University of Nebraska
1992 Wheat Technology Conference
Jointed goatgrass can and does spontaneously cross with wheat. As wheat is self-pollinated, these crosses are extremely rare. However, under conditions that lead to male sterile wheat (stress, frost, hybrid production fields, etc.) crossing levels will be higher. The hybrid between jointed goatgrass and wheat is usually sterile, though the sterile hybrid can then be crossed by wheat and form seed. Fortunately, goatgrass has barriers to hybridization and later generations are almost always sterile. Because there is so much wheat in relation to jointed goatgrass, most of the hybrids are between wheat as a female and jointed goatgrass as male. Hence genes from jointed goatgrass are diluted in the wheat. Little information is available on hybrids between jointed goatgrass as a female and wheat as a male. In this case, the wheat genes could be transferred to jointed goatgrass which could be harmful if they were for herbicide resistance or improved the weed’s survival.
Two questions are usually asked about wheat and jointed goatgrass: 1. Will wheat or jointed goatgrass breakdown and release its progenitor species? and 2. If the origin of wheat and jointed goatgrass are from the middle east, how did they get to the united states? The answer to the first question is no. Wheat (or for that matter the manmade hybrid, triticale) will not breakdown into to its progenitors. Wheat (and triticale) are reproductively stable. As for the second question, wheat was brought to the United States by immigrants. In the wheat seed there was also seed of common weeds, in this case jointed goatgrass.