Effects of mercaptoethanol on tumor induction in a Nicotiana amphiploid

1969 ◽  
Vol 47 (6) ◽  
pp. 921-924 ◽  
Author(s):  
I. H. Ames ◽  
H. H. Smith
Keyword(s):  
Nutrient Medium ◽  
Tumor Formation ◽  
Test Solution ◽  
Nicotiana Glauca ◽  
Tumor Induction ◽  
Alkaline Range

Young seedlings of the amphiploid Nicotiana glauca × N. langsdorffii, grown aseptically on nutrient medium, were treated with solutions containing 2-mercaptoethanol, and the incidence of tumor formation was scored for 30 days subsequent to exposure. Mercaptoethanol caused a marked acceleration in the rate of tumorigenesis when the pH of the test solution was in the alkaline range. The effectiveness of the compound was reduced by lowering the pH of the treatment solution.

Gibberellic acid: effect on genetic tumor induction

1971 ◽  
Vol 49 (9) ◽  
pp. 1699-1701 ◽  
Author(s):  
Ira H. Ames
Keyword(s):  
Gibberellic Acid ◽  
Nutrient Medium ◽  
Stem Growth ◽  
Tumor Formation ◽  
Trigger Mechanism ◽  
Tumor Induction ◽  
Acid Effect ◽  
Nicotiana Suaveolens ◽  
Marked Enhancement

Young seedlings of the amphiploid Nicotiana suaveolens × N. langsdorffii, grown aseptically on nutrient medium, were treated with several concentrations of gibberellic acid (GA3). The incidence of tumor formation was scored for 18 days subsequent to exposure. At a concentration of 5 × 10−3 M, GA3 caused a striking reduction in the rate of tumor formation and a marked enhancement of stem growth in this tumor-prone amphiploid. These results are discussed in relation to the problem of the trigger mechanism for tumor induction in Nicotiana hybrids.

The influence of cytokinins on genetic tumor formation

1972 ◽  
Vol 50 (11) ◽  
pp. 2235-2238 ◽  
Author(s):  
Ira H. Ames
Keyword(s):  
Nutrient Medium ◽  
Tumor Formation ◽  
Trigger Mechanism ◽  
Tumor Induction ◽  
Nicotiana Species ◽  
Species Hybrids

Young seedlings of two tumor-prone Nicotiana amphiploids, grown aseptically on nutrient medium, were treated with either N6-benzyladenine or kinetin. The incidence of tumor formation was scored for 18 days subsequent to exposure. These cytokinins markedly accelerated the rate of tumorigenesis in both amphiploids. The results are discussed in relation to the problem of the trigger mechanism for tumor induction in Nicotiana species hybrids.

Induction of tumor formation in Nicotiana amphiploids with triiodobenzoic acid

1970 ◽  
Vol 48 (12) ◽  
pp. 2209-2212 ◽  
Author(s):  
Ira H. Ames
Keyword(s):  
Nutrient Medium ◽  
Parental Species ◽  
Tumor Formation ◽  
Trigger Mechanism ◽  
Tumor Induction ◽  
Nicotiana Species ◽  
Triiodobenzoic Acid ◽  
Species Hybrids

Young seedlings of two tumorous Nicotiana amphiploids and the parental species, grown aseptically on nutrient medium, were treated with 2,3,5-triiodobenzoic acid. The incidence of tumor formation was scored for 18 days subsequent to exposure. Triiodobenzoic acid markedly accelerated the rate of tumorigenesis in both amphiploids, but it did not induce tumors in the parental species. The compound also induced tumor formation in a small percentage of seedlings of a non-tumorous mutant of the N. glauca × N. langsdorffii amphiploid. These results are discussed in relation to the problem of the trigger mechanism for tumor induction in Nicotiana species hybrids.<

scholarly journals The Presence and Characterization of a virF Gene on Agrobacterium vitis Ti Plasmids

1998 ◽  
Vol 11 (5) ◽  
pp. 429-433 ◽  
Author(s):  
B. Schrammeijer ◽  
J. Hemelaar ◽  
P. J. J. Hooykaas
Keyword(s):  
Amino Acids ◽  
Agrobacterium Tumefaciens ◽  
Molecular Mass ◽  
Promoter Region ◽  
Consensus Sequence ◽  
Tumor Formation ◽  
Nicotiana Glauca ◽  
Agrobacterium Vitis ◽  
Ti Plasmids

