TWIN AND TRIPLET PEACHES 



C. H. Connors 



Ah'w Jersey AyricuJtiiral Ilxper'uuent Station. Ncxv Bninswick, N. J. 



THE OCCURRENCE of d()ul)le 

 fruits on peach trees is not 

 uncommon in any season, but 

 certain seasons seem to bring forth 

 larger numbers. Blake and Connors' 

 reported the large numbers found in 

 the experimental orchards at Vineland, 

 N. J., in the season of 191 5. These 

 were not in such large proportion as 

 those reported by Karper." 



Multiple fruits may occur liy two 

 methods, and by combination of these 

 two methods. The peach more fre- 

 <quently than not sets three buds at a 

 node, two blossom buds with a leaf 

 1u:d between. In some cases, three and 

 four flower buds are formed at a node. 

 Frequently, twin flowers are formed, 

 originating from a single bud and upon 

 the same pedicle (Fig. 15). The two 

 conditions are not easily confused. The 

 stigmas of the twin flowers usually 

 become receptive simultaneously, and 

 may be pollinated at the same time. 

 Given normal conditions following pol- 

 lination, the ova will be fertilized and 

 the fruits will develop at approximately 

 the same rate, resulting in more or less 

 symmetrical twin fruits. 



The second method is by multiple 

 pistils. As is well known, peach blos- 

 soms have normally only one pistil, 

 but Figure 16 depicts blossoms having 

 •one, two, and three pistils, and Figure 

 15 shows immature fruits developed 

 from such blossoms. The writer has 

 never seen more than three pistils in 

 the blossoms of the edible peaches, but 

 the ornamental double-flowered forms 

 Tnave from one to six pistils. In the 

 course of emasculating and pollinating 

 more than 10,000 peach blossoms dur- 



ing the spring of 1922, opportunity was 

 given to study the development of mul- 

 tiple pistils. All gradations were 

 found. The first step appeared to be 

 fasciation of the stigma, then a fas- 

 ciated style ; the next gradation ap- 

 peared to be two stigmas on a fasciated 

 style, then two stigmas and styles upon 

 a fasciated ovulary and finally, two 

 distinct pistils. Very frequently, how- 

 ever, one pistil is less developed than 

 the other, and probably is never pollin- 

 ated, resulting in either a single fruit 

 or else the pericarp develops very slow- 

 ly, resulting in some of the odd forms. 



By combining these two forms, a 

 twin flower, one of the members of 

 which is double pistillate, might give a 

 triple fruit as well as a single flower 

 with three pistils ; twin flowers with 

 both members double pistillate might 

 give quadruple fruits ; and so on. 



In the first figure of the paper by 

 Karper, what appears to be a quadruple 

 fruit, judging by the illustration, is 

 really not a quadruple fruit on a single 

 pedicle, but seems to have been formed 

 from the usual three bud formation, 

 in which the blossom buds each devel- 

 oped into twin blossoms, resulting in 

 double fruits, while the leaf-bud failed 

 to develop, allowing the two double 

 peaches to come into intimate contact 

 in such a way that a quadruple fruit 

 seemed to be formed. 



The range in development attained 

 in double fruits is shown in Figure 

 17 in which six specimens are shown 

 whole and in section. It will be noted 

 that in the case of one fruit, at least, 

 the growth appears to be purely vege- 

 tative. Possiblv the ovum was not 



^ Blake, M. A., and Connors, C. H. Odd Forms of Peaches. N. J. Sias. Rcpt. 

 1916, p. 78. 



-Karper. R. E. Compound Fruits of the Peach Resulting from Multiple Pistils. 

 Journal of Heredity, xii :402-406. 1921. 



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