Brown: Influence of Stock on Cion 



157 



bloom from five to seven days or about 

 half the original difference between the 

 two on their own roots. 



Color and flavor of fruits is also 

 influenced more or less by the stock 

 used, but the results are not so easily 

 measured or as well understood. There 

 apparently is no question but that high 

 colored fruits can be improved by 

 grafting upon seedlings grown from 

 high colored fruits. This, however, is 

 more or less of an indefinite quantity, 

 as the seedlings themselves may vary 

 widely in their ability to transmit the 

 high color. Results are more noticeable 

 when seedlings from Siberian Crabs are 

 used, because they are more stable. 



What is true of color is also true of 

 the sugar and acid content of the fruit. 



Apples low in sugar when grafted 

 upon sweet apple trees will show an 

 increase in sugar content. Undoubtedly 

 some of the poor quality and lack of 

 color in certain regions, attributed to 

 local environment, may be due to the 

 influence of the stock on which they 

 are grafted. 



The cause of these varied influences 

 may be attributed to two sources — 

 namely, mechanical and physiological 

 disturbances. This can be more easily 

 understood when we think of the cell as 

 being the plant unit. Each cell per- 

 forms its own functions. Theoretically 

 the cells of the stock perform all those 

 functions characteristic of the stock, 

 up to the point of the union. Then the 

 cells of the other co-parent take up the 

 work and modify the nature of this work 

 — i. e., the vital processes — in accord- 

 ance with their own peculiar character. 

 While there is a rather wide division of 



labor in the functioning powers of the 

 cells of the different organs, there is a 

 more or less definite protoplasmic 

 organization throughout tfie entire plant 

 tissue. Certain cell substances such as 

 sugar may be differently affected by the 

 cells of each of the co-parents. If the 

 cells of the stock are capable of develop- 

 ing a higher sugar content than the cion, 

 presumably the cells of the latter will 

 not reduce it, hence a decrease or in- 

 crease in the acid or sugar content is 

 influenced by the stock. Of course this 

 is relatively a very small amount. 

 But if it were not for this, the entire 

 purpOvSe of graftage would be lost. 



In the case of dwarfed stock the cause 

 is more mechanical. The root system 

 of the slow growing plant is incapable 

 of supplying sap as fast as the more 

 rapidly growing top demands, hence a 

 reduction in size. Conversely, the 

 demands of the actively-growing top 

 stimulate the root system to a greater 

 effort, and thus cause an increase in the 

 size of the stock, as in the photograjjhs 

 here shown. 



The early bearing habit • of dwarfed 

 trees may be explained on the theory 

 that the diminished supply of sap tends 

 to weaken the whole tree. Now the 

 object of every plant, one may sa}^ is 

 to reproduce its kind ; and when it finds 

 itself weakening, it seems to hasten this 

 process of reproduction, in order to 

 make sure that it may leave progeny 

 before it dies. The dwarfed — and 

 weakened — tree thus blossoms and sets 

 fruit before its normal mates; and it is 

 correspondingly shorter lived, due to 

 this weakening, in consequence of the 

 mechanical restriction of the food .supply. 



Redfield Offer Remains Open 



At the request of the council of this Association, Casper L. Redfield has consented 

 to let his offer for data regarding the results of early marriage, stand open for 

 another year, or until December 31, 1915. It will be recalled that when the 

 original offer terminated on December 31, 1914, the council decided that none of 

 the evidence submitted met the stipulations. As the question of early marriage is 

 one of fundamental imi3ortance to eugenics, the council felt that a prolongation 

 of the offer might stimulate public interest in the subject and lead others seriously 

 to study it. 



