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41.
Development of SSR markers and construction of a linkage map in jute   总被引:1,自引:0,他引:1  
Jute is an important natural fibre crop, which is only second to cotton in its importance at the global level. It is mostly grown in Indian subcontinent and has been recently used for the development of genomics resources.We recently initiated a programme to develop simple sequence repeat markers and reported a set of 2469 SSR that were developed using four SSR-enriched libraries (Mir et al. 2009). In this communication, we report an additional set of 607 novel SSR in 393 SSR containing sequences. However, primers could be designed for only 417 potentially useful SSR. Polymorphism survey was carried out for 374 primer pairs using two parental genotypes (JRO 524 and PPO4) of a mapping population developed for fibre fineness; only 66 SSR were polymorphic. Owing to a low level of polymorphism between the parental genotypes and a high degree of segregation distortion in recombinant inbred lines, genotypic data of only 53 polymorphic SSR on the mapping population consisting of 120 RIL could be used for the construction of a linkage map; 36 SSR loci were mapped on six linkage groups that covered a total genetic distance of 784.3 cM. Hopefully, this map will be enriched with more SSR loci in future and will prove useful for identification of quantitative trait loci/genes for molecular breeding involving improvement of fibre fineness and other related traits in jute.  相似文献   
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Reddy, A. R. and Das, V. S. R. 1987. Modulation of sucrose contentby fructose 2,6-bisphosphate during photosynthesis in rice leavesgrowing at different light intensities.—J. exp. Bot. 38:828–833. The relationship between the rate of CO2 fixation and sucroseconcentration in the leaves of rice (Oryza sativa L.) grownat different light intensities was investigated. Maximum sucrosecontent coincided with maximum rates of CO2 fixation, achievedat a photon flux density of 1600 µmol m–2 s–1.The levels of sucrose and fructose 2,6-bisphosphate were alsocompared in the leaves under different light intensities. Fructose2,6-Msphosphate accumulated during growth at low light. Theactivity of fructose-6-phosphate 2-kinase was high in the leavesgrown at low light while that of fructose-2,6-bisphosphatasewas low. The activities of phosphoglucose isomerase and phospho-glucomutasewere slightly increased by growth at low light The activitiesof UDP glucose pyrophosphorylase were adversely affected invitro with increased concentrations of fructose 2,6-bisphosphatewhile those of sucrose phosphate synthase were moderately affected.Phosphoglucose isomerase and phosphoglucomutase were activatedby fructose 2,6-bisphosphate (8-0 mmol m–3) by 12-15%.The results suggested that low light intensities during growthresult in an accumulation of fructose 2,6-bisphosphate whichmodulates the key enzymes of sucrose biosynthesis thus regulatingcarbon flow under conditions of limited photosynthesis. Key words: Oryza sativa, photosynthesis, sucrose synthesis, fructose 2,6-bisphosphate, light  相似文献   
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Scutellum extracts of dry unaged and differentially aged wheatseeds showed appreciable and ß amylase activities,these being higher in unaged and lower in aged seeds. This indicatesthat scutellar amylase may remain long-lived in seeds. Duringgermination of both unaged and aged seeds an increase in scutellaramylase (particularly ß) occurs. Initiation of thisgermination associated increase in amylase activity, however,was found to occur relatively late during imbibition. Further,while scutellar amylase increased considerably during imbibitionin unaged seeds, in differentially aged seeds the increase wassmall. This also contributes to the reduced scutellar amylaseactivities in aged seeds. Triticum aestivum L., wheat, naturally aged, accelerated aged, unaged, germination, scutellar and ß amylase  相似文献   
44.
Treatment of S-sufficient or S-deficient Chlorella pyrenoidosacells with NaHSO3, during an 8-h period in the light, significantlydecreased their chlorophyll and dry matter contents when thecells were incubated in the presence or absence of SO42+. Incontrols lacking HSO3, when the starting pH was 7.5,dry matter and chlorophyll contents increased slightly, whereasno significant changes in either occurred at a starting pH of3.0 when the cells and medium contained SO4. In the dark,at both pH 3.0 and 7.5, dry matter and chlorophyll contentsdecreased slightly. Bisulphite treatment in the dark causedlittle decrease of either dry matter or chlorophyll when cellsand medium contained SO42–. However, in its absence, drymatter decreased markedly, but there was little change of chlorophyllcontent in the dark. The interactions between HSO3 asa source of S and as an inhibitor of growth and chlorophyllformation are discussed in the context of the changes inducedby light and alternative sources of S. Overall, the harmfuleffects of HSO3 outweigh any role it has as a sourceof S, since its effects are ameliorated by SO42–.  相似文献   
45.
cDNA clones encoding the entire porcine alpha s2-casein message were isolated and sequenced. The porcine alpha s2-casein cDNA is 1093 bp, excluding the poly(A) tail, in length and encodes a preprotein of 235 amino acids.  相似文献   
46.
