陕西省玉米杂交种种质基础分析

对1984年～1993年陕西省种植面积在0.67万hm~2以上的玉米杂交种种质基础进行了分析,结果表明:陕西省玉米杂交种的生产已基本达到单交种化;生产上使用的杂交种比较集中,省外系和国外系组成的杂交种面积较大;玉米杂交种亲本系利用更趋集中,种质基础狭窄;玉米自交系主要采用以窄基为主的选育方式;种质杂交模式主要是美国的瑞德黄马牙、兰卡斯特分别和中国的唐山四平头、旅大红骨的杂交形式。     

水稻高世代回交导入系耐盐性的遗传研究

水稻是一种对盐敏感的作物，盐分是限制水稻产量的主要因子之一。本研究利用广泛推广种植的杂交籼稻的亲本珍汕97（ZS97）和测序粳稻品种日本晴（Nipponbare）杂交、回交构建的导入系，对水稻的耐盐性进行遗传研究。用88份导入系作苗期盐胁迫（0．3％氯化钠）处理试验，发现6份导入系的耐盐性同受体亲本ZS97有显著差异，其中5份导入系耐盐，1份对盐敏感。图示基因型分析表明5份导入系中含有少数外源导入片段及耐盐相关的基因。     

花生抗锈病种质筛选及抗性QTL分析

锈病是影响花生产量和品质的主要真菌性病害。本研究以“中花10号×ICG 12625”构建的重组自交系群体(RIL)为材料,在武昌和阳逻两个环境中对其F₈群体进行锈病抗性鉴定,获得了8份抗锈病材料(QT0348、QT0368、QT0400、QT0402、QT0419、QT0458、QT0463和QT0485)。利用前期构建的遗传图谱进行QTL分析,检测到10个与锈病抗性相关的QTL,贡献率为4.54%～10.78%,分布于7条染色体上。其中,qBB06.1和qBB06.4为重复一致的QTL,贡献率为10.76%。根据侧翼标记在物理图谱进行比对,发现对应区段含有193个基因,其中178个基因被注释,功能注释基因中有1个NBS-R基因。本研究结果为花生抗锈病的遗传改良奠定了基础。     

甘蓝型油菜DH系在不同生态区SPAD值的差异分析

以甘蓝型油菜纯合双单倍体(DH)为材料,研究不同生态环境下油菜叶绿素SPAD值的变化状况,揭示叶绿素含量遗传表现规律,创制更高叶绿素含量种质资源,以期为油菜高光效育种奠定方法和理论基础。选取了170份甘蓝型油菜DH系,连续3年分别种植在冬油菜区(陕西大荔)和春油菜区(甘肃张掖)。结果表明:无论是不同遗传背景的DH系、还是同一亲本下的不同DH系材料,油菜DH系叶绿素含量在田间既表现出遗传稳定性,又容易受到外界环境影响,即在相似的生态条件下,同一区域即便不同年份的各DH系材料,叶绿素SPAD值的表现基本一致,但在不同生态区,油菜DH系的SPAD值差异很大。通过对油菜DH系亲本和DH系叶绿素SPAD值频数分布分析,叶绿素含量连续3年在2个生态环境具有广泛的连续分布,并且服从正态或者近似于正态分布,以及超亲分离的特点。这些都表明油菜叶绿素含量是一个典型的数量性状,受到多对基因的控制。     

黑米稻三系配套选育初报

采用人工制保、制恢的方法 ,育成了黑米稻不育系 2个 (“大黑A”和“血黑A”)和恢复系 3个 (“黑恢 1号”、“黑恢 2号”和“黑恢 3号”) ,于 1 997年成功地实现了黑米稻三系配套[1] ,与此同时进行了黑米稻不育系、恢复系与白米稻不育系、恢复系的配组试验。试验结果表明 :黑米杂交稻优势强、经济性状互补明显 ,较好地克服了传统黑米稻品种产量低、抗性和株叶形态差的缺点 ,而且黑米稻不育系、恢复系与相应的白米稻恢复系、不育系配组 ,其F1代大多数仍为黑米     

Detection of additive and additive×environment interaction effects of QTLs for yield‐component traits of rice using single‐segment substitution lines (SSSLs)

