矮败小麦的遗传研究

矮败小麦是具有矮秆基因标记的显性核不育材料,显性雄性不育基因Ms2与显性矮秆基因Rht10连锁十分紧密,其连锁交换值仅为0.18,而紧密连锁基因Ms2和Rht10与着丝点间的遗传距离为31.17个交换单位。     

轮回选择对矮败小麦生理及产量性状的影响

对矮败小麦回交、杂交后代可育株、杂交父本或回交亲本的叶绿素含量的相对比值(SPAD值)以及叶面积系数的测定,抗病性、农艺性状的观察结果表明:部分矮败后代可育株叶绿素含量的相对比值高于回交或杂交亲本,部分矮败小麦回交2代与新品系杂交后代可育株叶面积系数高于父本;部分矮败小麦回交、杂交后代可育株白粉病、锈病抗性高于回交亲本;部分矮败材料回交、杂交后代穗部产量性状有超亲优势.     

矮败小麦研究进展及其在安徽的应用

介绍了矮败小麦的创制过程和四大优点,以及矮败小麦在远缘杂交、杂交育种、轮回选择等方面的研究进展,同时介绍了安徽省矮败小麦与等离子诱变相结合的育种技术体系和成果,并对矮败小麦的未来发展趋势进行了展望。     

不同遗传背景矮败小麦的性状表现

以9种遗传背景的矮败小麦近等基因系为材料，研究了矮秆不育株的株高、抽穗期、开花期、每株穗数、穗长、每穗小穗数和异交结实率。结果表明，不仅矮秆不育株与高秆可育株的株高存在显著差异，而且不同遗传背景的矮秆不育株的株高也程度不同的存在差异；矮秆不育株比高秆可育株的抽穗期平均晚2天，而开花期平均晚1天左右；在     

不同遗传背景矮败麦发育上的几个特点

１９９４－１９９５年通过对转育４代的１２０个不同遗传背影的矮败麦后代分离出的不育株与散粉株的比较得到如下结果：１．不同遗传背影的不育株与其姊妹散粉体的株高均差异明显，且此差值的大小与散粉株的株高呈极显著正相关，不同遗传背影下散粉株株高的变异九最小，不育株次之，而以散粉株与其姊妹不育株高差值的变异系数最大；２．不育株的抽穗期比其姊妹散粉平均推迟３．４ｄ，d开颖传粉期推迟更多。     

小麦群体改良过程中蓝矮败的选择技术与技巧

轮回选择是小麦群体改良的有效方法,过去利用蓝标不育(隐性基因控制)及保持体系、太谷核不育系、"矮败"不育系为工具载体进行轮回群体改良多有不便。而蓝矮败是蓝粒、矮秆、花药败育,3个显性单基因连锁遗传的单体附加系,其种子下地前可以辨别育性,是用于轮回选择的一种便捷高效的理想工具载体。利用蓝矮败拓建了几十个不同类型的轮选群体与综合基因库,通过对8年来群体改良经验教训的总结,形成了蓝矮败选择的技术与技巧:田间选择与室内考种选择相结合,依据不同轮选群的特点,创造性状表现的适宜环境,明确群体选择重点,掌握有利时机,根据性状的遗传特点制定选择策略,确定不同性状的宽严尺度,采取适宜的选择强度,利用生态条件强化自然选择,重视饱满度选择,以聚集更多有益性状基因,提高群体改良效果。掌握这些选择方法与技巧可以取得事半功倍的效果。     

利用矮败小麦建成高效育种技术新体系

“矮败小麦创制与高效育种技术新体系建立”研究,通过了由庄巧生、李振声、刘大钧、董玉琛4位院士和来自全国各主要麦区专家组成的鉴定委员会的成果鉴定。专家们一致认为,刘秉华等研究人员经过10多年反复探索与实践,利用矮败小麦建立的高效育种技术体系创新性强、实用效果好、发展潜力大,整体达到国际领先水平。矮败小麦育种技术体系包括理想的轮回选择工具、方便实用的轮回选择技术和丰富多彩的改良群体3部分内容。1　理想的轮回选择工具 (矮败小麦 )矮败小麦是具有矮秆基因标记的太谷核不育小麦。在矮败小麦中,矮秆基因Rht10与雄性不育基因Ms2在4D染色体短臂上连锁十分紧密,交换率仅有0.18     

矮败小麦及应用途径分析

矮败小麦是具有矮秆基因标记的显性核不育材料，非矮秆品种与之授粉，后代群体中的矮秆株是雄性不育的，而非矮秆株是雄性可育的。矮败小麦是太谷核不育小麦的第二代产品，多方面优于太谷核不育小麦，在常规育种、轮回选择和基础研究中有远大的应用前景。     

