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11.
V. S. Gupta M. S. Dhar B. G. Patil G. S. Narvekar S. R. Ra Wat P. K. Ranjekar 《Journal of biosciences》1990,15(4):261-269
Rice long repetitive DNA (9–20 kbp) reassociating at Cot 50 M.s was cloned in pBR325. Out of several recombinants (Camr Ampr Tets), only a few were selected randomly for further characterization. The insert size in all these clones was 3–4 kbp. Restriction
enzyme analysis showed the absence ofEcoRI andBclI sites, presence of a singlePstI andPvuII site and multiple sites forAluI in 3 clones namely pRLl, pRL7 and pRL10.
TheBamHI-PstI fragment of about 0.4 kbp in the pRL7 insert DNA (pRL7-0.4 kbp) was subcloned in M13mpl8 and partially sequenced using Sanger’s
dideoxynucleotide chain termination method. Dot matrix comparison of this sequence with rice rDNA sequences revealed low homology
with the 25 S rDNA sequence of rice, however, hybridisation did not indicate any homology. 相似文献
12.
A highly efficientin vitro regeneration methodology for mature chutese tallow tree (Sapium sebiferum Roxb.) has been developed. Shoot segments cultured on MS medium supplemented with 7.5 µM NAA produced light green callus. Optimum shoot differentiation resulted when callus was transferred to MS medium with 1 µM BA and 0.25 µM NAA. Shoot forming ability of callus was higher on MS medium compared to B5, half-MS or WPM. A continuous shoot harvest system at four-week intervals was established. Shoot yield continued for six months without loss of vigour. Regenerated shoots were rooted by culturing on half strength agar-gelled MS medium containing 1 µM IBA. Rooted plantlets were transferred to 1:1 soil vermiculite mixture and acclimatized with 67 % survival rate. Fully acclimatized plants were planted in the field, and performance is being evaluated.Abbreviations 2, 4- D
2, 4-dichlorophenoxyacetic acid
- NAA
1 - napthaleneacetic acid
- BA
benzyladenine
- Kn
kinetin
- 2-ip
6 - (, -dimethylallylamino)-purine
- IBA
indole-3-butyric acid
- WPM
woody plant medium (1980)
- MS
Murashige and Skoog (1962) medium
- B5
Gamborg et al's medium (1968) 相似文献
13.
Dipanwita Bhattacharya T.K. Dhar K.A.I. Siddiqui E. Ali 《Journal of applied microbiology》1994,77(2):129-133
The production of phaseolinone, a phytotoxic metabolite of Macrophomina phaseolina in infected Phaseolus mungo seeds grown on soil, was estimated by enzyme-linked immunosorbent assay and HPLC. The degree of inhibition of seed germination correlated well with the amount of toxin produced; 50% inhibition was observed at a toxin level of 2.1 μg g-1 of wet tissue. A comparison of the toxin-producing ability of nine isolates of the fungus obtained from different hosts and localities showed that the strain MPK'83 produced a significantly larger amount of the toxin, both in liquid culture and in infected seeds. The virulence of the isolates was related to their ability to produce phaseolinone. 相似文献
14.
15.
S. K. Dhar 《Inorganica chimica acta》1995,240(1-2):609-614
Cyclic voltammetry at a micro electrode of Co(II) salen, Fe(II) salen, electrode generated Fe(II)(acac)2, Fe(II) (salicylaldehyde)2, Fe(II) (salicylaldoxime)2, Fe(II) (bipy)3, Fe(II) (bipy)2, Co(II) (bipy)3, Co(II) (benzacac)2, and electrode generated Co(acac)2 in oxygen saturated aprotic solvents show positive shift of the O2 sigmoidal wave, as well as enhancement of the limiting current in the case of the first five compounds. In the case of Co(II) (bipy)3 the slope of the sigmoidal wave due to O2 becomes more positive, while for the other two Co(II) complexes there is no change except a small decrease in the wave height. The data are used to correlate and predict the O2 binding properties of the chelates in solution. The data for the diketone complexes of Co(II) indicate absence of any direct association, which is in line with the interpretation offered in the literature on the mechanism of their catalytic role in the O2 oxidation of substrates. The mechanism of the autoxidation of dimethylformamide in the presence of Fe(III) (bipy)3 and Cu(II) (bipy)2 is elucidated by the observation that these higher valent compounds are reduced to their next lower oxidation state by DMF. 相似文献
16.
17.
Analysis of genetic diversity in common loon Gavia immer using RAPD and mitochondrial RFLP techniques 总被引:2,自引:0,他引:2
A. K. Dhar M. A. Pokras D. K. Garcia D. C. Evers Z. J. Gordon & A. Alcivar-Warren 《Molecular ecology》1997,6(6):581-586
We used random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphisms (RFLP) of mitochondrial cytochrome b (cyt b ) gene to evaluate the genetic diversity in common loon Gavia immer populations from two regions in the United States: New England (NE) and Michigan (MI). RAPD analysis with 18 primers showed 74% polymorphism in NE and 50% in MI loons (similarity coefficient F = 0.92). Although no population-specific markers were found, the frequencies of some RAPD bands varied between the two populations suggesting geographical differences. RFLP analyses with Bam HI enzyme and a 307-bp mitochondrial cyt b gene showed four haplotypes in the NE loon samples and two in the MI samples. The mtDNA haplotype diversity was 0.74 for NE and 0.51 for MI loons, supporting the RAPD data that NE loons have greater genetic diversity than MI loons. 相似文献
18.
K N Subramanian R Dhar S M Weissman P K Ghosh 《The Journal of biological chemistry》1977,252(1):340-354
19.
Limited T1 RNase digestion of subfragments of the SV40 DNA restriction endonuclease fragment EcoRII-G were prepared and analyzed. The fragments were separately labeled with 32P at their 5' terminus and the terminal sequences analyzed with limited snake venom diesterase digestion. The data permitted us to deduce the nucleotide sequence for EcoRII-G. The sequence contains a stretch of 17 A-T base pairs preceding the DNA complementary to the 5' end of "early" message RNA, a stretch of 27 bases with a perfect 2-fold rotational symmetry near the origin of DNA replication and a perfect tandem repeat of 21 nucleotides. 相似文献
20.
Ethanolic extract of the leaves of Vitex negundo yielded a new iridoid named 2′-p-hydroxybenzoyl mussaenosidic acid. The structure was established on the basis of chemical and spectral data. 相似文献