Nov. 15,1925 Crown-gall Studies of Resistant Stocks for Prunus 
965 
by the small size and characteristic shape of the galls, is demonstrated 
by the small number that develop. These characteristics of gall 
development have been observed (3) in other resistant species, 
especially in the case of P. domestica (Italian prune and German 
prune) (pi. 3, B to E). 
Table V.— Summary, by years of inoculations, on different introductions of Prunus 
mume 
Year 
S. P. I. 
28685 « 
(1) 
S. P. I. 
43558 “ 
(1) 
S. P. I. 
45523 « 
(21) 
S. P. I. 
46694 <* 
(12) 
S. P. I. 
47950 « 
(ID 
1916....... 
*30 0 
120 10 
120 16 
60 1 
20 0 
70 5 
80 8 
1917____ 
1918___ 
1919_____ 
*40 8 
20 0 
70 8 
50 0 
*70 13 
1920____ 
*150 0 
620 20 
810 4 
*600 34 
260 20 
530 2 
1921..... .. 
420 54 
840 122 
1922____ 
Total.. ... 
500 40 
180 16 
1,330 189 
1,580 24 
1,390 56 
• 
Per cent of galls... .. 
8.0 
8.9 
14.2 
1.5 
4.0 
« The calalogue number assigned by the Office of Seed and Plant Introduction, Bureau of Plant Industry, 
United States Department of Agriculture. The number in parentheses indicates the number of different 
seedlings inoculated. 
* The first number indicates the number of inoculations, the second the number of galls that developed. 
On the more susceptible introductions of Prunus mume the galls 
are much larger and subglobose in shape. They are similar to typical 
crown galls that develop on other hosts from artificial inoculations. 
Table VI .—Number of galls which developed in each series of 10 punctures in 
inoculated species, resistant and susceptible, of Prunus and Amygdalus 
Species 
Common name 
Number of galls developing from each 10 punc¬ 
tures ° 
P. domestica_ 
Italian prune_ . 
0, 1, 0, 0, 0, 0, 0, 4, 0, 2, 0, 0, 2, 0, 0, 3, 0, 0, 0, 0, 1, 0 
0, 0, 0, 0, 6, 0, 0, 6, 0, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0. 
1, 0, 2, 2, 0, 0, 4, 0, 0, 0, 0, 0, 0. 
0, 0,0, 0, 0, 0, 0,1, 0, 0, 0, 0, 0, 0, 0, 0, 0,0,0, 6, 0, 2, 
2, 0, 2, 0, 0, 0/0, 1, 0, 0,1. 
3, 0,3, 8, 7, 6,0, 5,3, 5,1, 0, 0,1,4,4,1,0, 0, 2,1, 0, 
0,1, 0, 1, 0, 0. 
10, 0, 0, 5, 0, 0, 6, 6, 7, 4, 3, 4. 
0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 5. 
0, 3,1,0,1,0, 0,0,0,1,1,4,0,1, 0, 6, 6,1,0, 0, 0, 0, 
1, 0, 0. 
10, 8, 9, 8, 5, 8, 0, 4, 2, 4,10, 2. 
10, 10, 9, 7, 10, 8, 10,10,10, 10. 
9, 10, 10, 10, 9, 0,10, 10, 7, 8, 0,10, 10,10,10. 
8,10, 0, 2, 0, 0, 0, 0, 0, 0, 8, 7, 0, 4, 0. 
10, 10,10, 9, 9, 10,10, 8, 0, 2,10, 8, 0. 
P. domestica- .. 
P. besseyi_ 
P. mume... 
P. mume..... 
P. angustifolia watsoni.. 
P. alleghaniensis_ 
A. tangutica__ 
P. cerasifera- 
P. cerasifera divaricata... 
A. persica___ 
A. communis_ 
German prune__ 
Sand cherry (Rocky Moun¬ 
tain Dwarf). 
S. P. 1.46694 (Japanese apri¬ 
cot.) 
S. P. 1.47950 (Japanese apri¬ 
cot.) 
Allegheny plum__ 
Chinese wild almond_ 
Myrobalan plum_ 
Elberta peach.. 
Bitter almond_ 
A. davidiana_ 
Davidiana peach_ 
• Data do not include all the inoculations that were made. 
Hiker (#), experimenting with some inoculations on tomatoes, 
found that the size of the original puncture determined the size of 
the gall. The difference in size of the original puncture could hardly 
explain the relatively small size of the galls that developed on the 
resistant trees of Prunus mume as compared with the larger ones 
that appeared on the susceptible trees, since in all these inoculations 
a steel needle of the same size was used. The resulting wounds on 
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