草莓组织培养与快速繁殖技术

以"红颜"草莓的匍匐茎尖为外植体,选择附加不同激素组合的MS培养基为诱芽培养基和继代培养基,以1/2MS为生根培养的基本培养基,对"红颜"草莓的组织培养及快繁进行研究。结果表明:草莓茎尖在MS+6-BA2.0 mg/L+NAA0.2 mg/L培养基上能很好地诱导不定芽形成,其诱导率高达80%;继代增殖培养基为MS+6-BA2.0 mg/L+IBA0.5 mg/L+IAA0.5 mg/L+GA1.0 mg/L时增殖系数较高;生根培养基为1/2MS+IAA0.5 mg/L时生根率可达99%,移栽至田间后,成活率高且匍匐茎繁殖能力强。     

魔芋不同外植体组培快繁及其再生体系的研究

本研究以魔芋不同外植体为实验材料,建立了魔芋离体培养快速繁殖的再生体系,为以后魔芋基因工程进行品质改良奠定了基础。以不同基因型魔芋为实验材料,研究魔芋不同外植体在不同的培养基中诱导不定芽再生的频率。魔芋不同基因型外植体在含适宜6BA、NAA等激素的培养基中形成愈伤组织的难易程度不同,愈伤组织诱导形成不定芽的能力强弱也不一样;不同基因型魔芋外植体的不定芽诱导率最高的是块茎幼叶茎段;对魔芋的块茎、茎段和幼叶来说最适合的培养基配方是MS+6-BA 2.5 mg/L+NAA 0.05 mg/L,不同培养基诱导不定芽的能力是块茎茎段幼叶,其中,魔芋块茎和茎段的再生能力较强。最合适的生根培养基是MS+1.0 NAA。本研究成功的建立了魔芋不同外植体离体培养再生途径,并获得再生植株。     

辣椒离体再生体系研究

以5个辣椒（Capsicum annuum L.）品种（系）为材料,针对不同基因型、苗龄、外植体种类、激素组合等因素对辣椒植株离体再生的影响进行了较为系统的研究,从“农城椒2号”、“农城椒3号”、“0127”、“0159”、“0171”等5个辣椒品种（系）中筛选出“农城椒2号”、“0127”、“0171”3个再生能力较强的基因型。确定了辣椒离体再生最适外植体为子叶,最适苗龄为12~14d。筛选出高效不定芽分化培养基（MS＋3%蔗糖＋0.6%琼脂＋5.0mg/L BA＋0.5~1.0mg/L IAA）,其不定芽诱导率可达98%。诱导出的不定芽转入MS＋3%蔗糖＋0.6%琼脂＋3.0mg/L BA＋1.0mg/L IAA＋2.0mg/L GA3＋10.0mg/L AgNO3 芽伸长培养基,不定芽伸长率最高可达47.1%。不定芽伸长后在MS＋3%蔗糖＋0.6%琼脂＋0.2mg/L IAA＋0.1mg/L NAA生根培养基上诱导不定根。待其长成发达根系后移栽大田成苗,建立了辣椒高效植株再生体系。     

菊花“帅旗”组织培养技术研究

以带芽的菊花“帅旗”茎段为外植体，在附加不同浓度植物生长调节剂2,4-D、6-BA和IBA的MS基本培养基上诱导培养，通过器官直接发生途径获得再生植株。结果表明：菊花“帅旗”茎段外植体在无菌条件下用75%酒精消毒30 s，再用0.1%的升汞消毒9 min的污染率最低；茎段在添加不同生长调节剂配比的培养基中再生不定芽的能力不同；丛生芽诱导的最佳培养基为MS+6-BA 0.3 mg/L+2,4-D 0.3 mg/L+IBA 0.1 mg/L；最佳生根培养基为1/2 MS+2,4-D 3.00 mg/L+IBA 0.60 mg/L。     

裕民无刺红花的组织培养和植株再生

以裕民无刺红花成熟种子胚轴为外植体,在含BA(0.5mg/L)和NAA(1.5mg/L)的MS培养基上每个外植体均可诱导出若干个不定芽,平均每个外植体可产生4个不定芽,健壮的不定芽经过伸长、生根后可移栽成活.本试验利用裕民无刺红花品种获得了其再生植株,为其遗传转化和多倍体的诱导奠定了基础.     

