Page:Popular Science Monthly Volume 77.djvu/351

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PLANT BREEDING
345

Fig. 1. Castration of Buds of Nicotiana tabacum before Crossing, a, correct stage for castration; b, method of slitting the corolla; c, castrated bud.

The theory supposes that when a dominant and a recessive character meet in a cross, the germ cells which are produced in the hybrid do not blend these characters, but possess either the one or the other; and as the possession of either character is a matter of chance, on the average 50 per cent, will bear the dominant and 50 per cent, will bear the recessive character. In a plant, for example, 50 per cent, of the pollen cells would bear the dominant and the other 50 per cent, would

Fig. 2. Castrated Bud of Impatiens sultani showing Method of Protection in Greenhouse Work.