Michele Scotton

Additional file 4:Complete list of Fusarium oxysporum f. sp. melonis(FOM) transcripts identified by cDNA-AFLP analysis from fungal samples of colonies grown in vitro and selected for sequencing. TDFs were chosen on the basis of their differential abundance in the different FOM strains. Identification numbers (ID) correspond to the progressive numbering of bands in the gels. The primer combination used to visualize each band (Bst-Mse column) and the corresponding length of the fragment are reported, along with the accession number retrieved from the database and the corresponding blast score and annotation. In addition, the file reports the presence (+) or absence (-) of expression of each transcript for the 3 strains of FOM. (XLS 34 KB)

Additional file 1:Complete list of melon genes modulated by infection with avirulent (ISPaVe1070 race1) or virulent (ISPaVe1018 and ISPaVe1083 strains of race 1,2) strains of Fusarium oxysporum f. sp. melonis, organized by clusters as defined in the results section. Identification numbers (ID) correspond to the progressive numbering of bands in the gels. The primer combination used to visualize each band (Bst-Mse column) and the corresponding length of the fragment are reported, along with the accession number retrieved from the Melon Unigene or Uniprot database, the annotation, the corresponding blast score, and the functional category to which each transcript was assigned. In addition, the file reports the expression profile of each transcript, estimated on the basis of the band intensity with a score ranging from -3 to 3, in comparison to the corresponding band in the mock-inoculated controls. (XLS 184 KB)

Additional file 5:List of primers used in Real time RT-PCR analysis. Identification numbers (ID) correspond to the progressive numbering of bands in the gels. The accession codes for each gene represent the corresponding database in which homology was identified, MU = Melon Unigene, FOX = Fusarium Comparative Database. (XLS 24 KB)

Additional file 3:List of the core 54 melon genes, which remain modulated in a coherent way (induced or repressed) throughout the experiment (from 4 dpi onwards) in the incompatible interaction between melon and the FOM race 1 strain ISPaVe1070. (XLS 38 KB)

Plant biodiversity is an important feature of grassland ecosystems, as it is related to the provision of many ecosystem services crucial for the human economy and well-being. Given the importance of grasslands, research has been carried out in recent years on the potential to monitor them with novel remote sensing techniques. In this study, the optical diversity (also called spectral diversity) approach was adopted to check the potential of using high-resolution hyperspectral images to estimate α-diversity in grassland ecosystems. In 2018 and 2019, grassland species composition was surveyed and canopy hyperspectral data were acquired at two grassland sites: Monte Bondone (IT-MBo; species-rich semi-natural grasslands) and an experimental farm of the University of Padova, Legnaro, Padua, Italy (IT-PD; artificially established grassland plots with a species-poor mixture). The relationship between biodiversity (species richness, Shannon’s, species evenness, and Simpson’s indices) and op...

ABSTRACT Wild harvesting is an efficient option for supplying seed to be used for restoring seminatural grasslands. Several methods are currently used to implement wild harvesting, but few controlled experiments have investigated its efficiency regarding seed amount and number of species collected. A harvesting trial was conducted in a species-rich, low-productivity grassland of the calcareous Italian Alps (1 030 m above sea level [a.s.l.). Three mechanical methods were tested in three replications using a completely randomized block design: green hay (GH), dry hay (DH), and seed stripping (SS) harvesting. The number of fertile shoots, mature seeds, and species collected was recorded and compared with the standing seed yield (SSY). GH, DH, and SS harvested approximately 84%, 70%, and 29% of SSY, respectively. Forbs were harvested more efficiently than grasses in all methods but in most cases at very low seed amounts per m2 due to their low seed density for SSY. No significant difference among methods was found for the number of species collected as mature seeds, but SS, implemented on larger plots, tended to collect more forb species. Comparing the results with those of other experiments demonstrated that the relatively cool temperature of the seed maturation period at the mountain site favored stronger seed retention and therefore increased the GH and DH efficiency but decreased the SS efficiency. In cool mountain areas, wild harvesting from forb-rich grasslands should bemore successful by SS implemented on wide areas and several times over the vegetative season. In less species-rich grassland, GH and DH can efficiently collect high seed amounts of the fewer species present, even if implemented over smaller areas.