大豆不同基因型胚尖不定芽的诱导及对抗生素的敏感性

以大豆胚尖为外植体,在MS+3.0mg/L6BA上培养诱导8个基因型产生不定芽,筛选适合于胚尖再生系统的大豆基因型。同时,测定吉林40在诱导胚尖不定芽时对卡那霉素和头孢霉素的耐受性。结果表明,在8个大豆基因型中,2个基因型的不定芽诱导率大于90%,综合考虑不定芽诱导率和芽数两个性状,吉林40和黑农37适合于大豆胚尖不定芽再生系统。在培养基中加入卡那霉素或头孢霉素时,随着抗生素浓度的增加,胚尖不定芽诱导率急剧下降。经方差分析,卡那霉素和头孢霉素对大豆胚尖不定芽诱导率和芽数均有明显的抑制作用。在培养基内加入200mg/L卡那霉素或300mg/L头孢霉素时,胚尖不定芽诱导率和芽数显著地低于对照。在胚尖再生系统遗传转化中,建议以200mg/L卡那霉素作为抗性筛选浓度,使用头孢霉素作为脱菌剂时,浓度低于300mg/L不会降低大豆胚尖不定芽的诱导率和芽数。     

辽东楤木愈伤组织诱导及增殖技术研究

以辽东楤木茎尖、幼叶、嫩茎、休眠芽为外植体,以MS为基本培养基,附加不同种类和浓度的植物生长调节物质诱导丛生芽及再生植株,筛选出适合于辽东楤木组织培养的系列培养基配方.结果表明,愈伤组织诱导的最佳培养基为:MS+6-BA 2.0mg/L+NAA 0.1mg/L(或IAA0.2mg/L),幼叶为愈伤组织诱导的理想外植体,30d继代一次分化效率较高,达到73%;不定芽分化的最佳培养基为MS+6-BA1.0～1.5mg/L十IAA0.1～0.15mg/L+NAA0.1～0.15mg/L;不定芽生根的最佳培养基为1/2MS+NAA0.5mg/L;按1∶1混配的蛭石与草炭为试管苗移栽最适基质.     

罗汉果遗传转化受体再生体系的建立及发根农杆菌转化初探

以罗汉果品种“青皮果”试管苗的茎段和叶片为外植体,研究适合于遗传转化的受体再生系统,并进行了发根农杆菌转化的初步研究。试验结果表明茎段的再生能力强于叶片,且对农杆菌敏感,是进行遗传转化合适的受体材料。在MS基本培养基附加BA 1mg/L、KT 1mg./L、NAA 0.2mg./L、蔗糖30 mg/L培养基中,20d龄的茎段不定芽诱导率为100%,平均每个外植体诱导的不定芽数达到9.7个,移苗成活率90%以上;外植体培养前的割伤处理有利于提高出芽数;发根农杆菌转化茎段诱导出毛状根。罗汉果毛状根的诱导和培养将为罗汉果药用成分的研究和开发提供新的途径。     

大花萱草不定芽直接诱导和植株再生的研究

本研究旨在不通过愈伤途径，直接诱导大花萱草不定芽，并建立相应的植株再生技术体系。实验以大花萱草‘32-1’幼芽为外植体，配制不同激素和活性炭的培养基，考察各因素对大花萱草植株再生的影响。结果表明：不同激素配比对大花萱草‘32-1’初代培养、继代增殖和生根培养影响差异显著。最适初代培养基为MS+6-BA 3.0 mg/L+NAA 2.0 mg/L，启动率和增殖系数分别是100.00%和5.60，可直接诱导出不定芽；最适增殖培养基为MS+6-BA 2.0 mg/L+NAA 0.5 mg/L，增殖系数为3.47；最佳生根培养基为1/2MS+NAA 1 mg/L+AC 2 g/L。     

宁夏枣树花药离体培养再生体系的建立

采用宁夏3个特色枣树品种的花药为外植体,探索MS培养基中不同激素、激素的不同浓度配比对愈伤组织诱导、不定芽分化的影响,建立其愈伤组织诱导及不定芽再生体系。结果表明,细胞分裂素6-BA对宁夏枣树胚性愈伤组织诱导起重要作用,AgNO3对愈伤组织分化不定芽影响显著。经过正交试验分析得出,最佳诱导培养基为MS+6-BA 1.0 mg/L+2,4-D1.0 mg/L+IBA 0.4 mg/L;最佳分化培养基是：MS+6-BA 1.5 mg/L +IBA 0.6 mg/L +AgNO3 0.5 mg/L。在最佳诱导培养基中灵武长枣诱导率最高,达89.0%,在最佳分化培养基中同心圆枣分化率最高,达88.0%。     

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.