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81.
B. N. Dahiya V. P. Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(5):678-681
Summary Three selection methods (single seed descent (SSD), mass selection and selective intermating) were applied simultaneously to a highly heterogeneous and broadly based population of greengram. Progeny developing after two cycles of selection were evaluated for yield and seven other economic characters. The relative efficacy of each selection method was judged on the basis of the number of high yielding progeny, mean yield of top 10% progeny, and mean of the highest yielding progeny. Selection after two cycles of selective intermating was found to be the best method for generating productive progeny although mass selection favouring smaller seeds was an equally efficient method. Both of these were found superior to SSD selection. 相似文献
82.
C. P. Malik Usha Parmar Parmil Singh K. L. Ahuja R. K. Raheja 《Plant Growth Regulation》1986,4(2):159-168
Plants of peanut (Arachis hypogaea L. var. PG No. 1) were given two foliar sprays of phenolic compounds (H-acid, 1, 2, 4-acid, resorcinol and RD-Brown) at 100 and 200 ppm, 35 and 50 days after sowing. In treated plants, shelling %, yield (kg/ha), number of gynophores per plant and number of pods per plant were significantly greater than in the control. Oil content of kernels also showed a significant increase with all the phenolic compounds applied. These compounds increased the linoleic acid concentration so improving nutritional quality. The number of gynophores was significantly correlated with the number of pods per plant and yield per hectare. The effect of phenolic compounds on growth and development was independent of their structural configuration. 相似文献
83.
Twenty-four LSH and LVG strain golden hamsters, Mesocricetus auratus, were used. Experimental animals were maintained at 5 C and allowed to hibernate. Control animals were kept at 27 C. Six animals (3 experimental, 3 control) were injected subcutaneously with 1 microCi of 3H-proline/gm body wt. (Spec. act. 3 Ci/mM) after hibernation lasting 12 hours, 1 day, 3 days, or 7 days. Animals were killed 1 hour after injection and autoradiographs were prepared from 5 microns thick decalcified sections of femurs. A greater number of endosteal cells were labeled than periosteal cells and also exhibited a greater magnitude of labeling throughout the study. Differences between endosteal and periosteal cells both in percentage of cells labeled and magnitude of labeling were maximum in control animals and progressively decreased with increasing periods of hibernation. A reduction in synthesis of matrix proteins during the early period of hibernation was seen and was attributed to a significant reduction both in average cell activity and in the number of active cells during hibernation. The latter phenomenon apparently made a large contribution to the reduced matrical synthesis. 3H-proline uptake by osteoblasts probably reflects the reduced requirements of matrical synthesis during hibernation. 相似文献
84.
Detection of a homologous series of C26-C38 polyenoic fatty acids in the brain of patients without peroxisomes (Zellweger''s syndrome). 总被引:2,自引:1,他引:1 下载免费PDF全文
A Poulos P Sharp H Singh D Johnson A Fellenberg A Pollard 《The Biochemical journal》1986,235(2):607-610
The brains of patients with inherited abnormalities in peroxisomal structure and function contain greatly increased proportions of a homologous series of unique polyenoic fatty acids with carbon chain lengths ranging from 26 to 38. Based on evidence by chemical ionization and electron impact mass spectrometry before and after catalytic hydrogenation, and argentation t.l.c., these lipids have been tentatively identified as 26:5, 28:5, 30:5, 30:6, 30:7, 32:5, 32:6, 32:7, 34:5 and 34:6 fatty acids. A further two fatty acids eluting at very high temperatures from gas chromatography columns have been tentatively identified on the basis of their chemical ionization mass spectra as 36:6 and 38:6 fatty acids. 相似文献
85.
The structural gene for the mitochondrial aldehyde dehydrogenase maps to human chromosome 12 总被引:1,自引:1,他引:0
T. Braun K. H. Grzeschik E. Bober S. Singh D. P. Agarwal H. W. Goedde 《Human genetics》1986,73(4):365-367
Summary A cloned 850 bp cDNA fragment corresponding to the 3-coding part of human ALDHI-mRNA was used as a probe for the chromosomal assignment of the ALDHI gene. Southern blot analysis of human-rodent somatic cell hybrids indicates that the human ALDHI gene resides on chromosome 12.Dedicated to Prof. Dr. H. Holzer on the occasion of his 65. birthday 相似文献
86.
Summary Probes of uncloned Bkm satellite DNA and a Drosophila clone 2(8), consisting mainly of GATA repeasts related to a major sequence component in Bkm, have been used to probe Southern blots of human male and female DNAs obtained from a Caucasian and an Australian aboriginal population and to human chromosomes in situ. Hybridization was observed to a distinct and an indistint series of bands against a smeared background. The same distinct bands are identified in the DNA samples with both probes, but are most readily detected using the uncloned Bkm probe. Most restriction bands are common to both populations and some are polymorphic. However, certain bands appear to be characteristic of the Australian aboriginal samples. There are no distinct sex-linked patterns. However all of the small acrocentric human chromosomes, including the Y chromosome show hybridization to uncloned Bkm in situ. 相似文献
87.
Using two species of yeast and one of bacterium, evidence has ben obtained which indicates that the microbial uptake of solid alkane powders occurs primarily through a substrate solubilization mechanism. EDTA, a strong inhibitor of hydrocarbon solubilization by the cells, inhibited the growth of these organisms on alkane powder; the inhibition could be removed vai a supply of artificially solubilized alkane. One of the yeast strians, which was a mutant incapable of growing on solid alkane powder and liquid alkane, could grow very well on artifically solubilized alkanes. It was demonstrated that the solid alkane solubilization rate during microbial growth could satisfactorily account for the maximal alkane uptake rate actully observed during growth. The specificity of solubilization for the solid alkane used as the growth substrate was demonstrated. 相似文献
88.
