| Research Abstract |
This study was carried out in 1996 to 1998, using the stamen-hair system of Tradescantia clone BNL 4430, in order to investigate (1) the mutagenicities of alkylating agents and their mutagenic synergisms with X rays, (2) the mutagenic synergisms among alkylating agents, (3) the mutagenicities of promutagens and their mutagenic interactions with X rays, and (4) the mutagenic interactions between promutagens and alkylating agents.
(1) The mutagenicities of N-ethyl-N-nitrosourea (ENU), diethyl sulfate (DES) and 1 , 2-dibromoethane (EDB) were determined, adding to those determined earlier for ethyl methanesulfonate (EMS), methyl methanesulfonate (MMS), dimethyl sulfate (DMS) and N-methyl-N-nitrosourea (MNU). ENU, DES and EDB all acted synergistically with X rays, as EMS, MMS and DMS did. (2) MNU acted merely additively with EMS, differing from MMS and EMS which acted synergistically. (3) The mutagenicities of o-phenylenediamine (PDA), N-nitrosodimethylamine (DMN) and EDB (also a bitunctional alkylating agent) were determined, and PDA and DMN were found to act synergistically with X rays when treated after exposing to X rays but antagonistically when treated before exposing to X rays, similarly to maleic hydrazide (MH) studed earlier. However, PDA and DMN acted synergistically and additively with X rays, respectively, when X-rayed during PDA and DMN treatments, indicating different time periods needed for their activations by peroxidase. (4) MH and EMS were found to act always antagonistically.
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