In general, sunflower is considered self-fertile and a self-pollinated
crop, but lack of self-compatibility considerably declines its yield (Neff and Simpson, 1990; Free, 1993).
Manually cross-pollinated flowers produced the highest number of seeds, followed by flowers exposed to natural pollination and manually self-pollinated
flowers; however, the differences were not statistically significant among them (Table 1).
Self-compatibility and autonomous self-fertilization.--To determine whether Galax is self-compatible and whether the degree of self-compatibility differs between cytotypes, we self-pollinated
flowers on six plants in single cytotype populations and three diploid and three tetraploid plants in mixed cytotype populations.
Cereal crops such as wheat, rice and corn are either wind or self-pollinated
and do not require insect pollination.
stigmas were excised with the aid of a manual retractable cutter and immediately self-pollinated
. The thickness of the excised portion was approximately 1.5 mm.
However, we found the strategy couldn't effectively discriminate self-pollinated
off-types from those true hybrid individuals.
Hermaphrodite trees grown in Jordan also produce a high number of flowers per raceme (26 flowers/raceme), but set very low pods even when self-pollinated
with pollen on the same flower and/or the same tree or crossed with pollen from other trees.
Rice, our most important crop, and legumes such as mungbean, peanut, sitao, and solanaceous crops like tomato, eggplant and pepper are naturally self-pollinated
. Corn is naturally cross-pollinated, but by air/wind movement.
Furthermore, the scientists demonstrated that the composition of nutrients differs depending on the pollination mode: Nuts from the self-pollinated
trees contained a lower proportion of linoleic acid but a higher proportion of vitamin E.
Because our previous study indicated that the number of germinated pollen grains on chrysanthemum stigmas reached the peak at 24 h after artificial pollination, we thus here collected the self-pollinated
inflorescences at 24 h after pollination in the artificial self-pollinated
These four crops plus lettuce also are naturally self-pollinated
, which means each plant is pollinated primarily from its own pollen rather than traveling insects, making it much easier to maintain distinct varieties.