Proliferazione e Rizogenesi in Frammenti Fogliari di Cichorium Intybus L.: Osservazioni Istologiche

Abstract

Proliferation and formation of roots in leaf fragments of «Cichorium intybus» L.: histological observations. — Leaf fragments of Cichorium intybus grown in vitro, from radical stocks, are cultivated in aseptic media. They are taken from different leaf areas and planted into the substratum with their distal or proximal part, or else put down horizontally on it. The frequency of proliferation is influenced only by the position of the fragments in relation to the substratum. Histological variations connected with the arising and the development of callus and roots are studied. The proliferation of the callus as well as the formation of roots by the leaf fragments take place in the area of the veins; the callus, in its turn, may give rise to other callus or roots. The callus obtained consist either of more or less homogeneous parenchima with vascular nodules, or of untidy masses of tracheids, parenchimal cells and little dividing cells. The roots have a structure similar to that of roots directly cultivated in vitro from radical stocks of chicory and to that of the roots in the natural state.     

Flora e Vegetazione Dell'Isola Di Pianosa (Isole Tremiti)

Abstract

Flora and vegetation of the Isle of Pianosa (Isles Tremiti). – The flora and vegetation of the Isle of Pianosa are here described. The flora is composed of common mediterranean species with some adriatic endemics. The vegetation has a halophilous-nitrophilous character. The plant formations identified on this isle are shown in the map (fig. 1).     

L'Evoluzione Dei Cloroplasti Durante L'Inverdimento Sperimentale Di Frammenti di Tuberi di Topinambour (Helianthus Tuberosus)

Abstract

Lembotropis emeriflorus (Rchb.) Skali?ka in the Carnian Alps too.—Lembotropis (=Cytisus) emeriflorus, endemic species between the lakes of Lugano and Como, occurs also in the Southern Carnian Alps, where it grows either on gravelly habitats or on rocky slopes or under Austrian pine woods of the mountain zone. After this discovery its distributional pattern is now a typical bicentric one.     

Flora Delle Isole Palmaria e Tino (Golfo Della Spezia)

Abstract

Flora of Palmaria and Tino islands. — Palmaria and Tino are two small islands at the entrance of the Gulf of La Spezia. They are formed of grey fossiliferous limestones of the Rhaetian period and of more recent — but still of the Rhaetian period — dolomitic limestones. Their climate is definitely more mediterranean than that of the La Spezia coasts laying near by; the winters are milder and the annual precipitations much lower (at the Palmaria 525 mm, at La Spezia 1375 mm. The flora is composed of 399 entities and has a biological spectrum in which the Hemicryptophytes predominate (35,33%), however also the Therophytes (29,57%) and the Geophytes (15,03%) are frequent. The test of the floristic composition shows that the eumediterranean elements are predominant (24,56%) but also the submediterranean (12,53%) and the central southern European (13,53%) are frequent; besides, the subatlantic (6,01%) and the Eurasian ones are also to be found (9,27%). From the test of the floristic components of the three floras of Palmaria and Tino, Capo Caccia in north western Sardinia and of the Marettimo island in western Sicily, it has been found that there is a bigger quantity of eumediterranean elements than in the islands near La Spezia (24,56%) at Capo Caccia (42,14%) and at Marettimo (47,60%), and on the contrary a decrease of the central southern European (13,53%, 9,50%, 6,40%). The fact that the island of Sardinia was separated from the continent since very early times is proved by the presence at Capo Caccia of a lower number of euro-centralasiatic plants (6,76%, 3,30%, 6,60% respectively), of sub-Atlantic ones (6,01%, 1,65%, 3,80%), and of Eurasian ones (9,27%, 7,85%, 8,20%) and on the contrary by a higher number of Sardinian-Corsican endemisms at Capo Caccia (8,67%), definitely higher than the ones in Sicily at Marettimo (3,40%) and the Tuscan-Ligurian endemisms at Palmaria and Tino (only 0,75%) islands which are a few dozen meters near the coast, from which they were separated in recent periods. Among the plants of phytogeographycal interest I would like to mention Centaurea cineraria which is present at the Palmaria and Tino with the var. veneris; may be once spread on most of the Mediterranean coasts. Most of the Mediterranean plants growing on the Palmaria and Tino have a distribution area which includes a great part of the Mediterranean. Just a few of them (Cephalaria leucantha, Argyrolobium zanonii, Phagnalon sordidum, Staehelina dubia, Pinus pinaster, Antirrhinum latifolium) are western submediterranean, distributed mostly in Europe; in comparison, at Marettimo there are western eumediterranean plants growing in northern Africa with some remains in the Spanish peninsula. At Marettimo eastern eumediterranean plants also grow, while at Palmaria and Tino are to be found only some plants that, from the north-eastern coasts of the Mediterranean sea, reach the interior of the Balkan peninsula (Genista januensis) or the Pontic region. (Coronilla cretica, Dorycnium pentaphyllum var. berbaceum).     

