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1.
Abstract

Air-borne pollen census in Messina in the years 1985–1986 - Pollen of 20 herbs and weeds, and that of 14 trees or shrubs, were identified in the air of Messina (Southern Italy), in the years 1985–1986. The relative frequencies were correlated with climatic factors affecting the pollen diffusion in the studied area.  相似文献   

2.
Abstract

Ultrastructure of the apical cell of Halopteris scoparia (L.) Sauvageau (Phaeophyceae, Sphacelariales). - The ultrastructure of resting apical cells of Halopteris scoparia (L.) Sauvageau from material collected in December is described. The cytoplasm is higly vacuolated with lipids, poliphenolic substances and polisaccharides occurring inside the vacuoles (the classic « physodes »).

Two cell organelles are prominently active at this stage: conspicuosly hypertrophic dictyosomes and the budding endoplasmic reticulum. Both light and electron microscope observations show that the cell wall has an outer stratification and inner discontinuous thickenings, the constituent material of which is uniformerly dispersed.

The above observations point out that the apical cell of Halopteris scoparia at this stage of its life cycle is engaged in an elaboration of vacuolar and parietal substances which will be therefore readly available at the outset of the growing season.  相似文献   

3.
Pollen data collected with a Hirst spore-trap from 1981 to 1988 are presented and related to flora, vegetation and climate of the city of Turin. A comparison of vegetational and aerosporological data collected in other European cities show that, from this point of view, Turin is more similar to the Central-European area than to the Mediterranean one.  相似文献   

4.
Summary Concentrations of airborne pollens recorded in Trieste in 1989 are evaluated in relation to allergic complaints in 113 patients with skin prick tests positive to one pollen species. Analysis of the result enable the two most important allergens to be confirmed as: Poaceae in 70.7% of patients and Parietaria in 18.6%. Few people had monosensitation to Compositae (Artemisia), Corylaceae and Fagaceae.Sympotoms are related to the flowering period when pollen levels climbed to daily averages of 15–20 grains/m3 but they started later than airborne peak concentrations and finished later than pollen decline. Pollen concentration recording can be a useful way to predict the clinical manifestation in sensitive patients but other factors are involved in determining symptoms like subjective mucosal reactions, polysensitization, patients living and working environment.  相似文献   

5.
Many seasonal respiratory allergies are caused byairborne pollens. There is an evident correlationbetween allergic attacks and the amount of pollens inthe atmosphere at any time. The airbornetree pollen concentration and the relevantrepercussions on pollinotics hasnot yet been extensively reported for all Italian regions.We present the results of a 3-year, weekly, tree pollen count byBurkard spore trap from the atmosphere of Parma,Italy. Annual pollen calendars were made from theresults. The study has been conducted because, in Europe,an increasing frequency of allergic sensitisation to thesepollens has been observed.  相似文献   

6.
Abstract

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

7.
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.  相似文献   

8.
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.  相似文献   

9.
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.  相似文献   

10.
11.
12.
An explosion set off in a limestone quarry located in the surroundings of Rapino (Chieti, central Italy), in the National Park of the Maiella Massif, exposed a small cave containing a Late Pleistocene fauna and Mousterian tools. Amongst the specimens is a fairly well preserved dorsal portion of a left mandibular corpus with associated M1 and M2 attributable to Macaca. The Grotta degli Orsi Volanti specimen is the very first macaque ever found in Abruzzo, but it also is one of the most recent, and the southern and easternmost known from Italy.  相似文献   

13.
In this paper cremated human remains from an urn field dating from the final phase of the Bronze age (Guidonia, Rome, Central Italy) were studied. The aim of this study was to identify the minimal number of individuals for grave and cremation patterns. The results show as the ways in which the cremations were carried out were archaic in all the elements that made them up.  相似文献   

14.
This paper presents atmospheric pollen concentrations of fifteen entomophilous trees of Eastern India. The period of anthesis and anther dehiscence varied from morning to evening. Insects and other flower visitors were found to accelerate the mechanism of pollen dispersal. The highest pollen concentration was for 267/m3 in Aegle marmelos followed in decreasing order by Eucalyptus globosus (207/m3), Cassia siamea (186/m3), C. fistula (180/m3), Delonix regia (171/m3), Butea monosperma (159/m3), Bombax ceiba (156/m3), Tectona grandis (144/m3), Terminalia arjuna (138/m3), Moringa oleifera (126/m3), Anthocephalus chinensis (114/m3), Syzygium cumini (96/m3), Dillenia indica (30/m3), Syzygium jambos (27/m3), and Kleinhovia hospita (2/m3).  相似文献   

