家蚕成虫雌雄差异的基因表达分析

研究家蚕成虫雌雄差异的基因表达,可为探究家蚕以及鳞翅目昆虫雌雄差异的分子机制提供线索。利用家蚕全基因组芯片检测家蚕成虫雌雄差异基因表达谱,并采用聚类及功能注释对芯片检测结果进行分析。结果显示有11677个基因在家蚕成虫中表达,其中有3312个基因在雄性个体表达上调,4254个在雌性个体表达上调。雌雄个体中表达上调基因的GO分类比较显示这2类基因在分子伴侣调控、电子载体等功能方面差异较大。在雌雄差异基因的功能注释中发现了与性腺特异性、发育繁殖及选择拼接因子等相关的基因。家蚕成虫存在的与雌雄个体特异相关的差异表达基因,可作为家蚕雌雄个体性别相关的生物遗传学标志。     

放牧对冷蒿繁殖特性的影响

重度放牧对冷蒿(Artemisia frigida)的有性生殖具有严重的阻碍作用,严重影响其有性生殖;冷蒿生殖枝分化率、生殖枝花序数、种子产量、种子成熟度和发芽率之间在同一牧压下表现并不一致,在不同牧压下存在一定的平衡关系;放牧强度起调节作用是冷蒿对放牧的适应机制.     

龙甜雪冠甜瓜的选育

龙甜雪冠是由灰艮皮中白皮变异株系H4 8和龙甜 1号中白皮变异株系L3杂交选育而成的早熟薄皮甜瓜 ,生育期 62～ 65d(天 ) ,抗枯萎病。果实近圆形 ,白皮 ,可溶性固形物含量12 .58% ,品质佳。平均单瓜质量 0 .55kg ,果实商品性状好 ,每 667m2 产量 2 50 0～ 2 90 0kg。     

沙棘的花芽分化及花器发育进程研究

利用光学显微镜对中国沙棘花芽分化及花器发育进程进行观察研究,结果表明:沙棘花芽分化分为花芽分化开始期、花序分化期、花蕾分化期、花萼分化期、雄蕊分化期、雌蕊分化期。花粉性细胞的发育经过花粉母细胞、二分体、四分休、单核花粉粒、双核花粉粒几个阶段。胚囊发育包括孢原阶段、四分孢子、经减数分裂,形成成熟胚囊等几个阶段。该研究为合理制定沙棘的栽培技术措施和培育新品种提供了科学依据。     

现代百合品种培育的技术途径及其杂交特殊现象的机制

为了减少百合(Lilium)育种的盲目性,提高育种效率,本文主要以作者在百合育种工作中的结果和经验为基础,对现代百合品种与野生种的关系、百合组内杂交和组间杂交的差异、现代百合品种的育种途径、非整倍体百合的培育以及百合杂交中特殊现象的机制与新假说(即:百合倍性间杂交的胚乳中含有5个或以上相同基因组是其发育和杂交成功之关键)等方面进行了概述,为百合育种工作者提供有益的参考资料。     

鼠尾藻的有性繁殖过程和幼苗培育技术研究

重点研究了鼠尾藻的有性繁殖特性和规律,系统观察了鼠尾藻的成熟季节,雌、雄生殖托的成熟、排卵、排精、受精卵的细胞分裂、假根的形成、幼孢子体的构建和生长特征。并在实验室进行采苗和苗种培育试验,获得理想结果,该培育技术可以应用到生产中。     

Long photoperiod delayed spawning and increased somatic growth in gilthead seabream (Sparus aurata)

The effects of extended photoperiods, mimicking the longest day of the year, were studied in 1- and 2-year seabream. The photoperiod regimes started in late July, 36 and 39 days after the summer solstice and continued for 11 months, well beyond the natural reproductive season of December–March. Regime 1 (long day, 15.5L:8.5D), which used natural and fluorescent light, reduced the incidence of maturity in both year classes and females did not spawn although some gonadal development was observed. Among all 1-year sampled fish of regime 1, a maximum of 5% became spermiating males (March) and 5% reached the yolk granule stage of vitellogenesis (VO3; 250–400 μm diameter) by May. Among 2-year sampled fish of regime 1, 45% became spermiating males and 25% were females, which reached the advanced vitellogenesis stage (VO4; 400–600 μm) by April. Regime 2 (skeleton photoperiod), consisting of natural light and a 1.5-h pulse of fluorescent light during the period 14–15.5 h after sunrise, postponed gonadal development and spawning for up to 3 months. In this regime, a maximum of 80% of 1-year sampled fish were spermiating males in February and a maximum of 10% were VO3 stage females in March. In the sampled 2-year fish, the maximum levels were 50% spermiating males in February and 25% VO3 stage females in March. Control fish, which were exposed to the natural photoperiod (29°34′N), spawned during their natural season. The maximum levels for 1-year sampled control fish were 95% spermiating males and no females in December, while among 2-year sampled fish, maxima of 75% males in February and 45% VO4 stage females in November. Final average weights of photoperiod treated fish (1-year=430 g—regime 1, 400 g—regime 2; 2-year=582 g—regime 1, 518 g—regime 2) were significantly greater (p<0.05) than control fish (1-year=341 g; 2-year=476 g). Daily feed consumption (g/100 g fish) dropped from an average of 1.83 to 0.93 g for 1-year fish during August–December and from 0.88 to 0.54 g for 2-year fish during the same period. This was correlated with reduced autumn and winter water temperatures (26–20°C summer to winter change) and increased fish weight in all treatments. Daily feed consumption was also affected by the onset of spawning in the control and regime 2 (skeleton photoperiod) treatments of both 1- and 2-year fish. The efficiency of feed utilization (FCR) and protein and energy retention were all affected by the photoperiod regimes and followed the same pattern of decrease as weight gain, regime 1 (long day)>regime 2 (skeleton photoperiod)>control.     

恶疫霉有性生殖交配行为的研究

 对同宗配合疫霉种——恶疫霉(Phytophthora cactorum Schroter)抗甲霜灵突变株和抗地茂散突变株的抗药性在游动孢子和卵孢子后代的遗传分析,筛选到抗性分别由细胞核纯合显性单基因控制的抗甲霜灵突变株和由细胞质可稳定遗传的线粒体基因控制的抗地茂散突变株。将携带抗甲霜灵对地茂散敏感(即Mt^rCn^s)标记的亲本与携带抗地茂散对甲霜灵敏感(即Mt^sCn^r)标记的亲本共同培养,在200个有性生殖单卵孢后代中检测到携带3种不同抗药性标记的单孢株,其中32株携带Mt^rCn^s标记,165株携带Mt^sCn^r标记,另有3株同时携带双亲的标记性状即MtrCnr。结果表明:恶疫霉种内不同菌株共同培养时,有性生殖以配对亲本的各自自交为主,同时配对亲本间也可发生一定频率的杂交。     

出雏不同阶段公母雏鸡性比的探讨

本试验利用七批种蛋的孵化出雏,观察统计了55635只初生雏的性别情况。结果表明,出雏不同阶段的公母雏鸡性比存在着极显著的差异,这种差异表现在20天12小时以前出雏的鸡,公鸡比母鸡少,20天12小时以后出雏的鸡,公鸡比母鸡多,特别是20天22小时后,公鸡比母鸡多50％以上。