Frammenti cotiledonari di Aesculus hippocastanum L. coltivati in vitro. Primi dati sul comportamento dell'amido e dell'escina

Abstract

Fragments of Aesculus hippocastanum L. cotyledons grown in vitro. First results about starch and aescin characteristic features.—Cotyledon fragments of Aesculus hippocastanum grown in vitro in different media have been able to form callus and roots. The starch granules in the new cells are compound in structure and morphologically different from the simple cotyledon granules, whereas they are similar to the granules of the other parts of the plant in toto. Moreover, the callus has no aescin even though it originates from the cotyledor tissues.     

Osservazioni Sull'embriologia di Nerine Rosea e di Amaryllis Belladonna (Amaryllidaceae)

Summary

The embryosac development in Nerine rosea Herb. has been found to occur according to the Normal type and indications of an identical development were found for Nerine curvifolia Herb., contrary to the observations of Schlimbach (1924), who reported a Lilium type for this species. Embryosacs of the Normal type also occur in Amaryllis Belladonna, to which a tetrasporic development had been erroneously ascribed by Schlimbach (1924). In Nerine rosea Herb. the formation of the microspores is of the «successive» type; the aploid cromosome number is n=12, in accordance with the describtions of Heitz.     

Flora Delle Argille e Dei Tufi di Civita di Bagnoregio (Alto Lazio)

Abstract

Flora of the clays and the tuffs of Civita di Bagnoregio (Upper Latium). — This work is the result of floristic research developed from 1968 to 1970 on tuffs and mainly on the clays of Civita di Bagnorcgio. After having summarily described the geo-ecological conditions, the author lists in all 489 entities. The biological spectrum of clays shows a high presence of Therophyta and a low percentage of Phanerophyta; on the contrary on the tuffs are present more Phanerophyta and less Therophyta; on the whole the flora is marked from the Emicryptophyta. Phytogeographical analysis indicates a prevalence of mediterranean elements. The author delineates moreover the most important floristic aspects, refering the frequentest entities and point out the intense anthropization wich has prevented the preservation of the woody formations, today completely away from clayey area.     

Note floristiche e fenologiche nel territorio di Arneo (Fra Taranto e Gallipoli)

Summary

The author describes the vegetation and phenology of a Quercus Ilex wood in the Comprensorio dell'Arneo, betwen Taranto and Gallipoli along the eastern shore of the Ionian Sea (Golfo di Taranto). The wood consists partly of a degraded bushy vegetation.

The wood was visited eleven times during the year and each time species found flowering were noted (Table at pp 296–301): the greatest number of them, many being therothytes, was found on April 21rst (fig. 2) with about a month's delay in comparison with Palestine (Gindel). In May there is a considerable i decrease in number of species flowering. In summer and winter, because of drought and low temperature very few species, mostly geophytes, were found flowering, and only slightly but markedly more in Autum.     

Studio Floristico e Fitogeografico Delle Piccole Isole della Sardegna Nord-Occidentale

Summary

The author has studied the flora of the little islands of Northe-West Sardinia. In a former note he has referred on Isola Piana, in this one he refers on: Isola Rossa, Isola dei Porri, and Isola Foradada.

After having done the census of the species, notifying particularly the dominant ones and after having put in evidence the principal plant communities he kept his attention on some endemic species two of which are probable endemisms new to the science: Olea europaea L. v. latifolia (mihi) and Smilax aspera L. v. inermis (mihi), coming to the conclusion:

1°) The study should confirm the hypothesis that in the little islands may be manteined species, or ancient in regression, or recent in variation the recessive characters of which would be substracted to overcome of the dominant charaters of a largest population;

2°) The florae of the four islands, for theier geographical position are the expression of the Mediterranean half-dry climate;

3°) They present their plant communities from which springs the autonomy of the different «Ecoidi» with theier different predominance established by the equilibrium attained in them.