基于自交率的基因型信息熵变规律与自花传粉机制的进化意义  

Laws of Change Entropy in the Population Pollinating by Means of both Self-Pollination and Cross-Pollination and the Evolutionary Significance of Selfing Mechanism

作　　者：李大林[1] 陈奇[1] 

机构地区：[1]柳州职业技术学院基础部,柳州545006

出　　处：《上海交通大学学报（农业科学版）》2008年第6期588-591,598,共5页Journal of Shanghai Jiaotong University(Agricultural Science)

基　　金：国家自然科学基金(30671111);广西教育厅科研项目(200807MS065)

摘　　要：用离散线性系统研究多对独立杂合基因在兼有自花与异花传粉群体中的基因型信息熵逐代演变规律,推导出极限平衡状态基因型信息熵是自交率的凸函数,当a=0.5时其值最大。在趋向极限平衡进程中,基因型信息熵曲线当a>0.5时先升后降,当a≤0.5时单调上升,当a→0+时以Hardy-Weinberg平衡熵为极限。在某一世代,群体基因型信息熵与独立杂合基因对数成正比。发现群体中存在一定比例的自交,能提高变异程度,甚至超过随机交配群体的变异,认为这是自花传粉机制的进化意义。Based on the discrete linear system, this text studies the laws of the change of the genotype entropy generation after generation for the population pollinating by means of beth self-pollination and cross-pollination with many pairs of independent heterogenes, deducing that the genotype entropy in the limit equilibrium state is the convex function of the selfing rate and it reaches a maximum value when. In course of a population＇s tending to equilibrium, the value of the genotype entropy first rises and then drops when , and merely rises while , and its limit is the Hardy-Weinberg entropy value when. The genotype entropy of a population in certain generation is proportional to the pairs of the independent heterogenes. If there is a certain percentage of selfing in a population, the probability of variation can be increased, which even exceeds the variation of a panmixis. This is regarded as the evolutionary signiticance of self-pollination.

关 键 词：信息熵 自交 自花传粉 Hardy-Weinberg平衡 离散线性系统 

分 类 号：Q347[生物学—遗传学]