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151.
用SSR标记鉴定大豆杂交组合F1的方法研究 总被引:10,自引:0,他引:10
为建立鉴定大豆杂种的方法,采用亲本间有多态性的3对SSR引物,对148个耐盐与盐敏感大豆品种正反交F1植株进行分子鉴定,结果表明,有81.8%的F1为真杂种,且3对多态性SSR引物检测结果一致;在亲本基因型纯合的情况下,采用1对在亲本间有多态性的SSR引物即可对F1真伪进行准确判断;亲本间分子量差异大的SSR位点可用高浓度琼脂糖电泳进行快速鉴定。利用该方法对2007年参加国家大豆区试的大豆杂交种品系H02—286的50粒种子进行纯度鉴定,进一步验证了SSR标记检测杂种真伪的可行性。 相似文献
152.
Flower colour variation across a hybrid zone in Antirrhinum as perceived by bumblebee pollinators 总被引:1,自引:1,他引:0
Emmanuelle Tastard Christophe Andalo Martin Giurfa Monique Burrus Christophe Thébaud 《Arthropod-Plant Interactions》2008,2(4):237-246
To assess if pollinators’ behaviour could explain the maintenance of hybrid zones between different flower colour morphs,
we analyzed flower colour variation in an Antirrhinum hybrid zone using spectrometry and a model of bee perception. Some colours generated by hybridization were not observed in
any Antirrhinum species and even appeared to be rare among angiosperms. Variation in flower colours within the hybrid zone was continuous;
the most similar colours were predicted not to be discriminated from one another in natural foraging situations. However,
when compared at a scale corresponding to bees’ foraging range, some flower colours could be discriminated from all colours
displayed by neighbouring plants. This could affect pollinator behaviour and explain lower visitation rates within the centre
of the hybrid zone. Behavioural studies involving bumblebees and plant mixtures of parental and hybrid flower colours carefully
characterized with appropriate visual models will be necessary to test this hypothesis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Handling editor: Lars Chittka 相似文献
153.
NovW, novU and novS genes have been characterized as dTDP-4-keto-6-deoxy-D-glucose 3-epimerase, C-5 methyltransferase and dTDP-glucose 4-ketoreductase, respectively involved in noviose biosynthetic pathway. We have cloned and expressed the Streptomyces spheroids novWUS genes in S. venezuelae YJ003-OTBP1. This established the function of novWUS and, at the same time, it also proved that the noviosyl derivative of 10-deoxymethynolide(2)/narbonolide(4) obtained from S. venezuelae YJ003-OTBP1 is a novel hybrid antibiotic. 相似文献
154.
Puspa Raj Poudel Ikuo Kataoka Ryosuke Mochioka 《Plant Cell, Tissue and Organ Culture》2008,92(2):147-153
The effect of red- and blue-light-emitting diodes on shoot and root growth of Hybrid Franc grape, a rootstock cultivar, along
with two other grape genotypes, Kadainou R-1 and Vitis ficifolia var. ganebu, were investigated in vitro. Plants cultured under red-light-emitting diodes produced the longest shoots with longer internodes
for all genotypes. The chlorophyll content measured as SPAD value and leaf number per explant were highest on plants cultured
under blue-light-emitting diodes in all the genotypes. Blue light was also responsible for a higher number of stomata in all
the genotypes; however, there was no significant difference in size of stomata in all genotypes under the different light
conditions tested. Different light-emitting diodes did not affect the rooting percentage of Hybrid Franc but red-light-emitting
diodes gave a higher rooting percentage along with higher root numbers for the two other grape genotypes. 相似文献
155.
Swarnalatha Venkateshrao Balan Venkatesh Periakaruppan T. Manoharan 《Nitric oxide》2005,13(4):1153-231
Subunit heterogeneity within a particular subunit in hemoglobin A have been explored with electron paramagnetic resonance spectroscopy using the nitrosyl hemes in Ni-Fe hybrid Hb under various solution conditions. Our previous studies on the crystal structure of NiHb demonstrated the presence of subunit heterogeneity within alpha-subunit. To further cross check this hypothesis, we made a hybrid Hb in which either the alpha- or beta-subunit contains iron, which alone can bind to NO. By this way dynamic exchange between penta- and hexa-coordinated forms within a subunit was confirmed. Upon the addition of inositol hexa phosphate (IHP) to these hybrids, R to T state transition is observed for [alpha(2)(Fe-NO)beta(2)(Ni)] but such a direct transformation is less marked in [alpha(2)(Ni)beta(2)(Fe-NO)]. Hence the bond between N(epsilon) and Fe is fundamental to the structure-function relation in Hb, as the motion of this nitrogen triggers the vast transformation, which occurs in the whole molecule on attachment of NO. 相似文献
156.
