Abstract
We conducted reciprocal interspecific crosses between Magnolia stellata and M. salicifolia and investigated whether there are differences in the development of fruits and seeds and the germination rate of seeds between reciprocal interspecific crosses. After 60-90 days from the hand pollination, the proportion of aborted fruits was higher for the interspecific cross of M. stellata as maternal parents than for that of M. salicifolia as maternal parents. Moreover, the fruit set, seed set and female reproductive success in the interspecific cross of M. stellata as maternal parents were all lower than those of M. salicifolia as maternal parents. The germination rate of seeds produced from the interspecific crosses in which maternal parents were M. stellata was lower than that in which maternal parents were M. salicifolia, but its difference was not statistically significant. Therefore, the occurrence of unidirectional interspecific hybridization in which M. salicifolia is a maternal parent and M. stellate is a paternal parent under nature conditions may be caused mainly by a failure in the fruit maturation and seed development in the interspecific cross of M. stellate as maternal parents.
