烟草主要农艺性状的杂种优势及亲子关系分析

 通过对25个杂种F₁,7个农艺性状优势指数分析知:烟草杂种F₁不仅具有中亲遗传现象,也存在正负杂种优势,杂优大小顺序是叶数、腰叶长宽比、株高、节距、茎粗、叶宽、叶长;亲子相关分析知杂种F₁株高、节距、叶数、叶长宽比与双亲值正相关,与中亲值正相关,与双亲差异无关,而其余性状双亲对F₁效应方向不一致,F₁与双亲差异负相关;叶片有柄对无柄、小叶耳对大叶耳、心脏形对椭园形为显性;为杂种优势利用提供遗传信息。     

陆地棉品种间杂交种鄂杂棉3号正反交后代产量性状研究

以陆地棉品种间杂交种鄂杂棉3号为材料研究产量性状,结果表明:①鄂杂棉3号杂种F1代皮棉产量比对照增产极显著,杂种F2代虽然优势程度有所下降,但与对照相比仍增产显著,且与亲本比较杂种后代增产达显著水平,均表现出增产效应。②鄂杂棉3号杂种后代皮棉产量的增加主要是由于单铃重的增加,其次是衣分。③明确了鄂杂棉3号F2代生产利用的产量优势,且能采取正反交法杂交制种,并初步探讨了强优势组合的亲本选配和筛选及杂交棉的F2代利用问题,提出了全面利用F1代的杂种优势。     

Is there more in ‘gamete quality’ than quality of the gametes? A review of effects of female mate choice and genetic compatibility on offspring quality

Zygote quality is a major issue in production aquaculture, and has been considered, for example, in terms of lipid content, readiness of the female spawner, potency of the male spawner and other issues. In the mean time, evolutionary biologists have been considering issues of mate choice and genetic compatibility of the parents. This paper gives an overview of the main hypotheses of female mate choice, the reasons for multiple mating of females and their potential effects on offspring quality. I suggest how these ideas, if taken into account in commercial aquaculture, might increase the value added of several species in commercial aquaculture, which is impeded by poor offspring quality. Theoretical and empirical research shows that females in general choose partners actively among different males and that females often mate with multiple males. Both active mate choice and multiple mating improve the quality of the offspring, for example as enhanced survival and growth. Active female choice also occurs at the gamete level, and according to the ‘cryptic female choice hypothesis’, eggs are able to affect which sperm from which male will be fertilized. Several proximate mechanisms regarding how the eggs can affect the sperm have been demonstrated. Improved offspring quality of active female choice, cryptic female choice and multiple mating are all in accordance with the ‘genetic incompatibility hypothesis’. This hypothesis states that the quality of the offspring depends on the degree of intragenomic conflicts due to interactions between maternal and paternal haplotypes, for example as increased immunity against a wider range of pathogens when choosing a mate with different immune‐coding alleles than your own. According to the genetic incompatibility hypothesis, eggs from a particular female are expected to do well when fertilized by a particular male, whereas eggs from the same batch from the same female should do poorly when fertilized by other males. Such sire–dam interactions have been demonstrated empirically. I argue that if such a sire–dam interaction is a general phenomenon, this might have major implications for the commercial aquaculture industry, concerning choice of number of brooders, fertilization method, methods to preserve gametes, spawning protocols and breeding programmes.     

维生素C对半滑舌鳎亲鱼繁殖性能及后代质量的影响

本试验旨在研究维生素C对半滑舌鳎亲鱼繁殖性能及后代质量的影响.在基础饲料中分别添加0.5％(C0.5组)、1.0％(C1.0组)和1.5％(C1.5组)的L-抗坏血酸-2-磷酸酯(作为维生素C添加剂),制成维生素C添加量分别为0.175％、0.350％和0.525％的3种试验饲料.每种试验饲料饲喂3.5龄滑舌鳎雌性亲鱼15尾[(1.15±0.11) kg/尾]和雄性亲鱼20尾[(0.25±0.05) kg/尾],饲喂2个月后人工育苗.结果表明:添加维生素C对半滑舌鳎雌性亲鱼的性腺指数和相对产卵量以及雄性亲鱼的精液浓度没有显著影响(P＞0.05),添加0.350％维生素C能显著提高雄性亲鱼的性腺指数(P＜0.05).随饲料中维生素C添加量的增加,上浮卵率和孵化率显著上升(P＜0.05),初孵仔鱼畸形率显著下降(P＜0.05).C1.0和C1.5组的卵径、受精率、初孵仔鱼体长以及血清中雌二醇和睾酮含量均显著高于C0.5组(P＜0.05),而C1.0与C1.5组之间无显著差异(P＞0.05).C1.5组卵中大油球直径显著高于C05组(P＜0.05).卵子和上浮卵中维生素C含量随饲料中维生素C添加量的增加呈上升趋势,但各试验组间无显著差异(P＞0.05).此外,饲料中添加维生素C能不同程度地提高亲鱼肝脏、卵巢、精巢和卵子中维生素C含量,提升亲鱼血清、肝脏、卵巢、精巢、卵子和精液中超氧化物歧化酶活性并相应降低丙二醛含量.由此可见,本试验条件下,饲料中添加高剂量(0.525％)的维生素C更有利于促进半滑舌鳎亲鱼性激素的合成,改善亲鱼的繁殖性能,提高精卵质量,促进受精卵孵化,减少仔鱼畸形.     

