation was not significant and accounted for the following percentages of variation: K. prostrata (-2.81%), S. breviflora (-5.47%), Allium tenuissimum (-3.60%), and S. collina (2.53%). No statistically significant correlation was found between simulated warming and genetic differentiation. This study shows that a short period of simulated warming was not sufficient to create a significant change in genetic diversity and structure for the four life form populations studied here; however, compared with the three types of perennials studied, the annual plant S. collina, is more susceptible to the effects of warming. Perennials and annuals have different genetic responses to warming. This study provides experimental evidence that can reveal the potential adaptation of plants to environmental change for different life forms of wild forage plants of the desert steppe, and will help researchers to predict forage yield and changes in forage quality. 参考文献 相似文献 引证文献