L'amido E L'endosperma Delle Cariossidi Dure E Tenerizzate Di Triticum Durum Desf

Abstract

Starch and endosperm of vitreous and starchy (yellow-berries) kernels of Triticum durum Desf. — Starch and endosperm in kernels of T. durum Desf. have been examined in relation with the problem of the origin and nature of the vitreous or starchy texture which this tissue shows in the ripe fruits. This research has demonstrated that the starch of the vitreous differs from that of the starchy kernels in the shape, respectively irregular and regular; in the distribution of the frequencies y versus the length of the diameter x which is exponential and of the type log y = log a — x log b, in the vitreous kernels the value of log b is generally lower than in the starchy kernels; in the submicroscopical texture, because the irregular grains of the vitreous kernels do not show either birefringence or polarisation cross and are coloured with Congo red: starchy kernels behave quite differently. The starchy kernels are also more swollen and regular, their apparent specific weight and their nitrogen content being less than in the vitreous; the process of starchiness is always in close contact with fibro-vascular bundle of the row; in the starchy cells the cytoplasm shows some interruptions of continuity which leave partly uncovered the starch grains; the endosperm and the starch of the hard kernels wetted with water or placed in moist atmosphere become micro- and macroscopically similar to the starchy ones; in the starch the process of trasformation of the orderly into the amorphous texture is reversible, but for this to happen the only contact with water is insufficient; according to the treatments the vitreous kernels might show a decrease in their nitrogen content. Both starch types are connected with the presence orabsence of slightly bound water; the hypothesis which considers the nitrogen supply of the fruit as immediate cause of the endosperm texture is criticised and it is considered more plausible that such cause might be the different structure and texture of the cytoplasmatic gels during, in function of temperature and moisture.     

Ciclo Di Accrescimento E Differenziazione Delle Gemme in Piante Perenni Nel Territorio Di Bari

Abstract

The secondary wood of the fig tree is characterized by a remarcable degree of dimorphism and the concentric rings d o not correspond to yearly recurring growth periods. These false rings are formed by alternating tangential strips of fibers and wood parenchima. During each vegetative season three or four of these strips arc laid down by the cambium.

During the year the cambium undergoes a period of activity and a period of rest, but there is no histological difference between the early wood and the late one, differentiated just before the restring period. In consequence the so-called annual wood rings do not exist in the fig tree stem.     

Ciclo Di Accrescimento E Differenzazione Delle Gemme in Piante Perenni Nel Territorio Di Bari

Summary

The evolution of cambial activity during one year in Viburnum Tinus L. in Bari has been studied. The research seems to be particularly difficult in this evergreen shrub. The wood is of the porous diffused type with scarse evidence of wood rings. The vessel diameter varies rather irregularly in the wood ring; on the other side the fibers show wide variations and may be assumed as a good index of the wood ring evolution. Both in the branch and in the stem only one wood ring each year is formed.

Cambial activity prosecutes during the whole year, with an irregular step. During the period July-beginning of September the cambium devides very slowly, or possibly stops deviding.

The early wood is produced earlier in the branch than in the stem; namely in February-end of May in the branch and in March-beginning of June in the stem. The stimulating growth stuffs evidently proceeds downwards from the top to the base of the plant. The relations between ring evolution and climatic factors are discussed. The peculiar cambial poussée during the month of June seems to be correlated with the exceptionally aboundant rainfall of May in Puglia in 1947.

The late wood is formed during the other months discontinuosly. The alternation between the two phases of cambium division and wood lignification has been focussed. The wood ring in Viburnym Tinus is annual and the early wood differentiates in spring.     

Quinta Serie Di Rinvenimenti Floristici Marchigiani E Di Osservazioni Diverse Sulla Flora Delle Marche

Abstract

The A. refers about the most interesting discoveries and observations performed during the year 1958 in the limits of the flora of Marche.     

Ciclo Di Accrescimento e Differenziazione Delle Gemme in Piante Perenni Nel Territorio Di Bari

Summary

Growth CYCLE AND BUDS DIFFERENTIATION IN PERENNIAL PLANTS GROWING IN Bari AREA. 1) Observations ON Ficus Carica DURING THE YEAR 1946.

The fig tree under observation in Bari started its growth (during the year 1946) in the second week of March and stopped in June second half. The growth period lasted about three months (tab. 1 e 2; diagr. 1).

The most rapid growth occurred during the second week of May (tab. 2; diagr. 1).

From the diagr. 3 it appears that in the fig tree the growth end corresponds at the beginning of the rainless weather; in the meantime the temperature rises gradually (diagr. 4). The atmospheric humidity subsists high also during the summer rainless period (diagr. 5).

