i86 
Journal of Agricultural Research voi. xxvii, no. 4 
made because the data show that ears selected from such diseased 
plants produced 46.6 and 42.7 per cent plants with the purple-leaf 
symptom, respectively, as compared with 5.9 per cent plants with the 
same symptom in corresponding ear rows from seed selected from appar¬ 
ently healthy plants (Table IV). 
Table VI. —Data on the occurrence of the purple-leaf symptom and on yield of Yellow 
Dent corn grown near Bloomington, III., 1920, in ear-row experimental plats from seed 
ears selected from plants having the purple-leaf symptom in IQIQ, the seed being treated 
with 1:1000 mercury bichlorid solution for one-half hour im'tnediately before planting 
(1920) 
Row No. 
Number of— 
Plants without purple- 
leaf symptoms. 
Plants with purple-leaf symptoms. 
Plants. 
Suckers. 
| Purple suckers. 
Number 
of— 
Yield. 
Number 
of— 
Yield. 
Number 
pro¬ 
ducing— 
Barren. 
Plants. 
Ears. 
Total. 
Average per 
plant. 
Plants. 
Ears. 
Total. 
Average per 
plant. 
Ears. 
Nubbins. 
Gm. 
Gm . 
Gm. 
Gm. 
11 
17 
9 
5 
S 
1,470 
294 
6 
s 
762 
127 
2 
3 
1 
14 
15 
11 
7 
7 
1, 856 
265 
7 
5 
1, 264 
181 
3 
2 
2 
3. 
17 
30 
6 
11 
11 
2, 614 
238 
6 
S 
i, 144 
191 
4 
1 
X 
17 
19 
12 
7 
7 
1, 7S4 
251 
10 
7 
I. 454 
145 
5 
2 
3 
16 
26 
13 
3 
3 
800 
267 
13 
12 
2, 202 
169 
6 
6 
I 
6. 
16 
24 
8 
10 
16 
2, 713 
271 
6 
5 
l, 166 
194 
3 
2 
I 
16 
12 
2 
12 
12 
3,086 
257 
4 
4 
i, 188 
297 
3 
1 
O 
8. 
IS 
23 
16 
7 
7 
2, 165 
309 
8 
7 
2, 296 
287 
7 
0 
X 
9. 
16 
20 
13 
7 
7 
2, 090 
299 
9 
9 
2, 372 
264 
8 
1 
0 
10. 
15 
9 
0 
12 
12 
3.372 
281 
3 
3 
746 
249 
3 
0 
0 
XI. 
II 
9 
4 
9 
9 
2, 788 
310 
2 
1 
304 
152 
1 
0 
1 
12. 
15 
17 
13 
11 
11 
3.026 
27S 
4 
3 
810 
203 
3 
0 
1 
X3. 
16 
13 
5 
7 
7 
1,484 
212 
9 
8 
1, 786 
198 
4 
4 
1 
14. 
II 
14 
3 
10 
10 
3. 488 
349 
1 
1 
290 
290 
1 
0 
0 
IS. 
6 
2 
0 
5 
5 
I, 612 
322 
1 
1 
346 
346 
1 
0 
0 
16. 
18 
27 
6 
14 
14 
4.320 
309 
4 
4 
1,122 
281 
3 
1 
0 
17. 
16 
12 
4 
12 
12 
3.170 
264 
4 
4 
1, 192 
298 
4 
0 
O 
18. 
18 
14 
3 
11 
11 
2, 9SO 
268 
7 
5 
i, 198 
171 
3 
2 
3 
19. 
i 4 
18 
IS 
4 
4 
940 
235 
10 
9 
1, 688 
169 
4 
5 
X 
20. 
13 
8 
S 
6 
6 
1, 450 
242 
7 
7 
1.104 
158 
2 
5 
0 
21. 
17 
37 
12 
8 
8 
2, 098 
262 
9 
7 
I, 730 
192 
6 
1 
2 
22. 
IS 
16 
4 
11 
11 
2, 980 
271 
4 
4 
1, 072 
268 
4 
0 
O 
n . 
14 
24 
15 
4 
4 
934 
234 
10 
8 
2,032 
203 
6 
2 
2 
Total. 
337 
396 
179 
193 
199 
S3, 160 
275-4 
144 
124 
29, 268 
218.8 
86 
38 
20 
Table VII. —Summary of data given in Table V , where seed was untreated, and Table VI, 
where seed was treated with mercury bichlorid solution 1:1000 for one-half hour. The seed 
in both cases was from the same ears selected from purple-leaf plants 
Points of comparison. 
Percentage of all plants that showed purple-leaf symptoms. 
Percentage of all suckers that showed purple-leaf symptoms. 
Average yield of apparently healthy plants. 
Average yield of purple-leaf plants.. 
Average percentage reduction in yield from purple-leaf plants.. 
Percentage of plants with the purple-leaf symptom that pro¬ 
duced ears.... 
Percentage of plants with the purple-leaf symptom that pro¬ 
duced nubbins... 
Percentage of plants with the purple-leaf symptom that were 
barren.. 
Table V. I Table VI, 
seed seed 
untreated 
treated. 
46.6 
42.7 
43 - 2 
45 - 3 
264.2 
3 75-4 
176.0 
218.8 
33-4 
30.6 
55 -i 
59-7 
27-5 
36.4 
17.4 
13-9 