FDC 235.42 : (450.34) Questo studio analizza i rinverdimenti eseguiti sulla frana storica di Valmorel (900 m s.l.m. circa: BL) realizzati negli anni dal 1950 al 1970 con metodi diversi da quelli oggi normalmente in uso e cioe senza consistenti rimodellamenti del suolo, conservando le isole di vegetazione residua e utilizzando solo materiale vegetale nativo. Per il quarantennio ’54-’91 e stata analizzata, mediante l’interpretazione di foto aeree, l’evoluzione della copertura vegetale, evidenziando l’importante ruolo della rivegetazione spontanea. La dinamica vegetazionale in atto e stata valutata sulla base di rilievi floristici eseguiti con metodo fitosociologico. Sono stati, inoltre, definiti Indici di naturalita delle specie e delle fitocenosi, utili per valutare la naturalita delle vegetazioni costituite tramite il rinverdimento. Con tali indici i rinverdimenti di Valmorel sono stati confrontati con rinverdimenti trentini recenti, evidenziando, per questi ultimi, valori di natura...

The increasing anthropisation of mountain regions is a cause of soil degradation, which needs to be addressed. Conventional methods of ski slope revegetation often fail to stabilise the soil and recover natural vegetation. To test alternative methods to create a persistent, biodiversity-friendly plant cover, different sowing (site-adapted native propagation materials vs. forage cultivars vs. no sowing) and fertilisation treatments were compared over nine years at a graded ski slope. Because of the gravelly soil, the ninth-year plant cover was only 65%, which was sufficient to prevent erosion. All native propagation materials were equally efficient at recreating a semi-natural grassland. Except for Festuca rubra, the forage cultivars did not persist. However, native volunteer species from close natural ecosystems efficiently colonised plots sown with forage cultivars and plots that were not sown. This resulted in a lower plant cover but a high similarity to the surrounding vegetation...

Studying the effects of fertilisation on the seed production of grassland species can help understand the vegetation changes and biodiversity losses due to soil eutrophication. The seed production of fifteen grasses and seventeen forbs from a temperate hay meadow was studied under three fertilisation treatments: 0-0-0, 0-54-108 and 192-108-216 kg N, P2O5 and K2O respectively, per year. Fertile shoots collected at the seed maturation stage were analysed for all main traits of the gamic reproduction. On average, forbs produced more ovules and viable seeds per shoot (199 and 65, respectively) than grasses (112 and 35, respectively). Fertilisation increased the number of inflorescences per shoot in both grasses and forbs and had a limited but variable effect on germinability and viability in the two functional groups: viability increased in grasses but often decreased in forbs. This pattern resulted in 55% and 11% increases in viable seed production in grasses and forbs, respectively. A...

A diverse collection of Juglans species and hybrids with potential to serve as walnut rootstocks was evaluated to identify resistance to Phytophthora cinnamomi, a destructive pathogen affecting commercial production of Persian walnuts worldwide. A total of 35 Juglans genotypes, comprising hybrids and Juglans microcarpa, plus three Juglans regia genotypes as comparison, were inoculated during two seasons (spring and autumn) for 3 years, with two isolates of P. cinnamomi. Inoculations were carried out on excised shoots of the different genotypes by replacing a bark disk with a P. cinnamomi culture plug. After incubation, necrosis length caused by the pathogen was measured. Data were collected and statistically analyzed with generalized linear mixed models. This work pointed out a seasonal influence on some Juglans genotype response to P. cinnamomi: both hybrids and J. microcarpa groups were significantly less sensitive in autumn compared with spring (P = 0.0006), thus this condition m...

