皱纹盘鲍（Haliotis discus hannai）、黑足鲍（Haliotis iris）及其杂交F1代营养成分的比较分析

利用生物化学方法,对皱纹盘鲍、黑足鲍及其杂交F1腹足部肌肉一般营养成分、氨基酸及脂肪酸组成与含量、矿物质元素及总糖和还原糖含量进行测定分析。结果表明,杂交鲍的粗蛋白含量最高（17．97％）,黑足鲍的粗脂（1％）和粗糖（9．29％）含量最高;杂交鲍氨基酸总含量（58．91％）和呈味氨基酸含量（28．77％）最高,黑足鲍的必需氨基酸含量最高（21．33％）,皱纹盘鲍氨基酸总含量、呈味氨基酸含量及必需氨基酸含量最低;黑足鲍与杂交鲍脂肪酸种类和不饱和脂肪酸含量高于皱纹盘鲍。实验共测定9种矿物质元素,除了黑足鲍腹足部肌肉Mn、Cu含量明显高于皱纹盘鲍和杂交鲍外,3种鲍其他7种矿物质元素含量差别不大;黑足鲍总糖和还原糖含量最高,皱纹盘鲍最低。以上实验结果表明,通过种间杂交,亲本某些遗传性状缺陷在子代中得以改良,并且获得的杂交F1代部分性状优于双亲,表现出一定的杂交优势。     

杂色鲍×盘鲍杂交及亲本自繁群体的AFLP分析

应用AFLP技术研究了杂色鲍(SS)、盘鲍(JJ)及其正反交群体(SJ和JS)的遗传关系,并比较了各群体内的遗传多样性.3对选择性引物共扩增出344个位点.双亲自繁群体SS和JJ 的AFLP图谱差异很大,平均遗传距离达1.425.因此,AFLP图谱可以用于两物种及其杂交种的种质鉴别.正反交群体SJ与JS的AFLP图谱很接近于母本自繁群体,平均遗传距离分别为0.111(SJ与SS之间)和0.134(JS与JJ之间),而与父本自繁群体则有较大区别,平均遗传距离分别达1.408(SJ与JJ之间)和1.394(JS与SS之间).将4个群体分为SS/SJ和JS/JJ两组,进行三水平的AMOVA分析,结果显示:84.74%遗传变异来源于母本不同的两组之间(SS/SJ组和JS/JJ组之间),12.66%变异存在于群体内个体之间,正反交群体与母本之间的变异仅有2.60%.另一方面,正反交F_1群体的多态性位点比例、Nei′s 遗传多样度、香农多样性指数均低于母本自繁群体.综合群体内多样性和群体间遗传关系分析结果,杂色鲍与盘鲍正反交F_1的遗传物质组成有别于同时含有双亲基因组的实质性杂交,而与母本有着高度的遗传同质性,且遗传多样性水平略低于母本自繁群体.     

皱纹盘鲍（Haliotis discus hannai）、黑足鲍（Haliotis iris）及其杂交F1代同工酶比较分析

采用垂直板聚丙烯酰胺凝胶电泳技术,对皱纹盘鲍、黑足鲍及其杂交F1代的脏器和肌肉中的7种同工酶（ MDH、POD、EST、CAT、ODH、SOD和LDH）进行了比较分析,以探究双亲同工酶基因在杂交F1代中的表达情况以及3种鲍鱼品系之间产生差异的分子基础。结果表明,两亲本中部分同工酶谱表达相似,如ODH和肌肉中的POD、EST在父母本中酶谱相同;同时两个亲本之间的同工酶谱具有差别,MDH、LDH和内脏中EST的酶谱均存在稳定的种间差异。杂交F1代的同工酶谱与母本皱纹盘鲍的相似,其中POD、EST、LDH、SOD和肌肉中的MDH酶谱均与母本相同,而与父本黑足鲍的差别较大,说明主要是母本的同工酶基因在杂交F1代中表达。     

皱纹盘鲍杂交群体与自然种群遗传差异的研究

利用RAPD技术对皱纹盘鲍自然种群和杂交养殖群体进行了遗传差异分析,共检测到173个位点．在自然种群和杂交群体之间及两个杂交群体之间都存在差异,并得到一些群体的特异性片段．利用PopGen32软件计算了各个群体的多态位点比例、平均遗传杂合度、Shannon多态性指数和群体问的遗传距离．结果表明,杂交群体的遗传多样性高于自然群体,从遗传多样性角度揭示了皱纹盘鲍杂种优势的存在．     