Injection of folic acid (FA) into the nucleus substantia innominata (NSI) was found to decrease [3H]quinuclidinyl benzilate ([3H]QNB) binding in the frontal cortex, pyriform cortex, amygdala, and the NSI itself without changing the KD. Binding in the thalamus, caudate nucleus, hippocampus, and substantia nigra was not affected. [3H]Flunitrazepam binding was unchanged in all eight regions studied. Previous work indicates FA injections into the NSI produce epileptiform activity and cause loss of GABAergic and possibly other neurons in the frontal and pyriform cortices, the amygdala, and thalamus. The reductions of [3H]QNB binding in the first three of these regions are interpreted as indicating that many of the neurons lost are cholinoceptive, a finding that supports the previous hypothesis that activation of cholinergic projections from the NSI is an important part of the mechanism of cell loss in these regions. 相似文献
89.
R. S. Singh S. K. Jain 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1971,41(2):79-84
Summary Surveys for polymorphisms in natural populations of A. barbata sampled in California grasslands had provided evidence for widespread monomorphism and rather localized polymorphic areas in the north coastal and San Francisco regions, based on a set of morphological and isoenzymatic marker loci. Since this species, like many other annuals, was introduced from the Mediterranean region during the Spanish mission period, a comparative study of the Canadian-Welsh collections of Avena species from the Mediterranean region was undertaken using various plant characters and starch gel electrophoresis to analyze variants for esterase, phosphatase and peroxidase systems. A total of 96 samples including 73 of A. barbata and 23 of A. hirtula were studied and the results were scored to compute the polymorphism indices. In both species, only 10 to 15 percent sites showed any significant degree of polymorphism of which a majority seemed to originate from localized regions in Italy and Turkey; a part of this observed lack of within-sample variation might be the result of small sample size. In general, the patterns of variation in A. barbata from the California surveys and the present analyses seemed to be very similar and raised some interesting questions on (a) the colonizing history of introduced materials (b) the factors underlying such marked patterns of geographical variation, and (c) the current evolutionary changes occurring in these two broad, disjunct areas of species distribution.
This work was supported in part by a grant from the National Science Foundation (GB 8627). 相似文献
Zusammenfassung Untersuchungen der Polymorphismen in natürlichen Populationen von A. barbata im kalifornischen Weideland hatten einerseits zum Nachweis eines weit verbreiteten Monomorphismus und andererseits streng lokalisierter polymorpher Bereiche in der nördlichen Küsten- und San Francisco-Region geführt, wobei eine Anzahl morphologischer und isoenzymatischer Markerloci zugrunde gelegt wurde. Da diese Art, wie viele andere Annuelle auch, während der spanischen Missionsperiode aus der Mittelmeerregion eingeführt wurde, wurde eine vergleichende Untersuchung der Canadian-Welsh-Sammlungen von Avena-Arten aus der Mittelmeerregion anhand verschiedener Merkmale der Pflanzen und der Stärkegelelektrophorese-Untersuchung auf Esterase-, Phosphatase- und Peroxydase-Systeme durchgeführt. Es wurde eine Gesamtheit von 96 Stichproben, bestehend aus 73 A. barbata und 23 A. hirtula, untersucht und die Ergebnisse zur Berechnung von Polymorphismus-Indices verwendet. In beiden Arten zeigten nur 10 bis 15% der Herkünfte einen signifikanten Polymorphismusgrad. Von ihnen scheint die Mehrzahl von lokalisierten Regionen in Italien und Griechenland abzustammen. Ein Teil des beobachteten Fehlens einer Variation innerhalb der Stichproben könnte eine Folge des geringen Stichprobenumfangs sein. Im allgemeinen scheinen die Variationsmuster der kalifornischen Untersuchungen und die der vorliegenden Analysen von A. barbata sehr ähnlich zu sein. Das führt zu einigen interessanten Fragen nach a) der Besiedelungsgeschichte des eingeführten Materials, b) den Faktoren, die derart auffallenden Mustern der geographischen Variation unterliegen und c) den laufenden evolutionären Änderungen, die in diesen beiden großen, voneinander getrennten Gebieten der Artverteilung auftreten.
This work was supported in part by a grant from the National Science Foundation (GB 8627). 相似文献
90.
R. B. Singh Ben W. Smith 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1971,41(8):360-364
Summary Cytogenetic studies were made with particular emphasis on the sex-determining mechanism in Rumex acetosella (6 x = 42) and its hybrids (F
1, F
2, BC
1 and BC
2) with R. hastatulus (synthetic 4 x = 16 = 4 A +4 X = and 4 x = 18 = 4 A + 2 (X Y
1
Y
2) = ). Rumex acetosella was almost strictly dioecious with 5050 male and female. Breeding tests revealed that the males were heterogametic. The longest chromosomes (S), usually two, are the sex chromosomes of this hexaploid species. The S chromosomes are homomorphic in both male and female. The sex chromosome: autosome ratios, and the strong epistatic male effect of the S
M chromosome in the polyploid dioecious species and in the hybrids, are evidence of an X/Y Melandrium type sex-determining mechanism controlled by a single pair of homomorphic sex chromosomes. Thus, the sex chromosome formula of the males was S
F
S
M and that of females was S
F
S
F. The present approach is a new method for resolving the sex-determining mechanism in a dioecious species. 相似文献