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Hi Dale, Regarding the most significant point double fertilization you seem to be misunderstanding or just obfuscating the main point. In single fertilizations or plants with little or no endosperm the transgenic portion of the seed is limited to an immature embryo making up a minute portion of the seed. The GM plant with every cell containing transgenes will not appear until the following season of growth of the seed. In grain of the endosperm rich crops a large portion of the seed is triploid endosperm containing transgenic cells. So in the crops lacking endosperm the GM content of the crop is heavily laden with transgenic material in the generation of the fertilization. If you do not understand that simple point it is not surprising that agricultural bureaucrats often too ignore plant biology. The point you made about GM detection in kernels is strange to say the least. The difference between a seed with no endosperm and a minute embryo and a seed rich in endosperm may be as much as 100,000 to a million times in number of transgenes in each kernel. The food standards for GM content are not set for number of transgenic kernels but for transgene content in the food! Again it is very unwise to pretend that transgenic endosperm does not count in grain crops! Most transgenes are dominant in _expression_ but homozygous GM crops are not uncommon as are hemizygous crops, a point that is not relevant to the discussion of endosperm. Keeping focused on endosperm , that tissue contains one transgene , say, for every two normal genes but that ratio is offset by the huge production of endosperm relative to embryo. Of course, endosperm does not pass its genes to the next generation but it makes a huge impact on grain crops in the generation of fertilization. The amplification of transgenes under selection is a separate story. Thanks for your comments, dale, they are as always very amusing. Sincerely, Joe Dale Wilson wrote: Joe,I think that we should make it clear that the plants double fertilization has an important impact. In plants the pollen fertilizes both the egg cell and the endosperm nucleus to produce a triploid. So unlike the embryo whose _expression_ is delayed to the next planting the endosperm expresses the transgene in the the immediate generation fertilized by 5 plants in each 1000 plants produced.
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