Application of Molecular Markers in Studying on Crop Heterosis

概述了分子标记的种类,分析了杂种优势研究中常用的几种分子标记的原理、特点。综述了分子标记在作物杂种优势群划分和杂种优势利用模式构建、杂种优势预测以及杂种优势遗传基础研究中的利用现状。并对分子标记在杂种优势研究中的进一步利用进行了展望。     

甜瓜杂种优势与亲本遗传距离相关性分析

以9个来源于不同地区的甜瓜品种为母本,早熟优质甜瓜品种甜帅,日本小青玉为父本,配置18个杂交组合,对组合的形态及生理生化指标进行评价.结果表明:除了果肉厚度和硬度外,单瓜重、可溶性固形物、糖酸比以及Vc含量等各性状在0.05或0.01水平上差异显著;对F1的6项指标的离亲优势的分析发现在所有指标的杂种优势计算中,不是遗传距离远的亲本就能得到的较高数值的杂交一代;精品白糖罐与甜帅的杂交后代是具有多性状高优势的优良组合.     

棉花杂种优势的研究现状及发展趋势

概述了国内外棉花杂种优势利用现状，分析了棉花杂种优势的利用途径与技术，并对今后棉花杂种优势利用的发展方向进行了探讨。认为未来最具潜力的4大应用研究领域是不育系利用、化学杀雄剂技术、杂种优势预测技术和海陆杂种棉选育。     

Crossbreeding effects for post-weaning growth traits in a project of Spanish V-line with Baladi Red Rabbits in Egypt

A four-year crossing scheme involving Spanish V line (V) and Egyptian Baladi Red (B) rabbits was carried out to produce five genetic groups: V, B, 1/2B1/2V(F₁), (1/2B1/2V)²(F₂), and ((1/2B1/2V)²)². The last genetic group was considered a new line, named APRI. Body weights (BW) and daily gains in weight (DG) from four to twelve weeks were evaluated for 13,383 rabbits produced by 330 sires and 1074 dams. An animal model was used to estimate heritabilities and common litter effects and a generalized least squares procedure was used to estimate direct additive effects, and direct and maternal heterosis.Heritabilities for growth traits were mostly moderate, ranging from 0.075 to 0.240 for BW and from 0.020 to 0.104 for DG. The V line was heavier and had better gains at each weighing than B rabbits. The F₂ and APRI were also lower in most post-weaning growth performance measures than V line rabbits. APRI rabbits were significantly lighter by 39, 26, 46, 64, and 50 g at ages of 4, 6, 8, 10, and 12 weeks, respectively, relative to the purebred V line, while APRI was significantly heavier by 36 and 127 g relative to the B line at 4 and 12 weeks. The V line, in general, had a higher DG than B line. The differences were 3.15, 7.91 and 1.95 g/d at age intervals of 8–10, 10–12 and 4–12 weeks. Differences in direct additive effects between the two lines were in favor of V line rabbits reaching 15.0% (76 g) at 4 weeks and 13.3% (195 g) at 12 weeks. Direct additive effects for DG were significant during most age intervals reaching 35.7% (7.19 g/d) in the interval of 10–12 weeks. All estimates of direct heterosis were positive and ranged from 4.9 to 16.7% for BW and 14.4 to 29.5% for DG, but the estimates for maternal heterosis were, in most cases, significantly negative and ranging from − 4.5 to − 15.2% for BW and from 20.6 to − 36.9% for DG. If the results are confirmed at commercial farms, the APRI line could be reared in heat stress conditions.     

中国超级杂交稻育种研究的进展与策略探讨

介绍了中国超级杂交稻育种的目标,技术路线和育种理论,综述了中国超级杂交稻育种研究的概况,以及在亲本选育,品种选育和分子育种技术等方面取得的进展,阐述了通过加强水稻种质资源的创新与利用,扩大亲本遗传差异,提高水稻生物学产量,改善水稻生理机能等技术策略,选育出综合性状优良的超级杂交稻新组合,进一步提高中国超级杂交稻产量水平。     

过氧化物酶杂合性与玉米F1产量性状相关性分析

探讨过氧化物酶的同工酶在产量杂种优势预测中的作用,在利用玉米F1代杂种优势群的基础上,选用安徽科技学院玉米研究所选育的6个高产组合,分析了玉米F1代杂交种过氧化物酶的同工酶杂合性与产量性状的相关性。产量杂种优势与亲本数目具有一定的相关性,同时,产量性状与过氧化物酶的同工酶杂合性具有一定的关系,但并非杂合性越高产量杂种优势越强;利用过氧化物酶的同工酶杂合性可以作为预测产量杂种优势表现的一个参考指标。     

