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11.
Seeds of two cultivars, H-14 and J-34 of Gossypium hirsutumL. soaked in the dark for durations of 8, 12 and 16 hr wereexposed to red and far-red radiations alone and in differentsuccessions. While cv. J-34 was unresponsive to all light treatments,seed germinaiton in cv.H-14 was promoted by darkness and byexposure to far-red radiation and was inhibited by red andwhitelight.Seed germination depended upon what treatment was given at theend. The effect ofred light was reversed by far-red and viceversa. Although instances of light inhibition of seed germinationare known, the authors are not aware of any clear cut instancein the literature on far-red promotion of seed germination (Received November 4, 1970; ) 相似文献
12.
Toshio Ariga Shama Bhat Takashi Kanda Masanaga Yamawaki Tadashi Tai Yasunori Kushi Takeshi Kasama Shizuo Handa Robert K. Yu 《Glycoconjugate journal》1996,13(2):135-145
We analysed the glycolipid composition of glioma cells (N-370 FG cells), which are derived from a culture of transformed human fetal glial cells. The neutral and acidic glycolipid fractions were isolated by column chromatography on DEAE-Sephadex and analysed by high-performance thin-layer chromatography (HPTLC). The neutral glycolipid fraction contained 1.6 µg of lipid-bound glucose/galactose per mg protein and consisted of GlcCer (11.4% of total neutral glycolipids), GalCer (21.5%), LacCer (21.4%), Gb4 (21.1%), and three unknown neutral glycolipids (23%). These unknown glycolipids were characterized as Lewisx (fucosylneolactonorpentaosyl ceramide; Lex), difucosylneolactonorhexaosyl ceramide (dimeric Lex), and neolactonorhexaosyl ceramide (nLc6) by an HPTLC-overlay method for glycolipids using specific mouse anti-glycolipid antibodies against glycolipid and/or liquid-secondary ion (LSI) mass spectrometry. The ganglioside fraction contained 0.6 µg of lipid-bound sialic acid per mg protein with GD1a as the predominant ganglioside species (83% of the total gangliosides) and GM3, GM2, and GM1 as minor components. Trace amounts of sialyl-Lex and the complex type of sialyl-Lex derivatives were also present. Immunocytochemical studies revealed that GD1a and GalCer were primarily localized on the surface of cell bodies. Interestingly, Lex glycolipids and sialyl-Lex were localized not only on the cell bodies but also on short cell processes. Especially, sialyl-Lex glycolipid was located on the tip of fine cellular processes. The unique localization of the Lex glycolipids suggests that they may be involved in cellular differentiation and initiation of cellular growth in this cell line. 相似文献
13.
Cells of Pseudomonas stutzeri in suspensions of TiO2 ranging in concentration from 0.5 to 4.0 g l-1 were irradiated with a blacklight blue u.v. source displaying peak emissivity at approximately 370 mm. Irradiation under these conditions is known to result in the generation of lethal free radicals. During irradiation the suspensions were agitated, using a specially modified laboratory shaker, to ensure efficient exposure of the TiO2 . A u.v. radiation dose of 175 kJ m-2 resulted in cell fractional survival ranging from 5.5 times 10-5 , at the lowest TiO2 concentration, to 1.0 times 10-6 , at the highest TiO2 concentration. The advantages of contactors employing TiO2 suspensions are briefly compared to immobilized TiO2 systems. 相似文献
14.
Path-coefficient analyses and genetic parameters of the components of field resistance of potatoes to late blight 总被引:4,自引:0,他引:4
Variation, genetic parameters, interrelationships and phenotypic and genetic path analyses for components of field resistance of potatoes to Phytophthora infestuns were studied using detached leaves from 16 potato cultivars. Inter-genotypic variability was significant for the components and the Area Under Disease Progress Curve (AUDPC). The resistant cultivars generally had a longer latent period and lower lesion size and spore production than the susceptible cultivars. The correlations between AUDPC and infection efficiency, and between AUDPC and spore density were not significant, but latent period, lesion size and sporulation did correlate significantly with AUDPC. Genetic and phenotypic path-coefficient analyses indicated lesion size to be the most important component of field resistance. The genetic correlation coefficients between the AUDPC and infection efficiency, latent period and spore density arose mainly because of their indirect effects on AUDPC via lesion size. Lesion size and AUDPC had a high genetic coefficient of variation, heritability and genetic advance (genetic gain). 相似文献
15.
Three formulations of the systemic fungicide metalaxyl were tested in various seed treatments for the control of pearl millet downy mildew in three field experiments with downy mildew-susceptible pearl millet hybrid NHB-3. Uniform, high levels of sporangial inoculum of the causal fungus, Sclerospora graminicola, were provided throughout the growth of the test crops from inoculated infector rows of NHB-3, planted earlier between the test plots. Significant reductions in downy mildew were obtained with all fungicide treatments. Best control was obtained when seed was soaked in a 0.5% aqueous solution of a liquid formulation (mean infection index of 9.8% compared with 94.8% in the untreated check). The degree of control with the wettable powder formulations was directly related to fungicide dosage, and there were no significant effects of application method. Simple dusting of seed at 2 g a.i./kg, a rapid and simple operation requiring small quantities of fungicide and no special application equipment, gave a high level of control (infection index of 12.6% compared with 78.9% in the untreated check). In two experiments grain yields from all the treated plots were significantly greater than from the untreated plots (means of 1234 and 1534 kg/ha for treated plots compared with 485 and 743 kg/ha, respectively), and in the third, the treatment with the least downy mildew gave significantly more grain than the untreated check (1228 compared with 727 kg/ha). 相似文献
16.
V. SINGH F.L.S. D. K. JAIN 《Botanical journal of the Linnean Society. Linnean Society of London》1975,70(3):243-253
The sequence of primordial initiation is acropetal and the primordia develop in the same order in which they appear. The floral apex has a two-layered tunica in all stages of development. There is no significant difference in the initiation of any of the floral appendages and thus all floral organs are homologous with respect to their histogenetic origin. The short calyx tube is formed by ontogenetic fusion of the bases of sepals; but the corolla tube arises partly by ontogenetic union of originally free parts and partly by zonal or intercalary growth. Each primordium receives a single procambium strand shortly after its initiation, except those of the posterior pair of stamens, which do not receive any vascular supply. This provides another example which goes against the doctrine of "conservatism of vascular bundles". The placentation in Justicia is parietal ontogenetically as well as anatomically. 相似文献
17.
An apparatus for automatic recording of losses of water frompotted plants, soil, &c., has been described. It is simple,and sufficiently robust for use in the open. Results on thedaily march of transpiration of wheat in the northern plainsof India have been given to demonstrate the working of the apparatus. 相似文献
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Using antibodies to rat neural cell adhesion molecules (NCAM), we analyzed the NCAM of adult human brain. Various regions of the brain were analyzed quantitatively by Western blot. Grey matter showed four bands of NCAM with apparent molecular weights of 180,000, 170,000, 140,000 and 120,000. White matter showed one major band with an apparent Mr of 120,000 and a minor band of 180,000. Cerebellar grey matter contained mainly 170,000, 140,000 and 120,000, white cerebellar white matter had only 180,000 and 120,000 M1 NCAMS. Spinal cord showed mainly 120,000 Mr NCAM. Deglycosylation using N-glycanase resulted in 170,000, 160,000, 130,000 and 110,000 Mr proteins, suggesting that the four forms of human NCAM are derived from individual polypeptides. The presence of 170,000 M1 NCAM is unique to human brain. 相似文献