无性交

The internal cause includes polarity variation , inbred variation , instability of hybridization and gene mutation . The external cause includes unfitting culture conditions , strain ag ing , unsuitable preservation and infection virus of asexuality propagation .

内因主要包括极性发生变异，自交产生的变异，杂交种性不稳定和基因突变；外因主要包括培养条件不适宜，菌种老化，菌种保藏不当和菌株无性繁殖体感染病毒。

But the Hymen that has a few woman is very withy, and springiness, although via making love for many times also not burst, it is Hymen aperture increases merely just, till somebody bears the Hymen when the first embryo to just appear burst, form Hymen mark, say so, sheet sees red or whether Hymen is complete after marriage anew will judge a female to whether have asexuality life history is not quite accurate also.

但有少数女性的处女膜非常柔韧，并富于弹性，虽经多次性交也不破裂，仅仅是处女膜孔增大而已，有人直至生育第一胎时处女膜才出现破裂，形成处女膜痕，所以说，单从新婚后是否见红或处女膜是否完整来判断一个女性是否有无性生活史也不够准确。

A it is predominantly derived from the initial variety or from a variety which itself was predominantly derived from the initial variety, while retaining the expression of essential characteristics that result from the genotype or combination of genotypes of the initial variety; an essentially derived variety may have been obtained by the selection of a natural or induced mutant or of a somaclonal variant, by the selection of a variant individual from plants of the initial variety, by backcrossing, by a transformation by genetic engineering, or by any other similar method

一个品种主要由原始品种演化而来，或主要由原始品种的实质性派生品种演化而来，同时保留了来自原始品种基因型或基因型组合的基本特征的表达；一个实质性派生品种可能通过选择自然变异或诱变或体细胞无性变异、原始品种植株的个体变异的选择、回交、基因工程的改造或任何其它类似方法而获得。

The establishment of polyploids is favored by differential niche preference, low dispersal, a selfing or asexual mating system, high fecundity , and a perennial life history .

对不同生态位的偏好，低分散，一个自交或无性交配系统，繁殖力高和多年的生活史都有利于多倍体的建立。

The genetic study suggested that the carbendazim-resistance in these mutants could be steadily inherited by asexual and selfed reproduction, and the resistance was controlled by the same single major gene both in laboratory mutants and field resistant isolates, the different levels of resistance or the same resistant level in different strains maybe conferred by mutations at different sites or one site with different allelic mutations. The gene compensates for the sensitivity to MDPC was allelic to that governs the carbendazim resistance, but the mutation for increasing sensitivity to MDPC in this gene could get the pathogen highly resistant to carbendazim.

抗药性遗传研究表明，在所研究的抗药突变体中，抗药性在自交和无性繁殖后代中能稳定遗传；室內抗药突变体和田间抗药菌株对多菌灵的抗药性由同一个主效基因控制，但它们发生突变的位点不同或者同一碱基位点发生了不同的突变；对MDPC的敏感性也是由单个基因控制的，该基因与控制多菌灵抗性的基因是等位基因，当该基因发生对MDPC的敏感性增加的突变时会使病菌对多菌灵产生高水平抗性。

In a design of square,regressive and orthogonal rotation with five factors,a field trial was conducted using Toona sinensis.This sdudy was undertaken to investigate the effects of gibberellic acid(GA3), 6-benzy laminopurine, thiourea C.P.(NH2 2CS, Zinc Sulphate(ZnSO4), sa!tpeter(KNO3) for stratification on the dormancy-breaking of Toona sinensis,and to explore a more effective dormancy-breaking method and its mechanism.

本研究以一、二年生的无性繁殖红香椿苗为材料，采用五因素二次正交旋转组合设计，综合定量地研究6—BA、GA_3、硫脲、ZnSO_4、KNO_3五种化学药剂及其组合对香椿休眠解除的影响及其机理进行研究，并探讨更为有效的打破香椿休眠的方法。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。