Ricerche Embriologiche Sulle Martyniaceae

Riassunto

L'A. ha studiato lo sviluppo del gametofito e dell'albume in Proboscidea Jussieui Steud. e in P. lutea Stapf: il gametofito risulta di tipo normale e Palbume di tipo cellulare fino all'inizio. Particolare attenzione è stata posta nel descrivere le caraterristiche morfologiche di due tessuti di nutrizione dell'ovulo: una modesta epistasi ed una ipostasi di proporzione notevole, fornita anche di un cambiforme. E stata pure messa in rilievo l'importanza dell'epidermide. Interna del tegumento per il mantenimento allo stato embrionale dei tessuti circostanti. Il numero dei cromosomi è 2n=30 in ambedue le specie.     

Ricerche Embriologiche sul Genere Thalictrum Embriologia di Thalictrum Angustifolium L. v. flavum L

Abstract

Embriologycals researches in the thalictrum genus. — Embriology of Thalictrum angustifolium L. v. flavum L.

In this research has been studied the development of the female gametophyte of Thalictrum angustifolium L. v. flavum L.; it has been found a tetrasporic bipolarized type: the Pyretrum type, with sixteen nuclei.

The gametophyte is characterized by cellularization of every antipodal nucleus.

Besides this is a new type in the Thalictrum genus, supposing that in others species of this genus, has been recognized the Normal type.

The author supposes another type in this specie, probably a development of the tetrasporic tetrapolarized type, of which he will refer when the necessary elements emerge.

In this specie the microsporogenesis is simultaneous.     

Ricerche Citotassonomiche in Artemisia Vulgaris L. Ed Artemisia Verlotorum Lamotte

Abstract

Cytotaxonomical studies in Artemisia vulgaris L. and Artemisia verlotorum Lamotte. — Karyotype analysis of A. vulgaris and A. verlotorum has shown in the first species, in agreement with previous data, a chromosome number of 2n=16 and in the second the chromosome number of 2n=48 which does not agree with previous data. This seems to be the first case of polyploidy observed in Artemisia with basic number eight. A few specimens of A. verlotorum had shown 2n=48 + 2B chromosomes. The comparison of karyotypes has shown that, while the two species have, in some respect, the same degree of symmetry (ΣL%=57; ΣC9% = 43), the quality of their chromosomes is different (see karyotype formulas). We see no explanation for such an unlikely phenomenon.     

Ricerche Embriologiche Sul Genere Thalictrum. II. Embriologia e Cariologia Di Thalictrum Lucidum L. e di Thalictrum Minus L. Subsp. Minus

Abstract

Embryological researches in the «Thalictrum» genus. II. Embryology and caryology of «Thalictrum lucidum» L. and «Thalictrum minus» L. ssp. «minus». — In their development the female gametophytes of Thalictrum lucidum L. and Thalictrum minus L. ssp. minus follow the Normal type. In the female gametophytes of these species several types of antipodal cells occurs such as: their considerable enlargement, formation of many antipodals polyploid or polinucleated antipodal cells. In these various types, however, a rapid regression of the antipodals occurs. In T. lucidum some tendency to a disposition of the tetrapolarized type has been verified. The chromosome number has been confirmed to ben 2n=28 in besides, in the pollen development, many cases of regression of the microspores has been verified. The chromosome number has been confirmed to ben 2n=28 in Thalictrum lucidum L., and has been found to ben 2n=14 in Thalictrum minus L. ssp. minus, a new number in this species, which was earlier reported to have 2n=42.     

Ricerche Sugli Stami dei Fiori Sani e Parassitati del Melandrium Album (Miller) Garcke

Abstract

Researchs on the stamens of the healty and parasited flovers of Melandrium album. — The author has examined the structure of the stamens filaments in the healthy and parasited flowers of Melandrium album. The structural modifications induced by the mycelial hyphae of Ustilago violacea expecially in such filaments are pointed out.     

