Fruit setting rate
Taking into account the man-made and natural damage to the processed
inflorescences during the experiment, we selected 20 healthy
inflorescences from the harvest samples for fruit-setting statistics
(Fig 3).
Through a one-way analysis of variance, it was found that the fruit
setting rate was significantly correlated with pollination methods
(F=182.2, P<0.01; Figure 3a). Xenogamy (X, 47.0%) can
significantly increase the fruit setting rate than natural conditions
(OP, 35.8%), while the fruit setting rate under autogamy (SP, 5.7%)
and geitonogamy (G, 8.3%) was significantly lower than that under open
pollination (OP, 35.8%). The results revealed that V. negundo L.
var. heterophylla has self-compatibility and can successfully
produce offspring through selfing, but there was inbreeding depression
during the seed maturation process.
The anemophily (WP, 0.5%, Fig 3a) was also observed which can produce
offspring, although the fruit setting rate was very low. It was clear
that V. negundo L. var. heterophylla cannot carry out
spontaneously autogamy (SSP, 0%, Fig 3a), and the fruit setting rate
under this pollination mode was always 0 and there was no apomixes. Only
one of the four ovules of V. negundo L. var. heterophyllacan fully develop and bear fruit, and the fruit setting rate is
constantly at 25%.