Caratterizzazione citologica e citochimica del nefrone di Cyprinus carpio L.

Ricerche eseguite e pubblicate con il concorso di un contributo del C. N. R.     

Caratterizzazione aerosporologica del comprensorio di imola in due diverse sedi di rilevamento

Riassunto Sono stati esaminati 4 anni di campionamento aerosporologico del Comprensorio di Imola. Le rilevazioni sono state eseguite in due sedi diverse per condizioni fitogeografiche, distanti circa 6 chilometri l'una dall'altra: negli anni 1983–84 presso l'Ospedale M. Malpighi di Imola, negli anni 1986–87 nel centro della città di Imola. E' stata riscontrata una parziale sovrapposizione dei dati aerosporologici per le specie di interesse allergologico, a conferma della significatività del campionamento per valutazioni cliniche correlabili.      

Studio preliminare sulla tipologia della vegetazione sommersa del Canale di Sicilia e isole vicine

Abstract

Preliminary studies on the marine phythobenthic communities in the Straits of Sicily and adjacent islands. — The results of algological researches carried out by the Gruppo di Algologia of the S.B.I. in the Straits of Sicily and adjacent islands are reported. 288 species have been collected, 275 of which have been identified: 160 were Rhodophyta, 62 Phaeophyta, 32 Chlorophyta, 16 Cyanophyta and 2 Angiospermae. The vegetational research leads to the following conclusions: 1 - the harbour areas (Pantelleria, Malta: loc. 1 and 11) show a nitrophile vegetation, particulary near La Valletta where an almost pure population of Pterocladia pinnata is found; 2 - there are important biogeographical differences between Pelagie islands (Lampedusa, Linosa) and Pantelleria. In fact the former ones have an algal flora composed mostly of eastern mediterranean species, whilst the latter shows strong affinities with the north-african basin, as is demonstrated by the rich well developed belt of Cystoseira sedoides; 3 - several species of atlantic origin, such as Callophyllis laciniata, Peyssonnelia coriacea, P. inamoena and Castagnea chordariaeformis, have been found on the banks (loc. 3, 6, 7).     

La Posidonia oceanica: problemi di ecologia,di funzionamento e di biologia

Abstract

The functional roles of seagrasses in the economy of coastal waters are to be fully realised and more clearly delineated. The biology, ecology and energetics of seagrasses meadows of the Mediterranean Sea, and in particular of Posidonia oceanica inclusing the stabilization of coastal sediments, this role as a base for major detrital food chains, nutrient resources contributory to general productivity of the open sea and the support of dense epiphytic communities, are discussed.     

Fenomeni di Inattivazione e di Riattivazione Enzimatica in Endospermi di semi di Ricino

Abstract

Inactivation and riactivation of enzymes in endosperms of castor bean seeds. — On the basis of previous results, the possibility has been investigated of the reversible interconversion of active and inactive form of enzymes in castor bean seeds, during their development.

The results described here indicate that:

1. the activity of some glycolytic enzymes increases greatly (81% and 400% increase of, respectively, Gl-6-P-dehydrogenase and aldolase) upon incubation of dry seeds for few hours at 4 °C.

2. The decrease of enzyme activity upon dehydration of seeds and the increase during the subsequent imbibition can be shown reproducibly.

3. This same observation is made for oxygen uptake.

These results are interpreted to indicate the reversible inactivation of enzymes caused by dehydration of seeds.     

Metabolismo di Quiete e Metabolismo di Crescita

Summary

The changes in carbohydrate and phosphorus metabolism of tomato ovaries stimulated to growth by pollination or auxin treatment found in previous studies prompted an investigation of the enzymatic systems concerned. In this research, the effects of pollination and of auxin treatment on phosphorylase and on phosphatase activity were studied. Phosphatase splitting inorganic P from adenosine triphosphate was characterized as different from that acting on glycero- and hexose-phosphate by the difference in inhibition by beryllium and fluoride.

Two phases of growth occurring during the earlier stages of fruit development were clearly defined by the behavior of the enzymes considered. During the first (induction) phase both phosphomonoesterase and ATP-ase activity markedly dropped. This was followed by a marked rise in activity during the later stages of growth.

Phosphorylase activity, unlike that of the phosphatases, showed no relationship to the two phases of growth, and increased steadily during the period of observation. This agreed with the rate of starch synthesis observed in the growing auxin treated or pollinated tomato fruits.

Changes in the activity of these enzymes in the not pollinated, not auxin treated ovaries during the period of observation were, on a comparative basis, very small.     

Ricerche Comparate Sulla Morfologia e Sulla Fisiologia di Larix e di Picea

Abstract

Comparative researches on morphology and physiology of PICEA and LARIX. The chlorophyll content of seeds and seedlings during germinations in darkness. — Very different are the chlorophyll contents of the seeds and the seedlings of Picea excelsa and Larix decidua grown in darkness.

In Picea chlorophyll is abundantly synthetized in cotyledons in the passage from seed to seedling stages. In Larix however this synthesis is very poor. These differences are more evident after the outgrowth of cotyledons from the primary endosperm and its exhaustion.

If seedlings of both species are exposed to 3.000 lux of light intensity for 24 hours, after development in darkness, one can observe much stronger chlorophyll synthesis in Larix cotyledons than icea.

These figures quanti atively express the different light-dipendence of chlorophyll synthesis in these two plants and offer a more adherent interpretation of the different ecological behaviours that are caracteristic of these two plants.     

Sul Presumibile Antagonismo Tra Sviluppo Vegetativo e Fiorale e Su Un Nuovo Caso di Formazione di Gemme e di Foglie Su Spine di Aurantiaceae

Riassunto

L'A. facendo delle osservazioni comparative tra le caratteristiche di sviluppo vegetativo e fiorale rilevate tanto sui rametti ordinari che nei casi anomali di formazione di gemme su spine di Aurantiaceae mette in rilievo il presumibile antagonismo tra sviluppo vegetativo e fiorale che si verifica in genere tra le due importanti attività fisiologiche della pianta.

Nello stesso tempo dà notizia di nuovi casi di formazione di gemme e di foglie su spine di Citrus limonum L. che, confrontati con quelli descritti in precedenti lavori dell'A. riguardanti lo sviluppo di fiori su spine di Aurantiaceae, confermano che gli abbozzi fogliari contigui alle gemme si evolvono regolarmente quando la gemma sia polarizzata nello sviluppo vegetativo o sia allo stato latente, mentre restano in genere allo stato rudimentale quando la gemma viene a polarizzarsi verso lo sviluppo fiorale. Ciò si verifica in generale negli abbozzi fogliari che si sviluppano sulle rachidi fiorali ed eccezionalmente in quelli che sono in rapporto con la gemma che dà origine ad una rachide fiorale.