Inhibition of The Brachytic Dwarfing Gene in Penisetum Americanum × P. Purpureum Crosses

Two Pennisetum purpureum Schum. strains 'Merker 300086′ and ‘Taiwan’, were crossed with a brachytic dwarf P. americanum (L.) Leeke mutant and its tail counterpart. The plant height of the four interspecific hybrids did not vary according to the variation in height of the parental P. americanum lines. This indicated that the expression of the brachytic dwarfing gene was inhibited by the P. purpureum genomes which could be attributed to the involvement of dominance and/or epiestasis among the genes controlling plant height in both the parental species.