Corresponding author: Loretta Pace ( loretta.pace@univaq.it ) Academic editor: Simonetta Bagella
© 2020 Loretta Pace, Marika Pellegrini, Giovanna Pannunzio, Gianfranco Pirone.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Pace L, Pellegrini M, Pannunzio G, Pirone G (2020) First report of fasciation symptom in Artemisia eriantha (Asteraceae), a typical orophyte of high-altitude cliffs, in Central Apennines (Italy). Plant Sociology 57(1): 23-28. https://doi.org/10.3897/pls2020571/03
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Artemisia eriantha Ten., also known as "Apennines genepì", is a valuable aromatic plant with several medicinal properties. Among the several phytoplasma symptoms to which this plant can be subjected, the fasciation is one of the less reported and studied. In natural environments this plant is a characteristic species of the association Artemisietum erianthae
Apennines genepì, Artemisietum erianthae, Gran Sasso Monti della Laga National Park, Macrosiphoniella artemisiae, micropropagation, restocking, stem fasciation
Artemisia eriantha Ten. [syn. A. umbelliformis Lam. ssp. eriantha (Ten.) Vallès-Xirau and Brañas (Asteraceae)], known as "Apennines genepì", is a small plant of Central Italy showing 10-15 cm stems, bipinnate or tripinnate leaves, petioles and silvery-white trichomes. In natural environments its flowering period is in summer, and the flowers are yellow and organized in flower heads, arranged along the stem to form a spike (
A. eriantha is also present, sporadically or with low cover values, in other vegetation types of high altitude, for example, in the associations Saxifrago speciosae-Silenetum caenisiae Petriccione 1993, found on Sibillini (
This aromatic plant produces oils with a complex terpenoid profile, rich in sesquiterpenes and several compounds and whose content increases with the plant age (
Like other medicinal and aromatic plants, Apennines genepì can be affected by several symptoms. Among them, fasciation is one of the most interesting phenomena, in fact, it is distinct from other kinds of deformity (
Fasciation is very common in species belonging to several families (e.g. Asteraceae, Rosaceae, Ranunculaceae, Liliaceae, Euphorbiaceae, Crassulaceae, Fabaceae, Onagraceae and Cactaceae –
In the study area, cultivation practices of Apennines genepì have been proposed to restock this endangered species and to offer the local populations the opportunity to promote economic activities in high altitude areas, whilst preserving their local habits and traditions (
In vitro Apennines genepì plantlets and tissue cultures were obtained from seeds collected on Monte Portella 2500 m asl (Gran Sasso Monti della Laga National Park) in August 2013 (Fig.
In spring 2014 about 10.000 clones were obtained by in vitro propagation and at the end of May they were transplanted in two experimental fields located at Barisciano (AQ) and Assergi (AQ) in the Gran Sasso Monti della Laga National Park. The main features of selected sites are detailed in Table
Features of field sites of Artemisia eriantha.
Parameter | Barisciano (AQ) | Assergi (AQ) San Pietro Camarda |
Altitude (m) | 1170 | 1200 |
Geographical coordinates | 42°20'25"N, 13°34'14"E (DMS) | 42°26'30"N, 13°28'19"E (DMS) |
Fertilization | None | None |
Previous cultivation | uncultured | Solanum tuberosum |
Soil pH | 8.35 | 8.35 |
P (g/kg) | 6 | 9 478 |
N | 1.65 | 2.16 |
K | 6 | 9.47 |
At the end of May 2015, the adult plants were mapped and collected; during the samplings twelve fasciated plants were discovered at Assergi experimental field, randomly spread throughout the field. The plants were observed and photographed then were brought in laboratory. After that the width of the stems just below the fasciated heads was measured and the number of flower heads was counted. Two sample T-test was used to evaluate whether there was a significant difference between fasciated and non-fasciated plants with “Past3” software for experimental field of Assergi. Some plants were dried, others were cryopreserved at -80°C and were used for nucleic acid extraction (
Some specimens of nymphs and adults of aphids observed in mid May 2015 at Assergi experimental field, were collected in plastic bags and brought to the laboratory. According to the current preparation method for aphids (
A. eriantha specimens did not show any abnormality during micropropagation process. Although transplanted clones exhibited a high morphological plasticity, with different sizes of rosette and various number of shoots, they were morphologically identical in the two experimental fields (p > 0.05). In 2015 spring, the flowering was exceptionally abundant up to 16 flower-heads for rosette (Fig.
Except for mineral contents, soil analysis did not show differences between the two experimental fields. The highest mineral content was recorded for Assergi field and was due to the previous cultivation with Solanum tuberosum L. (Table
In Table
Biometrical parameters recorded for fasciated and normal plants of Artemisia eriantha (mean±SD).
Sample | Flower heads | Width of stems |
Fasciated plants | 23.58 ± 7.29 | 7.74 ± 6.54 |
Normal plants | 16.74 ± 5.26 | 1.15 ± 0.254 |
T-test | t = 4.40; p < 0.001 | t = 22; p < 0.001 |
The nested PCR tests carried out on nucleic acid extracted from symptomatic materials provided negative results for phytoplasma presence.
The occurrence of aphids was observed only on upper parts of Apennines genepì of Assergi experimental field. The infestation was observed especially between inflorescences, and both adults and nymphs were found (Fig.
As stated before, the biotic factors can have an inducing ability on fasciation arising (
Fasciation was noted only in the field of Assergi. Both the fields were transplanted with plantlets derived from clones obtained from several seeds. Thus, this phenomenon could result also from micropropagation process. Multiplication of plants by this technique, can induce phenotypic aberrations in ex vitro cultivations that were not observed during in vitro culturing (
Although micropropagation process can be a valid tool for the recovery of plants threatened by climatic change and undiscerning collection, this technique might induce phenotypic aberrations in ex vitro cultivations and should be for this reason used with great care. This process, together with the presence of other biotic and abiotic factors, could have induced plant fasciation in Artemisia eriantha. The presence of the aphid Macrosiphoniella artemisiae on Apennines genepì is here described for the first time and shows that careful control of aphids’ infestation, by appropriate field management strategies, is important to protect the restocking of this aromatic plant.
We wish to express our sincere appreciation to Prof. Sebastiano Barbagallo for identifying the aphid samples and to Prof. Assunta Bertaccini and Dr. Samanta Paltrinieri for phytoplasma testing.
All authors contributed equally to this work. The authors have no funding to report. The authors have declared that no competing interests exist.