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131.
MANUEL B. CRESPO ANTONIO DE LA TORRE JOSE L. SOLANAS 《Botanical journal of the Linnean Society. Linnean Society of London》1994,116(2):135-144
Linaria arabiniana sp. nov. is described from coastal sand dunes of a very reduced area in Alicante Province (south-eastern part of the Iberian Peninsula). It is a perennial herb characterized by its 3–4-verticillate leaves, glabrous stems, large violet or rarely yellow flowers, and bicoloured usually flat seeds. Morphological characteristics and taxonomic affinities of this taxon are discussed, as are data on its ecology, phytosociology, and eventual conservation features. 相似文献
132.
Lactobacillus lactis cells were infected with the bacteriophage ØLL55. The changes in DNA, RNA and protein synthesis were studied by following a long-term (over 3 h) incorporation of radioactive precursors into acid-insoluble material. Stimulation of DNA synthesis caused by phage occurred 30–35 min after infection and thymidine incorporation continued for about 70 min ceasing 10–20 min before the cells started to lyse. Cumulative (14C)-uracil incorporation into RNA continued at the level of uninfected cells for 30–40 min before starting to slow up. Protein synthesis in the infected cells followed that of a control culture for 40–50 min before the further incorporation of (14C)-leucine began to decrease.The additions of antibiotic inhibitors of RNA and protein synthesis (rifampicin and chloramphenicol, respectively) at various times before or during the prereplicative period showed that rifampicin, added up to 15 min after infection and chloramphenicol, added as late as 20–25 min after infection completely prevented the initiation of phage-genome replication. The later addition of these drugs did not prevent the out-burst of thymidine up-take, but promoted, however, a deduction in the initiations of new replication cycles. The results indicate that certain genes of ØLL55 genome must be expressed at the early stages of infection to confirm a proper onset and continuation of phage DNA replication.Abbreviations Rif
rifampicin
- CAL
chloramphenicol
- TCA
trichloroacetic acid
- cpm
counts per minute 相似文献
133.
Bulbs were obtained on onion plants cultured in vitro. No bulbinghappened under long days with fluorescent light and 3040g l1 sucrose. Bulb formation was mainly dependent eitheron sucrose concentration in the culture medium, or on lightspectral composition. Raising the sucrose concentration from40 to 120 g l1 increased plant basal swelling and stoppedfurther vegetative development. These plants were not dormant.When fluorescent light was enriched in incandescence duringa long day period, bulbs were obtained in two months and underwenta consecutive dormancy. Bulb, dormancy, light spectral quality, photoperiod, R: FR ratio, sugar, tissue culture 相似文献
134.
The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids. 相似文献
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LA BARRE J 《Journal de physiologie》1956,48(3):588-590
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