Field observations of M2
-generation offspring of regenerated plants
In 2012, we sowed the seeds harvested in 2011 so that the identity of each seed with
respect to its source plant was maintained. The field, which was the same field used in 2011,
was ridged and covered by plastic film, with 90 cm between adjacent ridges. Each ridge was
planted with two rows of seeds, with one seed per planting hole and 17 cm between adjacent
seeds in the row. At the same time, seeds of the mutagenic parent, Luhua 11, were planted
as the control group. The M2
-generation offspring plants were evaluated for variation rate in
seedling vigor, plant height, branch number, pod number, pod shape, and other traits during the
growing stages and at harvest. The trait variation rate was calculated as follows: