| In ion beam-mediated total DNA transformation, the total DNA consisted of all of genetic information in donor, and had multilateral effects on recipient, so there was no common rate of transformation to measure its effect, which meant that it was very difficult to decide an optimum condition of transformation such as influence. Implantation experiments showed that the relation between the influence and survival of A. Thailand was a saddle curve. Mint total DNA was transferred into A. Thaliana mediated by ion beam with the influence of 0.5 ×10 1.5 ×1017 and 2.5 ×1017 ions/cm2, respectively, which were on the bridge of saddle. Among three transferred populations, their budding, seedling, growth and phenotypic variation took on obvious difference. Combining these facts, the influence of 1.5 × 1017ions/cm2 was decided as transformation influence of the following work.The volatile oil of A. Thaliana transferred with mint total DNA was analyzed by means of GC-MS. Two transgenic plants were measured to contain menthol component in 250 plants of Tl generation and one plant in then* 267 progenies, which provided explicit evidence for ion beam-mediated polygenic character transmission between distant species. Two conclusions were drawn: one was that multiple genes controlling the same trait could be transformed into the receipt and efficiently expressed, the other was that the transferred new character was hereditary, i.e., the genes controlling the new character could inherit. Based on this, a reasonable hypothesis was put forward that primary genetic law in ion beam-transformation was decided by random integration of multiple genes controlling the same trait on receipt chromosomes and the Mendel heredity of these genes with located chromosomes.A. Thalianas were respectively introduced by ion beam with a collection of donor DNA having a gradient genetic relation with A. Thaliana. In vegetative phase of Tl, the ratio of phenotypic variation showed no distinct difference among these transformed populations. In reproductive phase, however, the ratio of low-fertilityplants first increased then decreased as genetic relation between exogenous donors and A. Thaliana reduced. It was suggested that exogenous DNA fragments (mainly non-coding sequence) had new mutagenetic mechanism as well as insertional mutagenesis. In T1 and T2, a number of mutants were obtained. To some degree, the inheritance and segregation of variant traits had a link with genetic relation between exogenous DNA donor and receipt. Two variant lines, named by TC243-1 and TC243-2, had been obtained and their variant traits had been steadily inherited to T5. The query to NASC suggested that TC243-1 and TC243-2 were new mutants.The molecular analysis of transferred plants and their offspring was carried out from the following four aspects. First, the fact that the phenotypic variation in T1 mainly resulted from transformation of exogenous DNA rather than ion beam mutagenesis was verified by RAPD-PCR amplification to mutants, exogenous DNA-transferred plants and ion beam-implanted plants. Second, an absent band, marked by Sieg-isso, was found in the RAPD-PCT amplification to T-6 and its progenies, which meant that the corresponding mutation was hereditary. This mutation was located between exon 1791-2691 and exonl-395 of ABC-Transporter gene. Third, a new band, Sne-ezo, was obtained from RAPD-PCT amplification to T-5 and one progeny. Sequence alignment and Southern blot showed that this band was not the sequence of A. Thaliana genome, but from exogenous DNA donor cabbage genome. It could be served as direct molecular evidence that the exogenous DNA could be transferred into receipt mediated by ion beam. Further analysis showed that this exogenous DNA fragment had changed in structure during the transformation. Finally, the variant line TC243-2, was analyzed by RAPD-PCR amplification with 100 random primers. The results suggested that phenotypic variation came from exogenous DNA transformation rather than exogenous pollen contamination. A mutat...
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