BOOKS AND CURRENT LITERATURE 



Preparation of Seed Potatoes. — One of the best station bulletins 

 that has appeared recently is the one from Maryland written by C. (). 

 Appleman. 1 In the practical application of a fundamental physio- 

 logical principle it is far ahead of the usual run of station bulletins. 

 It is scientific, exact, and yet so simply planned and presented that a 

 practical individual interested in better potato yields can understand 

 it. We need more station bulletins of this type. 



Appleman's bulletin on the Physiological Basis for the Preparation 

 of Potatoes for Seed has in view as "its chief object the preparation of 

 seed for the practical growing of potatoes. It deals with such ques- 

 tions as the relative values of the eyes on different parts of the tubers, 

 the size and form of the seed pieces, and the method of cutting the 

 tuber. These questions are discussed with special reference to the 

 influence of factors inherent in the tuber. Some of the more impor 

 tant conclusions may be summarized as follows: 



Terminal eyes suppress or retard the growth of other eyes on the 

 tuber. The degree of this growth inhibition is influenced by the vari- 

 ety, size of the tuber, vigor of the terminal sprouts and external 

 condition. 



It is these internal growth inhibitory influences which should receive 

 most consideration in formulating a practical procedure for cutting 

 the tuber for seed. 



Ej^es on the stem half of the tuber are capable of producing vigorous 

 sprouts, when their connection with the terminal eyes is severed and 

 they are just as valuable for seed, all other conditions equal, as the 

 eyes on the terminal or seed half of the tuber. 



The vigor of the sprouts depends upon the size of the seed piece. 

 Within certain limits, the yield of tubers increases directly with the 

 weight of the seed piece. The size of the seed piece can easily there- 

 fore become the limiting factor in the crop yield. The seed piece must 

 not weight less than 1.5 oz. 



1 Appleman, C. O. Physiological Basis for the Preparation of Potatoes for 

 Seed. Md. Agric. Exper. Sta. Bull. 212. 1918. 



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THE PLANT WORLD. VOL. ?2, NO. 3 



