Giuseppe Fabrini

Are Red Lists really useful for plant conservation? The New Red List of the Italian Flora in the perspective of national conservation policies

“The New Red List of the Italian Flora” includes all the Italian policy species and other species of known conservation concerns for a total of 400 taxa, 65% of which are threatened with extinction. The Red List is based on a huge georeferenced data-set useful for conservation purposes.

Growth pattern of Bidens cernua L.: relationships between relative growth rate and its physiological and morphological components

Seedlings of Bidens cernua L. emerged when mean air temperature was 17.0±1.3 °C. The highest net photosynthetic rate (PN), 13.8±0.8 µmol(CO2) m−2 s−1, was monitored during the vegetative period (May–August), decreasing on an average by 50 % during flowering (August–September) and during fruiting (September–November) phases. The senescence phase (October–November) was characterised by 79, 58, and 18 % decrease of PN, chlorophyll content, and leaf area (LA), respectively, from the maximum values. The time span from seedling emergence to the end of fruiting phase was 202 d. The total plant biomass was 1.58±0.05 g of which 81 % was aboveground plant portion. The total dry mass relative growth rate averaged over the assimilation period was 0.0804±0.0002 kg kg−1 d−1, and it was correlated to both the net assimilation rate (NAR) and the leaf area ratio (LAR).

Temperature responsiveness of seedlings maximum relative growth rate in three Mediterranean Cistus species

Aims Relative growth rate (RGR) is an indicator of the extent to which a species is using its photosynthates for growth and it is affected by environmental factors, including temperature. Nevertheless, most of plant growth studies have been carried out at a single growth temperature or at different temperature treatments, resulting in the lack of information on the relationship between RGR and changing mean daily air temperature. We analyzed the temporal changes in RGR during early growth stages in three Cistus species grown outdoor in a common garden from seeds of different provenances. Moreover, we wanted to define the relationship between daily changes in RGR and mean daily air temperature for the considered provenances. The hypothesis that intra-specific temporal variations in RGR can reflect differences in the behavior to maximize RGR (RGRmax) in response to temperature was tested. Methods Seedlings of C. salvifolius, C. monspeliensis and C. creticus subsp. eriocephalus were grown outdoor in the experimental garden of the Sapienza University of Rome under a Mediterranean climate. We analyzed early growth with non-linear growth models and calculated function-derived RGRs as the derivative with respect to time of the parameterized functions used to predict height divided by current height. The relationships between function-derived RGRs and mean daily air temperature were analyzed by linear and non-linear models, which were ranked according to their standard errors and correlation coefficients. The temperature dependency of RGRmax per each provenance was evaluated through the relationship between RGRmax and the coefficients of the best regression model obtained. Important Findings A parameter that could summarize the temperature dependency of RGR up to RGRmax during the early growth stages for the selected provenances was defined. This allowed us to highlight that a greater RGR temperature responsiveness was related to a delay in the time to reach RGRmax independently by the species. Nevertheless, a greater temperature sensitivity of RGR lead to a reduced maximum height which reflects a negative trade-off between the length of the developmental phases and the extent of RGR temperature responsiveness. Thus, variations in temperature responsiveness of RGR up to RGRmax have a significant role in shaping the early growth for the investigated species. Our findings quantitatively define provenance dependent strategies by which the selected species cope with daily air temperature variations during early growth.

Growth analysis of a reestablished population versus a natural population of Bidens cernua L.

Abstract A reintroduction experiment of Bidens cernua L., a species included in the Red List of Italian Flora, was carried out at Lake Posta Fibreno (Lazio, central Italy). There were no significant differences in the length of the phenological phases between the reestablished population (Pr) and the natural one (Pn). The length of the phenological cycle, from seedling emergence to the end of the fruiting phase, was 207 ± 3 days. The relative growth rate in height (RGRH) and relative growth rate in mass (RGRm) were significantly (p < 0.05) higher for Pr (0.047 ± 0.001 cm cm−1 d−1 and 0.057 ± 0.001 g g−1 d−1, respectively) than for Pn (0.045 ± 0.001 cm cm−1 d−1 and 0.055 ± 0.001 g g−1 d−1, respectively). There were significant (p < 0.05) differences for plant height (H) and total leaf area per plant (TLA) between Pr and Pn, the latter having the lower values. Total plant dry mass (PDM) was significantly higher for Pr, and the above‐ground/below‐ground dry mass ratio was 6.7 ± 0.4 and 4.7 ± 0.2 for Pr and Pn, respectively. On the whole, results demonstrate that the Pr of B. cernua has the potential to develop in a manner that is demographically similar to the Pn present in the Posta Fibreno Lake protected area. Abbreviations: H, plant height; LA, mean leaf area; LM, leaf dry mass; PCA, principal component analysis; PDM, total plant dry mass; Pn, natural population; Pr, reestablished population; RGRH, relative growth rate in plant height; RGRm, relative growth rate in plant dry mass; SLA, specific leaf area; TLA, total leaf area per plant

Are Red List really useful for plant conservation? The New Red List of the Italian Flora as a study case in the perspective of national conservation policies

“The New Red List of the Italian Flora” includes all the Italian policy species and other species of known conservation concerns for a total of 400 taxa, 65% of which are threatened with extinction. The Red List is based on a huge georeferenced data-set useful for conservation purposes.