Bulbils contra seeds: reproductive investment in two species of Gagea (Liliaceae)

No sex at all? Extremely low genetic diversity in Gagea spathacea (Liliaceae) across Europe

“…and G. lutea Ker.-Gawl. (Liliaceae) in Western Pomerania (Germany), the former taxon showed extremely low genetic variation in the study region (Pfeiffer et al, 2011) and no seed set (Schnittler et al, 2009). Gagea spathacea seems to be sterile throughout its range, as reported by Raunkiaer (1895-99) and Westergård (1936) for Denmark, Gustaffson (1946, in Raamsdonk, 1985 for Sweden, and Levichev et al (2010) for several European countries.…”

“…Flowering (from mid April to early May) is scarce (1-3 flowers) and rare, usually only one in a thousand plants flowers. No evidence for apomixis is known for the genus; the species mainly reproduces vegetatively by formation of numerous subterranean bulbils (up to 54 bulbils per plant per year, Schnittler et al, 2009). Thorough searches (including regular control of plants marked at flowering) in several years and many German populations failed to detect fruit and seed set.…”

Morphological, reproductive and karyological variability in Allium oleraceum in Lithuania

“…Presumably, the ability of A. oleraceum to develop flowers depends on plant size, and vegetative reproduction is preferred when resources are limited. The precedence of vegetative reproduction versus seeds in plants with smaller bulbs is known in Gagea species (Schnittler et al 2009). According to Lanke et al (2010), plants allocate more resources to seed reproduction when available resources are limited, and with increasing resources more vegetative propagules are produced.…”

New insights into the phylogeny and taxonomy of Chinese species of Gagea (Liliaceae)—speciation through hybridization

“…Many species reproduce by bulbils, and their form, quantity and location provide important diagnostic characters (Levichev 1999b). Bulbil formation may be limited to non-flowering stages of ontogenesis, which is crucial for the balance between sexual and asexual reproduction (Schnittler et al 2009). Often, species possess morphologically similar juvenile stages but follow an ontogenetic pattern unique for each taxon.…”