15.
Aerobiological data of pollen emission concentrations is used to predict fruit production. The principal aim of this work was to study the relationship between pollen emission patterns, emission homogeneity and fruit production in olive (Olea europaea L.). Data of daily pollen concentrations in the atmosphere during the flowering period, collected over a 20‐year period in Perugia (Central Italy), and the corresponding fruit production data were analysed. Correlation and regression analyses on the partial pollen amounts (subdivisions of the whole flowering period), their statistical variability (expressed as coefficients of variation of the daily pollen concentration), and the production values in the different years demonstrate that pollen emission, during the seven to ten day period immediately preceding the maximum pollen emission day, appears to be most closely related to fruit production. Moreover, the pollen emission homogeneity (minimal variability in daily pollen concentrations) during the “critical” flowering period is very important for fertilization.  相似文献   

16.
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.  相似文献   

17.
DNA barcoding may be particularly important in influencing ecology, economic issues, and the fundamental crisis facing biodiversity as a standardized, species-level identification tool for taxonomy assessment. Trees play important roles in the conservation of many land ecosystems, the wood trade, and the definition of biogeographical processes; nevertheless, peculiar biological, evolutionary and taxonomical features will probably constitute an intriguing challenge to barcoders. We examined whether four marker regions (trnh-psba, rbcL, rpoc1, matK) proposed by the Consortium for the Barcode of Life (CBOL) matched species taxonomy in a preliminary tree biodiversity survey of Italian forested land. Our objective was to provide a test of future in situ applications of DNA barcodes by evaluating the efficacy of species discrimination under the criteria of uniformity of methods and natural co-occurrence of the species in the main forest ecosystems. Fifty-two species were included in a floristic study. We obtained 73% total discrimination success, with trnH-psbA as the best performing marker and oaks as the least responsive plants to the markers used. A further taxon-based study of Quercus (thirty specimens, 12 species) revealed that this genus is refractory to barcoding (0% discrimination success), a probable consequence of low variation rate at the plastid genome level, hybridization, and the incidence of biogeography. We conclude that some species-rich tree genera in small geographical regions may prove exceptionally difficult to barcode. Until more efficient markers are developed, we recommend that improved and diversified sampling (multiple locations of sympatric and co-occurring congenerics) be embraced as a timely and important goal for the precise assessment of haplotype specificity to facilitate the productive application of barcoding in practice.  相似文献   

18.
S. Cocucci  E. Marrè 《Plant biosystems》2013,147(3-4):340-344
Abstract

On the effect of dinitrophenol on carbohydrate activation in higher plant tissues. — Previous investigations on the effects of 2,4 dinitrophenol (DNP) on carbohydrate metabolism in isolated pea internodes and in yeast showed that the increased rate of glycolysis induced by the uncoupler corresponds to an increased rate of the conversion of free hexoses and polysaccarides to hexose phosphates. In yeast about 30% of the radioactivity supplied and taken up as 14C labelled glucose, and 20% of that supplied and taken up as glycerol is recovered as soluble sugar and glycogen; this phenomenon is almost completely suppressed by 10-4M DNP.

This suggested that a mechanism involving kinase enzymes, on one hand, and phosphatases, on the other, is mediating the interconversion of phosphorylathed and free sugars, and that the apparent increase of hexose phosphorylation observed in the presence of DNP might depend on a decreased rate of phosphatase mediate reactions, consequent to the decrease of phosphorylated sugars level in the cell.

The experiments here reported were planned to test the validity of this hypothesis in the case of higher plant tissues.

Material used in these experiments were segments from the growing part of the third internode isolated from 7 day old, etiolated pea seedlings, and carrot root diks (0,7 mm thick, 7 mm diameter) preincubated for 24 hours in aerated distilled water. Both of these materials show an active, steady respiration and some growth activity, so that they may be taken as representing a condition close enough to that of the generally physiologically active higher plant tissues.