Among the four shoots examinated, only one showed a further slow lengthening (13 mm.) from 2nd. August to 6th September. The three others did not grow anymore from June 15 (tab 2; diagr. 1).

The young shoot internodes have different lengths. The basal ones are shorther than the middle ones, which appeared during this speedly growing period (diagr. 2); the last two internodes are very short, so that the nodes are rather contiguous. At each node one leaf unfolds, with two large stipules, which soon fall; on the very last node the stipules do not fall, sheltering the young apical bud, which they completely close in. The corresponding leaflet scarsely grows, falling soon. Neverthless the protection of the two stipules, the first leaflet of the apical bud withers and falls frequently as soon as the bud unfolds at the beginning of spring (fig. 1).

Each leaf axil bears two or three buds (fig. 7). When two buds are present, one is a fruit bud and the second a vegetative one (figg. 11 e 13), when three buds are present, the two lateral ones develop into flowers, while the middle one grows into a vegetative shoot (fig. 12).

The very first sign of the fruit character of a bud is the flattening of the apical bud meristem (fig. 7); successively it deeps into a cuplike body (figg. 8 and 9); on the bottom and along the walls of the cup the female floscules are developing (fig. 10).

The first sign of the vegetative character of a bud is, after the formation of the leaf meristem outline, its evolution with the caratteristically lobed leaves and stipules.

As far as a given height along the shoot (as far as the sixth node in our shoots) the syconia prolong their growth after the shoot lengthening has stopped and ripen completely during August-September (forniti or September-figs). From a certain level ahead, as far as the apical bud (from the seventh to the tenth node in our shoots) the syconia cease their development about contemporarly the vegetative shoot. They are three or four mm. wide and the little flowers are clearly distinguishible inside. So they hang from the nodes as late as next spring time, when they begin to grow again, ripening in June (fioroni or June-figs).

September and June figs then represent a continous acropetal fruit series differentiating at each leaf axil, as soon as the leaflets unfold during the shoot development. We must point out that while the September figs reach the ripe condition through a stopless development in the same year, the June figs stop their growth at a given time, standing a resting period and begin to grow again, ripening the next vegetative season.

As to explain such a behaviour, the presence of an inhibitory stuff is prospected, produced from the more developed figs, which attain a given stadium of development. This stuff would act on those figs, which have not yet reached this particular development stage.

The summer drought checkes the shoot growth and the bud differentiation. The flower buds, which have been too early stopped in their development, are not able to grow again the next season and fall during the apical bud unfolding. Such a condition occurs in the last leaf bud (fig. 4) and in the first leaflet bud inside the vegetative tip (apical bud) (fig. 5). At the beginning of the new vegetation season the shoot awakes with the differentiation of those buds, which did not yet differentiate at the axil of the leaflets inside the apical bud (fig. 6). (See fig. I, where the phenomenon is schematically reproduced).     

Rendiconti Delle Sedute E Brevi Comunicazioni

Abstract

The development of effective strategies to rehabilitate compromised environments is one of the major challenges facing the postindustrial society, since most of the habitats are becoming progressively polluted due to indiscriminate discharge of contaminants generated by anthropogenic activities. Several aquatic photosynthetic organisms can be used to treat wastewaters in primary and tertiary treatments, including cyanobacteria, algae and higher plants. In this review, we summarize the results obtained in the remediation of polluted waters by photosynthetic organisms and discuss the future perspective of phytoremediation.     

Rendiconti Delle Sedute E Brevi Comunicazioni

Abstract

Totally, 26 xerohalophytic species belonging to the associations Cakilo-Xanthietum italici and Echinophoro-Elymetum farcti were registered at the Velika pla?a beach (Montenegro); they were distributed following the spatial succession common in this type of habitat. Three transects of different terrain morphology (positioned perpendicularly to the shoreline) were surveyed to establish if there were any differences in the floristic composition and species distribution due to the configuration discrepancy. Moreover, each transect was divided into zones: The first zone from 0 to 30 m inland, the second zone from 30 m to 60 m inland, and the third zone from 60 m to the end of beach (75–115 m, depending on transect length). The floristic composition was relatively uniform in the different transects. However, the number of individuals per species differed significantly among these transects. An analysis of the qualitative composition of transects/zones showed high differences between zones within transects I and II, whereas species composition of zones within transect III was mostly similar. When analyzing the quantitative composition of species, a positive correlation between the distance from the shoreline and the number of individuals per species in transects I and II was registered for most analyzed species (Spearman correlation, p < 0.001). This indicates that terrain configuration affected the ability of present species to become established and propagate.     