Abstract Establishing semi-natural grasslands by using seeds from wild harvesting is an effective method to restore vegetation with high natural value. However, studies implementing this strategy for the revegetation of coarse soils are scarce. In this study, different types of propagation material (green hay, dry hay, and hay-flower from seed stripping) harvested at a species-rich European vegetation typical for calcareous soils (Mesobromion) were used at different sowing densities (range, 450–3000 seeds per m2) to restore a very unfertile soil consisting of coarse wastes from a calcareous quarry. The experiment, organised in a randomised block design with three replicates, was established in 2009, and the species composition and structure were surveyed over five years. The threshold of 70% vegetation cover effective against erosion was achieved within two years after sowing. Neither the type of propagation material nor the sowing density influenced the number of species transferred or the final vegetation cover. However, seed density affected the time of achieving the 70% threshold of plant cover important for erosion control (two or three years after sowing depending on the seed density). Of the seventy-three donor site species, fifty-nine were recorded at least during one year on the restored site (absolute transfer rate of 81%), but only forty-six were recorded in the last year (final transfer rate of 63%). Vegetation development was characterised by loss or decrease of donor site species not well adapted to grow in nutrient-poor soils and increase by species typical for coarse textured soils. The very low soil nitrogen content caused an abundance of nitrogen-fixing species (legumes) compared with that at the donor site. Restoring very coarse calcareous quarry wastes, even without soil improvement, is possible provided the climatic conditions are favourable and seeds of good quality are available.

Livestock farming in large-scale pasture landscapes can fulfil the economic and ecological requirements for sustainable, biodiversity-friendly agriculture of the European Union (EU). However, little is known about the grazing systems that have maintained these pastures for centuries. The traditional grazing methods and their effects on the cattle behaviour were therefore studied at 23 mountain summer farms in the Asiago upland (northeastern Italy). Traditional methods of free-ranging and herding were the only techniques adopted by farmers. Only environmental factors (size and perimeter length of the pastoral unit) were significantly associated with the grazing method used. Free-ranging was more often performed in small and homogeneous farms, while herding was done in large and heterogeneous farms. Herding led to a more homogeneous grazer distribution and better regulated the lengths of the cattle daily routes than free-ranging. The grazing direction and resting sites were almost exclusively affected by environmental factors. Cattle grazed predominantly in the direction from which the wind was blowing, and preferred resting at windy sites in the daytime (escaping from flies) and at open areas close to woods during the night (being protected against cold winds). Other traits shared between free-ranging and herding were: the seasonal organisation of grazing into periods and camps; re-grazing of the same surface within a few days; everyday use of different pasture types; and rhythms in the cattle daily activities. Even if they may have lower productivity compared to rotational stocking, the studied traditional grazing methods, especially herding, have the advantages of respecting spontaneous cattle behaviour, producing more savoury cheeses, and better maintaining heterogeneous and biodiversity-rich landscapes. More attention should be paid to traditional grazing methods within measures aiming to conserve cultural heritage and agricultural biodiversity.

Abstract Forbs are important biodiversity components of grasslands and are often threatened by management intensification. As most forbs propagate predominantly by seed, knowledge of their seed regenerative traits would improve the conservation and restoration of forb-rich ecosystems. The main seed production traits of six forbs that are common in European species-rich grasslands were studied by collecting fertile shoots from different sites and over several years. Among sites and years, variability was high, particularly in the number of inflorescences per shoot, which affected ovule production more than any other trait. Relationships between inflorescence size and the number of ovules were mainly negatively allometric or almost so, with lower flower densities in larger inflorescences. The average ovule-to-seed transformation efficiency was 58%. There was significant variation among collections of the same species, and even more between species. Species with a low ovule-to-seed transformation efficiency generally exhibited compensatory, high seed viability. Large inflorescences had high ovule to seed utilization values, probably because of better nutrient conditions. Seed germinability (average, 30%) was much lower than seed viability (average, 54%); therefore, seed dormancy was an important feature of the species studied.

Semi-natural grasslands are of great importance to European biodiversity. Their restoration in mountain regions often presents specific problems of raw soil stabilisation and difficult climatic conditions. Methods used to tackle these problems include increasing sowing density and fertilisation. However, past studies were performed at only one site or for a short time and do not clearly show how site traits and time affect restoration results. In six field experiments undertaken on raw soils in the Italian Alps, the effects of sowing density, fertilisation, soil, and climate on the development over time of plant density and cover were analysed over three to six years. The seed was collected from nearby grasslands and sown at rates of 335-21,410 seeds m-2. During the first one-two years, the percentage of seeds producing established plants at low seed rates was higher in stonier surfaces; however, at high rates a larger absolute plant number was recorded in finer soils. Two to five years after sowing, climatic conditions became more important. Full vegetation cover was achieved in all experiments. However, at high altitudes, individual plant cover became greater (and plant density decreased), probably because the grasses needed to accumulate more non-structural carbohydrates necessary to survive during the longer winter. Fertilisation accelerated the establishment of full vegetation cover by 1 to 3 years as it increased the mean cover per plant without affecting plant density. Grassland restoration is possible in mountain raw soils by using the seeds collected from nearby donor sites. High sowing densities are not required even in coarse or higher altitude soils because, in the short term, stones on the ground surface increase the percentage of seed producing established plants and, over the long term, plant density is not dependent on the sowing density. In low-fertile soils, fertilisation accelerates the establishment of full vegetation cover.

Abstract Due to their low elevation range, coastal environments are extremely sensitive to rising sea levels resulting from climate change and other direct human impacts. Increased knowledge about site and vegetation characteristics can contribute to improving their conservation and restoration. A survey of 51 sampling areas and seven transects in the sand dune, salt marsh system of Vallevecchia (Caorle, Italy) was conducted, while taking into account the vegetation and certain important topographical, soil, and hydrological characteristics. The most important factors differentiating the presence of sand dunes and salt marsh vegetation were found to be soil electric conductivity (EC: threshold EC = 0.4 mS cm −1 ) and site elevation (threshold + 0.70 cm a.s.l.). In psammophilous vegetation, the soil pH and EC decreased with elevation and the water table was composed of freshwater. A small amount of salt accumulation was found only at the white dune bottom. In salt marsh vegetation, the soils were flooded daily by high tides and were saline and alkaline at higher elevations, where less frequent tide flooding led to frequent soil drying and salt accumulation. The soil OM content of the salt marshes was highest due to the slow mineralization rate as a consequence of the high water content. The current low sediment transport from adjacent rivers was the cause of the regression of the central-eastern part of Vallevecchia, where the dunal system width and number of vegetation types decreased and the height and mean slope of the sea facing sides of the white dunes increased. The 60-cm local sea level rise predicted by 2100 will increase the salt marsh extent by 60%, which will be a disadvantage for the more rare non-saline retrodunal and psammophilous vegetation. Reactivating river sediment transport, reducing or eliminating the deep-rooted pine and Ammophila arenaria plantations and closing drainage ditches in the adjacent pinewoods can mitigate the negative impacts of sea level rise.

Maintaining and re-creating species-rich semi-natural grasslands are important issues in current agricultural policy in Europe. The seed that is required for their establishment can be obtained through direct harvesting from semi-natural herbaceous vegetation. To test the efficiency of mechanical seed harvesting on donor Arrhenatherion elatioris grasslands, experiments were performed in northern Italy and eastern Czech Republic. Trials were organized with a randomized block design and involved harvesting as green hay (grass mowing and immediate collection), dry hay (grass mowing and collection after drying on the field), direct combining (grass cutting and threshing at the same combine passage) and seed stripping with pull-type equipment (seed removal without grass cutting with a brush harvester pulled by a tractor). Harvesting was carried out at the time of maximum ripe standing seed yield (SSY) in the first and second regrowth. The harvested materials were analysed for seed number and weight and compared with the SSY. The species composition and phenology were also surveyed. In all methods, the seed mixture obtained contained the species present as seed at harvest time and was correlated with SSY. However, with regard to the seed number collected, the harvesting efficiency changed in relation to species group (grasses or forbs), individual species, seed maturation and regrowth. The most efficient method was harvesting as green hay (efficiency of approximately 71% of SSY and seed mixture composition that was very highly correlated with SSY). The least efficient methods were direct combining (30% of SSY and negative selectivity against light or difficult to detach seeds, producing the highest mean 1000-seeds weight) and harvesting as dry hay (39% of SSY and a high sensitivity to seed maturation level). Seed stripping, operated with downward brush rotation at the leading edge, resulted in an intermediate efficiency (60% of SSY and a seed mixture composition highly correlated with SSY). The harvesting efficiency for seed number was higher at the first regrowth than the second one for both species groups and, especially at the second regrowth, higher for forbs than for grasses. Especially forb harvesting presented a problem with regard to the species number collected. The problem was, not due to harvesting inefficiency but rather for phenological reasons, as several forbs did not produce fertile stems at the first or second regrowth and some other early flowering species had already shed the seed at the harvesting time. These results improve our understanding of factors affecting the efficiency of mechanical harvesting and will help in the preparation of efficient harvesting programs.

This work is part of a comprehensive study addressed to gain new insights into Fusarium oxysporum f. sp. melonis (FOM)-melon interaction and understand molecular mechanisms of disease control by grafting. Grafting vegetable is primarily used to provide resistance to soilborne diseases. In this study, the effect on FOM race 1 and race 1,2 gene expression was investigated by quantitative PCR (qPCR), during infection of both resistant and susceptible grafted melon scion-rootstock combinations. Eleven fungal genes related to pathogenicity were considered. The expression of the selected genes varied according to race, susceptible or resistant interaction, and time clustering into six profiles. Classical infection related genes, including Zn-Cys transcription factor FOW2, xylanase, and its relative transcriptional activator were highly induced particularly in the resistant combination when infected by race 1,2 at any time point. In turn, ROS degrading catalase/peroxidase enzyme and actin binding protein were upregulated only at the early stage of infection, in both resistant and susceptible combinations. Genes such as E3 ubiquitin-protein ligase and UTP-glucose-1-phosphate uridylyl transferase showed significant differences between both FOM races in both grafting combinations. Whereas MADS-box transcription factor and acyl-CoA synthetase were essentially unmodulated in race 1, but induced in race 1,2. The only gene significantly dependent on fungal race, resistant/susceptible interaction, and time, was a histidine kinase. Temporal transcription profiles were consistent with the capacity of race 1,2 to grow in the resistant host without inducing wilting symptoms being race 1,2 host colonization independent from virulence. In general, single FOM gene transcription profiles showed no evident differences between rootstock and scion confirming at a molecular level that a melon grafted plant reacts to the pathogen as a single genotype ruled by the rootstock.

Abstract Species-rich semi-natural grasslands play an essential role in the conservation of European biodiversity. To restore them, existing grasslands may be used as a seed source. A key factor for successful restoration is the transfer of all species of the plant community to the site being restored. This approach, however, often poses practical problems due to variations in species phenology, so that only time-staggered harvesting allows the seeds of many species to be collected. Poor harvesting methods may reduce the number of species transferred from the donor to recipient site. The effects of harvesting at various time points by various methods were evaluated here in a restoration experiment on an ex-arable field in Northern Italy. Propagation materials from the first or second regrowth (or both) of a meadow dominated by Arrhenatherum elatius were collected by four harvesting methods. The materials were spread at the sowing density between 830 and 14360 seeds m −2 . Species composition and structure of the vegetation were examined during 6 years. Untransferred species were almost exclusively those not present at harvesting as mature seed. Compared with materials from one regrowth period, materials from both regrowth periods significantly increased the number of transferred species per plot (26.5 vs. 28.5, respectively) and the absolute transfer rate (64% vs. 75%). Higher sowing density yielded a greater number of positive than negative effects. It favored stable establishment of donor site species and significantly reduced the presence of weeds. Nonetheless, due to the initial dominance of species with high sowing density, evenness of the restored plots was lower than that at the donor site but increased with time, at least under low- and medium-sowing-density conditions. Multiple harvesting at time points when several species with mature seed are present increases the species transfer rate. Medium sowing density positively affects restoration development because it promotes the establishment of donor site species with lower sowing density, prevents species with the highest density from dominating the vegetation during the first few years, and reduces weed cover.

