570 FUNDAMENTALS OF FRUIT PRODUCTION 



stock, forms aerial stolons freely. The combination plant grows vigorously 

 and manufactures much starch which cannot go into tuber formation as 

 it would in an ordinary potato plant. It is, therefore, because of the 

 vigor of the stock, utilized in the conversion of the potato stolons into 

 leafy shoots. On a weakly growing stock, however, such as Capsicum 

 annuum, starch accumulation exceeds utilization and tuber formation 

 ensues from the buds which on Datura stocks give rise to shoots. 



Fruit-bud Formation. — Voechting^^^ "has shown that buds which grew 

 from the base of the inflorescence of a beet in the second year came out as 

 leafy shoots supplied with large leaves, if they were grafted on a 1-year 

 beet; on the contrary, they infloresced if they were placed on a stock 

 already in its second year." 



Leclerc du Sablon^^ shows differences in total carbohydrates in 

 the tops of Angouleme 2 years grafted on pear and on quince stocks. 

 Except in May the carbohydrate content of the pear on quince is higher 

 than that of the pear on pear. In view of the importance of carbohy- 

 drate content to fruitfulness this difference seems of possible signifi- 

 cance, though it is comparatively slight at the ordinary time of fruit 

 bud formation. 



Table 3. — Total Carbohydrates in Tops of Angouleme Pears Grafted on Pear 



AND on Quince 



(After Leclerc du Sahlon^'^) 



(Per cent, on dry weight basis) 



On Pear On Quince 



Jan. 19 23.7 25.9 



Feb. 26 21.7 25.4 



Mar. 28 24.3 27.9 



May 9 21.6 21.3 



June 17 22.2 22.6 



July 22 22.6 22.9 



Sept. 7 24.5 25.8 



Oct. 16 23.4 25.4 



Nov. 22 23.4 25.3 



Dec. 26 23.4 25.5 



Specific citations are hardly necessary to show the influence of 

 certain stocks on fruit-bud formation. The dwarfing stocks, through 

 limiting growth and therefore carbohydrate utilization, have a general 

 tendency to permit sufficient carbohydrate accumulation for free forma- 

 tion of fruit buds. European and Japanese chestnuts, for example, 

 worked into chinquapin, bear in 1 or 2 years. ^^ It should be remem- 

 bered, however, that the total framework on which fruit buds can be 

 formed is smaller and the total production of fruit buds on a given area 

 of ground is not necessarily greater and may even be smaller, when 

 dwarfing stocks are used. In some cases certain stocks not dwarfing 

 in themselves make poor unions with cions set in them and exercise a 



