3.
Tryptophane, niacin and indoleacetic acid in endosperm mutants.
Assays of the tryptophane, niacin and indoleacetic acid (heteroauxin) levels in several endosperm mutants have been carried out. Degermed kernels from segregating ears were used for assay. The "normal kernels" were a mixture of genotypes. Hence, if any endosperm gene was incompletely recessive in its biochemical effect, then the differences in the table may not represent maximal ones. At least three samples of each character except mn were assayed. Average values are cited in the accompanying table. Three inbreds are listed for comparison. Brittle‑1, shrunken‑1, and shrunken‑2 therefore are similar to sugary‑1 in their effect on tryptophane, niacin and indol acetic acid levels. Possible bases for these differences are being studied ontogenetically.
|
|
Tryptophane |
Niacin |
Indoleacetic acid |
|
Kernel type |
micrograms/gm |
micrograms/gm |
micrograms/gm |
|
wx |
249 |
40 |
43 |
|
normal |
338 |
33 |
41 |
|
su |
521 |
50 |
25 |
|
normal |
395 |
27 |
12 |
|
bt1 |
888 |
108 |
61 |
|
normal |
479 |
21 |
24 |
|
sh1 |
420 |
51 |
29 |
|
normal |
281 |
32 |
19 |
|
sh2 |
1037 |
92 |
36 |
|
normal |
420 |
26 |
9 |
|
mn |
382 |
28 |
1 |
|
normal |
238 |
25 |
16 |
|
Inbreds |
|
|
|
|
L317 |
175 |
11 |
8 |
|
CC5 |
190 |
34 |
6 |
|
WF9 |
376 |
25 |
68 |
H. J. Teas and Anna C. Newton