Sulla Terminologia dei Processi Apomittici

Summary

The Author observing the great disagreement of the terminology usually adopted for the apomictic phenomena, examines the whole series of the phenomena noted both in regards of the formation of the gametophyte and of the embryo. The forming of the gametophyte is fixed on the base of nature of its original cell, normally a haploid spore or »haplospore« (phenomenon of the »haplospory« following the regular meiosis), rarely a diploid spore or »diplospore« (phenomenon of the »diplospory« following the irregular meiosis, as for instance in the case of restitution nucleus, etc.). The original cell can be at least represented by the same cell that usually is the spore mother cell, whether for the outward causes, or for inward causes is lacking the usual reductional process. For the failure of the meiotic process, such a cell cannot be called »spore«.

A cell of the somatic tissue of the sporophyte can even become the original cell of the gametophyte always in case of the absence of the meiosis. These two last cases of apospory are respectively called: »somatic apospory« and »gonial apospory« (= germinal apospory) (Chiarugi 1926).

The formation of the embryo is fixed on the base of the nature of the fecundation. The principal phenomena of the fecundation are represented by the following cases: »amphigamy« (or eugamy, or gamy), »semigamy, »pseudogamy«, »apogamy« »parthenogenesis«. The A. uses the term »apogamy« both for the diploid eggs and for the haploid eggs in which the stimulation of the division is produced by the pollen-tube or by male nuclei, in absence of the gamy.

The term »parthenogenesis« is restricted to the division of the haploid or diploid eggs in which the stimulation is not caused by pollen-tube nor even for the great reason, by the male nuclei existing in it.     

Insediamento e Diffusione di Buddleia Davidii Franch

Abstract

«Buddleya davidii» in «Valtellina» (North Italy), its settling and diffusion. — Vegetational areas where «Buddleya davidii» is naturalised in Valtellina are described and the subsequent phases are followed through 18 years.     

Sulla Presenza di Ificellarioli e di Conidi in Mieobionti Lichenici Coltivati in « Vitro ». Riassunto

Abstract

On the presence of « hyphycellariola » (swollen celles) and conidia in three lichenized fungi cultivated « in vitro ». — The Authors refer to the presence of « cellariola » (and « hyphycellariola ») found in pure cultures « in vitro » of the mycobiont of Xanthoria parietina and describe the morphology of conidia in the fungus isolated from Sarcogyne similis and Acarospora fuscata.

As far as the « cellariola » and « hyphycellariola » are concerned, it is the first note relative to the mycobionts of Lichens.

The Authors report the data of the utilized medium and the morphological observations.

This previous studies will be intensified by further research.     

Phagnalon Metlesicsii Nova Sp. Aus Westsizilien,Mit Einem Überblick Über Die Gruppe Von Phagnalon Rupestre Im Mittelmeerraum

Abstract

«Phagnalon metlesicsii», a new species from Western Sicily, with a survey of the «Ph. rupestre» — group in the Mediterranean Region. — Phagnalon metlesicsii, a new species of the complex Ph. rupestre — Ph. graecum, is described. It is entirely glabrous and occurs in Western Sicily (M. Cofano) on vertical limestone rocks, nearly 200 mts. above the sea, in community with a flora particularly rich on endemics. The variability of the whole complex is discussed and some infraspecific taxa are proposed.     

Fenomeni citologici nuovi nella embriogenesi (“semigamia„) e nella microsporogenesi (“doppio nucleo di restituzione„) di rudbeckia laciniata L.

Abstract

L' A. descrive in Rudbeckia laciniata L. una specie apomittica, con gametofito femminile diploide originato da quattro divisioni del nucleo della cellula madre; di cui la prima di tipo restituzionale.

Descrive il fenomeno della «semigamia», per cui lo spermio penetra nella cellula uovo diploide senza degenerare e senza fondersi col nucleo femminile, ma si divide insieme a questo per originare un embrione di tipo chimerico.

Analogo comportamento presenta R. speciosa Wender.

Descrive anche la formazione di granuli pollinici giganti, tetraploidi, originati dalla formazione di un nucleo di restituzione in seguito ad ognuna delle due divisioni meiotiche («doppio nucleo di restituzione» o «nucleo di birestituzione»).     

The cryptopolyploidy (Jaretzky 1928: «verkappte Polyploidie»; Chiarugi 1933: «criptopoliploidia»; Melinossi 1935, 1937: «duplicazione endocromosomica»). A terminological criticism.

Abstract

In the cytological literature and text-books, the term cryptopolyploidy is mainly ignored and sometimes re-interpreted and often wrongly quoted from the point of view of historical accuracy. The paternity over this term should be ascribed to Chiarugi (1933), although Jaretzky (1928a, b), while investigating karyologically two species of the genus Bunias, B. orientalis and B. erucago, first advanced a concept of «verkappte Polyploidie» to indicate the occurrence of chromosomes of enlarged size hypothetically due to fusion of homologous members (Jaretzky's «Sammelchromosomen»). By such homologous chromosome fusion a polyploid karyotype could appear as a diploid karyotype. A pupil of Chiarugi, Roma Melinossi, reinvestigating the two species quoted by Jaretzky, Bunias orientalis and B. erucago, documented a quite different karyological state for these species, cf. Melinossi (1935, 1937), that is the presence of the same karyotype (2n=14) in both species and the occurrence of chromosome of doubled size in B. erucago. Melinossi recognized B. erucago to be the cryptopolyploid species (obviously crypto-tetraploid) and not B. orientalis as assumed by Jaretzky and reinterpreted the chromosomes of doubled size as the result of a «duplicazione endocromosomica» (MELINOSSI, 1937).

Almost contemporaneously a second pupil of Chiarugi, Fernanda Pannocchia-Laj, in a karyo-embryological investigation of some species of the genus Vinca, described the occurrence of another case of cryptopolyploidy (sense Melinossi, that is by «duplicazione endocromosomica»). Besides the minor fact that this latter author spelled the term «criptopoliploidia» also as «criptopoliploidismo», her paper is very remarkable because suggested the probable occurrence of a degree of cryptopolyploidy higher than that of Bunias (crypto-tetraploid), namely the occurrence of «… una entità criptopoliploide con valore superiore al tetraploide, probabilmente ottoploide» (cf. PANNOCCHIA-LAJ, 1938 p. 177, p. 178, Fig. 36: criptottoploide).

On the basis of the results of a comparative karyological study between Vinca minor, V. major and V. difformis, PANNOCCHIA-LAJ ascribed to V. minor the diploid karyotype «2n=46», to V. major the tetraploid karyotype «2n=92», and to V. difformis the cryptopolyploid karyotype «2n=46 (x4?)». Since PANNOCCHIA-LAJ (1938, pp. 184–185), following MELINOSSI (1937), interpreted the origin of cryptopolyploidy as a phenomenon due to «duplicazione endocromosomica», the formula «2n=46 (x4?)» clearly means occurrence of «doppia duplicazione endocromosomica» or «quadruplicazione cromosomica».

The author is personally aware that PANNOCCHIA-LAJ intentionally, for scientific prudence, avoided to include such a terms in her account.

The papers of CHIARUGI, MELINOSSI and PANNOCCHIA-LAJ have been largely ignored by the subsequent cytological literature and the term cryptopolyploidy has been variably quoted or interpreted and also reinvented (cf. HOLT in SPARROW & NAUMAN, 1974)!

From a terminological point of view, there are two sound considerations which suggest a refusal of the term cryptopolyploidy, namely:

- the prefix crypto does not qualify, it only means that such a polyploidy is «not visible» (hidden) by the methods of the observer;

- the choice of the prefix crypto is injustifiable because, the cases of cryptopolyploidy show the general morphology of the relative known polyploid species, that is they are phenotypically polyploids!

Both considerations, together, suggest the refusal of the prefix crypto and the proposal of the neoterm phenopolyploidy (phenotypic polyploidy). Necessarily, the indication of phenopolyploidy is nothing else but a provisional term waiting for a modern reinvestigation of both the crypto-tetraploid Bunias erucago and the crypto-octoploid Vinca difformis.     

Saxifraga Berica (Béguinot) D. A. Webb E Asplenium Lepidum Presl Sui Colli Berici

Abstract

«Saxifraga berica» (Béguinot) D. A. Webb and «Asplenium lepidum» Presl on the «Colli Berici». – We have identified a new association in the small caverns of the calcareous rocks in the hills of the north-eastern zone of the «Colli Berici», rising from the Italian plain near Vicenza. We have adopted for this association the name: ADIANTO-SAXIFRAGETUM BERICAE. This phytocoenose is characterized by the endemic «Saxifraga berica». We have found new stations of this remarkable plant and reported some features of this species to complete the diagnosis of D. A. Webb. In two station of this association we have found also the rare «Asplenium lepidum», new for this region.     

La Vegetazione e L'ecologia Di Pratofiorito (Appennino Settentrionale)

Abstract

Ecology and vegetazion of mount Pratofiorito. — The author examines position, climatic conditions, geological nature and vegetation of Mount « Pratofiorito » in the Tuscan Appennine.

Mount Pratofiorito is a residue of secondary rocks and derived soil surrounded by tertiary and quaternary rocks and soil.

Its vegetations is actually constituted by grass-land and so it differs-from that of the neihbouring mountains which comprises the flora has been made. This list was then comparend with spades found in the adjacent beech and helm-oak zones.

From these comparisons one can deduce thath the meadow of « Graminaceae » and « Cyperaceae » growing on Mount Pratofiorito may bed considered as a grass-land resulting from the degradation of an arboreal zone, problably from a beech-wood.     

Ricerche Sulla Vegetazione Dell'etruria Marittima

Summary

The dates of foundation of the oldest university botanical gardens.

The dates of foundation of the oldest Botanical Gardens in Italy are not well known to the greatest part of the students of Botanical History.

Also today Ms. A. Guillaumin in his « Histoire de la Botanique en France (Paris, 1954) pag. 188» writes it was « Serenissima Repubblica Veneta » who founded the first Botanical Garden in 1533, whilst in that year only the chair of Bonafede had been constituded and the foundation of the Botanical Garden in Padoa happened later in 1545.

Really the most ancient Botanical Garden in the world is not that of Padoa, but that of Pisa.

Recently in the « Archivio di Stato » of Florence has been discovered by Fedeli a letter dated July 4 th 1545 written by Luca Ghini. From it it is clear that already a month before that date Luca Ghini was collecting plants to be coultivated in the academic garden of Pisa « for utility of students ».

The critical analysis of many papers by Luigi Anguillara allowe us to establish that Luca Ghini with the same Anguillara collected plants in the surreoundings of Pisa and on the Apuane Alps, from 1543 to 1544, and planted them in the academic garden of Pisa, which therefore must be considered the first Botanical Garden in the world, founded in the Summer 1543.

The second Botanical Garden in order of time is that of Padoa having been established by the « Senato Veneto » in 1545 and actually founded on July 7 th 1545 (de Visiani). The first director of Botanical Garden of Padoa was Luigi Anguillara after having left Pisa where he cooperated with Luca Ghini to found the Botanical Garden of Pisa.

Finally the third Botanical Garden is that of Florence (« Giardino dei Semplici ») founded as a dependance of that of Pisa by Luca Ghini, for school utility during the holyday, when the Florentine students remained at home. The date of its founding is December 1st 1545, as it appears from an an attorney document dated November 16th 1545 preserved in the « Archivio di Stato » of Florence (Volpi).

In conclusion the right chronology of the oldest University Botanical Gardens in the world is as follows:

1st: Pisa, Summer 1543

2nd: Padoa, July 7th 1545

3rd: Florence, December 1st 1545.     