草鱼、赤眼鳟及其杂交F_1的形态差异分析

为了研究正交F1(草鱼♀×赤眼鳟♂)、反交F1(赤眼鳟♀×草鱼♂)的形态特点,采用传统形态学测定与现代框架测定结合的方法,测定了杂交F1及其亲本的可量可数性状,并进行了相关统计分析。结果显示:草鱼、赤眼鳟及正、反交F1在体型、体色、眼睛、鳞片以及口须等性状上有差异;杂交F1的胸鳍分支鳍条、侧线鳞数、侧线下鳞数与赤眼鳟差异显著(P0.05);正交F1的体宽超亲本偏离,反交F1的吻长、口长、口裂长、眼间距、尾鳍长超亲本偏离;聚类结果表明杂种F1的传统可量性状偏赤眼鳟遗传,框架性状偏草鱼遗传;构建了4个群体的判别函数,其判别准确率均为100%。综上所述,杂交F1综合了双亲特点,且存在杂种优势性状,可考虑作为新品种开发。     

Genetic basis of heterosis and inbreeding depression in rice （Oryza sativa L.）

The genetic basis of heterosis was studied through mid-parent, standard variety and better parent for 11 quantitative traits in 17 parental lines and their 10 selected hybrids in rice (Oryza sativa L.). The characters were plant height, days to flag leaf initiation, days to first panicle initiation, days to 100% flowering, panicle length, flag leaf length, days to maturity, number of fertile spikelet/panicle, number of effective tillers/hill, grain yield/10-hill, and 1000-grain weight. In general the hybrids performed significantly better than the respective parents. Significant heterosis was observed for most of the studied characters. Among the 10 hybrids, four hybrids viz., 17Ax45R, 25Ax37R, 27Ax39R, 31Ax47R, and 35Ax47R showed highest heterosis in 10-hill grain yield/10-hill. Inbreeding depression of F2 progeny was also studied for 11 characters of 10 hybrids. Both positive and negative inbreeding depression were found in many crosses for the studied characters, but none was found significant. Selection of good parents was found to be the most important for developing high yielding hybrid rice varieties.     

陆地棉显性无腺体品系与常规品种间杂种优势利用研究 Ⅲ.杂种优势及其与配合力的相关

以７个显性无腺体陆地棉品系和４个常规品种为材料,按ＮＣⅡ设计,对２８个组合的Ｆ１杂种优势及其与配合力的相关进行了分析。结果表明：杂种Ｆ１具有明显优势,２８个组合所研究的１５个性状全部具有中亲优势,６个性状具有高亲优势,４个性状具有竞争优势;杂种Ｆ１各性状的竞争优势分别与父本、母本一般配合力效应值,父母本一般配合力效应平均值和组合特殊配合力效应值均有不同程度的相关,而以父母本一般配合力效应平均值与竞争优势的相关最密切且稳定。     

Comparative growth and viability of hybrids between two populations of Chinese shrimp （Fennropenaeus chinensis）

The total yield of shrimp farming industry declined after WSSV broke out. It was only at the last 20 years that production had again begun to increase[1]. So far, shrimp farming industries mostly depend on capturing wild shrimps or wild post-larvae to sto…     

The relationship of differential expression of genes in GA biosynthesis and response pathways with heterosis of plant height in a wheat diallel cross

Heterosis in internode elongation and plant height is commonly observed in hybrid plants, but the molecular basis for the increased internode elongation in hybrids is unknown. In this study, midparent heterosis in plant height was determined in a wheat diallel cross involving 16 hybrids and 8 parents, and real-time PCR was used to analyze alterations in gene expression between hybrids and parents. Significant heterosis of plant height and the first internode in length were observed for all 16 hybrids, but the magnitude of heterosis was variable for different cross combinations. Analysis revealed that the heterosis of the first internode was significantly correlated to that of plant height （r = 0.56, P 〈 0.05）, suggesting that the increased elongation of the first internode is the major contributor to the heterosis in plant height. Real-time PCR analysis exhibited that significant difference in heterosis of gene ex- pression was observed among all cross combinations. Moreover, heterosis of the first internode in length was correlated significantly and positively with expression heterosis of KS, GA3ox2-1, GA20ox2, GA20ox1D, GA-MYB and GID1-1, but significantly and negatively with expression heterosis of GAI and GA2ox-1, which is consistent with our recently proposed model of GAs and heterosis in wheat plant height, suggesting the alteration of GA biosynthesis and response pathways might be responsible for the observed heterosis in plant height.     

