Oil yellow Oily yellow green seedling and plant; many alleles with phenotype & dominance ranging from null deep yellow lethal through white, oil yellow, bright oil yellow green & vigorous yellow green near normal; major effect is absence of chlorophyll b

Oil yellow dominant allele: First two leaves of F2 progeny of Oy1-700/+ sibbed (left to right) normal, Oy1 homozygote, and Oy1/+ heterozygote seedlings, showing respectively, normal green, pale yellow lethal and deep yellow green leaves.

oil yellow First two leaves (left) of dark yellow, oy*-N195, M2 mutant seedling

oil yellow homozygous recessive oy1-ref viable allele showing bright yellow with slight oily appearance. See other allelic and interaction phenotypes: oy1-Masia 1040, null deep yellow lethal; oy1-tn viable dark yellow green viable; Oy1-N700, bright oily yellow green vigorous heterozygote, yellowish white lethal seedling homozygote; Oy1-N1459, like 700 but weak heterozygote and near albino homozygote; Oy1-N1460, like 700 but strong yellow green heterozygote that becomes normal at maturity and a weak lethal yellow seedling homozygote. The heterozygous combination Oy1-N700/oy1-tn has a deep yellow lethal phenotype like the null. An observation; most diploid plant species have one gene system like Oy1; hexaploid wheat has 3 one in each genome (Chlorina, Sears , get reference) See full Oy1 story in Oy1-N700 entry

Oil yellow allelic interaction: First two leaves of seedlings from the cross of +/oy1 x +/Oy1-700, showing (left to right) yellowgreen; Oy1-700 heterozygote; normal; and bright yellow Oy1-700/oy1 heterozygote.

Oil yellow Chimera: An immature half-plant chimeric greenish brilliant yellow, Oy1-N1459, M1 mutant origin plant , showing consequence of EMS-induced mutation in two-stranded sperm nucleus of treated pollen grain

Oil yellow Seedling progeny from cross of chimeric Oy1-1459/+ mutant M1 origin plant by normal pollen, showing 1:1 segrgation of brilliant yellowgreen seedlings, indicating inadvertent selection of Oy sector on ear.

Oil Yellow revertant sector: Two Leaves of an Oy*-N2515/+ heterozygous backcross mutant plant showing yellow green each with a normal green longitudinal chimeral sector indicating some instability of this allele. Possibly of spontaneous origin. Homozygote is yellowish white lethal seedling.

Oil yellow Oy1, wt1 interaction: Progeny from the cross of Oy*-N2553/+ on W23, +/wt1 showing a uniform whitish bright oil yellow Oy/+, +/wt1 plant indicating that Oy/+ and +/wt interacts to enhance Oy phenotype even though wt1 is considered a recessive and affects leaf color in leaf tip and crossbands in homozygote only. This particular Oy1 mutant allele normally greens up quite rapidly so that it is nearly normal at flowering. Emerging leaf whorl is yellow green but fully exposed leaves are near normal green.

Oil yellow Chimera: Top whorl of leaves of Oy*-N2294/+ heterozygous chimeral M1 origin plant, showing much less than a half-leaf sector of normal green tissue; probably the remnant of a half-plant sector in which the mutant portion predominated. This mutant may be a less bright allele of Oy1 that greens up more rapidly until it is nearly normal green at maturity.

Oil yellow chimera: Half-plant Oy*-N2294 chimeral mutant origin seedling, showing green one-half of first leaf and one-fourth of second leaf, showing chance developmental predominance of mutant tissue