Additive effects (A) and additive‐by‐environment interactions (A×E) for five rice yield components were analysed using 20 SSSLs under mixed linear model methodology. Thirty‐one QTLs were detected. Different yield components have different QTL‐by‐environment (Q×E) interaction patterns. No A×E interaction effects were detected for the four QTLs for panicle number (PN). Four QTLs detected for spikelets per panicle (SPP) had A×E interactions. Five of seven QTLs detected for grains per panicle (GPP), two of 10 QTLs detected for 1000‐grains weight (GWT) and three of six QTLs detected for seed set ratio (SSR) showed significant A×E interaction. Most of these QTLs were distributed in clusters across the genome. The complexity of linkage and pleiotropy of these QTLs plus environmental effect may result in the diversity of the yield phenotype in the SSSLs. Only S19 exhibited a significant increase in yield with a predicted gain by 281.58 kg ha^?1. The results may be useful to design a better breeding strategy that takes advantage of QTL‐by‐environment interaction effects in each of the SSSLs.     

优良玉米自交系鲁原92的选育与应用

鲁原92是利用辐照技术与常规技术相结合选育出的优良玉米自交系,该自交系具有配合力高、抗病、抗旱性好等特点。目前直接或间接利用鲁原92共选育出19个品种,累计推广面积达520万hm2。     

北方早熟春玉米种质创新及利用研究

玉米种质资源匮乏、遗传基础狭窄是制约玉米育种研究和生产水平提高的主要限制因素,开展玉米种质创新和利用研究是玉米育种研究的首要任务。简要阐述了北方早熟春玉米种质创新和利用研究的途径、方法及玉米窄基因群体的改良、引入玉米综合群体的改良、热带亚热带种质与温带种质互导、抗病玉米自交系选育等种质创新研究进展。     

Effect of genetic variation on phenolic acid and policosanol contents of Pegaso wheat lines

Total phenolic acid and policosanol contents and compositions of bran from an Italian bread wheat variety Pegaso and its 11 near-isogenic lines were measured. The near-isogenic wheat lines differed at one or more loci coding for storage proteins. The genetic variation included deletions, additions and/or combinations of variations. Almost 95% or more of phenolic acids were in the bound form. Ferulic acid was the predominant bound phenolic acid present in wheat bran samples. Other phenolic acids were p-coumaric, vanillic and syringic acids. Tetracosanol, docosanol, hexacosanol, octacosanol, tricosanol and heneicosanol were found as major policosanol compounds in their decreasing order. Highly significant genotypic differences were observed in total phenolic acid and policosanol concentrations. None of the genetic lines had higher phenolic acid contents than the parent line Pegaso, whereas some of the lines had more policosanol levels. In general, both total phenolic acid composition and contents were higher with genetic lines that varied at Glu-1 loci with 2+Dy high molecular weight glutenin subunit (HMW-GS) (Pegaso 184), variation at Gli-D2 loci (Pegaso 219) and single null A1 (variation at Gli-1/Glu-3 loci; Pegaso 30). Highest total policosanol content was observed with the double null at Glu-A1/Glu-D1 loci (Pegaso 236). These findings may lead to new opportunities for wheat breeders and eventually commercial wheat growers to promote the production of wheat with enhanced levels of health beneficial compounds.     

东乡野生稻渗入系苗期抗旱遗传及生理机制初步分析

以强抗旱性的巴西旱稻、东乡野生稻和弱抗旱性的栽培稻协青早B为对照品种,以基于萎蔫率的抗旱等级为鉴定指标,采用苗期反复自然干旱鉴定法和20%PEG6000模拟干旱法,对江西东乡普通野生稻(Oryza rufi-pogon)/协青早B//协青早B构建的回交重组自交系(Backcross inbred lines,BIL)群体(BC1F9)进行苗期抗旱机理及遗传分析。结果表明:230个BC1F9 BIL群体经2次反复自然干旱后,在1/2MS营养液恢复生长的平均抗旱等级分别为3.76和4.39,萎蔫率呈连续正态分布,暗示东乡野生稻苗期抗旱性表现为质量-数量性状遗传性状特征。将干旱处理一次后等级为1级的14个株系,在20%PEG6000模拟干旱条件下进行处理,结果与反复干旱二次后结果一致,株系1112、1168、1172和1315为强抗旱基因渗入系,可进一步用于抗旱基因的挖掘与利用。在20%PEG6000模拟干旱条件下,强抗旱性株系1112苗期叶片的可溶性糖、脯氨酸含量和SOD活性增加幅度都大于弱抗旱性株系1323,GSH含量下降幅度则低于弱抗旱株系,说明强抗旱株系渗透物质比弱抗旱株系积累快且幅度大,而细胞膜过氧化产物...