Crepis can reproduce sexually or
asexually.
Crepis is
insect-pollinated, typically by
bees and other generalist pollinators. Species in this genus are able to produce viable seeds through
hybridization. Some of these hybrids (depending on their parent species) can reproduce themselves. As an aster, flowers of
Crepis are closely clustered on a
capitulum, which is surrounded by petal-like
rays. Asexual reproduction (or
autogamy) between flowers on the same capitulum has been observed in the genus.
Apomixis in Crepis As with several other genera in
Asteraceae, multiple
Crepis species exhibit
apomixis, a form of asexual reproduction where flowers produce clonal seeds without need of fertilization. Unlike sexually-reproducing individuals, which are
diploid, apomicts are typically
polyploid, with three or more sets of chromosomes. The mechanism of apomixis in
Crepis is apospory, wherein diploid tissue arises during
meiosis in the
ovule. Through apospory, asexual seeds can develop spontaneously in the flowers of a non-apomictic
Crepis.
Crepis is part of the
Cichorieae tribe in Asteraceae, and is one of several genera of that tribe that exhibits apomixis. The largest group of asexual species is found in
North America, and is referred to as the "North American
Crepis agamic complex" At least one Eurasian
Crepis species,
C. tectorum, has been observed to self-fertilize. Species known to produce apomicts in
clude C. acuminata, C. barbigera, C. intermedia, and
C. occidentalis. Polyploid individuals may still be able to carry out sexual reproduction and therefore produce sexual offspring, allowing for the formation of new polyploid hybrids. The mixed apomict-sexual parantage may produce a polyploid hybrid (as has been observed when the apomictic
C. barbigera breeds with diploid species
C. atribarba). Seed set in the diploid may be reduced, or the pollen may produce hybrid seeds that are unable to reproduce or survive to a normal lifespan. The pollen from the apomict may also prevent germination of pollen from a diploid flower. When pollen from a polyploid individual fertilizes diploid flowers, the resultant seeds are typically polyploid, which lowers the diploid population over generations. Additionally, some
Crepis apomict species have the ability to hybridize with other apomicts, resulting in genetic recombination alongside
parthenogenesis. ==Uses==