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