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121.
Factors affecting shoot regeneration from hypocotyl segments of spinach (Spinacia oleracea L.) were investigated. When expiants were cultured on medium containing 10 mg/l IAA for 7 weeks, 3 out of 9 cultivars showed relatively high shoot regeneration response (15 – 35%). The other PGRs tested had no effect on shoot regeneration. However, the transfer of explants from auxin-containing medium to auxin-free medium 20 d after culture induced shoot formation from expiants cultured on media containing each of the auxin sources tested individually. By applying this short term auxin treatment, more than 80% shoot regeneration was obtained on medium containing 5–20 mg/l 5,6-Cl2-IAA, compared to less than 30% with 10–20 mg/l IAA treatment.Abbreviations BAP
6-benzylaminopurine
- NAA
1naphthaleneacetic acid
- IAA
indole-3-acetic acid
- 2,4D
2,4-dichlorophenoxyacetic acid
- 5,6-Cl2-IAA
5,6dichloro-indole-3-acetic acid
- PGR
plant growth regulator
- A-PGR
auxin-like plant growth regulator 相似文献
122.
Using flow cytometry, we measured the nuclear DNA contents of all known taxa in Hepatica. Nuclear DNA content of Hepatica falconeri (diploid, crenate leaf lobes) was significantly lower than that of diploid entire species. Among the tetraploid species, crenate species had lower DNA contents than the entire taxon H. nobilis var. pubescens. The DNA content of the tetraploid species was more than double that of the diploid species among the same leaf-type groups. 相似文献
123.
Nimura M Kato J Mii M Morioka K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,106(7):1164-1170
Reciprocal interspecific crosses were carried out between six lines of Dianthus caryophyllus L. and one line of Dianthus japonicus Thunb. Although no seed was set when D. japonicus was used as the seed parent, six seedlings were successfully obtained from 2,380 immature ovules by applying the embryo-rescue technique. However, they showed seed parent-like morphology and no evidence for the hybridity by flow cytometry and RAPD analyses. When six lines of D. caryophyllus were used as seed parents, a total of 192 seedlings were successfully obtained without using the embryo-rescue technique. Among these seedlings, 12 out of 25 progenies obtained from the carnation line '98sp1651' were confirmed to be the hybrids. The remaining 13 progenies of this line, and the total 167 progenies obtained from the other carnation lines, had carnation-like morphology without any evidence of hybridity by flow cytometry and RAPD analyses. The progenies confirmed as hybrids had intermediate characters of the parents with respect to leaf width and flower size, but they had a uniform flower color, reddish purple, which was different from that of either parent. Since the hybrids obtained in the present study have some profitable characters such as vigorous growth in summer time, upright robust stem, broad leaves and early flowering, they are expected to be used for the breeding of carnation which is suitable for growing under the Japanese climate. 相似文献
124.
Kanato K Hosen N Yanagihara M Nakagata N Shirakata T Nakazawa T Nishida S Tsuboi A Kawakami M Masuda T Oka Y Oji Y Ijpenberg A Hastie ND Sugiyama H 《Biochemical and biophysical research communications》2005,326(4):836-843
It is well known that the Wilms' tumor gene WT1 plays an important role in cell proliferation and differentiation, and in organ development. In this study, to examine the role of the WT1 gene in lineage determination, fetal liver cells from LacZ-transgenic mice, in which WT1 expression was marked by the expression of the LacZ gene driven by WT1 promoter, were FACS-sorted according to LacZ expression of high (LacZ(++)) or undetectable (LacZ(-)) levels, which paralleled endogenous WT1 expression levels. LacZ(++) fetal liver cells were enriched by hepatocyte and endothelial progenitor cells. These results indicated that WT1 expression is a common marker of both hepatocyte and endothelial progenitors. These results also implied a role of the WT1 gene in lineage determination. 相似文献
125.
We have achieved the symbiotic cultivation of an apparently achlorophyllous orchid, Epipogium roseum Lindl., with a mycorrhizal fungus isolated from an underground organ of this orchid. Although the seed germination rate was
extremely low, subsequent growth from protocorm to flowering was induced in a medium containing volcanic soils and sawdust.
Stolons elongated from each protocorm, and rhizomes were formed at certain intervals on the stolons. Some of the rhizomes
developed into a coralloid form, and tubers were formed from the coralloid rhizomes. The coralloid rhizomes degenerated concurrently
with maturation of the tubers. Six months after seed sowing, around 80 tubers were produced from a single protocorm. An inflorescence
appeared from each of the large tubers, and the process to flowering was observed in one of these. Consequently, the developmental
processes from seed to flowering in E. roseum was clearly revealed in this study. 相似文献
126.
Osteosarcoma Cells Enhance Angiogenesis Visualized by Color‐Coded Imaging in the In Vivo Gelfoam® Assay 下载免费PDF全文
127.
