HORTICULTURAL SOCIETY OF NEW YORK. 



CAN SPORTING OF PLANTS BE INDUCED? 



BY L. C. CORBETT, MARCH 8, I9O4. 



The sporting of plants as we term the vegetative variations which occur 

 during the life of the individual is only a special form of variation. Variation 

 we know is the natural tendency of plants and animals. The direction and 

 extent of such variation is frequently predetermined by external circumstances — 

 environment — or by inherent tendencies of the individual or species. 



In fact, fixity of type, either in nature or under cultivation, is a very difficult 

 thing to attain, as all seedsmen and plantsmen well know. The fixity which 

 appears to exist in nature and which is responsible for the existence of so- 

 called species is the result of certain limiting forces working in conjunction 

 through countless generations. Break up this deadlock and the species almost 

 invariably throws off varieties, a convenient term for indicating a departure 

 from the parent type. 



From what has been said it will be evident that I consider a sport simply 

 a marked variety or variation, which may appear as a distinct individual or as 

 a part of an individual during its period of existence, in which case for 

 purposes of distinction we are pleased to call the latter a bud sport or variety. 



Sporting, then, may be encouraged by extreme conditions. Either extreme 

 feeding or extreme poverty may induce plants to sport. Severe changes in 

 climate or soil conditions may result in decided changes in stature, habits of 

 growth and faithfulness, which are as marked attributes of a sport as are changes 

 in the color of foliage or fruit. 



Burpee's dwarf lima bean is a good example of a sport where the habit of 

 the plant was markedly changed. The white and fancy sports of the Lawson 

 carnation are good illustrations of changes in color. Just here I wish to note 

 that in a bed of Lawsons and upon a plant with otherwise normal flowers one 

 shoot produced a blossom one-half of which was pure white, while the other 

 half was of the normal pink of the Lawson. These sports in the Lawson are 

 exceedingly interesting, for they clearly indicate that the Lawson is composed 

 of two parts, pink and white, in which the pink is the predominant. Under 

 favorable conditions, however, the white asserts itself, and we have the sports 

 above spoken of. This frequent breaking out of a recessive character is all 

 the more interesting in the case of the Lawson carnation on account of the 

 fact that neither of its immediate parents were white. The Lawson being the 

 result of a cross of Daybreak, pink, with Van Leewen, cerise. The facilities 

 now at hand do not allow me to analyze the composition of either Daybreak or 

 Van Leewen, but I suspect from the behavior of Lawson sports that one of 

 these and perhaps both of them have a strong white strain of blood in them. 



From what has been said it is evident that cross pollination is belived to 

 be one of the most important means through which the sporting or variation of 

 plants can be induced. The wonderful results obtained by Burbank in his 

 work with fruits has been based almost entirely upon the practice of cross 

 pollination. In connection with this work there seems to be two pretty well 

 established theories. They may be stated somewhat as follows : When working 



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