Studio Anatomico-Ecologico del Legno Secondario di Alcune Piante del Fezzan

Riassunto

L'A. studia il tessuto legnoso secondario di 18 specie desertiche Fezzanesi, dando di ciascun legno una descrizione micrografica completa. I caratteri anatomici ed ecologici dei legni studiati suggeriscono la sistemazione delle specie a cui essi appartengono in quattro categorie ecologiche diverse.

L'A. discute poi le caratteristiche ecologiche-anatomiche delle specie appartenenti a ciascuna categoria ed il loro diverso grado di adattamento alla vita in ambiente desertico (1).     

Portamento Rampicante - Volubile Provocato,in Alcune Piante,dal Trattamento Con Acido Gibberellico

Summary

In this communication reports are given on experiments and observations regarding treatment of several plants with Gibberellic acid and consequent manifestations of stem growth with twining-climbing behaviour. This phenomenon has been observed in plants which normally never present similar behaviour (Lactuca Scariola L.) and it has been provoked in plants genetically more or less predisposed (Phaseolus vulgaris L. cult. “aquila rossa” e Soja hispida Moench. cult. “Castelli” and “Giessner”). Normally climbing plants, as Ipomaea versicolor, has been treated for control.

In Phaseolus and in Soja the action of Gibberellic acid has been very considerable as plants thus treated have assumed all the characteristics of climbing growth. Photos and Tables clearly show the extent of such action.

In Ipomaea, in conformity with work hypothesis, we can clearly observe the meagre advantage in growth of internodes following tratment with Gibberellic Acid.

The purpose of these experiments, as is obvious, is to lay the bases for a physiological interpretation of climbing behaviour. It is clear by results obtained that, subordinately, at least, to certain qualitative structural manifestations, plants thrive with or without climbing behaviour according to whether their growth is more or less rapid and of different proportions. Increasing growth rapidity by tratment with Gibberellic Acid, we may obtain an twining growth phenomenon in plants genetically more or less predisposed towards said phenomenon, in those plants, that is, which in special environnmental conditions may sometimes, although exceptionally, manifest the tendency to climbing growth. This effect is obtained on plants in which we do not usually meet these phenomena but which, evidently, have the possibility of manifest them provided that am exceptional growth stimulas is operating.

From what above said we can deduce a first and simple work hypothesis, which will be the object of study in the near future, and which prospects the possibility that typically climbing plants owe their behaviour to the capacity of regulating their growth also in consequence of the formation of appropriate quantities of substances with gibberellinlike action and lacking some growth inhibiting condition. The same thing might be true for the plants which are climbing only on exceptional occasions, and a similar possibility might be given to the plant by particular external conditions in which the individual is formed, grows and develops.

Is is interesting also to observe that the analogy between climbing behaviour induced by Gibberellic Acid and natural one, extends also to leaf expansion behaviour and to other characteristics facts included in the field of etiolated plants.

Successive experiments will give us a deeper knowledge of this particular aspect of climbing behaviour and will define the conditions in which movements of shoot apex take place under the action of Gibberellic Acid and structural manifestations inherent, in comparison to those of naturally climbing plants.     

Le Torbiere Italiane

Riassunto

L'A., in questa prima parte del suo studio delle torbiere italiane, ne fa un minuzioso elenco, con indicazioni topografiche e richiami bibliografici.     

Note ecologiche su Petroglossum nicaeense (Duby) Schotter (Phyllophoraceae)

Abstract

Ecological researches on Petroglossum nicaeense. — Some environmental variables of the biotope where P. nicaeense grows are described; that is a superficial cave of the coastline of Bari (Adriatic). The distribution of this species in the Mediterranean is outlined and a classification of this alga on the basis of the criterion of the biological types is tried.     

Licheni Nuovi O Interessanti Delle Coste Italiane

Abstract

New or interesting Lichens of italian coasts. — The autor describes a lichen new to Italy, Acarospora microcarpa (Nyl) Wedd, a mediterranean species, found in southern France only hitherto. The lichen was gathered on the tufs rocks of the Isle of Procida; so the species is classed among the cryptogamic flora of phlegrean tufs.

The presence of Acarospora trachytica Jatta on the isle of Procida is therefore indicated, a species that is somewhat rare and known so far only on the Island of Ischia and Vesuvius.

Some new places for the marine lichen, Verrucaria symbalana Nyl. are reported, and the particular ecological interest of the species and its full geographical placement considered.

Finally, new places for Lichina confinis Ag., in Italy are given. This is a marine species of considerable ecological interest.     

Piante critiche delle Alpi Venete

Abstract

INHIBITION OF GLUCOSE-6-P DEYDROGENASE BY OXIDATION PRODUCTS OF NATURAL PHENOLS. — The inhibition of Gl-6-P dehydrogenase activity found in highly concentrated homogenates from potato tuber tissue, seems due to natural occurring orto-di-quinones, such those arising from polyphenoloxidase catalized oxidation of chlorogenic acid, caffeic acid, and tyrosine.

These compounds strongly inhibit Gl-6-P dehydrogenase activity of the potato tuber homogenate as well as that of purified Gl-6-P dehydrogenase from yeast. The inhibition effect appears much stronger when the diphenols are oxidized in the presence of the Gl-6-P dehydrogenase. Gl-6-P and TPN efficently protect the enzyme from the inhibition. Ascorbic acid prevents the inhibition by mantaining the diphenols in the reduced form, but is ineffective in reversing the inhibition.     

Le Piante e la Musica. Riassunto

Abstract

The Plants and the Music. — The valuable contribute that the Biology may offer to the scientific study of the « essence » of the Music is pointed out. The plants as Animals and as remotest ancestors of the humanity, contribute to form what the A. calls the « Promusic », that is the natural and necessary starting-point of the evolution of the Music, which is exclusive work of the man. The Plants particularly, although indirectly, showing wonderful instances of transformations and associations of simple in complex forms, as well of colours and scents, have certainly inspired to the Man the Harmony, which is just in Music the Art, unknown to the Ancients, in associating aesthetically sounds and timbres.