淤泥湖团头鲂与梁子湖团头鲂杂交子一代的性状研究

团头鲂(Megalobrama amblycephala Yih)是一种优良的淡水养殖鱼类,但在家养条件下连续传代会引起经济性状指标下降。本试验通过原种选优,以优配优的杂交组合,得出淤泥湖团头鲂与梁子湖团头鲂杂交子一代和回交子代。经饲养观察,证明杂交子一代和回交子代都有良好的生长优势,含肉率和粗蛋白含量相对增高,经济性状较亲本更好。血清蛋白电泳分析结果表明,杂交子代与亲本存在着质的差异。     

烟草与罗勒科间远缘杂交育种的研究

利用烟草与药用植物罗勒进行科间远缘杂交,以期培育出含医药成分的新型烟草,以缓解吸烟与健康的矛盾。采用无性与有性杂交相结合的方法,克服其杂交不孕问题。经酶谱测定,杂种稳定品系含有亲本药用植物的遗传物质;镜检(F1~F18)细胞染色体呈杂合状态;经医药成分鉴定均含有药用植物亲本中相应的医药成分,并产生了新的医药成分;烟叶评吸具有药物香气。化学成分测定结果表明,罗勒烟具有低糖,中、高烟碱含量的特点。经卷烟企业验证其可用性,具有较高的应用价值。     

家蚕丝质性状选择效果研究

本文采用系统选择、杂交改良等方法。对解舒、净度、强伸力、茧丝长等家蚕主要丝质性状进行了研究。结果表明,解舒、净度、茧丝长系统选择与杂交改良是有效的;对解舒率和茧丝长进行严格综合系统选择,在一定程度上能克服解舒率与茧丝长的负相关关系;系统选择法所建立的解舒好系与解舒差系能稳定遗传;解舒率与强力、伸长度成正相关,但相关程度很低,一代杂种的强力高于原种。     

Tartary buckwheat breeding (<Emphasis Type="Italic">Fagopyrum tataricum</Emphasis> L. Gaertn.) through hybridization with its Rice-Tartary type

Tartary buckwheat (Fagopyrum tataricum) is a highly nutritious crop that is widely grown in Asia, but the flour contains a large portion of the hull if it is ground with industrial processing since the hull is very hard to remove as it adheres to the testa layer of the groat. Rice-Tartary, a particular type of Tartary buckwheat, has seeds with a loose hull and the presence of splits on the sides of the seeds that make dehulling easily. The present study reports on the first attempt of crop improvement in Tartary buckwheat breeding through hybridization. Hybrids were obtained by hybridization of crosses between Tartary buckwheat and Rice-Tartary. Additional crosses were made among selected progenies of these crosses. Based on progeny analysis of the F₁, F₂, and F₃, the character of Rice-Tartary, as exhibited as the presence of splits on the sides of the seeds, is controlled by one gene which is homozygous recessive. A Tartary buckwheat breeding program has been conducted for 6 years based on these crosses. Advanced lines with easy dehull and yield potential are at the stage of ready for yield trials. Production of easy dehulling Tartary buckwheat in the future could boost Canada’s domestic and international markets.     

核不育油用亚麻开花习性与杂交技术研究

核不育油用亚麻的开花习性与普通亚麻基本相同.其开花数与开花所需日数与气候条件和植株分枝多少有关,且比可育株为多.亚麻不育株与可育株的开花顺序相似,均自上而下,由里向外交替开放,各分枝的小分枝也是如此.晴朗的高温低湿天气,清晨5—6时开始开花,8时左右花全开,15时左右花才凋谢.而在低温高湿天气,不育株花的开花与凋谢时间推后.核不育亚麻的柱头生活力可以维持3—4天,以开花当天与次日的生活力最强,结实率最高,故配置杂交组合应在开花当天或次日进行,结实效果最好.花粉生活力的强弱,与温度高低也有关,在低温或冷凉条件下保存花粉,寿命最长,高温下保存的则较短.核不育亚麻作异交后,能分离出约占一半的不育株.其异交结实率的高低,将关系到育种工作的成效及杂种优势的利用.     

