近交衰退

四合木种群较高的遗传多样性和极低的种群间分化，说明不同的种群可能有共同的起源，随机遗传漂变和近交衰退不是影响遗传多样性的主要过程。

The high intrapopulation variation and low interpopulation differentiation could explained that the different populations might originate from the same one and genetic drift or inbreeding depression had not influenced primary process of genetic diversity .

结果也显示，在不同个体之间近交衰退程度存在明显差异。

There were significant differences in inbreeding depression between the families or mating parents .

利用中国原产PCNA品种可克服近交衰退，并为柿育种提供新的策略，具有推动加速培育新PCNA品种的潜力。

The use of Chinese cultivars offers a new strategy for persimmon breeding by overcoming inbreeding depression , and has the potential for progressing the breeding of new PCNA cultivars .

按群体平均数计算，这些性状F2的中亲优势仅为－1.99%～1.11%，这揭示出F2、F3近交衰退很少。

The average heterosis of F2 over mid - parent based on population mean was - 1.99 % to 1.11 % for all these traits . It suggests that little inbreeding depression exists for F2 and F3 seeds .

近交衰退的遗传基础，不能以简单的模式来说明。

The genetic basis of inbreeding depression cannot be explained by means of simple model .

近交衰退是生物界普遍现象，但其机理不清。

Inbreeding depression is common in the world , but its mechanism is not clear .

雌雄异株的进化，避免了近交衰退和提高了沙棘的适合度。

The evolution of dioecism has avoided the decline of inbreeding and improved the suitability of seabuckthorn .

在考虑近交衰退的影响后，遗传多样性水平降低，灭绝率提高；

When considering inbreeding depression , the population genetic diversity will be reduced and the extinction probability will be increased .

不同个体之间近交衰退程度存在明显差异。

The result also showed that , among the individuals , there was obvious difference in degrees of the inbreeding deprssion .

分析表明近交衰退发生在幼苗至成熟之间，也可能在开花与结实期。

Detail analysis suggests that the inbreeding depression might occur during the period of seeding and adult stage or of flowering and seed filled stage .

两种方法均表明该斑节对虾养殖群体的遗传多样性水平较高，但可能已有近交衰退发生。

All these results show that the cultured population of Penaeus monodon in Xiamen has a relatively high genetic diversity , but inbreeding may have occurred .

结果表明由于相关系数较低，不能以家系近交衰退的程度推断其背景回复率的相对高低。

The results show that the correlation coefficient was too low to infer the relative level of PRPG from the degree of inbreeding depression . 4 .

在群体改良方案中，混合选择法既可以保持群体内的遗传变异，又可以防止近交衰退。

Compared with other ways of population improvement , Mass selection can not only preserve genetic variance within populations , but also prevent from inbreeding depression .

此项研究结果，对日后豚鹿人工种群繁殖配对策略与计划的制定，以及基于避免近交衰退而在各饲养单位之间的个体交换，提供了科学的参考依据。

The result of this research will offer scientific references for future reproduction strategy design of captive hog deers and individual exchanges for avoidance of inbreeding between different hog deer raising institutions .

采用电泳数据间接估算的近交衰退程度很高.不同个体之间近交衰退程度存在明显差异。

Calculations from electrophoresis data showed that very a high inbreeding retrogression occurred in the C. The result also showed that , among the individuals , there was obvious difference in degrees of the inbreeding deprssion .

这意味着：我们在以后的理论和实验研究中，度量这些值（集合种群的迁移率、近交衰退和遗传负荷等）要分年龄进行。

This suggests that , in future theoretical and experimental studies , there is the potential need for measuring these values ( migration rate , within-deme inbreeding depression , genetic load etc. ) in demes of different ages .

然而因栖息地的丢失和污染，资源破坏严重，有的种群处于濒危或灭绝状态。在考虑近交衰退的影响后，遗传多样性水平降低，灭绝率提高；

Unfortunately , most of the population are declining with several species even to threatened or endangered due to habitat loss and environment pollution . When considering inbreeding depression , the population genetic diversity will be reduced and the extinction probability will be increased .