四倍的

The autotetraploid plants were obtained by identifying the characteristics of morphology, cytology, agronomy,and nutrition quality.

采用不同质量浓度的秋水仙素处理子叶期二倍体萝卜茎尖生长点，通过对突变株进行形态学、细胞学、农艺学及营养品质鉴定，获得同源四倍体。

In crossing of the 8 autotetraploidy rices (Oryza sativa, 2n=4x=48), APIV(4), IR36(4), Zixuedao(4), Ce 64(4), Minghui 63(4), IR28(4), Ce 90(4) and Gui 99(4) used as the females, with Pennisetum alopecuroides (2n=2x=18) used as the males, the seeds were obtained, but no seed was got in the crosses of the 3 diploidy rices (Oryza sativa, 2n=2x=24), APIV(2), Ce 90(2) and Zixuedao(2) used as the females, with Pennisetum alopecuroides.

利用APIV(4)、IR36(4)、紫血稻(4)、测64(4)、明恢63(4)、IR28(4)、测90(4)和桂99(4)等8个同源四倍体水稻(Oryza sativa， 2n=4x=48)为杂交母本，以狼尾草(Pennisetum alopecuroides， 2n=2x=18)为杂交父本进行杂交，获得了实粒种子。但是，在以APIV(2)、测90(2)和紫血稻(2)这3个二倍体水稻(Oryza sativa， 2n=2x=24)为杂交母本，以狼尾草为杂交父本的杂交组合中却没有获得实粒种子。

It has an unusually high initial modulus of 476 grams per denier. This is about two times greater

凯夫拉纤维具有异乎寻常的高初始模量，其值为476克力／旦尼尔，是玻璃长丝或钢丝的两倍，是工业涤纶丝的四倍，是工业尼龙丝的九倍。

Autotetraploids from diploidy leaves of Paulownia elongata on the double layer MS media supplemented with 0.1 mg/L NAA and 15 mg/L BA(optimal organogenetic medium to the leaves of diploidy seedlings) with different colchicines concentrations were induced,chromosome numbering of the plant root tip cells and DNA content analysis of the leaf single cell were used to analyse the autotetra ploids.

在含不同浓度秋水仙素的MS+0.1mg/L NAA+15mg/L BA双层培养基上进行兰考泡桐四倍体植株诱导试验，并通过变异植株根尖细胞染色体观察和叶片单细胞DNA含量测定进行倍性分析。

The results showed that diploid and tetraploid had higher root activity, flagleaf soluble protein content, SOD and CAT activity before anthesis. However, the rootactivity, flag leaf soluble protein content, SOD and CAT activity of diploid and tetraploiddeclined more quickly and became lower than those of hexaploid species from 15 days afteranthesis. While MDA content increased more quickly and became higher than those ofhexaploid species from 5 days after anthesis. Correlation analysis showed that delaying the flag leaf senescence can promoted transfer of nitrogen and dry matter, increasedaccumulation of nitrogen and dry matter after anthesis, enhanced grain and protein yield.

结果表明，与普通小麦和小黑麦相比，二倍体和四倍体材料开花以前具有比较高的根系活力、可溶性蛋白含量、SOD和CAT活性；开花以后，根系活力、旗叶可溶性蛋白含量、SOD和CAT活性快速下降，MDA含量快速上升，衰老加快；相关分析表明，延缓小麦旗叶衰老进程，可以促进花后氮素和干物质运转，增加花后氮素和干物质积累，提高籽粒产量和籽粒氮素积累量。

There are tetraploid and diploid regenerated plants in "Page tangelo + Valencia orange" and "Hongju tangerine + Rough lemon".

丹西红橘+粗柠檬和佩奇橘柚+伏令夏橙2个组合的再生植株既有二倍体也有四倍体；

Hybridization of diploid and tetraploid is an effective way to breed seedless triploid citrus.

利用二倍体与同源四倍体杂交是培育无核三倍体柑橘的一种有效方法。

Monosomic 3, monosomic 5, monosomic 10, trisomic 4 and trisomic 5 as experiment materials, their meiosis behavior of pollen mother cell, pollen characteristics, physiological and biochemical characteristics of anther, section observation of pollen development and the structure of embryo sac were studied, and the effects on the seed set and transmission rate were analyzed.

本文以大白菜同源四倍体小孢子培养产生的且已鉴定为3号单体、5号单体、10号单体、4号初级三体、5号初级三体的非整倍体株系及二倍体株系等为试材，对各材料的结籽率、雄配子传递率进行了统计，并对花粉母细胞减数分裂行为、花粉特性、花粉发育和胚囊结构以及花药生理生化特性等方面进行了观察研究，进而分析了其对大白菜单体n-1雄配子和三体n+1雄配子传递率的影响。

The article discusses China's economy, port logistics and the developing strategy of ports;explores the transnormal collaboration between Shanghai and Yangshan, and the rise of Jiangshu and Zhejiang Provinces's harbors;as well as analyses how to encourage healthy competition, how to establish reasonable logistic system and effective cooperation mechanisim.

本文对中国经济和港口物流，港口的发展战略，上海和洋山的超常规合作，江浙两省的港口崛起，鼓励健康竞争，建立合理物流体系以及有效合作机制做了探讨和分析。这里专家的回答会让您满意早知道白云兄出手，我就不翻译了，不过，这里说明一下：增长了近3倍，应该是翻了近四倍，而不是三倍。

However, the use of Aegliops tauschii in improvement of wheat yield trait has not been reported. In this study, T.durum-Ae.Squarrosa amphidiploids was crossed with common wheat PH85-16, then backcrossed with PH85-16. The variation characteristic of the main yield traits of BC1F1 and BC1F2 were analyzed. Then, QTLs affecting yield traits were detected by 130 SSR primer pairs of D genome in BC_1F_1 and BC_1F_2.The result showed chromosomes in D genome from Aegliops tauschii affected yield trait of wheat significantly.

本研究以二倍体小麦粗山羊草与四倍体硬粒小麦合成的双二倍体Am6为亲本，与普通小麦PH85-16 进行杂交，再用PH85-16 进行回交，对获得的回交后代进行了主要产量性状调查，利用位于小麦D 基组的SSR 分子标记进行了分子标记分析，对来自粗山羊草与产量性状相关的数量性状位点进行定位，探讨粗山羊草对小麦产量性状的影响。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。