R. S. RANA  P. DEY  A. DAS 《Cytopathology》1997,8(2):108-113
Fine needle aspiration (FNA) cytology of extra-adrenal paragangliomas We studied nine histologically proved cases of extra-adrenal paragangliomas. Of these, eight cases were correctly diagnosed preoperatively by FNA cytology. Salient cytological features included clusters and discretely scattered cells, with occasional acinar configuration. The cells showed moderate to abundant slightly basophilic cytoplasm with ill-defined margins and round to oval nuclei with mild to marked nuclear pleomorphism. Fine reddish intracytoplasmic granules were also noted (six cases). Cytological features along with clinical data are quite diagnostic of paragangliomas. A correct preoperative cytological diagnosis helps to prevent undue surgical complications. Cytologie par ponction aspiration à l'aiguille fine des paragangliomes extra-surrénaliens Nous avons étudié 9 cas de paragangliomes extra-surrénaliens histologiquement prouvés. Huit cas sur 9 ont été correctement diagnostiqués, à titre pré-opératoire, par cytologie par ponction aspiration à l'aiguille fine. Les caractéristiques cytologiques principales sont la présence d'amas, une dispersion cellulaire modérée et d'occasionnelles formations acineuses. Les cellules comportent un cytoplasme légèrement basophile, moyennement à très abondant, avec des limites mal définies ainsi qu'un noyau rond ou ovale, dont le pléomorphisme nucléaire est modéré ou plus nettement marqué. Le présence de fines granulations rougeâtres intra-cytoplasmiques a également été notée (6 cas). Ces caractères cytologiques, associés aux données cliniques, permettent pratiquement le diagnostic des paragangliomes. Un diagnostic cytologique pré-opératoire correct favorise la prévention des complications chirurgicales indésirables. FNP extraadrenaler Paragangliome Neun histologisch gesicherte Fälle extraadrenaler Paragangliome werden vorgestellt. Präoperativ waren 8 der Fälle zytologisch durch FNP richtig diagnostiziert worden. Charakteristisch waren Einzelzellen und z.T. azinäre Verbände. Die Zellen zeigten mässig bis reichlich, leicht basophiles, unscharf begrenztes Zytoplasma und rund-ovale Kerne mit leichter bis ausgeprägter Pleomorphie. In 6 Fällen lagen feine, rote Granula im Zytoplasma vor. Das zytologische Bild in Zusammenschau mit den klinischen Daten erlaubt eine sichere Diagnose. Auf diese Weise können die operativen Risiken vermindert werden.  相似文献   
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Abstract Multi‐locus microsatellite typing (MLMT) has been employed to infer the population structure of Phlebotomus papatasi (Scopoli) (Diptera: Psychodidae) sandflies and assign individuals to populations. Phlebotomus papatasi sandflies were collected from 35 sites in 15 countries. A total of 188 P. papatasi individuals were typed using five microsatellite loci, resulting in 113 different genotypes. Unique microsatellite signatures were observed for some of the populations analysed. Comparable results were obtained when the data were analysed with Bayesian model and distance‐based methods. Bayesian statistic‐based analyses split the dataset into two distinct genetic clusters, A and B, with further substructuring within each. Population A consisted of five subpopulations representing large numbers of alleles that were correlated with the geographical origins of the sandflies. Cluster B comprised individuals collected in the Middle East and the northern Mediterranean area. The subpopulations B1 and B2 did not, however, show any further correlation to geographical origin. The genetic differentiation between subpopulations was supported by F statistics showing statistically significant (Bonferroni‐corrected P < 0.005) values of 0.221 between B2 and B1 and 0.816 between A5 and A4. Identification of the genetic structure of P. papatasi populations is important for understanding the patterns of dispersal of this species and to developing strategies for sandfly control.  相似文献   
50.
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