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81.
Prolific shoot bud differentiation was induced in callus and suspension cultures of hypocotyl origin in Brassica campestris cv. Yellow Sarson on MS medium supplemented with K (13.9–23.2 M) or BA (13.3–22.1 M). Plantlets were obtained by rooting the in vitro differentiated shoots. Histological studies revealed a unique mode of meristemoid formation.Abbreviations MS
Murashige and Skoog (1962)
- 2,4-D
2,4-dichlorophenoxyacetic acid
- BA
Benzyladenine
- IAA
Indole-3-acetic acid
- IBA
Indolebutyric acid
- K
Kinetin
- NAA
Naphthalene acetic acid 相似文献
82.
83.
In nonamended soil, vegetative growth and sporulation ofFusarium spp. were higher in the rhizosphere than in the soil. Sporulation was favoured by young plants and decreased with increasing
plant age. Amendments with low C/N oil-cakes enhanced vegetative growth and sporulation in root-free soil. The extent of stimulation
varied with the nature of organic matter used and the stage of its deoomposition. Sporulation was suppressed by castor cake
and sawdust with urea amendments. Rhizosphere cf pea altered the effect of different amendments. 相似文献
84.
85.
86.
1. ATP-dependent proton translocation and ATP-dependent quenching of the fluorescence of 9-aminoacridine were measured in inside-out vesicles derived from a cytochrome-deficient mutant of Escherichia coli. 2. ATP-dependent quenching of fluorescence was inhibited by nigericin gramicidin, NH4Cl, and carbonylcyanide-m-chlorophenylhydrazone. Inhibition was also produced by the ATPase inhibitors N,N'-dicyclohexylcarbodimide (DCCD) and diphenyl phosphorazidate (DPA), and by the respiratory chain inhibitors piericidin A, 2-heptyl-4-hydroxyquinoline N-oxide, and An2+. The inhibition of ATP-dependent fluorescence quenching by the ionophores, uncouplers, and respiratory chain inhibitors was not due to an effect on ATPase activity which was insensitive to these agents. 3. By use of the ATPase inhibitors DCCD and DPA, or by replacing ATP with GTP, ITP and CTP, a correlation between the ATPase activity and the rate of ATP-dependent membrane energization, as measured by fluorescence quenching, was obtained. 相似文献
87.
Summary The concentration, uptake and element use efficiency of N, P and K in one C3 annual (Polypogon monspeliensis) and two C4 (Echinochloa colonum, an annual, andDichathium annulatum, a perennial) grasses were determined during winter and summer seasons in monocultures raised in field plots at three moisture
levels,viz. full, half and one-fourth of field capacity. At each moisture regime the plants were clipped thrice at moderate and severe
levels corresponding to 40 and 80% of live green. The concentration of these elements was characteristic of the growth habit
of these plants;e.g. the build up of concentration was maximum in leaf of the annuals while it was comparable in crown and leaf of Dichanthium.
The N level was maximum in Polypogon. The nutrient use effiency was comparable in the two annuals and maximum K and N use
were obtained in Polypogon and Dichanthium, respectively. 相似文献
88.
A determinate scheme for modeling the mechanical effects of muscle contractions in a musculoskeletal system, using the direct-stiffness method of structural analysis, is described. Data concerning skeletal geometries, connective tissue passive mechanical properties, and muscle lines-of-action and cross-sectional areas are incorporated to make the model specific for studies of muscle actions in the human trunk. Several illustrative examples of model trunk responses to muscle contractions are presented and discussed. 相似文献
89.
N J Oppenheimer M Singh C C Sweeley S J Sung P A Srere 《The Journal of biological chemistry》1979,254(4):1000-1002
The structure of the prosthetic group of citrate lyase (Klebsiella aerogenes) was studied by nuclear magnetic resonance and mass spectrometry. The spectra at 360 MHz of the nucleoside moiety (2'-ribosyladenosine) show the absence of 2'-hydroxyl proton, thus confirming the 2' position as the site of attachment of the second ribose moiety to the dephospho-CoA. This glycosidic linkage is found to be alpha(1" leads to 2') and is identical to that of poly(ADP-ribose). Studies of permethylation products by mass spectrometry support the above conclusion regarding the location of the ribosidic linkage. 相似文献
90.
I Singh Y Kishimoto R R Vunnam N S Radin 《The Journal of biological chemistry》1979,254(10):3840-3844
Three synthetic compounds which affect sphingolipid metabolism in vitro were examined for their effects on the synthesis in a rat brain system of nonhydroxyceramide, hydroxyceramide, nonhydroxycerebroside, and hydroxycerebroside from [1-14C]ignoceric acid. These compounds are N-octanoyl-D-threo-p-nitrophenylaminopropanediol (Compound I), N-(2,3-epoxydecanoyl)-norephedrine (Compound II), and N-decyl-N'-glucosylthiourea (Compound III). In the presence of up to 0.5 mM Compound I, only the hydroxyceramide fromation increased, while the synthesis of the other three lipids decreased. Compound II strongly inhibited the formation of all four lipids at all concentrations tested (0.1 to 1 mM). Compound III increased the synthesis of both ceramides approximately 2-fold at 1 mM, but the conversion of lignoceric acid to both cerebrosides remained relatively unchanged. Several significant conclusions from these observations are discussed. 相似文献