Flora Delle Acque Circostanti L'Isola Di Pianosa (Is. Tremiti)

Abstract

The marine flora of the Isle of Pianosa (Isles Tremiti). – The little Isle Pianosa (Middle Adriatic) presents an algal flora typical for clear, deep seas. Its main components are here described. Endolithic flora on calcareous rocks has been particularly well examined.     

Contributi Alla Conoscenza Della Vegetazione Ruderale Torinese: Indagini Sulla Flora E Sui Consorzi Vegetali Di Un'Area Incolta Ed Abbandonata Nella Zona Centrale Dell'Abitato Di Torino

Abstract

The composition of the flora growing on the ground where Turiner Polytechnic School was once located and then destroyed by an air bombardment during the Second World War was investigated. The area of this ground of 15.000 m²., is in the central zone of the town and is limited by Cavour, San Francesco da Paola, Giolitti and Dei Mille Streets.

The actual flora consists of about 160 taxa, making an ensemble of ruins and dry grounds plants, but with an evident contribution also of meadow plants, which, under favorable conditions, group themselves the same as neglected meadows in the suburbs.

The analysis of this vegetable grouping suggests some assumptions on the dynamics of the vegetation and on the transformations occurred since the day of the pioneering.

Some rare or in town ruins Turiner flora unknown plants are described, which could be saved there thanks to the fact that the continued disturbing and treading action of man was avoided; in fact the admission to the above-mentioned area had been precluded.

A list of the observed or collected taxa follows, with the addition of some phyto-phenological findings. A summary of the occurring of the observed patterns, according to their belonging to the vegetation bands and to their diffusion area, concludes the investigations.     

Osservazioni E Considerazioni Sul Fenomeno Della Micorrizia al Piccolo San Bernardo

Riassunto

L'A. espone i resultati di osservazioni compiute sul fenomeno della micorrizia, constatando fra l'altro che esso si attenua nelle piante alpine coltivate nella Chanousia rispetto a quelle spontanee dei dintorni. Enuncia l'ipotesi che i componenti di un'associazione vegetale sieno fra loro strettamente collegati a causa del considerevole sviluppo del micelio micorrizogeno, che può passare anche dalle radicì di una specie a quella di un'altra.     

Pugillo Di Licheni Dell'Abissinia E Dell'Eritrea

Abstract

The long pollen sequences from four volcanic lakes of the Lazio région are presented in order to outline the history of flora and vegetation on the Tyrrhenian side of Central Italy during the last hundred thousand years. The four long pollen records correlate satisfactorily with each other and reflect climatic changes at least at regional scale. Particular attention is paid to the development of arboreal vegetation during the last glacial. The local name “Lazio Complex” is given to the seven main fluctuations of trees of the Pleniglacial (from about 60,000 to about 30,000 years B.P.). The history of Zelkova, Abies, Picea, Fagus, Corylus, Ulmus, Carpinus betulus, Tilia in central Italy is outlined.     

Flora E Vegetazione Della Formazione Ofiolitica Di Rossena

Summary

The A. is dealing in his research the groups of ophiolitics rocks of Rossena (Reggio Emilia). He enumerates the kinds found in the formation and describes the different types of association wich colonise the diabase and the largest of the little periferic tops of serpentine. He ascertains in this rock the lack of the relict species.     

Ciclo di Accrescimento E Differenziazione Delle Gemme in Piante Perenni Nel Territorio di Bari

Summary

Growth cycle and buds differentiation in perennial plants growing in Bari's area. — V. The evolution of the wood ring in Rhammus Alaternus L. from December 1946 to March 1949.

In Rhamnus Alaternus L. the cambium awackens in March with the production of an early wood, characterized by large vessels and loose fibers. It keeps on dividing the following months, producing intermediary wood, whose vessels become narrower and narrower. In June the wood ring is almost complete and the cambial activity slows down. In July late wood is formed, with narrow tracheae and highly lignified fibers. From August to February cambial activity is very scarce and irregular, in the wood produced fibers being tangentially compressed.

In a young branch of R. A. cambium becomes suddenly active in February, that is one month before than in the stem, it goes on during the month of March-June, with an evident diminution in the size of the wood elements. This diminution of size instead of being regular, shows some oscillations, expecially during the month of May. In Sept. the cambium starts again dividing, but rather poorly and irregularly, forming some vessels a little wider than the preceeding ones, so that an incomplete false ring is formed only in some points of the branch. As a rule the autumn wood is a typical late wood. This scarce and irregular cambial activity goes on also during Oct.-Dec. In January is more active and forms rather wide vessels in comparison with those formed in the preceeding month. This new formed wood however does not show the characteristics of the early wood of a new ring.

Concluding, the characteristics of the cambial activity of A. R. are

In the stem: 1) March: early wood. 2) March-June: intermediary wood. 3) July: late wood, resting period. 4) At the end of Autumn a scarce production of late wood is sometimes possible.

