Itsepölyttymistä

Itsepölyttymistä, a Finnish term, refers to self-pollination in plants. This process occurs when pollen from a flower's anther fertilizes the ovule of the same flower or another flower on the same plant. It is a form of sexual reproduction, though it is genetically similar to asexual reproduction as the offspring are often genetically identical to the parent plant.

Many plant species are capable of self-pollination, including a significant number of crop plants like wheat, barley, and tomatoes. This reproductive strategy can be advantageous in environments where pollinators are scarce or unreliable, as it ensures reproductive success. It can also help to maintain desirable traits within a plant lineage.

However, self-pollination can also lead to inbreeding depression, a reduction in fitness and vigor due to the increased likelihood of homozygous recessive deleterious alleles becoming expressed. Over generations, this can weaken a plant population. Many plants have evolved mechanisms to prevent self-pollination, such as dichogamy (temporal separation of anther and stigma maturity) or self-incompatibility, where the plant's own pollen is rejected. Despite these mechanisms, self-pollination remains a common and important reproductive strategy in the plant kingdom.