Abstract
Four yellow-green leaved variants were found in Nakei No.5 orchardgrass. Two of these variants and their hybrids were used in the experiment conducted to clarify the inheritance of the character with back- and sib-cross methods. The character was inherited tetrasomically with a lethal recessive gene. Nulliplex yellows were recessive to normal duplex, triplex and quadruplex greens, and died in the cotyledonous or the first leaf stage. Yellow-greens were mostly simplex with some exceptional duplex plants. The existence of duplex yellow-greens indicated that the dominance of greens to yellows were not so fully established and were subject to inverse. Random chromatid segregation was suported because of the production of some yellows in hybrids between duplex and triplex greens.