第一届矮败小麦育种技术研讨会在北京召开

矮败小麦是中国农业科学院作物科学研究科所创制的具有矮秆基因标记的太谷核不育小麦,是具有自主知识产权的遗传资源。矮败小麦授以非矮秆父本的花粉,其后代总是有一半靠异交结实的矮秆不育株,一半靠自交结实的非矮秆可育株。矮败小麦可以作为育种工具用于单交、复交、回交、阶梯杂交和远缘杂交等多种育种途径,特别是便利地应用于轮回选择育种。2006年12月11日-12日,在北京召开了“全国矮败小麦育种技术研讨会”,会议由中国农业科学院主持,来自全国科研院所科技人员200人参加了会议,科技部、农业部和中国农业科学院有关领导参加了会议。28位…     

秋水仙素和二甲基亚砜诱导矮败小麦孤雌生殖的效应

在隔离区内，以矮败小麦轮回选择群体中的不育株为供试亲本，用秋水仙素（Ｃｏｌ）和二甲基亚砜（ＤＭＳＯ）诱导孤雌生殖。结果表明，Ｃｏｌ和ＤＭＳＯ均具有诱导不育株孤雌生殖的作用，并且二者之间存在极显著的互作效应。同一药剂不同的诱导方法，其诱导效果有差异；小穗剪颖处理的孤雌生殖结实率较高；处理时间和套袋与否对孤雌生殖结实率影响不显著。孤雌生殖纯系在纯度和遗传稳定性方面均接近于对照品种（丰抗８号）。从遗传理论和育种实践的角度，讨论了药物诱导矮败小麦孤雌生殖的可行性及在小麦育种中的应用价值     

优质蛋白质玉米的研究现状和利用价值

随着人们生活水平的提高、对仪器多样化的要求和畜牧业的快速发展，优质蛋白质玉米以其营养价值高、饲用价值高、用途广泛和种植效益好而越来越受到人们的广泛重视。调整玉米种植结构，大力推广和发展优质蛋白质玉米必将推动玉米产业的快速发展，对发展畜牧业、推动食品工业和改善人民的营养状况具有十分重要的意义。     

论品种特性及安全用种

自<种子法>实施以来,种子经营实体越来越多,他们纷纷从全国许多育种单位引种、代销,形成了多家引种、试验、示范、经营推广的局面.同时,由于基层农技力量削弱,造成了局部地区品种布局失去了科学支撑,品种的乱引、乱调、乱种现象日趋严重,给农业安全生产带来极大威胁、.因此,结合品种特性,搞好品种布局,给农民提供科学的技术依据和指导,是各级种子经销商首先应做好的事情.     

Genetic analysis of the nitrogen and phosphorus utilization efficiencies in mature spring barley plants

Inheritance of the efficiency of nitrogen and phosphorus utilization in grain production was studied in diallel hybrids of spring barley. Effects of varied NPK fertilization and soil moisture on the genetic variance was evaluated at maturity in pot‐ and field‐grown plants. A preponderance of general combining ability effects was found for the efficiency ratios and utilization efficiencies, suggesting that the generative efficiency indices were mainly controlled by an additive genetic system. However, the relatively high narrow‐sense heritabilities (0.33‐0.81) found under optimal conditions tended to decline to 0.00‐0.36 following water and nutrient shortages. The importance of non‐additive gene effects for utilization efficiencies was demonstrated in the field under reduced nutrition. This leads to the conclusion that the involvement of additive gene action should facilitate selection efforts only under favourable environments. Selection delayed until later hybrid generations should be used when trying to improve the nutrient efficiency of barley under less favourable nutrition conditions.     

Genetic characteristics of self fertility in highbush and half-high blueberries

Summary Parents and ten progeny from each of ten controlled crosses, and thirteen progeny from G65 x Ashworth were self and outcross pollinated to study the inheritance of self fertility and the associations between self fertility and zygotic inbreeding levels in highbush and half-high blueberry genotypes. Reductions in self fertility were apparently a response to increased inbreeding. Both percent fruit set and seeds per pollination were negatively associated with family zygotic inbreeding coefficients. Although inbreeding depression was responsible for much of the observed self fertility responses, an environmental component was apparent as well. A continuous distribution of self fertility levels among the G65 x Ashworth progeny provided little evidence for simple inheritance of this trait. Estimates of heritability were not significant and some evidence of specific combining ability was detected, indicating that parental self fertility was not predictive of the self fertility of the progeny in this study. Variation for self fertility including high levels in some individuals indicates a potential level of self fertility which could be incorporated into future selections and cultivars.     

Genetic effects and heterosis of flowering and fruit characteristics of tropical pumpkin

Tropical pumpkin is an important vegetable in many lowland tropics. Estimation of genetic effects for a fixed set of genotypes may yield information on the presence of different types of gene action for important traits. Six landraces and one diallel set of their progeny were evaluated for time from planting to female anthesis and fruit characteristics. Variety effects and heterosis mean squares were significant for the days to female anthesis, the weight of the first mature fruit, the mean fruit weight and soluble solids, indicating the presence of both additive and non‐additive gene actions. Only variety effects were significant for the days to the first mature fruit. These characters could be improved by recurrent selection. Selection for heterosis would be effective except for the days to the first fruit to mature.     