Octopine and nopaline strains of Agrobacterium tumefaciens differ in their ability to induce tumors on Nicotiana glauca. The presence of a virF locus on the octopine Ti plasmid makes N. glauca a host plant for these strains, indicating that the VirF protein is a host-range determinant. Here we show the presence of a virF locus not only on the Agrobacterium vitis octopine/cucumopine plasmids pTiAg57 and pTiTm4, but also on the nopaline Ti plas-mids pTiAT1, pTiAT66a, and pTiAT66b. On the octopine Ti plasmids from A. tumefaciens the virF gene is located between the virE locus and the left border of the T-region. In contrast, the virF gene on Ti plasmids of A. vitis is located at the very left end of the vir-region near the virA locus. The virF gene of pTiAg57 has been sequenced and codes for a protein of 202 amino acids with a molecular mass of 22,280 Da. Comparison showed that the virF gene from A. vitis strain Ag57 is almost identical to that from A. tumefaciens octopine strains. The transcription of the pTiAg57 virF is inducible by the plant phenolic compound acetosyringone through the presence of a vir-box consensus sequence in its promoter region. The VirF protein from pTiAg57 can complement octopine A. tumefaciens strains deleted for virF as shown by tumor formation on N. glauca.

Untersuchungen an Crown-Gall

1970 ◽  
Vol 25 (7) ◽  
pp. 735-738 ◽  
Author(s):  
Rolf Beiderbeck
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Crown Gall ◽  
Tumor Formation ◽  
Tumor Induction ◽  
Host System ◽  
Induced Tumors ◽  
Kalanchoë Daigremontiana ◽  
Kalanchoe Daigremontiana

Concentrations of 10 µg/ml rifampicin reduce the growth of Agrobacterium tumefaciens by more than 90%, concentrations of 100 µg/ml prevent tumor formation in Kalanchoë daigremontiana by the same bacteria.A treatment with rifampicin does not irreversibly alter the bacteria; after removal of the drug bacterial propagation and the ability of tumor induction are restored.0-24 h treatments of the plant wounds with rifampicin prior to infection prevent tumor formation completely.Addition of rifampicin after infection inhibits tumor formation optimally if the drug is added only few hours after inoculation. 30 h after infection the bacteria-host-system is resistant against rifampicin.100 μg/ml rifampicin do not influence the growth of already induced tumors.

Kontakt von Agrobacterium mit Wundrandzellen als Vorbedingung für eine Tumorinduktion / Contact of Agrobacterium with Wound Cells as a Prerequisite of Tumor Induction

1976 ◽  
Vol 31 (5-6) ◽  
pp. 317-318 ◽  
Author(s):  
Rolf Beiderbeck
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Tumor Formation ◽  
Mass Relation ◽  
Tumor Induction ◽  
Infected Wounds

Tumor induction by Agrobacterium tumefaciens on Kalanchoe leaves is suppressed by charcoal mixed with the inoculum. The inhibition works best with a certain mass relation between bacteria and charcoal. The bacteria become adsorbed to the charcoal particles and in this state they are unable to induce tumors. If charcoal is added to bacteria-infected wounds only 15 min after infection it is not interfering with tumor formation. These results are supporting the hypothesis of sites in the wound to which Agrobacterium has to be attached to incite tumors.

TUMOR INDUCTION IN VICIA FABA AND OTHER HOSTS BY AGROBACTERIUM RUBI (HILDEBRAND) STARR AND WEISS

1950 ◽  
Vol 28c (3) ◽  
pp. 277-282 ◽  
Author(s):  
L. C. Coleman
Keyword(s):  
Host Range ◽  
Vicia Faba ◽  
Cytological Study ◽  
Tumor Formation ◽  
Host Responses ◽  
Tumor Induction ◽  
Suitable Material ◽  
Rubus Species ◽  
Important Addition ◽  
Plant Tumors

In a search for suitable material for a cytological study of plant tumors, pure and virulent cultures of Agrobacterium tumefaciens were inoculated into stems of young Vicia faba plants without result. On the other hand, a bacterium isolated from Himalaya blackberry produced large tumors. A comparison of the two forms as to their virulence on other plant species showed that the blackberry organism would not attack tomato, Nicctiana glutinosa, and Datura medeloides, all highly susceptible to A. tumefaciens. Sunflower proved to be a common host to the two pathogens, but the host responses showed significant differences. The tumors caused by the blackberry organism were smaller and were not accompanied by epinasty of the leaves immediately above the tumor, a characteristic feature associated with tumor formation induced by A. tumefaciens. From cultural characters and differences in host range, it was decided that the blackberry organism belongs to Agrobacterium rubi (Hildebrand) Starr & Weiss., a species considered as confined to Rubus species. Its host range is obviously much wider than this and, as it embraces plants only slightly or not at all susceptible to A. tumefaciens, it is likely to prove an important addition to this species in providing material for the study of plant tumors.

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