Hatchery introgression blurs ancient hybridization between brown trout (Salmo trutta) lineages as indicated by complementary allozymes and mtDNA markers

Populations living on the periphery of a species range are subjected to intense habitat pressures that stress their vulnerability to threats. South Iberian brown trout (Salmo trutta) populations are located on the southwestern boundary of the species range in Europe. This region has been described as a contact zone between Atlantic and Mediterranean populations in other fish species, and allozyme data detected natural hybridization between native Atlantic and Mediterranean brown trout in this area. Nevertheless, native pattern of populations relationships are threatened by hybridization with exogenous hatchery fish. Allozyme data and complete mtDNA control region sequences were used to analyse the ongoing processes of human mediated hybridization between native and hatchery brown trout in this region. Estimates of the persistence of hatchery genes detected a high level of introgression in some of the sampled locations (hatchery ancestry more than 25% in GF-1, GF-2 and GF-3), but results differed from both kinds of markers. The low intrapopulation diversity (H_s = 0.051) indicated that genetic drift could explain discrepancies between markers. At individual level, the complementary use of both markers detected more hatchery origin fish than those detected by the use of a single technique. Based on these results, the importance of considering a large number of genetic markers to evaluate introgression accurately is emphasized. The ability of the current management policies to the protection and conservation of marginal populations that retain complex and special evolutionary histories such as those studied is also questioned.     

同源四倍体矮脚黄白菜与芸苔属作物杂交的亲和性

以选育的同源四倍体矮脚黄白菜为母本,选用其亲本二倍体矮脚黄及其它白菜品种,以及大白菜、甘蓝、甘蓝型海莱、芥菜等为父本,分别进行人工杂交,所得F_1种子中的杂株率有差异:二倍体矮脚黄为父本的是1.7％,其反交为6％;黑心乌白菜和甘蓝为父本的都是0;而芥菜和甘蓝型油为菜父本的分别是31％和36％。但是统计其杂种指数,则皆小于1,表现杂交不亲和。 连续三年调查了同源四倍体矮脚黄自然授粉采种的杂株率,平均为0.59％,但杂株中又以芥型和甘蓝油菜型较多,平均占65.0％和22.5％;而二倍体矮脚黄在同样条件下却高达16.5％。由此可见,同源四倍体矮脚黄在留生产种时,只需与芥菜和甘蓝型油菜隔离即可。     

Effects of dietary sodium on the expression of angiotensinogen mRNA in myocardium of rats with congestive heart failure

AIM:This study was designed to investigate the effects of sodium restriction and sodium supplementation on the expression of angiotensinogen mRNA in myocardium of rats with congestive heart failure(CHF).METHODS:Radioimmunassay and in situ hybridization techniques were used to determine the angiotensin Ⅱ(AngⅡ)contents and the expression of angiotensinogen(ANG)mRNA in myocardium, respectively.RESULTS: In sodium restricted group, the plasma sodium was obviously lower than that in CHF group(P＜0.05), while the contents of AngⅡ,the expression of ANG mRNA in myocardium and the ratio of heart weight/body weight(HW/BW)were significantly higher than those in CHF group (P＜0.05 or P＜0.01). It was also found that the AngⅡ, the mRNA contents in rat myocardium and the ratio of HW/BW were not significantly changed in case of sodium supplementation. CONCLUSION:Restriction of sodium intake can further activate the local renin-angiotensin system in CHF heart.     

刺槐开花传粉及交配方式

在北京延庆县观测刺槐花朵的形态特征、开花动态以及传粉媒介,用杂交指数(OC,I)、花粉—胚珠比(P/O)、人工授粉等方法分别测定刺槐的交配方式。结果表明,刺槐为两性花,有10个雄蕊,且分布在雌蕊周围,柱头比花药最多高出(4.53±0.11)mm,雌雄蕊同熟;单花花粉量高达28 071.67±879.47,花粉保存1 d后有活力的占87.67%,花粉胚珠比(P/O)高于1 000;雌蕊的可授期从开花前2 d持续到开花后2 d,共持续4 d左右,超出这一阶段,可授性大大下降;刺槐杂交指数(OC,I)为4,授粉试验结果表明天然授粉坐果率最高,其均值为40.67%,套袋自交平均坐果率18.0%,去雄杂交平均坐果率3.56%。刺槐属于异交为主、部分自交亲和的交配方式,异花授粉方式为虫媒传粉。     

10份彩色马铃薯亲本材料的杂交效果分析

[目的]对引进的10份彩色马铃薯(Solanum tuberosum)亲本材料进行杂交组配,以确定其在杂交育种中的利用价值。[方法]试验材料种植在塑料大棚内,母本在07:00～11:00、16:00～18:00去雄。授粉于08:00～11:00进行,授粉后标明组合名称、日期及授粉花数。浆果成熟后统计浆果数及种子数。[结果]10份彩色马铃薯亲本材料均可在杂交育种中直接利用。AC0106、AC0131、紫云1号、AC0324、AC0391等宜作母本利用,其中,紫云1号作母本,平均坐果率48.8%,平均单果种子数76粒;AC1079、AC0338、AC0082、AC0849、AC0099作父本时有较高的组合成功率和坐果率,单果种子数亦较多,较之其作母本有较强的优势。其中,AC0082作父本,平均坐果率65.0%,平均单果种子数128粒。[结论]该研究可为10份彩色马铃薯在杂交育种中的利用提供科学依据。