Seed germination and vitality of ungerminated seeds
The 21-day seed germination of GM soybean, wild soybean, and hybrids are
shown in Fig. 1. In 2018, GM soybean had the highest total germination
rate (93.05%), while wild soybean had the lowest germination rate
(14.67%). The F1 hybrid germination rate was
intermediate between that of wild and GM soybeans, and there were
significant differences in seed germination between the
F1 hybrid and parental lines.
The germination of GM and wild soybean was similar in different years,
and the germination of F2 and F3 hybrids
was 53.67% and 38.33%, respectively. Both F2 and
F3 hybrids exhibited intermediate germination between
wild and GM soybeans, and significant differences were observed in seed
germination between F2 and F3 hybrids
and the parental lines.
At the end of the germination test, all nongerminated GM seeds were
found to be mildewed and rotten; in contrast, most ungerminated wild
soybean, F1, F2, F3seeds seemed normal and did not change in shape, size or color. These
seeds were evaluated for their ability to germinate after partial seed
coat removal, and the results showed that the five-day seed germination
of all observed wild soybean and hybrids was above 87.5% (Table 2).