The reversibility of the hexose phosphate-free sugar interconversion process was tested by feeding 10-3M 1-C14 labeled glycerol, and measuring after 150 minutes the amount of radioactivity incorporated into CO2, soluble sugars, organic acids and proteins. The results of these experiments are summarized in table I and II.

Glycerol metabolism as well as its response to DNP appears very similar in the two material used. In both cases, glycerol uptake and incorporation into organic acids and amino acids is almost insensitive to DNP. In contrast large differences are observed for the free sugar fraction. In the absence of the uncoupler, a consistent amount of the radioactivity fed as glycerol is found in this fraction. It appears reasonable to assume that the glycerol-sugar interconversion comprehends, as intermediate steps, glycerol-P, fructose di-P (or sedoeptulose di-P) and hexose-6-P. If this is true, the observed data implicate that a continuous interconversion occurs, in the cell, between sugar phosphates and free sugars and vice-versa, one reaction direction involving the activity of phosphatases, and the other one that of kinases. The true rate of this interconversion process is probably much larger than indicated by the radioactivity found in free sugars: as a considerable part of the triose-P transormed into sugars must immediately re-enter the descending flux of glycolysis.

This view finds some support in the fact that DNP almost completely inhibits the incorporation of radioactivity in the free sugar fraction. It has been previously observed that DNP very markedly decreases the level of hexose mono- and di-phosphates and of triose-phosphates in the pea stem tissues. If phosphatases acting on fructose di-phosphate and on hexose-6-P are not saturated by their substrates, a decrease of the rate of free hexose synthesis from sugar phosphates should be expected.

The present results are thus consistent with the hypothesis that hexose phosphates and free sugars in the cell are continuously interconverted by the simultaneous action of phosphatases and kinases; and that the effect of DNP, and thus of any physiological conditions decreasing the ATP/ADP ratio in accelerating free hexose utilizations is at least in part due to a decreased rate of the reactions catalized by fructose diphosphate and hexose-6-P phosphatases. The reversibility of the kinase-phosphatase system would thus represent a crucial link in the mechanism by which the rate of carbohydrate activation and breackdown is controlled by the rate of utilization of high-energy phosphate bonds.  相似文献   

19.
Modern pollen assemblages as climate indicators in southern Europe   总被引:1,自引:0,他引:1  
Aim and Location Our aim is to develop pollen–climate inference models for southern Europe and to test their performance and inference power by cross‐validation with modern climate data. Surface sediments collected from lakes along a climate gradient from the winter‐cold/summer‐wet Alps to winter‐wet/summer‐dry Sicily were analysed for modern pollen assemblages. Methods For each lake, mean monthly temperatures, seasonal precipitation and site‐specific climate uncertainties have been estimated. Pollen–climate relationships were studied using numerical analyses, and inference models were derived by partial least squares (PLS) and weighted‐averaging PLS (WA‐PLS) regressions for January and July temperatures (T), and for winter, spring and summer precipitation (P). In order to assess whether these variables are also of ecological importance for vegetation in the subregions, we split the data set into an Alpine and a Mediterranean subset. Results Low bootstrap cross‐validated root mean square errors of prediction (RMSEP) for January T (1.7 °C), July T (2.1 °C) and summer P (38 mm), as well as low RMSEPs expressed as a percentage of the gradient length (8–9%), indicate a good inference power. Models revealed excellent to good performance statistics for January T, July T and summer P (r2= 0.8), and for winter and spring P (r2=c. 0.5). We show that the variables with the highest explanatory power differ between the two subregions. These are summer T and P for the Alpine set, and January T, winter P and July T for the Mediterranean set. Main conclusions The study reveals the influence of climatic conditions during the growing season on modern pollen assemblages and indicates the potential of pollen data for long‐term climate reconstructions of parameters such as winter precipitation and temperature, which seem to be the main factors having an influence on the variability of Mediterranean climate. These models may therefore provide important information on past regional climate variability in southern Europe.  相似文献   

20.
The results of phenological observations in ageomorphologically differentiated area are shown.Phenological surveys were conducted on flowering andpollen emission of some common and widely diffusedGraminaceae species, using a 7-step key. By means ofmultiple regression analysis altitude,latitude, slope and exposure were identified as significantenvironmental factors in giving rise to thepollination: in particular with respect to altitude thephenological pattern showed a negative gradient below100 m of altitude and a positive one above.  相似文献   

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