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1.
利用自花结实的4D缺体小麦作母本,与中2、中5及中1001等八倍体小偃麦杂交,获得的杂种F1植株除4D缺体×中5育性极低外,其余组合略低于普通小麦×八倍体小偃麦的自交结实率。杂种F1体细胞2n=48。4D缺体×中2的F1花粉母细胞减数分裂MI染色体配对的平均构型为18.81(15-22)Ⅱ+0.57(0-3)Ⅲ+0.11(0-2)Ⅳ+8.23(6-10)Ⅰ。观察结果同时表明:(1)单价体的分布在每个PMC中以8为众数;(2)单价体之中的两个在多数的PNCs中能形成次级联合配对,说明4D与4E染色体具有部分同源关系;(3)杂种F1多数花粉母细胞中多价体的出现表明八倍体小偃麦中E染色体组具有促进部分同源染色体配对的基因。  相似文献   

2.
利用聚丙烯酰胺凝胶电泳法对人工合成的[AG]复合染色体组的异源四倍体与[AD]复合染色体组的陆地棉、海岛棉、夏威夷棉、黄褐棉的种间杂种F1及其亲本进行了过氧化物酶同工酶和细胞色素氧化酶同工酶分析,并对三元杂种[A2×G1] ×[AD]1及其亲本进行了核型分析。结果表明:(1)异源四倍体的基因转移到了杂种后代,并得以表达;( 2)三元杂种[A2 × G1] ×[AD]1的核型公式为 2n= 4x= 52= 2M + 44m(SAT)+6sm(SAT),属于1B类型。  相似文献   

3.
戚存扣  仲裕泉 《作物学报》1995,21(6):717-722
从甘蓝型油菜品种“3-63-4-5-1”与埃塞俄比亚芥品种“Dodolla”杂种F1植株开放受粉获得的F2群体中筛选出一株半不育、矮杆、甘蓝型油菜类型植株,经连续4个世代自交、分离鉴定出一个二体附加系“92I1096”。细胞学观察结果,其根尖细胞染色体数2n=40,比其母本甘蓝型油菜(2n=38)多两条额外染色体。花粉母细胞(PMCs)减数分裂中期(MI)染色体构型平均为0.47I+19.77Ⅱ,  相似文献   

4.
抗BYDV小麦——中间偃麦草易位系α-淀粉酶2同工酶的研究   总被引:12,自引:2,他引:10  
陈孝  钱幼婷 《作物学报》1998,24(1):16-20
对抗大麦黄矮病毒病的普通小麦--中间偃麦草易位系F94631和F94885-2进行抗性和α-淀粉酶2同工酶电泳图谱的研究,证明抗性基因和控制α-淀粉酶2形成的结构基因α-Amy-Ag2(α-Amy-X2)均位于中间偃麦草第76组染色体长臂上。这两个基因都呈显著遗传性。α-Amy-X2控制形成二条α-淀粉酶2特异酶带,可认为是7Ai-1长臂的生化标记,经BYDV抗性和α-淀粉酶2遗传分析,推断这两个  相似文献   

5.
棉属分类及其染色体组研究进展   总被引:1,自引:0,他引:1  
本文综述了棉属(Gossypium)分类和棉属梁色体组研究的最新进展。全文共分5个部分:(1)棉属分类,重点介绍了Fryxell的棉属分类方案以及最近几次较大的修订情况,并列出了包括47个种、4个亚种在内的棉属最新分类名录;(2)棉属染色体组。介绍了棉属细胞学及染色体组研究的发展历史,把棉属分为A、B、C、D、E、F和G7个二倍体染色体组和AD1个异源四倍体复合染色体组;(3)棉属染色体核型分析。介绍了棉属染色体核型研究的意义和内容;(4)棉属染色体组的演化。介绍了棉属染色体组演化的四种不同观点,讨论了AD复合染色体组供体问题;(5)讨论。讨论了棉属分类以及比克氏棉(G.bickii)和大萼组(sect.Grandicalyx)棉种的染色体组归属问题。  相似文献   

