Summary: | Hybrids between wheat and jointed goatgrass have long been presumed to be
sterile; however, seed were found on hybrid plants in 1990. Field studies were
conducted in 1995 and repeated in 1996. One to ten hybrid plants were planted in
variable populations of wheat and jointed goatgrass to determine the rate of seed set
and viability of seed produced on hybrids. An average of 2.3% of florets set seed in
1995 and 3.8% of florets set seed in 1996. Seed were set in all treatments. Hybrid
population had no effect on seed set. The BC1 (first backcross) seed produced in the
field studies were separated according to seed condition, full or shrivelled, and were
tested for germination. Ninety-four percent of the full seed germinated in each year
and 79% and 84% of the shrivelled seed germinated in 1995 and 1996, respectively.
Field studies were conducted in 1996 and 1997 using seed set on hybrids grown in
populations of 150 jointed goatgrass or 150 wheat plants in the previous year's field
study. Ten BC1 plants were planted into plots containing 100 jointed goatgrass plants.
From 0.25 to 20.29% of florets per plot set seed. Greenhouse studies were conducted
in 1997 and repeated in 1998 using BC1 seed produced in the previous year's field
study. Seed resulting from self-pollination occurred on 4.1% or 59 plants in 1997 and
2.1% or 16 plants in 1998. Percent seed set ranged from 0 to 80.22% on a per plant
basis. Parental population and seed set on BC1 plants can not be predicted based on
coleoptile color, germination day, leaf width, number of veins in the leaf, presence or
number of hairs on leaf margin, plant posture, number of spikes produced, culm
height, spike length, or resemblance to parents. === Graduation date: 1999
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