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Theavailability of seeds of native species in many countries for grassland restoration is limited; therefore, ex situ seed banks can gain importance as a source of germplasm in the future. We tested the usability of seed accessions of the Pannon Seed Bank for reintroduction with the aim to restore sandy grassland in Hungary. Seeds of 10 native sandy grassland species were seeded in the year of collection and after one or two years of storage. The establishment was estimated by counting seedlings along seeded transects for two vegetation seasons. This study produced the first numerical estimate we know about of native sand grassland species emergence in the field. A low establishment of the tested species was found, ranging from 0.002 to 8%. Within this range, Dianthus serotinus had the highest establishment, while Festuca vaginata, which was sown as matrix species, performed only medium establishment. The short‐term storage (1 or 2 years) of seeds had no significant effect, except for F. vaginata, where seed storage had a positive effect on reintroduction success. The year of seeding had the highest influence on recruitment. Four species were found to emerge over two years instead of only the first year. Based on our results, the weak seed yield of certain years and the low supply of native seeds in the market can be mitigated by using stored seeds. It is recommended to use multi‐year, scheduled seeding to reduce the negative impacts of particularly dry years and to increase the restoration success. [ABSTRACT FROM AUTHOR]

It is known since the 1990s that smoke from burning plant biomass can enhance seed germination or seedling growth for numerous plant species. However, our understanding of the effect of plant-derived smoke on the sprouting of asexual reproductive organs is insufficient. In a laboratory experiment, we tested the hypothesis if smoke treatment (applied as aqueous smoke solution, i.e. smoke-water) enhances sprouting of the asexual reproductive organ for three herbaceous perennial plant species: Convallaria majalis L., Poa bulbosa L. and Ranunculus ficaria L. The smoke treated plant organ was rhizome (C. majalis), bulbous shout base (P. bulbosa) or tuberous root (R. ficaria). We recorded first shoot length, first leaf diameter and number of leaves for R. ficaria, shoot length for C. majalis, and rate and speed of sprouting for P. bulbosa. For none of the species and recorded variables had the smoke treatment significant difference compared to control (moistened with tap water). However, the smoke treated P. bulbosa's survival was significantly higher, and a higher number of C. majalis individuals compared to control remained alive until the end of the experiment. Thus, our results do not support the hypothesis on the positive effect of plant-derived smoke on the sprouting of asexual reproductive organs. However, the beneficial smoke effect on the survival was shown. h is latter result opens an opportunity to use smoke technology in a new aspect: in ex situ conservation programs using propagation from asexual reproductive organs, greater efficiency can be achieved with smoke treatment. Nevertheless, these results are far insufficient to draw a general conclusion on the issue. Further studies are needed involving a much larger number of plant species and various smoke treatments (e.g. aerosol smoke or different dilutions of smoke-water). [ABSTRACT FROM AUTHOR]

Abstract: Transient and steady state responses of leaf gas exchange (photosynthesis (A) and stomatal conductance to water vapor (g s)) to marked changes in photosynthetic photon flux density (PPFD) were studied for two invasive [Cynodon dactylon (L.) Pers. and Sorghum halepense (L.) Pers.] and two non-invasive, native [Bothriochloa ischaemum (L.) Keng and Chrysopogon gryllus (Torn.) Trin.] perennial C4 grass species from semiarid temperate grasslands or croplands. Following an abrupt drop in PPFD from 1300 to 270μmol photon m−2 s−1, the two invasive species reduced g s to a greater extent than A, resulting in higher intrinsic photosynthetic water use efficiency (PWUE= A/g s) at low, compared to high-light conditions. For non-invasives, a comparable drop in g s and A led to invariant PWUE, which was lower than that for the invasive group under low light. The duration and speed of stomatal closure was similar for the four species. However, unlike the other grasses, the noxious weed S. halepense exhibited a negligible net loss in PWUE during the high-to-low light transition. Responses of the native B. ischaemum were mostly intermediate between those of the two invasive species and the non-invasive C. gryllus, which is in agreement with the species’ ecological intermediacy: non-invasive but often reaches local dominance following a disturbance. With a sudden reverse change in PPFD photosynthetic light induction was not faster for invasives than for non-invasives. These results indicate more efficient water use under variable light for invasive compared to non-invasive perennial C4 grasses which may contribute to their success in semiarid temperate habitats with a heterogeneous light regime. Yet, rapid photosynthetic light induction appears to be of less importance in such environments. [Copyright &y& Elsevier]