96 
Journal of Agricultural Research voi. xxvn, no. 2 
80 per cent germination of the 435 Haberlandt seeds, and 88 per cent 
germination of the 151 Feldun seeds. Although lower percentages of 
germination occurred in some of the other varieties, there was no marked 
reduction of germinating power in the larger lots of seed nor was the 
germinability in any way correlated with the percentage of mosaic 
in the seedlings. The latter also holds true for older seed as shown in 
Table IV. 
In field plots planted in 1921 with 370 seeds from mosaic plants only 
61 per cent germinated. The relative germinability of the seed from 
mosaic and healthy plants grown in 1922 was tested in the greenhouse 
and the results, as shown in Table VI, indicate that mosaic had little if 
any influence on the germinating power of seed. 
Table VI .—Effect of mosaic on the germinating power of seed 
Variety. 
Seed from healthy plants. 
Seed from mosaic plants. 
Number 
of plants. 
Number 
of seeds. 
1 
Per cent 
germina¬ 
tion. 
Number 
of plants. 
Number 
of seeds. 
Per cent 
germina¬ 
tion. 
Per cent 
mosaic. 
Haberlandt. 
8 
176 
74 
8 
137 
7 1 
7 
A. K. 
2 
45 
78 
3 
21 
8l 
12 
Lexington. 
3 
80 
66 
3 
39 
59 
0 
Feldun. 
2 
5 1 
63 
2 
39 
54 
0 
EFFECT OF MOSAIC ON YIELD OF SEED 
Reddick and Stewart (7) found that bean mosaic suppressed seed pro¬ 
duction, and Dickson (3, p . 18-ig) has recorded a marked reduction in 
yield of seed due to mosaic in pea beans, broad beans, and red clover. 
As the writers (5) have previously reported, reduction in yield of seed is 
likewise one of the outstanding features of soybean mosaic. In the fall 
of 1921 a comparison was made of the yield of seed from mosaic and 
normal plants and the results, as presented in Table VII, show that 
mosaic caused a very serious reduction in yield, especially in the Haber¬ 
landt variety. 
The comparative yield of healthy and diseased plants in the variety 
plots in 1922 is shown in Table VIII. The mosaic seedlings had been 
tagged so that it was possible to record whether the disease was of seed 
origin or the result of secondary infection during the season, and except 
in the Midwest variety, the mosaic was all of the latter type. 
Table VII .—Effect of mosaic on yield of seed, IQ21 
Variety. 
Healthy. 
Mosaic. 
Number cf 
plants. 
Average 
yield per 
plant in 
grams 
Number of 
plants. 
Average 
yield per 
plant in 
grams. 
Per cent 
reduction 
in yield. 
Midwest. 
24 
14.59 
27 
9 - 5 8 
34 
Haberlandt. 
5 
41.57 
9 
IO.96 
76 
Arlington. 
3 
7.65 
3 
4.60 
40 
Lexington. 
2 
12.01 
2 
4.82 
60 
