804 EXPERIMENT STATION RECORD. 



in the selectiou of seed is urged. Analyses show tliat peanut hay and 

 peanut cake have a, hii^h feeding' vahie. 



Originating varieties of potatoes, U. Lieuscher {Jahrb. dcut. 

 landw. Ges., !) {1894), pp. 303-318).— The theory and history of phiut 

 breeding are discussed at some length. Modern potato breeders se- 

 lect as parents 2 varieties which in most qualities bear close resem- 

 blance to each other, avoiding the use of opposites. Their aim is to 

 secure as much similarity as possible in most of the qualities of the 

 l)arents, attempting to iix one characteristic at a time. 



This is somewhat in contrast with earlier practice, in which varieties 

 ditfering widely were crossed. As an instance of the advantages ot 

 the modern method, which gives a smaller amount of variation in the 

 seedlings produ(;eil, one potato breeder stated that under the earlier 

 system he sometimes grew annually several tliousand seedlings, only 

 1 per cent of which was worthy of a second year's trial, while by cross- 

 ing varieties similar in most qualities as many were secured by grow- 

 ing only 300 to 500 seedlings, of which 50 to 70 per cent usually [)roved 

 worthy of further trial. 



Breeders no longer expect to get certain qualities from the female 

 parent and certain others from the male. 



The interrelation of different qualities is not well known, but it has 

 been noted that a variety having few thick stalks affords only a small 

 number of tubers, which are large; one having numerous slender stalks 

 bears numerous tubers, which naturally remain small. Violet-colored 

 stalks indicate colored tubers; white liowers generally, but not always, 

 acconqiany white tubers. Early ripening and resistance to disease are 

 not generally found together. A large lu'oduction of true seed is believed 

 to go hand in hand with a small production of tubers. 



Wliether or not the time of ripening of a variety can be changed 

 by selection and by varying the time of planting is a mooted question 

 among potato breeders. 



In pollenizing varieties artificially the stamens should be removed 

 from the female parent with fine pinchers Just as the bloom opens, and 

 the tiower inclosed in a paper or gauze bag. The proper stage for 

 applying the pollen is indicated by the moist appearance of the stigma. 

 The pollen from the desired v^ariety should be dusted on the stigma 

 on 2 or 3 successive days, so as to make sure of fertilization. The bag 

 is removed as soon as the stigma dries and the bloom withers. 



The seeds are washed out from the ripe seed balls, dried, and at the 

 I)roper season sown shallow under glass. The seedlings are first trans 

 planted in a hotbed, and later the strongest plants are placed in a rich 

 bed out of doors. Tlie distance between the seedlings varies from 12 

 by 12 in. to 20 by 2G in. The old rule that in the first year the seed- 

 lings should produce tubers of the size of a hazelnut, in the second 

 year of walnut size, and normal tubers not before the third year is no 

 longer applicable. In one instance a seedling i)roduce(l the first year 

 tubers weighing about 2U0 gm. (over 7 oz.). 