Yu-Shih Lin Kuo-Yen Wei In-Tian Lin Pai-Sen Yu Hong-Wei Chiang Chen-Yin Chen Chuan-Chou Shen Horng-Sheng Mii Yue-Gau Chen 《Marine Micropaleontology》2006,59(3-4):153-170
The Holocene Pulleniatina Minimum Event (PME) is characterized by a very low abundance of the planktonic foraminifer Pulleniatina obliquiloculata between 4.5 and 3 ka. The PME occurs widely in the Okinawa Trough and the South China Sea, and can be correlated throughout this area; it has been related to variability in the Kuroshio current. To further explore the nature of the PME, we studied cores obtained from the southern Okinawa Trough and the upper reaches of the Kuroshio current. Faunal census data indicate that all cores record the PME between 4.5 and 3 ka. The relative abundance of Neogloboquadrina dutertrei is negatively correlated to that of P. obliquiloculata in the southern Okinawa Trough, but not in the sites at the upper reaches. Mg/Ca and δ18O measurements on Globigerinoides ruber shells from the southern Okinawa Trough indicate that there was no change in sea surface temperature or sea surface salinity during the PME. The vertical structure of the water column as reconstructed by multispecies δ18O and δ13C profiles shows no consistent anomalies in the southern Okinawa Trough and western Philippine Sea during the PME. These observations suggest that: (1) the PME was not restricted to marginal seas, but widespread in the western North Pacific. (2) The high abundance of N. dutertrei during the PME in the Okinawa Trough may be a result of higher food-availability in the absence of P. obliquiloculata. (3) No distinctive, consistent anomalies in the paleoceanographic proxies are associated with the PME, implying there were no changes in hydrography and productivity. The absence of a linkage between faunal variation and paleoceanographic proxies indicates that we do not yet understand what causes changes in planktonic foraminiferal assemblages. This lack of understanding implies that we cannot always trust fauna-based paleothermometry at millennial timescales. 相似文献
128.
The use of antibiotic or herbicide resistant genes as selection markers for production of transgenic plants and their continuous
presence in the final transgenics has been a serious problem for their public acceptance and commercialization. MAT (multi-auto-transformation)
vector system has been one of the different strategies to excise the selection marker gene and produce marker-free transgenic
plants. In the present study, ipt (isopentenyl transferase) gene was used as a selection marker gene. A chitinase gene, ChiC (isolated from Streptomyces griseus strain HUT 6037) was used as a gene of interest. ChiC gene was cloned from the binary vector, pEKH1 to an ipt-type MAT vector, pMAT21 by gateway cloning and transferred to Agrobacterium
tumefaciens strain EHA105. The infected tuber discs of potato were cultured on hormone- and antibiotic-free MS medium. Seven of the 35
explants infected with the pMAT21/ChiC produced shoots. The same antibiotic- and hormones-free MS medium was used in subcultures of the shoots (ipt like and normal shoots). Molecular analyses of genomic DNA from transgenic plants confirmed the integration of gene of interest
and excision of the selection marker in 3 of the 7 clones. Expression of ChiC gene was confirmed by Northern blot and western blot analyses. Disease-resistant assay of the marker-free transgenic, in
vitro and greenhouse-grown plants exhibited enhanced resistance against Alternaria solani (early blight), Botrytis cinerea (gray mold) and Fusarium oxysporum (Fusarium wilt). From these results it could be concluded that ipt gene can be used as a selection marker to produce marker-free disease-resistant transgenic potato plants on PGR- and antibiotic-free
MS medium. 相似文献
129.
Waleerat Banyai Chalermpol Kirdmanee Masahiro Mii Kanyaratt Supaibulwatana 《Plant Cell, Tissue and Organ Culture》2010,103(2):255-265
Transgenic plants of Artemisia annua L., a medicinal plant that produces the compound artemisinin which has an anti-malarial activity, were developed following
Agrobacterium tumefaciens-mediated transformation of leaf explants. A. tumefaciens strain EHA105 carrying either pCAMBIA1301 or pCAMBIAFPS was used. Both plasmids harbored the hygromycin phosphotransferase
II (hptII) gene as a selectable gene, but the latter plasmid also harbored the gene encoding for farnesyl pyrophosphate synthase
(FPS), a key enzyme for artemisinin biosynthesis. Shoot regeneration was observed either directly from leaf sections or via intervening
callus when explants were incubated on solidified Murashige and Skoog (MS) (1962) medium containing 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 1 mg l−1 N6-benzyladenine (BA), 30 mg l−1 meropenem and 10 mg l−1 hygromycin. Applying vacuum infiltration dramatically increased transformation efficiency up to 7.3 and 19.7% when plasmids
with and without FPS gene were used, respectively. All putative transgenic regenerants showed positive bands of hptII gene following Southern blot analysis. Expression of FPS was observed in all transgenic lines, and FPS over-expressed lines exhibited higher artemisinin content and yield, of 2.5- and 3.6-fold, respectively, than that detected
in wild-type plants. A relatively high correlation (R
2 = 0.78) was observed between level of expression of FPS and artemisinin content. However, gene silencing was detected in some transgenic lines, especially for those lines containing
two copies of the FPS transgene, and with some lines exhibiting reduced growth. 相似文献
130.