Artemisia Caerulescens l. var. Cretacea Fiori: Indagine Morfologica,Anatomica ed Analitica

Abstract

ARTEMISIA CAERULESCENS L. var CRETACEA Fiori: its morphology, anatomy and santonin content. — Artemisia caerulescens L. var. cretacea Fiori, endemic of the loamy soils of Romagna and Tuscany, has been collected near Siena and specimens have been submitted to morphological, anatomical, systematic researchs.

The names of previous botanists who have collected this plant in the surroundings of Siena have been listed.

The big underground apparatus of Artemisia and the variable morphological characters of the species, expecially for the inflorescence, have been put in evidence.

The most outstanding anatomical characters of var. cretacea are the following:

1) in the overground stem (that means in the inflorescence axis) glandular hairs and T hairs are present, persisting also when the cork tissue is formed; the collateral vascular bundles are surrounded by a sclerenchymatic cap, outside the phloem; the parenchyma cells of the protoxylem area in the primary and secondary structure are not lignified; some cambial cells show lignified walls.

2) in the cortical parenchyma of the underground stem occur frequent cell division; the sclerenchyma cap cells are absent. The phloem is mixed with fibers and crossed by tangential parenchyma. Growth rings or sector rings are evident in the xylem; between the wood rings, layers of parenchyma are interposed. Several growth rings may be formed during one year.

3) the young root is triarch or tetrarch, the cells of the cortex undergo frequent divisions. The grown up root resembles closely the underground stem.

4) The leaves are isobilateral and provided with aquiferous parenchyma.

The flower buds of many Artemisia of the section Seriphidium, to which Artemisia caerulescens var. cretacea belongs, produce santonin which has anthelmintic properties.

The colorimetric determination of the drug contained in the var. cretacea had showed that it has a santonin content of g 0,56%.     

Ricerche Morfologiche e Anatomiche Su Mimosa Pudica L.

Summary

Firstly, the author describes the anatomical and histological structures of Mimosa pudica L. during the stages of development of the young plant prior to the appearing of cambium. She then discusses, in the light of previous literature on the subject, the three principal features of Mimosa pudica: herbaceous bearing, stable tetrarchy with intercotyledonal bundles along the plumule, and small sized germination.

Finally, the author concludes that Mimosa pudica appears to be an individual with tree-like rather than herbaceous symmetry (stable tetrarchy), in which the size of germination has diminished parallelly to reduction in size of the adult individual.     

Chemical constituents and biological activities of Senecio aegyptius var. discoideus Boiss

A new eremophilane sesquiterpene, 1-beta-hydroxy-8-oxoeremophila-7,9-dien-12-oic acid (1), in addition to two known flavonol glycosides, rutin (2) and quercetin-3-O-glucoside-7-O-rutinoside (3), was isolated from the ethyl acetate fraction obtained from the aqueous alcoholic extract of the aerial parts of Senecio aegyptius var. discoideus Boiss. (family Asteraceae). The chemical structures of the isolated compounds were established by 1D and 2D NMR analysis (1H, 13C, COSY, HMQC, HMBC), MS and UV data, and through comparison with the literature. The ethyl acetate fraction and the isolated rutin showed significant cytotoxic activity against colorectal carcinoma (HCT 116) and to less extent against brain (U 251) and breast carcinoma (MCF 7). The ethyl acetate fraction showed a significant level of activity against Klebsiella pneumoniae, while the total extract showed the best antifungal activity against Candida albicans and Saccharomyces cerevisiae. DPPH radical scavenging activity of the ethyl acetate fraction was significant (96.7%) when compared to ascorbic acid. It also showed anti-inflammatory activity but no diuretic effect.     

