Kcprinted, without change of paging, from Journal of Tue New York 

 Botanical Garden 26: 25-31. 1925. 



SELF-INCOMPATIBILITY IN WILD SPECIES 



OF APPLES 



Certain individuals of some of the wild species of apples are 

 self-incompatible and require cross-pollination for the setting of 

 fruit quite as do many of the cultivated clonal varieties of this 

 fruit. 



Tests which show this condition were made in the orchards 

 of the State Experiment Station at Geneva, N. Y., during the 

 year 1924. For these tests the bagging method was employed. 

 Branches with several clusters of flowers, all yet in bud, were 

 enclosed in paper bags securely tied at the mouth to prevent en- 

 trance of foreign pollen. The bags were left thus for about 

 three weeks, when the paper bags were replaced by bags of net- 

 ting in case fruit was setting. The period during which the 

 paper bags remained on the branches coincided with that of 

 other pollinations at Geneva in the breeding work with apples. 

 The method of testing is one frequently employed in similar 

 studies and in breeding work with the various fruit plants. With 

 such treatment, the enclosed flowers open fully, shed pollen 

 freely, are evidently well pollinated through the movements of 

 branches and bags in the wind, and when fully self-compatible 

 set fruit abundantly. 



A single tree of each of thirteen species and two trees of one 

 species were tested. The specific names here used are those 

 with which the scions from which the trees were grown were 

 labelled when received at Geneva from the Office of Foreign 

 Seed and Plant Introduction, U. S. D. A., or from other sources. 

 From three to ten bags were used per tree, with each enclosing 



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