ABSTRACT Semi-natural Alpine grasslands represent an important Western European ecosystem but recent agricultural intensification has substantially changed their characteristics. The extent to which this ecosystem may have been compromised are quantified using a combination of farm, soil and botanical attributes collected for 48 hay-meadows over 2 years in the Non Valley (Eastern Italian Alps). Due to the wide range of estimated nutrient balances meadow type diversity is high but the trend is for the creation of productive but species-poor meadows at the expense of low-intensity but species diverse ones. Currently the typical Arrhenatherum elatius grasslands are less species-rich and Bromus erectus ones, traditionally not fertilized, are now often subject to low fertilisation. Yields can be high (up to 10.5 t d.m. ha−1 year−1 at about 1000 m a.s.l.) but, due to the generally late first cut and low cutting frequency, these provided reduced forage quality sometimes accompanied by excessively high potassium concentrations. Forage quality is not generally sufficient for highly productive dairy cattle, so that supplementary feeding is required. Reduced cutting frequency and traditional hay-making also limit the efficient removal of nutrient inputs with annual surpluses up to 245, 63 and 293 kg ha−1 for N, P and K respectively. The combination of sandy soil texture and sloping ground do not favour nutrient retention therefore increasing the potential risk for the wider environment. Reducing the trend of genetic cattle improvement towards high milk production and replacement of the traditional Brown Swiss breed with Friesian Holstein, more efficient forage harvesting and higher cutting frequency could greatly improve the environmental sustainability of new meadow types. However, biodiversity conservation can only be achieved if enough of the extensive grassland is maintained coupled with appropriate management of intensive meadows.

Quantitative characteristics of yield of Lucerne (Medicago sativa L.) rotate meadows could be affect by various factors, of which the most important are: environment of meadow location, fertilization (amount and kind of nutrients), irrigation, climatic conditions, harvest period, vegetative stage and also the cultivar used (Parrini e Bonari, 2002).With the aim to contribute to define the effect of the last factor mentioned on the qualitative characteristics of the Lucerne yield, a plot trial was carried out for two years where 15 cultivars of Lucerne and.......

– To contribute to the sustainability definition of the extensive sheep production systems, traditionally adopted in protected areas of Central Apennines, the work was aimed at assessing the pastoral value of the pastures (1400-2450 m a.s.l) of Monti Sibillini National Park. Eighty-one vegetation surveys were performed during two consecutive summers on an area of about 300 ha. The vegetation data were analysed by means of cluster analysis methods. Based on the Specific Indexes (scale 0-5) of the plants, the Pastoral Value (0-100) of the pastures was calculated, on which the potential stocking rate assessment should be based. The vegetation analysis led to the definition of 12 pasture types characterised by different species composition. Festuco-Seslerietea, Festuco-Brometea, Molinio-Arrhenatheretea and Nardo-Callunetea were the most frequent phytosociological classes. The assessment of the pastoral value showed values varying between 18.6 and 35.8 for the Sesleria nitida-and Carex m...

– In order to identify negative aspects connected with the extensive grazing management actually adopted in Italian protected areas, the forage selection by sheep on the plants and pastures (1500-2450 m a.s.l.) in the Monti Sibillini National Park is described and discussed. 81 surveys, performed on 12 different pasture types showed a high forage selection both on the plants and on their parts. Based on direct observations of the animal movements and grazing management, a selective behaviour was also observed on the pasture types. In fact, because of the low stocking rates [globally around 0.38 Standard Livestock Units (SLU)/ha] and of a limited presence of shepherds, the sheep could select the forage and therefore prefer the pastures with higher pastoral values. RESUME – "Sélection du fourrage par les moutons dans les systèmes de pâturage extensif dans le parc national des "Monti Sibillini" (Apennin Central, Italie)". Afin d'observer les aspects négatifs lié...

