Rick, C. M.
A complete deficiency for anthocyanin was discovered by Dr. I. C. Hoffman of the Ohio A.E.S., Wooster, Ohio in his lines of Globe A, Marhio, and Rutgers. It is believed that these were independent mutations. The appropriate crosses established that the genes in each were allelic with each other and not with a, ag, or al. Segregation in F2 from eight different crosses was 2338+ to 704 anthocyaninlees, with a significant deficiency of mutants. One family of 452 seedlings contributes most of this discrepancy, for, when its values are subtracted from the total, the remainders, 1960+:630 anthocyaninless, provide a good fit to 3:1. Even with this family removed, the data show a significant heterogeneity (X^2=17.5, p 0.01), which is attributed to variable survival at germination. Its monogenic inheritance being established, this new mutant is named Hoffmans anthocyaninless with the symbol ah. As far as we can ascertain under the various conditions that ah has been grown here, it fails to develop purple pigment and is therefore phenotypically identical with a and aw.
Linkage information for ah is summarized below. The only consistent indication of linkage is with wd. The evidence appears not only in the F2 phenotypic segregation but also in F3 progenies from wd F2 segregants (13 segregate for ah, 16 do not). The latter information provides an estimate of 29 units, the F2, 16. The best, though highly tentative, estimate is the mean of these values, 22 units. With this linkage, chromosome 9 is now provided with a much more useful marker than wd, which requires special environmental conditions for expression and cannot be readily classified in the seedling stage.
Contingency
Tester + + + t ah + ah t chi square co.
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c 128 39 64 14 0.62
c 209 67 79 24 0.004
cm 334 44 68 6 0.8
d 134 33 52 26 4.63
d 199 77 74 29 0.005
dl 111 32 31 8 0.001
dl 263 68 77 19 0.02
e 250 45 74 22 2.56
l 114 53 65 13 5.69
l\1 214 62 81 22 0.008
pr 237 90 51 23 2.0
rv 369 52 124 20 0.11
tf 231 64 65 31 4.00
wd 97 46 38 1 12.5 1660 +- 5.0
Wd^m 83 212 19 77 2.20
yv 125 18 31 8 1.14