杂种优势的

Apomixis provides a unique opportunity to fix and utilize hybrid vigor. A number of research programs around the world have tried to use apomixis as an important plant-breeding tool.

无融合生殖是指不经过雌雄配子融合而产生种子的一种特殊生殖方式，能使基因型的杂合性得以保持，从而可以固定杂种优势，对作物育种具有极其重要的意义。

Apomixis allows the establishment of genetically stable seed propagating clones of crops,which can perpetuate themselves across countless sporophytic generations.

利用植物无融合生殖固定杂种优势，已被认为是一条生产杂交种子的高效途径。近年来，由于RAPD、RFLP和差异显示等技术的应用，已使植物无融合生殖的研究面貌一新。

The hybrids of CY×WP was found to show the highest heterosis ratewith a range of values from 2.28% to 18.20% on the four growth traits of body length,body weight, cephalothorax length and abdominal length, while the hybrids ofCY×HB and WP×CY showed the poor heterosis among the six hybridizationcombinations.

研究结果表明，在生长性状上，CY×WP组合的子一代无论在形态性状(体长、头胸甲长、腹节长)还是体重均较其它组合表现出最大的杂种优势(2.28％～18.20％)，而CY×HB和WP×CY组合子一代的各生长性状表现出杂交劣势。

The apomictic research progress in plants is summarized, including the approaches of fixing heteroses, selecting and breeding of plant varieties and apomictic materials, embryology, genetics, apomictic characteristics and so on .

介绍了植物无融合生殖在选育无融合生殖品种及育种材料方面的成果；概述了植物无融合生殖在胚胎学、遗传学及生殖特性，杂种优势固定途径及无融合生殖材料选育途径等方面研究的现状和趋势。

Large degree of variation in growth performance and hetercsis were found among different cross combinations of 6×6 diallel cross of Pines massoniana.

马尾松6×6全双列杂交的不同组合，其11年生子代在生长性状及其杂种优势上均存在较大的差异。

Information on the combining ability and heterotic patterns of maize germplasm is of great value to maize breeders.

研究玉米种质的遗传关系及其杂种优势模式对玉米育种者有着极为重要的指导意义。

Huangzaosi inbred lines(Huangzaosi and its derived lines) is recognized as one of five heterotic groups by maize breeding in China. It has characters of high combining ability, ideal plant type, drought and barrent tolerance, wide adaptation and so on.

黄早四种群自交系是我国玉米育种的五大骨干杂种优势类群之一，建立在黄早四及其改良的衍生系基础之上，具有配合力高、株型好、耐旱耐瘠、适应性广等特点。

In this paper, Platycodon grandiflorum was studied to explore the method and technology of using heterosis in sexual reproduction medicinal plant, which is to la.

本论文以我国重要中药材桔梗为对象，探索有性繁殖药用植物杂种优势利用需要解决的关键基础问题，为培育药材专用或药食兼用的优良桔梗杂交品种奠定基础。

Maize (Zea mays L.) is one of the most important crops because of the remarkable properties of its hybrid, which is responsible for the high commercial value of hybrid maize.

杂种优势在提高粮食作物特别是玉米的产量方面具有重要的作用。

Cytoplasm is the environment of gene expression, and mitochondrion provides the energy to support the biochemical reaction.

各个遗传系统，包括核基因组、线粒体基因组以及叶绿体基因组在复杂性状的遗传表达以及杂种优势形成中均可能发挥重要的作用。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。