Semi-natural Alpine grasslands represent an important Western European ecosystem but recent agricultural intensification has substantially changed their characteristics. The extent to which this ecosystem may have been compromised are quantified using a combination of farm, soil and botanical attributes collected for 48 hay-meadows over 2 years in the Non Valley (Eastern Italian Alps). Due to the wide range of estimated nutrient balances meadow type diversity is high but the trend is for the creation of productive but species-poor meadows at the expense of low-intensity but species diverse ones. Currently the typical Arrhenatherum elatius grasslands are less species-rich and Bromus erectus ones, traditionally not fertilized, are now often subject to low fertilisation. Yields can be high (up to 10.5 t d.m. ha−1 year−1 at about 1000 m a.s.l.) but, due to the generally late first cut and low cutting frequency, these provided reduced forage quality sometimes accompanied by excessively h...

RIASSUNTO – Primi risultati sull'effetto di differenti date di inizio pascolamento sulla produzione di un pascolo polifita della pianura veneta – Le recenti misure agro-ambientali della Comunità Europea sostengono l'adozione di pratiche agricole a basso impatto ambientale. Nella pianura veneta, si è studia-to l'effetto della data di inizio pascolamento (precoce o tardiva) sulla quantità e qualità dell'erba di un pascolo a rotazione senza fertilizzazione e irrigazione. La produzione di sostanza secca del pascolo nelle due tesi è stata simile, ma nella tesi a inizio precoce la distribuzione del foraggio durante la stagione è stata più uniforme, con meno sprechi a primavera e più produzione in autunno rispetto alla tesi ad inizio tardivo. L'inizio di pascolamento precoce ha migliorato la qualità del foraggio nelle prime due rotazioni primaverili mentre, dopo lo sfalcio primaverile di pulizia, le caratteristiche qualitative del foraggio sono state simili nelle due te...

SUMMARY - In order to contribute to a better understanding of the excrement distribution on mountain pastures by grazing animals, at the end of the grazing season of 1996 the faeces concentration was assessed in a rotational grazing experiment, conducted for six years on a natural and improved pasture. Five treatments were compared: cattle grazing at low, medium and high stocking rates; and sheep and goats grazing at medium stocking rate. The results showed that, in the low cattle stocking rate treatment, the faeces distribution was proportional to the forage value of the pasture type. On the contrary, in the medium and high cattle stocking rates treatments the faeces distribution was independent of the forage value of the ecofacies. At the medium stocking rate adopted for goats and sheep, the results were similar to the medium cattle stocking rate. The only exception was represented by the sheep grazing on the natural pasture that caused a faeces distribution which was proportional...

A reliable and species-specific real-time quantitative polymerase chain reaction (qPCR) assay was developed for detection of the complex soilborne anamorphic fungus Fusarium oxysporum. The new primer pair, designed on the translation elongation factor 1-α gene with an amplicon of 142 bp, was highly specific to F. oxysporum without cross reactions with other Fusarium spp. The protocol was applied to grafted melon plants for the detection and quantification of F. oxysporum f. sp. melonis, a devastating pathogen of this cucurbit. Grafting technologies are widely used in melon to confer resistance against new virulent races of F. oxysporum f. sp. melonis, while maintaining the properties of valuable commercial varieties. However, the effects on the vascular pathogen colonization have not been fully investigated. Analyses were performed on ‘Charentais-T’ (susceptible) and ‘Nad-1’ (resistant) melon cultivars, both used either as rootstock and scion, and inoculated with F. oxysporum f. sp....

Haymaking and seed-stripping are frequently utilized methods of obtaining seeds for use in ecological restoration. We sought to measure the efficiency of these two techniques in different grassland types in terms of the seed mix obtained compared to the seed present in the vegetation. ...

