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61.
Patterns of nucleic acids synthesis in normal and crown gall tumor tissue cultures of tobacco 总被引:3,自引:0,他引:3
B I Srivastava 《Archives of biochemistry and biophysics》1968,125(3):817-823
62.
63.
64.
Proteolytic enzymes in normal and dystrophic mouse muscle 总被引:2,自引:0,他引:2
65.
66.
67.
B I Srivastava 《Biochimica et biophysica acta》1965,103(2):349-352
68.
Ribonucleic acids from barley leaves 总被引:1,自引:1,他引:0
B. I. Sahai Srivastava 《The Biochemical journal》1965,96(3):665-670
1. The total RNA and the RNA present in 27000g pellet (probably composed of chloroplasts, nuclei and mitochondria) and in 27000g supernatant (probably composed of microsomes and soluble proteins) fractions (separated by centrifugation at 27000g of a leaf homogenate prepared in 0·5m-sucrose–0·02m-tris–HCl, pH7·6) of barley leaves were extracted by phenol–sodium lauryl sulphate and their elution profiles on Sephadex G-200 and on ECTEOLA-cellulose anion-exchanger were examined and their nucleotide compositions and the melting curves were determined. 2. The pellet and the supernatant fractions contained respectively about 55% and 20% of the total RNA, whereas 25% of the total RNA was lost during homogenization of the leaf tissue with sucrose–buffer. 3. The total RNA or the RNA from pellet or supernatant fractions, which by its behaviour on Sephadex G-200 columns was found to be predominantly of high molecular weight (i.e. of ribosomal origin), produced about 13 peaks on ECTEOLA-cellulose columns. The RNA species in the pellet and supernatant fractions probably resembled each other in molecular size or secondary structure or both. However, they were present in relatively different amounts in these fractions. 4. The Tm (i.e. the temperature at which 50% of the maximal increase in extinction had occurred) of total RNA and of RNA from pellet fraction was 64·5° whereas Tm of RNA from the supernatant fraction was 73°. The total RNA and the RNA from pellet fraction also resembled each other in nucleotide composition, and the RNA from the supernatant fraction in accordance with its high Tm had a high GMP+CMP content. 相似文献
69.
The influence of kairomones on the numerical response of the parasitoidTrioxys indicus against its hostAphis craccivora at its varying density was studied. The kairomones (applied as aqueous extract of the host) significantly enhanced the rate
of parasitisation and multiplication and the area of discovery of the parasitoid and also the K-values of mortality of the
host at all parasitoid densities introduced (1, 2, 4, 8, 12 and 16 parasitoids) into troughs having about 200 hosts. The sex-ratio
of F1 offspring decreased at lower parasitoid densities and remained more or less unchanged at higher parasitoid densities after
the application of kairomones. The present findings indicate that if kairomones are applied properly, the number of hosts
destroyed by a stimulated parasitoid will be about 200, twice the number reported earlier, thus fewer parasitoids will be
needed to regulate an estimated population of the hosts.
相似文献
70.
Plants were regenerated from cotyledon and hypocotyl explants of watermelon (Citrullus vulgaris). The explants were cultured on a Murashige and Skoog's basal nutrient medium supplemented with auxin, cytokinin and auxin-cytokinin combinations. Green healthy nodular and compact callus was obtained in medium containing naphthalene acetic acid and benzylaminopurine. Shoot differentiation and root differentiation from the cotyledon and hypocotyl after callus formation in different media containing benzylaminopurine or naphthalene acetic acid, respectively. Shoot formation required benzylaminopurine. Kinetin proved ineffective in inducing shoot buds or shoots. Root differentiation occurred in a medium containing naphthalene acetic acid or indole acetic acid. There was a greater proliferation of roots on medium supplemented with naphthalene acetic acid. The regenerated shoots developed roots when transferred to medium containing naphthalene acetic acid and complete plantlets could be transferred to soil for further growth.Abbreviations BAP
6 Benzylaminopurine
- NAA
-Naphthalene acetic acid
- MS
Murashige and Skoog's medium
- IAA
Indole acetic acid
- KN
Kinetin 相似文献