高品质抗虫棉选育初报

我国抗虫棉的选育取得了可喜进展,但抗虫棉品种的纤维品质需要改良.因此,培育纤维长、强、细兼备的高品质抗虫棉是"十五"棉花育种的重点内容.石家庄市农科院在"九五"国家科技攻关的同时,就开始注重抗虫棉品种纤维品质改良研究,本文就我院高品质抗虫棉的选育结果略作分析,为我国抗虫棉品种纤维品质改良提供依据.     

我国棉花育种成就与种植结构调整战略

我国棉花育种的主要成就突出表现在:转基因抗虫品种大规模应用,杂交棉面积逐年扩大,抗黄萎病和纤维品质改良进展迅速,不同棉区纤维品质改良目标明确,种子产业化速度加快.随着棉花种植结构战略调整,我国需要发展两熟制种植模式,两熟种植区域适当北移,增粮保棉,一熟棉区向滨海滩涂和旱碱地区适当转移.为此,需要选育生育期较短和耐旱碱的棉花新品种,改进棉花株型,研制和开发主要品种的配套栽培技术,提高水肥利用率.     

1973-2000年黄河流域棉花品种改良与应用状况分析

利用1973-2000年国家黄河流域棉花区域试验资料及同期该棉区棉花品种推广的统计数据,总结了棉花品种改良的主要成绩,分析了棉花品种不同性状的育种效率.结果表明产量性状的遗传改良效率逐年下降,早熟性、抗逆性和部分纤维品质指标的改良效率有所提高.探索性提出了提高育种效率的途径和方法.分析了棉花良种普及率及自育品种变化情况,针对目前美国转基因棉花在该区生产中优势,加强国产品种的推广已成当务之急.     

建国以来我国黄淮棉区棉花品种的遗传改良Ⅱ. 纤维品质性状的改良

本文以不同历史时期的10个代表性棉花品种的2年5点试验和1973～1996年棉花品种区域试验的历史资料研究我国黄淮棉区自50年代以来棉花品种纤维品质性状的遗传改良效果。 结果表明, 建国40多年来, 该棉区棉花纤维品质育种取得了较大进展。 在品种的增产潜力以每年8 kg/hm2增长的同时, 纤维强度约提高了2.35 CN/dtex, 产量与     

棉花优异品质及抗性基因挖掘与分子育种

棉花品质、产量、抗性等均是多基因控制的数量性状,其表现型受基因型和环境的共同影响,且纤维品质和产量性状之间存在较大的负相关,采用常规育种手段实现棉花纤维品质与产量的同步改良具难度很大,针对棉花品质、产量、抗性等性状形成的遗传基础这一关键科学问题,棉花品种分子设计研究团队以陆陆种内分离群体、陆海种间分离群体等材料,交叉利用分子数量遗传学、功能基因组学和分子育种学等研究手段,在陆地棉优质品质及抗性基因挖掘、海岛棉优质品质及抗性基因挖掘以及分子标记辅助方法开发及棉花新品种培育等方面取得了一系列研究成果。为棉花品质、产量、抗性性状形成的同步改良奠定了重要基础。     

2019年中早熟棉花品种（系）比较试验

对兵团第二师种植的棉花品种(系)进行比较试验,鉴定其丰产性、纤维品质、综合表现及与对照品种的差异,客观评价参试棉花品种(系)特性与生产利用价值,为推广提供科学依据。试验结果表明,在参试的9个棉花品种(系)中,新陆中38号棉花品种产量和纤维品质表现均较突出,新陆中54号和新陆中74号品种霜前皮棉产量较高。     

棉花纤维品质分子育种的现状及展望

棉纤维是重要的纺织工业原料。随着人民群众对衣着要求的普遍提高,纺工部门引入高效快速的纺纱技术,对棉花品种的总体纤维品质,提出了更高的要求。目前国内外棉花育种家除了利用常规技术外,还大规模开展了棉纤维品质改良的分子育种研究。本文综述了国内外利用克隆出的棉纤维发育基因以及外源基因开展棉纤维品质改良的转基因育种和棉纤维优质基因的分子标记筛选和辅助选择育种的研究进展。同时,根据我国目前棉花品种品质水平、生产状况,提出了棉花品质育种策略。     

湖北省棉花纤维品质现状分析及品质区划初步探讨

对湖北省“九五”以来育成的16个棉花品种的纤维品质进行分析,结果表明：湖北省棉花纤维长度较好,比强度偏低,马克隆值偏高。湖北省生产的原棉品质居全国中上等水平,纤维色特征相比较差。在分析湖北省三大棉区的纤维品质特征基础上,提出将鄂东、鄂北、江汉平原棉区分别建成中长绒、中短绒和中绒三种类型原棉生产基地。对如何提高湖北省原棉质量,从改良棉花遗传品质、提高生产品质、实施品质区划等方面进行了讨论。     

引进北疆棉花品种在阿拉尔垦区的适应性分析

2016年从新疆北疆引进12个当地主栽棉花品种在阿拉尔垦区进行品比试验,通过对供试各品种的生育期、丰产性及纤维品质等进行分析。结果表明,部分供试棉花品种(系)在南疆种植生育期明显延长,与阿拉尔垦区中早熟棉花品种生育期相当,综合产量、纤维品质及抗病性表现可以看出,供试棉花品种(系)中第五师的14-3表现较好。     

10个棉花品种比较与筛选试验

为鉴定和评价西北内陆棉区棉花试验联合体新育成的10个棉花品种的丰产性、抗逆性、适应性、纤维品质及综合表现,客观评价参试品种特性与生产应用价值,选择在图木舒克辖区进行品种比较试验,为棉花新品种的推广提供理论依据。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.