Fleshy Fruits in Liliflorous Monocots

Abstract

Fleshy fruits occur in several monocot orders and families, and it is generally assumed that they have been derived from capsular fruits many times during the evolution of monocot lineages. Huber hypothesized in 1969 that most capsules in Asparagales are derived secondarily from berries and that this transformation was correlated with the evolution of phytomelan-coated seeds, a pivotal character in his circumscription of Asparagales as part of reclassifying Liliaceae s.l. Dahlgren and co-workers suggested several parallel derivations and "reversals" in this character, e.g., the transformation sequence trifollicular fruits __... capsules __... berries __... capsules __... berries. Mapping of fleshy fruits on a phylogeny based on molecular characters indicates that Asparagales do not have fleshy fruits as a basal character. Dahlgren's "cyclic character evolution" hypothesis is not supported by the distribution of dry and fleshy fruits, and there is no obvious correlation between baccate fruits and phytomelaniferous seeds in Asparagales. Phytomelaniferous seeds are not an evident synapomorphy of Asparagales as presently circumscribed. The anatomy and development of different capsular and baccate fruits in selected genera are studied in an ongoing project to reveal homologies and establish an adequate fruit typology. Some observations of texture and dehiscence structures in dry and fleshy capsules and in typical berries from hypogynous and epigynous flowers are reported in this paper.

The South American genera of Hemerocallidaceae (Eccremis and Pasithea): two introductions to the New World

“…The fruit of Eccremis has been considered odd relative to other Hemerocallidaceae and often described from Krause (1930) onward as a loculicidal capsule with a septicidal endocarp (Clifford & al., 1998;Melcher & al., 2004). Our own observations on herbarium collections with mature fruit suggest a more typical hemerocallid or liliiflorous monocot morphology (Rasmussen & al., 2006) with an elongate, perhaps slightly succulent (fide collectors notes on Tillett 673-342, US), many-seeded loculicidal capsule (7-8 × 15-17 mm) that apically opens ca. 1/3 its length by splitting along the locules and also ripping apart the central placental column to release the ovoid seeds which are presumably then dispersed by capsule vibration (perhaps enhanced by the wind).…”

“…For the three fleshy-fruited genera, Dianella and Geitonoplesium each have strongly supported capsular sisters and Rhuacophila is placed with other capsular genera (weakly so in our trees but strongly with Stypandra in Devey & al., 2006). These probably represent 2-3 gains but possible losses and whether such losses could be detected through fruit structural changes is unclear (Rasmussen & al., 2006). Eccremis in particular should be further studied to see if it might be transitional (i.e., the succulence noted above).…”

“…36). The presence of phytomelan, which is interpreted as protective for seeds, is a possible synapomorphy for Asparagales, uniting the genera with capsules and those with berries (Dahlgren & Rasmussen, 1983;Rasmussen & al., 2006).…”

Micromorphology and anatomy of the flowers of Galanthus nivalis and Leucojum vernum (Amaryllidaceae)

“…The Amaryllidaceae family has the tendency towards formation of indehiscent fleshy capsules and berry-like fruits, which are seen repeatedly (Rasmussen et al, 2006;Takhtajan, 2009;Thadeo et al, 2015). This tendency was studied in different representatives with intermediate between dry and fleshy types of fruits among Monocotyledons (Rasmussen et al, 2006;Thadeo et al, 2015).…”

“…Therefore, as mentioned above, the fruits of G. nivalis are fleshy throughout their development and remain such during the dissemination. In the dorsal carpel bundle of G. nivalis, the xylem has a V-like shape, while such structure was not seen in the outer bundles of the dorsal veins (Rasmussen et al, 2006). The double pattern of dorsal bundles of the carpels and lignified inner layers are the most frequent features of the loculicidal capsules (Roth, 1977).…”