64 STATE HORTICULTURAL SOCIETY 



SELF-STERILITY AMONG CULTIVATED GRAPES. 

 BY PROF. S. A. BEACH OF GENEVA, N. Y. 



It has loug beeu known that some kinds of cultivated grape, either 

 form imperfect clusters or set no fruit at all when they are planted 

 alone. Because they are unable to fruit satisfactorily of themselves 

 they may properly be called self-sterile. 3Iany of the self-sterile grapes 

 yield abundantly when they are planted near enough to other kinds so 

 that their blossoms may be fertilized. 



A similar condition exists among cultivated strawberries. In the cata- 

 logues where strawberry plants are offered for sale the letters "p" or 

 "s'' are usually placed after the names of the varieties, to indicate 

 whether they are pistillate or staminate. The pistillate kinds have imper- 

 fect blossoms and can not fruit alone. To secure fruit from them it is 

 necessary to ijlant staminate varieties near enough to insure fertiliza- 

 tion of their blossoms. 



But there is quite a remarkable difference between the self-sterile 

 strawberries and the self -sterile grapes; for it is easy to see that the 

 strawberry has an imperfect blossom, while the fruiting grapevine 

 always bears perfect blossoms. 



An examination of the strawberr}' blossom shows at once that the 

 male organs, called stamens, either are wanting or exist only in rudi- 

 mentary form. In the self-sterile grapes the stamens are always pres- 

 ent and produce pollen. The only apparent structural difference 

 between their blossoms and those of self-fertile kinds is that some of 

 the former have short stamens. Even this difference is not always found, 

 for, as we shall show later, some self-sterile grapes iiave long stamens 

 like those of the self-fertile grapes. 



The extent to which self-sterility exists among American grapes is 

 evidently a subject of much practical importance to vineyardists, yet 

 it is only within recent years that it has been carefully studied. So 

 far as I know, the first accounts. of systematic investigations with grapes 

 in this line that were ever published were those issued in 1892, giving 

 the results of my experiments for that season. The work which was 

 then undertaken has been continued during each succeeding year with 

 as much thoroughness as time and opportunity would permit. 



The work has thus far been conducted solely in the vineyard of the 

 New York state experiment station, Geneva, N. Y., where the large 

 number of varieties which are readily accessible afford a very favorable 

 opportunity for making observations on this subject. 



About one hundred and fifty varieties have thus far been tested hero 

 as to their self-sterility. These include nearly all the important old 

 varieties and most of the promising new sorts. The results show that 

 there are many kinds of cultivated grape which can not of themselves 

 set any fruit, as for example, Brighton and Eldorado; other kinds form 

 i?mall, seedless, or abortive berries or imperfect clusters, as Duchess and 



