Burdick, A. B.
The following new mutants, recovered from various irradiation progenies, are described to the extent that present information will allow. They are all good seedling mutants and therefore may be quite useful in expanding the linkage map. Negative linkage results are given in-so-far as they are known and one case of linkage is reported.
a\325 anthocyaninless-325. An anthocyaninless mutant entirely similar to a and ag in phenotype; produced in Red Cherry line 0.18 by 18,000r X-ray of seed; originally designated m-1; completely recessive with normal gametic and zygotic viability; not allelic with ag, al, or a. a\325 has given the following negative F2 linkage tests (expected numbers for independence are given in parentheses):
Gene Parental Classes Recombination Classes Linkage
e 39 43 172 20 None
(51.3) (51.3) (153.9) (17.1)
c 46 47 150 14 None
(48.2) (48.2) (144.6) (16.0)
ag 176 222 None
(174.1) (223.9)
Wo 21 156 72 45 None
(24.5) (147.0) (73.5) (49.0)
H 72 70 197 18 None
(66.9) (66.9) (200.8) (22.3)
d 42 56 141 18 None
(48.2) (48.2) (144.6) (16.0)
a 160 198 None
(156.7) (201.3)
mo mottled-2. A recessive mottled chlorophyll type originally designated m-2;
produced in Red Cherry line 018 by thermal neutron irradiation (10 hrs. of 8 x
10^8 N\th\/cm^2/sec.) of dry seed; chlorotic spots are numerous and quite
small, the size being somewhat temperature dependent such that mature plants
in the field look distinctly yellow while those in the greenhouse in winter
look almost normal; seedling classification best at temperatures above 80 deg.
F.; gametic and zygotic viability normal; chronic doses of gamma irradiation
from 2 to 8OOr per day have no detectable effect on the size or frequency of
chlorotic spots; acute X-irradiation of mo seed up to 40,00r has no effect on
the size or frequency of chlorotic spots in seedling leaves so it appears that
the gene mo is stable although its phenotype is that of a typical genetic
instability. No linkage data.nd netted. A recessive seedling mutation that produces severely attenuated and chlorotic first leaves (although the cotyledons are normal) with later leaves having chlorophyll concentrated around the veins (hence, the name netted) and mature plant leaves almost normal; produced by 24000r X-irradiation of L. piminellifolium line 226 seed; originally called m-4; normal zygotic and gametic viability. nd is a chromosome 10 gene having given the following F2 linkage tests (expected numbers for independence are in parentheses):
Gene Parental Classes Recombination Classes Linkage
e 62 54 213 18 None
(65.1) (65.1) (195.2) (21.7)
Wo 25 170 97 55 None
(28.9) (173.5) (86.8) (57.8)
H 39 155 9 12 .1056+-.02
(13.4) (120.9) (40.3) (40.3)
M\345 mottled-345. A domimnt, homozygous lethal mutation that produce a
variety of types of large leaf sectors particularly in the first few leaves;
sectors are infrequent, probably no more than one per leaf, and range in size
from a few cells to 20% of the leaf area; best classified in the first two
leaves; may be hard to detect in mature plants; associated with only 33%
transmission probably as a result of reduced gametic viability; cytology
unknown; originally called m-163; gives the following F2 linkage results
adjusted for M\345 transmission (expected numbers for independence in
parentheses):
Gene Parental Classes Recombination Classes Linkage
e 147 22 88 56 None
(156.3) (26.1) (78.2) (52.1)
Wo 66 72 137 38 None
(69.5) (69.5) (138.9) (34.7)
yg\282 yellow-green-282. A recessive seedling mutation producing a chlorotic,
yellow-green plant under all usual conditions of greenhouse and field culture;
seedlings are etiolated with cotyledons standing more than twice as high as
normal plants; cotyledons chlorotic yellow-green also; seedlings frail but
mature plants vigorous; originally called m-19 and produced in L.
piminellifolium line 215 by 36 hours of thermal neutron irradiation (6.5 x
10^8 N\th\/cm^2/sec.) of seed; normal gametic and zygotic viability. No
linkage data.yg\333 yellow-green-333. A recessive seedling mutation producing chlorotic yellow-green plants under all usual field and greenhouse conditions; cotyledons are yellow-green, seedlings stunted and may die under some conditions (probably short photoperiod and/or low temperature); mature plants are fertile and slightly reduced in vigor; leaves are somewhat more deeply cut with slightly curled edges giving a "ragged" appearance to the plant; originally called m-123: produced in cadmium-pretreated, 15,000r X-irradiated Kokomo seed; normal gametic and zygotic viability with the possible exception noted above; gives the following F2 linkage results (expected numbers for independence in parentheses):
Gene Parental Classes Recombination Classes Linkage
c 35 33 93 7 None
(31.5) (31-5) (94-5) (10-5)
H 54 157 None
(56.6) (169.9)
l 46 165 None
(56.6) (169.9)
d 36 90 None
(31.5) (94.5)