皱纹盘鲍消化系统的组织学研究

利用光学显微镜研究了皱纹盘鲍的消化系统的组织学结构。结果表明：鲍的消化系统是由消化道（口区、食道、嗉囊、胃盲囊、胃、肠、直肠、肛门）、消化腺（肝胰腺）组成。鲍的唇上皮由单层柱状细胞构成,细胞内充满着色素颗粒,唇内有纵横交错的肌纤维,其间有许多神经纤维分布。其齿舌比较发达,齿舌囊的腹面正中线及其两侧分别有极发达的横纹肌肉块。两侧的肌肉与包围齿舌软骨的肌肉群相汇合,其中绝大部分为纵肌,亦有少量环肌或斜     

黄瓜亲本间分子遗传距离与杂种优势的相关性

选用10个黄瓜亲本,通过RAPD分析计算其分子遗传距离,然后配制遗传距离大,中,小的杂交组合15个,田间测定它们的16个园艺性状,对所得园艺性状数据进行统计分析,并计算园艺性状与分子遗传距离间各种相关曲线的相关系数,结果发现,黄瓜园艺性状与分子遗传距离间的各种相关曲线中,以抛物线的相关系数最优,其中座瓜率,收获始期与分子遗传距离的抛物线相关系数存在着显著相关性。     

Primary analysis of QTG contribution to heterosis in upland cotton

In this paper, we analyzed the contribution of pure DNA factors to heterosis using quantitative trait genes (QTG) in two randomly selected strains from a recombinant inbred line of Gossypium hirsutum. According to a set of QTL mapping results, combined with analysis of DNA recombinant fragment sources in the two strains and QTL association analysis with their field traits, we hypothesize a view of “dominance + overdominance + epistasis”. That is, additive and additive epistasis may be the genetic basis of heterosis, and dominance, overdominance and epistasis may be the modes of heterosis action. Based on the heterosis results of this study, we also suggest a molecular mechanism for heterosis, and explain, in detail, with two randomly selected strains as examples. The male and female parent-derived additive epistatic QTLs of upper half mean length in LG01 and LG03 produced a trait variance of 2.99–3.52 compared with the female parent-derived loci. The trait of bolls per plant was controlled by two pairs of additive epistatic QTLs in LG02 and LG07, which were derived from both female and male parents. The QTLs were reciprocally interacted and produced a trait variance of 0.86. An initial concept of “super-hybrid cotton” was raised according to the nature of additive effect, that is genetic stability.     

Relationships between D1 protein, xanthophyll cycle and photodamage-resistant capacity in rice (Orysa sativa L.)

Relationships between D1 protein, xanthophyll cycle and subspecific difference of photodamage-resistant capacity have been studied in O. japonica rice varieties 02428 and 029 (photoinhibition-tolerance) and O. indica rice varieties 3037 and Palghar (photoinhibition-sensitivity) and their reciprocal cross F1 hybrids after photoinhibitory treatment. It was shown that PSⅡ photochemical efficiency (Fv /Fm) decreased, and xanthophyll cycle from violaxanthin (V), via anaxanthin (A), to zeaxanthin (Z) was enhanced and non-photochemical quenching (qN) increased accordingly in SM-pretreated leaves of rice when the synthesis of D1 protein was inhibited, and that there was a decrease in qN and, as a result, more loss of D1 protein and a big decrease in Fv /Fm in DTT-pretreated leaves when xanthophyll cycle was inhibited. O. japonica subspecies had a higher maintaining capacity of D1 protein and a decrease of Fv /Fm in a more narrow range, and exhibited more resistance against photodamage, as compared with O. indica subspecies. The above physiological indexes in reciprocal cross F1 hybrids, though between the values of their parents, were closer to maternal lines than to paternal lines. Experimental results support the concept that the turnover capacity for D1 protein is an important physiological basis of photoinhibition-tolerance, and will provide the physiological basis for selection of the photoinhibition-tolerant parents and develop a new approach to breed hybrids with high photosynthetic efficiency.     

对棉花三系在配制杂种中应用价值的研究

将五个陆地棉恢复系和三个雄性不育系进行杂交，得到１５个杂种Ｆ１；并对杂种Ｆ１的重要农艺性状及纤维品质进行了研究．对试验数据的方差分析表明：有关铃重、衣分、纤维长度和整齐度方面杂种Ｆ１间的差异达到极显著的水平，而在皮棉产量、单株吐絮铃数上的差异却是不显著的．不育系中Ａ和ＰＡ在铃重、衣分和绒长上的一般配合力是高度显著的．恢复系４Ｒ—１６在铃重、衣分和纤维整齐度的一般配合力也都达到了极显著的水平．这些试验结果对以后的研究和选育强优杂种是有用的。     

皱纹盘鲍循环系统和排泄系统的组织学研究

对皱纹盘鲍的循环系统和排泄系统进行了组织学研究，并对二者组织学上的关系进行了探讨．结果表明：鲍循环系统由心脏、血管和许多血窦组成．属于开管式循环．血液由血浆和3种不同形态的血淋巴细胞构成．鲍的排泄系统主要由左右2个肾脏组成．肾脏呈囊状．由肾脏壁和肾实质构成．而肾脏壁由围心腔壁延伸而成．与围心腔壁具有几乎相同的结构．肾小管是肾实质的主耍功能结构，由一层腺上皮细胞构成．肾小管之间充满血窦．循环系统与排泄系统组织结构上的紧密联系有利于代谢产物的排泄．     