基于压力-状态-响应模型的寒地粳稻杂交育种后代选择与实现

为提高育种杂交后代选择效果,引入压力-状态-响应(PSR)模型对影响寒地粳稻杂交育种后代的遗传、环境和选择因素进行探讨。构建1个目标、3个准则和18个指标组成的寒地粳稻杂交育种后代选择概念模型与评价体系,并采用客观熵权和功效评分相组合方法进行综合指数评价。结果表明:在PSR模型设计环境下,‘绥粳18’杂交育种9个世代杂交后代均表现出穗颈瘟权重值最大,其次是倒伏级别,再次是空壳率,寒地生态环境下抗穗颈瘟发病指数、抗倒伏级别和空壳率水平是水稻育种杂交后代选择最重要的考虑指标。PSR系统评价中,各子系统的影响力大小依次是响应子系统(权重为0.6867)状态子系统(权重为0.2651)压力子系统(权重为0.0482);各指标值变异系数为0～200.4%,大范围变异利于提高后代选择育种效果。与目前多依据株型理论选择杂交后代系谱相比,运用PSR模型理论与评价体系方法,创建动态压力选择环境,客观评价指标特征,并引入专家决策管理,能够有效克服单纯依靠育种经验、定性定量不结合、多注重性状选择以及响应决策不系统而导致多优性状聚合难、鉴定难、选择效率低等问题,具有较好可行性、可靠性和实用性,可以获得更加合理的寒地水稻育种杂交后代选择方案。本研究结果可为加快寒地优质高产多抗广适突破性水稻新品种选育提供有益参考和技术依据。     

波尔山羊杂交后代肌肉组织学特性研究

利用SPSS软件 ( 1 0 0版 )统计分析了杂交代数、体躯部位两因素对波尔山羊和唐山奶山羊杂交后代肌肉组织学特性的影响 ,同时分析了肌肉组织学特性与其肉用性能的相关关系。结果表明 :杂交代数对肌肉组织学特性有一定影响 ,不同杂交代数在眼肌肌纤维密度方面差异显著 (P <0 0 5 ) ;而体躯部位对肌肉组织学特性影响不显著 (P >0 0 5 )。股二头肌肌纤维面积、肌纤维直径与绝大多数肉用性能均达到了显著水平 (P <0 0 5 ) ,其中与肉骨比、屠宰率和腰腹肌肉重达到了极显著水平 (P <0 0 1 ) ,眼肌肌肉组织学特性只有部分与肉用性能达到了显著水平 (P <0 0 5 ) ,而臂三头肌肌肉组织学特性与各肉用性能指标间的相关性均未达到显著水平 (P >0 0 5 )。     

‘砀山酥梨’与‘苹果梨’杂交后代果实性状遗传趋势的研究

以‘酥梨’与‘苹果梨’杂交后代群体为试材,测量果心大小、单果重、可溶性固形物等7个指标,分析其分布规律,以期为梨遗传育种提供参考依据。结果表明：杂交后代单果重普遍较小,在100~120g区间分布最多,总体呈正态分布趋势。果形指数在0.98~1.04和1.07~1.19为集中分布区,果形与母本‘酥梨’相近。杂交后代果形指数、单果重、可溶性固形物含量、果心大小总体呈正态分布趋势,属数量遗传性状。果皮颜色以传统梨的黄色为主,占总数的59.42%,倾向于母本的果实颜色。后代果柄出现肉质化,果实的脱萼率为38.65%。     

方正银鲫雌核发育后代肌肉营养成分与异源父本的比较

通过对异育银鲫(Ⅰ)Carassiusauratusgibelio♀×CyprinuscarpioL ♂、异育银鲫(Ⅱ)Caras siusauratusgibelio♀×Carassiusauratuscuvieri♂、生产所用的亲本鱼方正银鲫Carassiusauratusgibelio(Bloch)、鲤CyprinuscarpioL 和白鲫CarassiusauratuscuvieriTemmincketSchlegel共5种鱼的肌肉营养成分进行分析,结果表明:母本方正银鲫的肌肉蛋白质含量(180 3mg/g)和肌肉干物质中的氨基酸总量(714 277mg/g)、人体必需氨基酸含量(280 164mg/g)和呈味氨基酸含量(281 091mg/g)等指标均高于其后代和父本鲤、白鲫;雌核发育后代的肌肉营养成分介于双亲之间,低于母本方正银鲫而高于父本鲤和白鲫;以白鲫为父本的异育银鲫(Ⅱ)的肌肉营养成分要高于以鲤为父本的异育银鲫(Ⅰ);异育银鲫可利用雌核发育的生长生物学效应,但对肉质的改良没有作用。     

母猪哺乳期蛋白限饲对后代肉质性状及肌纤维发育的影响

试验采用二因素试验设计,选取12头胎次、体况相近的母猪(民猪、长白猪各6头)进行纯种繁育,旨在探讨哺乳期母猪蛋白限饲对子代肉质及肌纤维发育的影响,每个品种母猪随机分为两组,在哺乳期饲喂不同蛋白水平日粮(对照组日粮蛋白水平为18％,限饲组日粮蛋白水平为9％),哺乳期为28 d,子代断奶后饲喂相同的标准日粮。测定子代猪18...