河南省优质油菜杂种优势利用研究进展

“九五”以来,河南省油菜科研工作者,根据国际油菜科技发展的两大趋势(优质化与杂种化),将品质育种和杂种优势利用相结合,采用细胞质雄性不育技术,开展优质油菜“三系”杂种优势利用研究,使优质和高产得到较好的统一。育成双低、高产油菜杂交种豫油4号、豫油5号、杂9522、杂97060、杂98033、丰油9号、杂双1号、杂双2号、华油2000等,对河南乃至全国杂交油菜的发展起到了重要的推动作用。同时,加强油菜小孢子培养、种间杂交、分子标记等生物技术基础应用研究,创造出一批优异种质和“三系”材料,为今后选育出更加优良的杂交品种奠定了物质基础。目前,一批优质杂交新组合正在参加国家和河南省油菜区域试验和生产试验。     

甘蓝型油菜品质性状相关分析及F2品质预测

对5个甘蓝型油菜细胞质雄性不育系与33个不同来源的恢复系材料以NCII法配制的165个杂交组合F2代的品质性状、配合力、杂种优势进行了分析。结果表明:F2代各品质性状、配合力、杂种优势之间都具有显著或极显著的正相关关系。杂优利用是油菜品质改良的有效方式,父母本品质及配合力决定了杂优利用效果,而父母本品质配合力之和可以用来预测F2代的品质和进行亲本的选配。     

两个杂交棉F1、F2代及亲本冠层结构与物质生产特征

以杂交棉石杂2号和新陆早43的F₁、F₂代及亲本NT2、H2、4-14为试材,通过测定不同生育时期各材料叶面积指数(LAI)、叶倾角(MTA)、冠层光截获率等指标,分析了各指标变化对群体光合物质生产的影响。结果表明,2个杂交棉F₁代LAI具有超亲优势,冠层光截获率具有中亲优势; LAI和冠层光截获率具有明显的母系遗传特性,而MTA受到父本的显著影响。F₂代冠层结构主要受F₁代相关指标和衰退率的影响,LAI中亲优势减小了衰退率; 杂交棉F₁代光合物质积累主要受亲本参数和超亲优势的影响,F₂代主要受F₁代参数的影响。杂交棉光合物质积累最大增长速率和直线增长期开始时间较晚,直线增长期及活跃增长期较长,最终积累量和最大增长速率较高。杂交棉F₁代具有明显的光合生产和产量优势,F₂代具有一定的产量优势。以选择具有优化冠层结构的亲本为基础,组配具有较大MTA的父本和较大LAI的母本,有利于改善杂交棉光合性能,提高群体光能利用率,进一步挖掘产量潜力,为杂交棉高光效组合的选育及提高F₂代应用提供理论依据。     

Physio-morphological Studies of F1 Hybrids in Rice (Oryza sativa L.): Photosynthetic ability and yield

Summary

Photosynthetic ability in terms of CO₂ exchange rate and leaf area, dry matter accumulation (dry weight) and other important growth components along with yield and yield contributing characters in two F₁ hybrids of Akebono × Chiyonishiki (A × C) and Zenith × Akebono (Z × A) were studied. The photosynthetic rate at the flowering stage was lower than that at the panicle initiation stage in all the inbred parent cultivars and F₁ hybrids. Heterosis in photosynthetic rate was higher at the panicle initiation stage than that at the flowering stage. Pre-anthesis leaf area in the F₁ hybrid was significantly larger than that in the parent cultivars. However, the post- anthesis decline in leaf area was more rapid in the F₁ hybrids than in the parent cultivars and its magnitude was the highest in the F₁ hybrid of Z × A which was tall having long and curved panicles. Pre-anthesis dry matter accumulation in both hybrids was significantly higher in the F₁ plants than the parental cultivars, but post-anthesis dry matter accumulation in the F₁ hybrid was lower than the mid-parental value in Z × A. The degree of heterosis in grain yield varied with the hybrid combination, an average heterosis being 1.03. Heterosis in grain yield was closely associated with heterosis in harvest index.