Genetic characteristics of water-use related traits in sugar beet

Improved water use efficiency (WUE, the ratio of dry matter produced to water used) can potentially result in yield improvement in water-limited environments. Genetic variation in WUE can be exploited by carbon isotope discrimination (Δ) in C₃ species. In order to improve WUE and its associated traits, it is necessary to understand the genetic systems controlling the expression of these traits. A full diallel analysis carried out on five inbred lines selected from a previous field experiment revealed that Δ, WUE and specific leaf weight (SLW, the ratio of leaf dry weight to leaf area) had high narrow-sense heritability (H_n, the ratio of additive variance to phenotypic variance) and were controlled largely by additive gene effects indicating that these traits can be improved by selection in early generations. In contrast, maternal effects had a large influence on phenotypic expressions of total dry matter yield, total water use, chlorophyll content and leaf area suggesting the important role of selection of female parent for improvement of these traits. The parental line R49 was found to be the best general combiner for all of the traits. Genetic variation in SLW was strongly associated with Δ (R ² =0.49, P < 0.01). This implies that SLW could be used as an inexpensive alternative measure for Δ to assess genotypes during the early phases of breeding programmes.     

Genetic variation in nitrogen uptake and utilization efficiency in a segregating DH population of winter oilseed rape

Genetic variation in nitrogen (N) use efficiency, N uptake, and N utilization was analyzed in a doubled haploid (DH) population derived from winter oilseed rape cultivars. The aim was to analyze the relative importance of uptake and utilization efficiency and to identify parameters that allow an easy selection of N efficient genotypes. Fifty-four DH lines were tested in four to seven environments at two levels of N supply: no fertilization and 240 kg N ha^?1. N uptake efficiency is defined as the amount of N acquired by a genotype as the proportion of the N available in the soil. N utilization efficiency is measured as unit grain yield per unit of N taken up. Significant genotypic variation was observed for both uptake and utilization efficiency. At low N supply, variation in N efficiency was mainly the result of differences in uptake efficiency. Seed yield was correlated positively with N uptake and N utilization efficiencies at low N supply and with N uptake at high N supply. The correlation was positive between harvest index (HI) and N use efficiency at both N levels (r = 0.45**; r = 0.36**) and for HI and N utilization at low N supply (r = 0.46**), indicating that a shorter plant ideotype might be more N efficient. The interaction between genotypes and N supply for grain yield was highly significant, and the correlation between low N and high N was of only medium size (r = 0.60**), suggesting the possibility of selecting genotypes with specific adaptation to low N supply.     

黑龙江省水稻主要品质性状与食味评分的相关性分析

对黑龙江省近年育成的63个水稻品种主要品质性状与食味评分的相关性进行了分析。结果表明:出糙率、整精米率、垩白粒米率、垩白度和直链淀粉含量与食味评分呈显著或极显著负相关;而胶稠度与食味评分呈显著正相关,即随着胶稠度提高,食味评分呈上升的趋势。通过明确主要品质性状对食味评分的影响,为今后黑龙江省优质水稻品种选育提供参考。     

刈割时间对青贮玉米秸秆饲料营养成分的影响

国外较多的研究是从整株玉米青贮的角度研究不同品种和收获成熟期对青贮饲料营养价值的影响，而国内对青玉米秸秆青贮的研究报道多涉及提高青贮饲料的品质，为此试验选用收刈时间（生长期）为92、94、96、98、100、102和104d的高油115玉米青秸秆调制青贮饲料，研究玉米秸秆收刈时间对青贮饲料营养成分的影响，结果表明收刈时间明显影响青贮饲料的氨态氮、CP和NDF含量，尤其是明显影响青贮饲料的有机物体外降解率，收刈时间对青玉米秸秆青贮饲料的乳酸、丁酸含量和ADF含量没有明显的影响(p>0.05)。     

Genetic diversity in camelina germplasm as revealed by seed quality characteristics and RAPD polymorphism

Camelina is an alternative oilseed crop species with limited information about the origin and diversity of available germplasm. Therefore, a set of 130 camelina accessions from a world collection was evaluated for oil content, protein content and 1000‐seed weight in field experiments grown in three macro‐environments in Austria. Based on phenotypic data, accessions were categorized into four groups with different seed characteristics using k‐means cluster analysis or principal component extraction. Subsequently, a representative set of 41 accessions was subjected to random amplified polymorphic DNA (RAPD) analysis. Of 24 primers, 15 were polymorphic producing a total of 30 marker loci. Genetic distance estimates between the 41 accessions were calculated, based both on RAPD polymorphism and on seed quality characteristics, and dendrograms were generated for comparison. Similarities were found between the two different clustering approaches, and grouping was partly in agreement with pedigree information or geographic origin. However, as the two estimates of diversity sampled different segments of the genome, i.e. regions coding for seed characteristics or phenotypically neutral genomic regions highlighted by discrete markers, the correlation between the two distance matrices was low.