ABSTRACT Isolations of Gnomonia leptostyla were carried out in 13 plantations of Juglans regia distributed throughout Italy, including Sardinia and Sicily. Mean diameter of colonies grown in vitro at 22°C and sporulation of 191 isolates, grouped by site of collection, were compared. Four groups of isolates, from environmentally diverse sites, were more thoroughly investigated for the effect of temperature (from 10 to 30°C, 5°C increment) on growth and sporulation. Colony growth of isolates within groups correlated with temperature and environmental parameters at the site of collection, such as temperature, rainfall, number of rain days per month and per year, and altitude. Altitude and mean temperature in April correlated with colony growth. In general, the isolates that grew significantly more slowly were from sites with colder early springs and higher altitudes. More significant data were obtained comparing isolates from different sites obtained from the same walnut cultivar or population. The host source was more significantly correlated with colony growth within the same site of collection. Acervular conidiomata were abundantly produced by all isolates at 22°C in darkness after 21 days, while protoperithecia were produced within 2 months by most isolates, under the same conditions. Similarly, the four groups of isolates tested at different temperatures produced conidiomata at 20 and 25°C, but not at 10, 15 and 30°C. After 2 months, protoperithecia were present in most isolates at 20°C, very few at 25 and 15°C, and no production was recorded at 10 and 30°C. Fertile perithecia with asci and ascospores were produced, after 3 months at 10°C in darkness, by six homothallic isolates out of 38 tested. In general, perithecia were larger than protoperithecia both in ascocarp diameter and in neck length. Ascocarp diameter, width of asci and length of ascopores of in vitro-produced perithecia were larger than those of perithecia produced in nature. The latter showed a neck length longer than in vitro-produced perithecia. Virulence of isolates when inoculated on J. regia was correlated with colony growth rate, but rated independently for homothallic or heterothallic isolates. A preliminary screening for sources of resistance to anthracnose in the genus Juglans showed J. sieboldiana and J. cinerea to be highly resistant and both J. nigra and J. hindsii to be highly susceptible to the disease. Juglans regia showed an intermediate response of susceptibility to anthracnose.

We describe natural revegetation dynamics on landslides that occurred in 1948 and 1959 in Franconia Notch, New Hampshire, U.S.A. Analysis of aerial photographs from 1958, 1978, and 1996 indicate that the rate of revegetation of the landslide surface decreased over time, probably because of early saturation of easily colonized sites. In the 1948 landslide, we found that width and slope steepness within the landslide influenced the revegetation rate, while elevation did not. On the 1959 landslide, none of the tested factors were significantly correlated with vegetation recovery. Recolonization of narrow erosional zones tended to occur from the landslide edges inward; recolonization of wider erosional zones also occurred outward from islands of vegetation within the landslide. Floristic inventories were conducted in 1956 and 1996 using the point-centered quarter method and fixed plots of 1 m2 and were processed using cluster analysis, resulting in a grouping of the 1956 and 1996 plots into four and five clusters, respectively. The 1956 clusters consisted of exclusively herbaceous vegetation (zones with greater erosion) or prevalently shrub-arboreal vegetation, with Betula cordifolia Regel. dominant at high elevation and Betula papyrifera Marsh. and Betula alleghaniensis Britton dominant at low to middle elevation. The 1996 vegetation was characterized by prevalence of arboreal canopy made up of differing proportions of birch species, which varied with elevation.Key words: disturbance, floristic composition, regeneration, recolonization, succession, White Mountain National Forest.

Background Fusarium oxysporum f. sp. melonis Snyd. & Hans. (FOM) causes Fusarium wilt, the most important infectious disease of melon (Cucumis melo L.). The four known races of this pathogen can be distinguished only by infection on appropriate cultivars. No molecular tools are available that can discriminate among the races, and the molecular basis of compatibility and disease progression are poorly understood. Resistance to races 1 and 2 is controlled by a single dominant gene, whereas only partial polygenic resistance to race 1,2 has been described. We carried out a large-scale cDNA-AFLP analysis to identify host genes potentially related to resistance and susceptibility as well as fungal genes associated with the infection process. At the same time, a systematic reisolation procedure on infected stems allowed us to monitor fungal colonization in compatible and incompatible host-pathogen combinations. Results Melon plants (cv. Charentais Fom-2), which are susceptible to race 1,2 ...

Several recent studies have considered the relative effects of local vs. landscape factors on diversity of several animal taxa in grasslands. However, very few have considered vascular plant or Orthoptera species, both of which are important biotic components of grassland ecosystems. The ...