Statistische Onderzoekingen bij Senecio vulgaris L

Ohne Zusammenfassung     

Ricerche sul meccanismo di azione della cocliobolina. A: effetti della tossina su fettine di tubero di patata in riposo

Abstract

STUDIES ON MECHANISM OF COCHLIOBOLIN ACTIVITY. A: EFFECTS OF THE TOXIN ON FRESH POTATO TUBER SLICES. — Cochliobolin, a toxic compound produced by Helminthosporium oryzae, causes inorganic phosphorus leakage from fresh potato tuber slices, higher amounts being found in incubation media with higher toxin concentrations and for longer incubation periods. Organic compounds, also, are released by potato tuber slices, like phenolic products, large amounts of sugars, and some aminoacids, alanine, lysine, tyrosine, valine and γ-aminobutirric acid, which have never been observed in the incubation meida of untreated slices. Cochliobolin uptake by fresh potato tuber slices does not take place actively or, anyhow, at a metabolic level. Indeed, neither 2,4-dinitro-phenol (at concentration, pH, and incubations periods apt to reduce active uptake), nor low temperatures (0–2°C) prevent toxin uptake. Potato tuber slices are not affected by cochliobolin, unless kept at 25°C, and this fact suggests that while toxin uptake does not interest metabolic pathways, it might affect some phase, or structure, essential to cell metabolism. The locus of toxin activity seems therefore to be identified with its influence on cell absortion and retention activities, of products essential for metabolic processes. Thus the impairing of cell permeability, possibly affecting the processes or the structures which regulate the active uptake, seems to be, at the moment, the only evident interpretation of the phenomena observed.     

Ribes rubrum L. var.pseudo-petraeum Baenitz

Ohne Zusammenfassung     

The behaviour of wasps (Vespula germanica L. andV. Vulgaris L.) when foraging

Summary While foraging on dead adult and pupal honeybees, individual wasps showed little conformity in the order in which they dismembered their prey; they attempted to take as large loads as possible and preferred abdomens and thoraces to heads.Although wasps always removed some of the appendages from thoraces, especially the hind and middle legs, the presence of these appendages did not encourage foraging or facilitate recognition of the prey.Pupae were preferred to newly emerged bees, and newly emerged bees to old bees, probably because of the difference in hardness of the cuticle. Whereas wasps learnt to divide adult bodies at the neck and waist, they showed considerable adaptability when dismembering pupae and when confronted with unusual situations. Although individuals tended to become conditioned to collecting one type of prey, some changed from collecting adults to collecting pupae.Wasps could easily be enticed away from meat by offering sugar syrup, but the change from syrup to meat was much more difficult, although it happened occasionally.Some wasps attempted to defend a supply of food against other would-be collectors. Despite their wariness of each other, wasps were attracted to the sight of others at a food source. The frequency with which a wasp continues to visit a site that has ceased to yield food depends on its previous foraging experience there.     

Ricerche Sulla Vegetazione Della Valsesia. VII. Notholaena Marantae (L.) Desv. in Valsesia

Abstract

Researches on the vegetation of Valsesia. VII. «Notholaena marantae» (L.) Desv. in the Sesia Valley. — It's hereby described a station of Notholaena marantae (L.) Desv. near «Giavina Rossa» (Valsesia-Piedmont, Italy). This is probably the only place in the whole valley. The fern grows in a kind of ground formed by peridotitic rocks and on a little dry wall supporting the debris. The fern presence in a wooden valley, and under an oceanic climate could be a very interesting subject for hystorical geobotanic researches.     

Alkaloid profile of Bulgarian species from genus Senecio L

Twenty-seven pyrrolizidine alkaloids were identified by a detailed phytochemical study and GC/MS analysis on twelve Bulgarian species from genus Senecio. Twenty of them are new for the corresponding species. Other six structures remain tentatively identified.     

金瓜和白瓜花叶病毒病病原的初步鉴定

崇明是上海出口蔬菜生产基地之一,也是国家级的绿色食品园区之一,具有生产绿色蔬菜商品的生态环境和资源优势.