Endozoochorous dispersal by herbivores and omnivores is mediated by germination conditions

Seed traits matter-Endozoochoric dispersal through a pervasive mobile linker

Although many plants are dispersed by wind and seeds can travel long distances across unsuitable matrix areas, a large proportion relies on co-evolved zoochorous seed dispersal to connect populations in isolated habitat islands. Particularly in agricultural landscapes, where remaining habitat patches are often very small and highly isolated, mobile linkers as zoochorous seed dispersers are critical for the population dynamics of numerous plant species. However, knowledge about the quali- or quantification of such mobile link processes, especially in agricultural landscapes, is still limited. In a controlled feeding experiment, we recorded the seed intake and germination success after complete digestion by the European brown hare (Lepus europaeus) and explored its mobile link potential as an endozoochoric seed disperser. Utilizing a suite of common, rare, and potentially invasive plant species, we disentangled the effects of seed morphological traits on germination success while controlling for phylogenetic relatedness. Further, we measured the landscape connectivity via hares in two contrasting agricultural landscapes (simple: few natural and semi-natural structures, large fields; complex: high amount of natural and semi-natural structures, small fields) using GPS-based movement data. With 34,710 seeds of 44 plant species fed, one of 200 seeds (0.51%) with seedlings of 33 species germinated from feces. Germination after complete digestion was positively related to denser seeds with comparatively small surface area and a relatively slender and elongated shape, suggesting that, for hares, the most critical seed characteristics for successful endozoochorous seed dispersal minimize exposure of the seed to the stomach and the associated digestive system. Furthermore, we could show that a hare's retention time is long enough to interconnect different habitats, especially grasslands and fields. Thus, besides other seed dispersal mechanisms, this most likely allows hares to act as effective mobile linkers contributing to ecosystem stability in times of agricultural intensification, not only in complex but also in simple landscapes.

Systematic treatment of morphological fruit types in plants of the class Liliopsida of the flora of Ukraine

In this review, the scope of morphological diversity of fruits within the class Liliopsida belonging to the flora of Ukraine compared to the world flora diversity was analyzed. For the first time, the taxonomic diversity of monocot plants of the flora of Ukraine was analyzed, which includes 235 genera and about 1050 species, and the distribution of fruit types in the largest monocot families revealed. It was found that among monocot plants of the world flora, as also of the Ukrainian flora, more than 70% of generic and species diversity is taken up by the Orchidaceae, Poaceae, and Cyperaceae families having dry uniform fruits: inferior capsule (Orchidaceae) and one-seeded enveloped fruit (Poaceae and Cyperaceae). An annotated list of morphological fruit types was compiled for all 38 families of the natural and cultural flora of monocot plants of Ukraine. Among 12 families of the subclass Alismatidae, apocarpous polymerous or trimerous fruits, mostly with one-seeded fruitlets, occur in six families (Alismataceae, Butomaceae, Potamogetonaceae, Ruppiaceae, Scheuchzeriaceae, Zannichelliaceae). In 12 of 16 families of the subclass Liliidae, trimerous capsules are the most common (Agapanthaceae, Agavaceae, Alliaceae, Amaryllidaceae, Asphodelaceae, Colchicaceae, Hemerocallidacae, Hyacinthaceae, Iridaceae, Liliасеае, Melanthiaceae, Orchidaceae), while in six families berry-like fruit occurs in all members or in the single genus (Asparagaceae, Ruscaceae, Dioscoreaceae, Melanthiaceae (Paris), Liliасеае (Streptopus), Smilacaceae). Among 10 families of the subclass Commelinidae, in four families superior dry one-seeded fruits occur (Cyperaceae, Poaceae, Sparganiaceae, Typhaceae), while another four families have trimerous capsules (Cannaceae, Commelinaceae, Juncaceae, Pontederiaceae). In general, the most typical fruit on the familial taxonomical level is the capsule (17 families), berries occur in 10 families, aggregate fruits and one-seeded fruits are represented each in seven families, while the rarest fruit type is the schizocarp (Juncaginaceae). No monomerous follicles, poricide and operculate capsules, winged fruits and loments were found. The most controversial fruit types are found in two groups of families, for both of them the problem is the gynoecium type. These are families with one-seeded fruit (Аrасеае (Lemna), Cyperaceae, Hydrocharitaceae (Najas), Poaceae, Sparganiaceae, Typhaceae, Zosteraceae) and families with initial carpel fusion (Hydrocharitaceae (Stratiotes), Juncaginaceae, Melanthiaceae (Veratrum), Scheuchzeriaceae, Tofieldiaceae). As a result of our work, the key and the most relevant areas of carpological studies in Ukraine were defined, particularly, unifying the terminology, examination of the anatomical structure of the pericarp, revealing of the evolutionary and ecological aspects of fruit morphology.