In the young branch: 1) February: early wood. 2) March-June: intermediary wood, with positive and negative oscillations in the vessels width. 3) At the end of June the late wood is already differentiated. 4) July-August: resting period. 5) Spt.-Juan.: the cambium starts again dividing very scarcely and producing a transition wood between the two rings. This wood can be regarded neither as a true ring nor a false one, it represents rather the last phase of the late wood formation. 6) In the young branch of the female specimen the cambium starts dividing somewhat later than in the male one. 7) The wood ring width does not vary much in relation to the yearly amount of rainfall. The lack of relation between rainfall and ring width is particularly evident in 1948 (a rainy year). The, «Compleasance» of R. A. could show that this species is, in Puglia, in its own habitat. On the other hand it is rather peculiar that R. A. forms only one wood ring during one year, with production of early wood during the spring, and of late wood in the autumn, instead of producing a second autumn ring following a distint summer rest, as could be expected.     

Naturalizzazione E Riproduzione Spontanea Di Piante Ornamentali Nella Liguria Occidentale

Abstract

Effects of the growth-retarding compounds «CCC» and «AMAB» on the growth and alkaloidal content of Datura Stramonium L. — Datura Stramonium L. was administered two fortnightly-doses of 200 cc 10 ^-2 M solutions of (2-cloroethyl)-trimethylammonium chloride (CCC) or (allyl)-trimethylammonium bromide (AMAB), poured on the soil of every pot. In the treated plants were noted shorter and thicher stems and petioles and leaves larger in size and darker green than in the controls. Yields of leaves in CCC and AMAB-treated plants were not significantly changed while root fresh and dry weights were decreased. The per-cent concentration of total alkaloids in the leaves and roots of both CCC and AMAB-treated plants was not significantly different in comparison with that of normal plants. Therefore the A. assumes that the growth-retarding chemicals must not interfere with alkaloidal synthesis.     

Comparative demographic analysis of three Neobuxbaumia species (Cactaceae) with differing degree of rarity

In this study we use a demographic approach to analyse the differing abundance of three congeneric columnar cacti: Neobuxbaumia macrocephala (the rarest), Neobuxbaumia tetetzo (intermediate), and Neobuxbaumia mezcalaensis (the most common). Populations of these species were studied in the Tehuacan Valley (Central Mexico) over a 3-year period. We employed traditional models and life table response experiments (LTRE) to explore the association between particular demographic traits and the degree of rarity of each species. Most matrices showed population growth rate () values close to unity; the only exception was N. mezcalaensis in 2001–2002 (=1.091±0.088). In the three species the highest elasticity values corresponded to entries referring to the stasis of pre-reproductive plant and small adults. However, the LTRE indicated that most important differences in the values between years and species were associated with variation in fruit production and seedling recruitment. N. mezcalaensis yielded the highest mean due to its high fecundity in 2001–2002. This result suggests that the variation in demographic behaviour observed between species is sufficient to explain the higher abundance of N. mezcalaensis compared to the rare N. macrocephala. The high fecundity values and recruitment success observed in the former, even if they occur only seldom, may result in higher average values accounting for its high population densities.     

Importanza Dei Fattori Ambientali E Genetici Sul Contenuto Alcaloideo Di Atropa Belladonna

Abstract

A research has been carried on to investigate the possible cause for the remarkable atropine content shown by two samples of Atropa belladonna L., one from the upper Metauro valley (AM) and the other from the National Park of Abruzzo (PNA) (Quilici, 1958).

For this purpose the plants were cultivated in a sperimental garden at 1600 m. on the Appennines.

At the end of the cultivation a further considerable increase of alkaloids was found (AM = 1,23%; PNA = 0,98%).

These contents in total alkaloids are quite unknown for the Italian Belladonna, and exceptional even in other countries.

A genetical phenomenon is possibly involved and several authors are inclined to consider well established the occurrence of «chemical races», among spontaneous plants (Bezanger-Beauquesne, 1958).

It is therefore of interest to analyse as many plants as possible collected in several places to isolate the richest in alkaloids and which can be used with profit for cultivation and hybridation.

In this work three other data on Italian Belladonna are listed. The plants analysed were collected in the Botanical Gardens at Siena and at Perugia.

The two samples of Siena were very luxuriant and showed high alkaloid percentages (0,8% and 0,53%), the sample collected at Perugia was much smaller and less rich in atropine (0,42%). It is rather difficult to establish which cause might have increased the alkaloid contents of these plants, but, without exclusion of a possible influence of some external factors, it is likely that the chromosomic set of these plants has undergone some change in consequence of several past hybridations. Further research on this subject is at study.