“Eumeiosi” e “Meiosi Apoomeotipica” Seguita da “Mitosi a Diplounivalenti” Nel Tessuto Somatico di Sambucus

Summary

The Authors describe in Sambucus nigra L the occurrence of the » apohomeotypic teiosis « followed by a »mitosis with diplounivalents « (Battaglia 1945, 1947) in ae somatic tissue of the style. The AA. observed also the occasional formation f four haploid nuclei and then the occurence of the »eumeiosis« (Battaglia 1945).     

Fissazione di C14O2 in Colture di Tessuti Vegetali « in Vitro »

Abstract

C¹⁴O₂ fixation in plant tissues « in vitro ». — In the present work it has been examinated the autotrophic and heterotrophic CO₂ fixation of explants of « Helianthus tuberosus » « in vitro » and the photosyntetic efficiency of leaves produced from buds of « in vitro » explants of « Cichorium intybus » compared with that of mature leaves from normal plants of the same species. From our results it is evident that « in vitro » explants of « Helianthus tuberosus », grown, in the light, are able to autotrophically incorporate C¹⁴O₂; the distribution of the radioactivity into the various fractions shows a large influence of the light on the neutral fraction containing sugars (50% of the total radioactivity). In the chlorophyllous explants the dark CO₂ fixation is obviously of heterotrophic type: 97% of the total radioactivity is incorporated in amine acids (43%) and the organic acids (53%); on the other hand in the dark grown explants the radioactivity is differently distributed between amino acids (59%) and organic acids (39%). Mature leaves from normal plants and leaves produced from buds of « in vitro » explants of « Cichorium intybus » incorporate the same quantity of C¹⁴O₂ when expressed per mg of chlorophyll; the different distribution of the radioactivity in the neutral and acid fractions could be explained in terms of a different utilization pathway of the photosynthates in the two tissues.     

Stipa Trichotoma Nees nella selva di San Rossore,nuovo inquilino della flora toscaista

Summary

The Author discovers and describes a new station of Stipa trichotoma Ness (Nassella trichotoma Hackel) in the «Selva di S. Rossore » (Pisa), where it represents an adventitious and probably newly naturalized species for the Tuscan Flora.

The Author refers on the preceedind foundings of this south-American plant in Italy, discussing the complicated sinonimy, and points out the opportunity for the constitution of-a new section Nassellopsis and the interest to include the species in the new edition of «Nuova Flora Analitica d'ltalia» of Adriano Fiori.     

Contributo alla Conoscenza dell'idratazione e della Pressione Osmotica Nelle Specie di Tre Associazioni Forestali delle Marche: I° - L'idratazione

Abstract

Researches on the water content and osmotic pressure in plants of three forest associations in the Marche. I° - The water content. — The main forest associations of the Umbro-Marchigiani Appennines are the Orneto-Quercetum ilicis, the Quercetum pubescentis (s. l.) and the Fagetum. In each of these associations a typical station has been chosen where the most important species have been followed from March to November 1963 in order to determine the seasonal variations of their water content (« T.I. »)expressed as percentage of fresh weight.

The annual curves show that the water content reaches very high levels in the early stages of plant development while it falls to lower levels later in the season when the leaves are full grown. The water content of each species follows a different course and can be considered a specific character. Taking into account the maximum and minimum levels of water content of the three groups of species a « hydric spectrum » has been worked out for the three associations.

The water content of each species has also been calculated as percentage of dry weight (imbibition percentage: « G.I. »).     

Nuovi Dati Sulla Distribuzione Di Isoétes Malinvernianum in Lomellina

Abstract

New data on the distribution of « Isoëtes malinvernianum » in Lomellina. — The Author relates the discovery of many new stations of Isoëtes malinvernianum in Lomellina (Province of Pavia). Many observations carried out in these new localities and in the most part of the already recorded localities near Novara and Vercelli have allowed him to modify some convincements on the habitat of this well known endemism. So he reports that Isoëtes malinvernianum vegetates not only in the waters of « fontanile » but also in waters of the most different sources, that this species is not solitary but accompanied by many species as Callitriche palustris, Fontinalis antipyretica, Sagittaria sagittifolia, Vallisneria spiralis, Potamogeton crispa and few other species more. Isoëtes malinvernianum, besides, is not damaged by dredge works in the canals and is present not only in morainic soils and in the diluvial soils transformated in ferreto but also in the terraced flood named with old terms as « Terrazziano » or « Diluvium recente » and in the diluvial soils of the « Alluvium ». Now at least it is not possible to ascribe plant communities of which Isoëtes malinvernianum makes part to a well defined association.     