6.
三个棉属种间杂种花粉母细胞减数分裂观察   总被引:2,自引:0,他引:2  
对棉属3个种间杂种TM-1×石系亚1号、TM-1×辣根棉和TM-1×瑟伯氏棉花粉母细胞的减数分裂进行了观察。结果表明,3个杂种多数花粉母细胞中期Ⅰ的染色体构型为13Ⅱ+13Ⅰ。二价体联会成环状、棒状或V型。TM-1×辣根棉杂种的二价体联会较紧密。杂种除正常的染色体组AA和DD联会外,还发生AD联会及出现多价体。中期Ⅰ单价体大部分分散于赤道板两侧,并较早移向两级。个别二价体也不排列在赤道板上。二价体向两极移动时常形成染色体"桥",使这些染色体移动速度减慢,导致细胞分裂不同步。此外,在第一次分裂和第二次分裂中都能看到落后染色体、远离大多数染色体的零星染色体、孤立的染色体群等现象。后期Ⅱ的花粉母细胞可形成较多的核仁。在四分孢子期,3个种间杂种既产生四分体,也形成二、三、五、六乃至十分体。TM-1×石系亚1号、×辣根棉、×瑟伯氏棉杂种的四分体数分别为70.2%、63.1%和35.1%。  相似文献   

7.
棉花遗传转化和植株再生的研究   总被引:15,自引:1,他引:15  
利用农杆菌(GUS基因(β-葡萄糖苷酸酶基因)为标记基因,NPTⅡ为选择基因)用共培法对棉花下胚轴切段直接转化,在0.1mg/L2,4-D和0.1mg/LKT的MS的培养基上共培48h,转移到加头孢霉素500mg/L和50~100mg/L卡那霉素的上述培养基中诱导和筛选抗性愈伤组织,70~80天计算愈伤组织的诱导频率,并有组织化学定位法检测GUS基因的表达,统计转化频率,结果表明:平均出愈率为40  相似文献   

8.
Yamam.  K 《小麦研究》1997,18(3):36-36,F003,F004
为了确定半矮秆基因Rht1和Rht2是否影响花粉培养的胚诱导,比较了双端体的中国春4B和4D染色体和半矮秆等位系的两个位点与Rht1和Rht2位点等位基因的差异。4B和4D染色体臂的缺失很少影响胚诱导。Rht1和Rht2基因两个位点都没降低胚诱导。结果表明,在双单倍体育种程序中,通过花粉培养方法改良携带有这些半矮秆基因的品种是毫无问题。  相似文献   

9.
同工酶基因数量化方法对亚洲栽培稻的分类研究   总被引:16,自引:0,他引:16  
孙新立  才宏伟 《作物学报》1996,22(6):693-699
采用将同工酶基因数量化方法对水稻籼、粳分类进行研究,其过程与结果如下:(1)通过对539份亚洲栽培稻材料的多位点同工酶分析,发现其中6个同工酶位点即AMP-2,Cat-1,Mal-1,Acp-2,Est-10具有更好的籼、粳判别效果。用6个位点上的DJ值计算出每份材料的PJ值(即材料属于粳和籼的可能性),发现539份材料的PJ值分类结果与程氏形态指数分类法的结果符合性很好,仅有少数例外;(2)对6  相似文献   

10.
研究表明,浸种棉苗SOD(超氧物歧化酶)、POD(过氧化物酶)、CAT(过氧化氢酶)活性升高;MDA(丙二醛)含量及电导率降低;Pro、可溶性总糖和叶绿素含量增加;根和叶TTC(氯化三苯基四氮唑)还原率同步增大,电导率同步降低。田间试验结果在明,座桃率提高,霜前花增多,稳产高产优质。棉苗喷药可抵抗-2℃(5h)~-3℃(3h)~-4℃(3h)~-5℃(1h)长达12小时不受冻害,这种抗寒力可保持1个月。  相似文献   

11.
Jens Jensen 《Euphytica》1979,28(1):47-56
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.  相似文献   

12.
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.  相似文献   

13.
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...  相似文献   

14.
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.  相似文献   

15.
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...  相似文献   

16.
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.  相似文献   

17.
T. Visser  E. H. Oost 《Euphytica》1981,30(1):65-70
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.  相似文献   

18.
[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...  相似文献   

19.
E. Keep 《Euphytica》1986,35(3):843-855
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).  相似文献   

20.
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.  相似文献   

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