Ursodeoxycholic acid (UDCA), a component of bile acid, which is abundant in the gall bladder of bears, has been used in clinical medicine for cholestatic liver diseases. Recently, it was demonstrated that UDCA and its derivative tauroursodeoxycholic acid block apoptotic cell death in both hepatic and non-hepatic cells. Cisplatin, an effective anti-cancer drug, is known to cause sensory neuropathy in patients receiving the drug. In the present study, whether UDCA is effective in blocking cisplatin-induced cell death in mouse hybrid sensory neurons was conducted. N18D3 mouse hybrid sensory neurons exposed to cisplatin were found to undergo apoptotic cell death. Preincubation with UDCA completely blocked cisplatin-induced apoptotic cell death in the sensory neurons, and cisplatin-induced p53 accumulation was suppressed by UDCA treatment. These results indicate that UDCA has a neuroprotective effect on the cisplatin-induced neuronal cell death of sensory neurons via the downregulation of the p53 signaling pathway. 相似文献
157.
Mapping QTLs for defective female gametophyte development in an inter-subspecific cross in Oryza sativa L. 总被引:3,自引:0,他引:3
Y. S. Liu L. H. Zhu J. S. Sun Y. Chen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(8):1243-1251
The embryo-sac is an essential structure for angiosperm reproduction. The cytological and genetic characterization of embryo-sac
sterility was examined in a cross between Oryza sativa ssp. indica cv. ZYQ8 and ssp. japonica cultivar, JX17. The arrest of embryo-sac development was manifested following meiosis in the F1 hybrid. When the megaspore carried the lethal genotype, the nucleus either failed to divide or divided only once, and the
immature embryo-sac degenerated. Abortion of the embryo-sac in the indica-japonica hybrid background was not observed in their original parents, and an effect of cytoplasmic gene(s) on embryo-sac sterility
in the reciprocal F1 hybrids was not detected. Using a rice molecular linkage map based on a doubled haploid (DH) population from the cross of
ZYQ8 /JX17, we mapped quantitative trait loci (QTLs) for the defective development of the female gametophyte in backcross
progenies from the DH lines. The result demonstrated that a polygenic system is involved in both megagametogenesis and postzygotic
isolation in inter-subspecific hybrid rice.
Received: 4 May 2000 / Accepted: 20 September 2000 相似文献
158.
Diplazium with simply pinnate or bipinnatifid leaves. Diplazium wichurae var. wichurae, D. wichurae var. amabile, D. okudairae, and D. pin-faense are sexual diploids (2n=82; n=41II); D.× kidoi and D. × okudairaeoides are sterile diploids (2n= 82; meiosis irregular); D. donianum var. donianum is an apomictic triploid (2n=123; n=123II); D. donianum var. aphanoneuron is a sterile triploid (2n=123; meiosis irregular); D. crassiusculum, D. cavalerianum, D. incomptum, D. longicarpum, and D. pullingeri are sexual tetraploids (2n= 164; n=82II); and D. lobatum is an apomictic tetraploid (2n=164; n=164II). This is the first report of the chromosome numbers of D. lobatum, D. crassiusculum, D. incomptum, D. longicarpum, D. pullingeri, and D. × okudairaeoides, as well as the mitotic chromosome numbers of D. wichurae var. amabile, D. okudairae, D. pinfaense, and D. ×kidoi. The mitotic chromosome number, meiotic behavior, sterility, and allozyme analysis confirm that D. × kidoi and D. × okudairaeoides are hybrids between D. pin-faense and D. wichurae var. wichurae and D. okudairae and D. wichurae var. wichurae, respectively. Diplazium with simply pinnate to bipinnatifid leaves displayed an extraordinary cytological and reproductive complexity: a polyploidal
series with diploids to hexaploids, sexual and apomictic reproduction, and natural hybridization.
Received 14 August 2001/ Accepted in revised form 1 October 2001 相似文献
159.
T Boulikas 《Journal of cellular biochemistry》1992,50(2):111-123
Nuclear matrix organizes the mammalian chromatin into loops. This is achieved by binding of nuclear matrix proteins to characteristic DNA landmarks in introns as well as proximal and distal sites flanking the 5' and 3' ends of genes. Matrix anchorage sites (MARs), origins of replication (ORIs), and homeotic protein binding sites share common DNA sequence motifs. In particular, the ATTA and ATTTA motifs, which constitute the core elements recognized by the homeobox domain from species as divergent as flies and humans, are frequently occurring in the matrix attachment sites of several genes. The human apolipoprotein B 3' MAR and a stretch of the Chinese hamster DHFR gene intron and human HPRT gene intron shown to anchor these genes to the nuclear matrix are mosaics of ATTA and ATTTA motifs. Several origins of replication also share these elements. This observation suggests that homeotic proteins which control the expression level of many genes and pattern formation during development are components of the nuclear matrix. Thus, the nuclear matrix, known as the site of DNA replication, might sculpture the crossroads of the differential activation of origins during development and S-phase and the control of gene expression and pattern formation in embryogenesis. 相似文献
160.
《Current biology : CB》2020,30(20):4033-4046.e8