Ricerche Sulla Vegetazione dei Dintorni di Firenze

Summary

It is related on some phytocenoses of the southerly Florence hills, lying on the boundary of the two basal biochores of peninsular vegetation. Although the proximity and the chorographical analogy at the south-westerly ones and at Ceceri Mount, which are included yet in the » Quercetum Ilicis « ambit, these hills are whereas sensible displaced in the » Quercetum pubescentis «. They have microtherme elements of higher planes, but they have in yet the marks of littoral biochore, for instance Smilax aspera, abundantly penetrating in hedges and in a pine-grove but non in coppices of Quercus Cerris.     

Microbiocenosi fotosintetiche delle Terme « Selinuntine » di Sciacca (Sicilia)

Abstract

Photosynthetic microbiocenose of the « Selinuntine » Hot Springs in Sciacca, Sicily. - Cyanobacteria belonging to the genus Oscillatoria, typical of thiobiotic habitats, were predominant in the photosynthetic microbiocenose of the « Selinuntine » Hot Springs in Sciacca. Oscillatoria animalis was prevalent in the thermal microbial community having the highest temperature and sulfide values suggesting a particular physiology requiring the presence of low redox compounds for its growth. Anoxigenic photosynthetic bacteria constitued a minor component of the biocenose.     

Primi Dati Sulle Alghe Della Scogliera « I Travi » di Portonovo (Ancona)

Abstract

First data on the seaweeds of the reef « I Travi » of Portonovo (Ancona). — The reef « I Travi » is formed by a series of nearly vertical rock strata which from Mount « I Corvi » dip into the sea with a general direction WNW-ESE. The rock face looking towards the open sea (that is roughly to the North) is exposed to the action of the waves. The sea is particulary rough when the wind blows from the North (« Bora »), and the East (« Levante »).

The temperature of the water throughout the year varies from 9.5[ddot] C in February to 27 [ddot]C in September, that is over a range of 17.5 [ddot]C. In June the salinity of the water was of 33.6%, and the pH had a value of 8.1. Ascending and descending currents and water movements seem to mix efficiently the upper and lower waters.

The seaweed population of the rock face varies longitudinally. In the Wetsern part Acetabularia is dominant; there is a central part with prevalence of Cystoseira, and an eastern part with prevalence of Ceramium and Cladophora. Vertically one can distinguish: a Littoral Zone of 40–45 cm (maximum amplitude of the tides) with Cladophora, Enteromorpha, and other Chlorophyceae; an Infralittoral Zone with predominance of Cystoseira, Gracilaria, and, lower down of various Rhodophyceae. The Eulittoral Zone is missing.     

Ultrastructural characteristics of « Diplotaxis erucoides (L.) DC. » suspensor

Abstract

The development and general morphology of Diplotaxis erucoides (L.) DC. suspensor is of the « Onagrad Type », « Alyssum Variation ». Maximum growth of the suspensor occurs from the globular to the early heart stage of embryo development. The suspensor starts then to degenerate disintegrating shortly after the torpedo stage of the embryo.

The wall ingrowths of the long, tapering, basal cell are especially abundant at the cell's micropilar pole which is closely surrounded by well developed wall ingrowths formed by the endosperm. Wall ingrowths and plasmodesmata are present on the suspensor cells cross walls with the exception of the cell closest to the embryo. No such structures in fact are present on the walls separating this last cell both from the embryo and from the rest of the suspensor. Wall ingrowths are generally associated with numerous, large, mitochondria.

The morphological data seem to indicate that absorption and transport of nutrients from the surrounding tissues is a main function of the suspensor. The possibility of an elaborative and secretory function of this structure is discussed.