麦饭石、稀土作为鲤鱼、皱纹盘鲍饲料添加剂研究

以麦饭石、麦饭石稀土作为鲤鱼、皱纹盘饱饲料中微量元素添加剂,与无机盐添加剂进行了对比喂养试验。结果表明：饲料中添加1％麦饭石能显著地促进鲤鱼和皱纹盘鲍幼鲍的生长;方差分析表明,在鲤鱼饲料中添加麦饭石的三个试验组鱼体平均增重率与无机盐对照组差异显著（P＜0．05）,与未添加微量元素添加剂的基础组差异极显著（P＜0．01）。皱纹盘鲍饲料中添加1％麦饭石的试验组鲍体平均增重率与无机盐对照组差异不显著,但与未添加微量元素的基础组差异显著（P＜0．05）。     

Cloning of a down-regulated gene encoding small GTP binding protein in hybrid wheat

Previous studies showed that differential gene expression between wheathybrids and their parents was responsible for the heterosis. To provide an insight into the molecular basis of wheat heterosis, one cDNA, designated TaRab, was identified from the cDNA library of wheat seedling leaves. The sequence comparison in GenBank revealed that TaRab is homologous to a group of genes encoding Rab-GTP binding protein. Semi-quantitative RT-PCR analysis indicated that TaRab was expressed in all plant tissues examined, but at slightly higher level in leaves. Further analysis exhibited that TaRab displayed lower expression in hybrid than in its patents in both roots and leaves, which was in agreement with the original results of suppression subtractive hybridization. TaRab was located on chromosome 7B and C-7DS5-0.36 by in silico mapping. The relationship between differential expression of TaRab and the molecular basis of wheat heterosis was also discussed.     

Bt/CpTI抗虫转基因水稻及其非转基因亲本与普通野生稻杂种F2群体的等位基因偏态分离

了解水稻转基因是否影响野生稻基因传递的频率,对于评价转基因逃逸及其生态影响有重要意义.本研究构建了不含转基因和含转基因的栽培稻与普通野生稻杂种F2群体,利用分子标记检测了F2群体各位点的基因型和基因频率.以连续卡方分析了F2群体相关位点的基因型和基因频率观察值是否符合理论分离比,同时对各位点进行了连锁不平衡分析,并对实验群体所需的最小样本量进行理论探索.结果表明两个F2群体分别有25.93%与33.33%的位点出现了显著的非随机分离,非转基因与转基因F2群体分别在偏态分离位点数与偏离亲本方向上出现一定差异,并观察到连锁不平衡位点.实验个体数应不少于280个才能保证实验结果准确.外源转基因在杂种后代群体中会因为选择而影响基因分离,进而影响杂种群体的进化潜力.     

Relationship between differ- ential gene expression pat- terns in functional leaves of maize (Zea mays L.) at milk filling stage and heterosis using cDNA-AFLP

The genetic mechanism of heterosis has been one of the most challenging subjects in life science since the 20th century. However, because of the complexity of its genetic basis and the limitations of research methods and means, there was no substantial progress in the research of heterosis from the beginning of the 20th century to the 1990s. The development in molecular biology and bio- technology, especially that in quantitative trait loci (QTL) mapping methods, has made it possible to resea…     

三种鲍腹足肌胶原多肽抗氧化性研究

研究了皱纹盘鲍(Haliotis discus hannai)、黑足鲍(Haliotis iris)及其杂交鲍腹足胶原多肽的制备和性质,并采用总还原力、对O^-₂·和·OH自由基清除率和致衰小鼠灌胃胶原多肽后体内MDA、SOD和GSH-PX变化来评价3种鲍胶原多肽的抗氧化性。结果显示,皱纹盘鲍、黑足鲍及其杂交鲍的胶原蛋白分别占总蛋白含量的23.44%、30.78%和26.92%,皱纹盘鲍与杂交鲍胶原蛋白含有α1、α2、β和γ链,而黑足鲍胶原蛋白没有γ链;来自3种鲍的胶原多肽均呈现出较高的还原力、O^-₂·和·OH自由基清除能力,对O^-₂·清除率的IC₅₀值分别为3.03、2.40、1.15 g/L,对·OH清除率的IC₅₀值分别为4.12、3.58、3.70 g/L;灌胃3种胶原多肽后,致衰小鼠肝脏和血清的MDA含量均降低,SOD和GSH-PX活力均上升。三者比较,杂交鲍胶原多肽在降低MDA含量、提高GSH-PX活力的作用最强,黑足鲍胶原多肽在提高SOD活力的效果最显著。