Breeding and the Mendelian discovery / by A.D. Darbishire ... with illustrations in colour and black-and-white.

  • Arthur Dukinfield Darbishire
Date:
1911
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Breeding and the Mendelian discovery / by A.D. Darbishire ... with illustrations in colour and black-and-white. Source: Wellcome Collection.

    165/370 page 103
    CHARACTERS OF DISTINCT PAIRS 103 [2. Yellow wrinkled]— Pure yellow and wrinkled. . 1x1 = 1 Hybrid yellow and wrinkled . 2x1 = 2 —3 [3. Green round]— Green and pure round Green and hybrid round . 1x1 = 1 1X2 = 2 —3 [4. Green wrinkled]— Green and wrinkled . 1x1 = 1 —1 The epithet pure is omitted before the recessive character in the above table to lay stress on the fact that the recessive character is always pure. To consider for a moment the practical application of the facts which have now been set forth, it will be seen that there are four combinations of characters in this second hybrid generation, two of which are different from the parent forms started with, namely, the green wrinkled and the yellow round. Of these four combinations only one type—that which possesses two recessive characters, the green wrinkled—can be counted on to breed true, straight away. We have to wait no longer in this instance than the second hybrid generation for a constant new variety. In the case of the other three combinations, it is necessary to wait till the next generation before we can be certain of getting a constant type. For directly we find a plant (bearing a fairly large number of seeds)
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