Varietà di orzo da malto per la produzione della birra.

Malattie fungine più diffuse sui frumenti biologici

Nell’annata agraria 2015-2016, nell'ambito della Rete nazionale prove biologiche frumento duro e della Rete nazionale prove biologiche frumento tenero, è stato valutato il comportamento di 22 e 18 varietà dell’una e dell’altra specie di frumento. Le prove sono state ospitate in 12 e 9 località dislocate su tutto il territorio nazionale. Le indagini fitopatologiche hanno evidenziato la comparsa di diversi patogeni. Nei campi sperimentali delle Reti nazionali di monitoraggio è stata confermata la presenza del complesso della septoriosi; un’attenzione particolare va sicuramente rivolta anche alla ruggine gialla.

Nitrogen efficiency in wheat as affected by crop rotation, tillage and N fertilization.

Long-term effects of contrasting tillage on soil organic carbon, nitrous oxide and ammonia emissions in a Mediterranean Vertisol under different crop sequences

This 2-year study aimed to verify whether the continuous application of no tillage (NT) for over 20 years, in comparison with conventional tillage (CT), affects nitrous oxide (NO) and ammonia (NH) emissions from a Vertisol and, if so, whether such an effect varies with crop sequence (continuous wheat, WW and wheat after faba bean, FW). To shed light on the mechanisms involved in determining N-gas emissions, soil bulk density, water filled pore space (WFPS), some carbon (C) and nitrogen (N) pools, denitrifying enzyme activity (DEA), and nitrous oxide reductase gene abundance (nosZ gene) were also assessed at 0–15 and 15–30 cm soil depth. Tillage system had no significant effect on total NH e…

Faba bean grain yield, N2 fixation, and weed infestation in a long-term tillage experiment under rainfed Mediterranean conditions

Background and Aims Long-term experiments could provide valuable information to determine the effects of an agronomic practice on agro-ecosystem productivity and stability. This study evaluated the long-term (18-year) impact of different tillage systems on faba bean (Vicia faba L.) productivity, including weed and broomrape incidence, and N2 fixation. Methods The experiment was carried out on a Vertisol under rainfed Mediterranean conditions. It was set up as a strip plot design. The tillage systems were: conventional tillage (CT) with moldboard plow, reduced tillage (RT) with chisel plow, and no tillage (NT). Nitrogen fixation was estimated over 2 years in the final phase of the experiment…

Valutazione di accessioni di trifoglio squarroso ed incarnato allevate con metodo biologico in coltura pura ed in consociazione con loiessa in ambiente mediterraneo.

Le varietà migliori per l’orzo da birra

Il 2016, come già il 2015, è stato un anno assai variegato per le produzioni, ma certamente più favorevole per la coltura dell’orzo primaverile al Centro-Nord rispetto al biennio 2013-2014

Varietà di grano duro a confronto in biologico.

Speciale orzo: produzioni ottime al Nord e buone al Centro-Sud

Il clima ha consentito una delle migliori stagioni a livello di rese compensando i prezzi bassi. Seconda stagione consecutiva positiva per gli agricoltori che hanno puntato sull’orzo. La produzione media complessiva al nord (33 varieta’ testate in 8 localita’ diverse) ha raggiunto le 7,6 t/ha; nel centro Italia, le 32 varieta’ testate nelle 6 località hanno registrato una media di 6,7 t/ha; infine, il sud ha registrato una rea media decisamente buona (5 t/ha) e superiore allo scorso anno. Inoltre, quest’anno l’andamento climatico ha reso conveniente fare orzo da birra anche al centro-nord.

Annata straordinaria per l’orzo al Nord Italia

La Rete delle prove nazionali di orzo da zootecnia per l’annata 2015-2016 evidenzia ottimi risultati produttivi soprattutto al Nord Italia. In questo articolo riportiamo la valutazione di 39 varietà ripartite in tre diversi gruppi varietali a seconda dell’areale interessato dalla sperimentazione (Nord, Centro, Sud e Isole)

Speciale orzo: un'annata al limite della perfezione.

L'andamento climatico favorevole ha consentito rese medie che non si registravano dal 2000. Il Nord torna alla ribalta dopo lo stop del 2011. Risultati eccellenti anche in termini di pesi ettolitrici.

Micotossine: nessun problema nel grano duro biologico.

Caratterizzazione fitopastorale e produttività di pascoli naturali ricadenti nel territorio del Parco dei Nebrodi.

Azotofissazione nel cece in ambiente mediterraneo.

Influenza di alcune tecniche agronomiche sulla produzione di seme di sulla (Hedysarum coronarium L.) allevata con metodo biologico in ambiente mediterraneo.

Long-term effects of contrasting tillage systems on soil C and N pools and on main microbial groups differ by crop sequence

Abstract Determining the best conservation agriculture practices for increasing soil organic carbon (C) and hence soil quality is of paramount importance in the semi-arid Mediterranean environment, where soils are experiencing a continuous decline in organic matter. Therefore, the aim of this long-term study was to assess the combined effects of tillage system and crop sequence on soil organic C and biochemical properties of soil generally used as indicators of soil quality. After 23 years of continuous application of contrasting tillage systems (conventional tillage [CT], vs. no tillage [NT]) and crop sequences (wheat monoculture vs. wheat-faba bean rotation), soil samples were collected f…

Grano duro biologico, le migliori varietà nelle prove 2015-2016

I risultati ottenuti nell’annata agraria 2015-16 relativi alle 22 varietà in prova nei 12 dispositivi sperimentali situati nei tre macroareali di coltivazione (Sud e isole, Centro tirrenico e Centro adriatico e Nord), hanno permesso di evidenziare una buona stabilità produttiva della varietà Iride, seguita da Claudio, Normanno e Saragolla, mentre tra le varietà testate da un minor numero di anni sono apparse molto interessanti Odisseo e Monastir.

Forage quality and yield of berseem clover and annual ryegrass grown in pure and mixed stands in relation to different N application rates

Effects of harvesting methods on seed yield and quality of Scorpiurs muricatus L..

Scorpiurus muricatus L. is an annual legume, widely distributed in Mediterranean pastures, that is appreciated by farmers for its productivity, forage quality, and palatability. It is characterised by long flowering and ripening periods and by pod shedding. These characteristics cause high seed losses, which could reduce its seed harvest efficiency in terms of seed yield and quality. In this study, we investigated the effects on seed yield and quality of different harvesting methods (windrowing at different times with subsequent combining was compared with direct combining). Our results show that direct combining when the pods were fully ripened reduced pod losses compared with swathing met…

Grano duro biologico: le varietà più adatte

Negli ultimi 6 anni i risultati produttivi della rete varietale bio premiano, per stabilità di resa, nell’areale Sud e Isole le varietà Claudio e Normanno; nel Centro Tirreno Iride; nel Centro adriatico e Nord Normanno e Anco Marzio.

Effetti della modalità di utilizzazione sulla produttività e sull’azotofissazione simbiotica del Trifolium squarrosum allevato in purezza o in consociazione con Avena sativa.

Effects of supplemental irrigation on berseem seed crop in a semi-arid Mediterranean environment

Varietà di orzo zootecnico: risultati produttivi e qualitativi.

Scelta delle varietà più adatte per il frumento duro biologico.

Forage and seed yield of sulla (Hedysarum coronarium L.) varieties and landraces in a semi-arid Mediterranean environment.

Conservation tillage in a semiarid Mediterranean environment: results of 20 years of research

Conservation tillage techniques are becoming increasingly popular worldwide as they have the potential to generate environmental, agronomic, and economic benefits. In Mediterranean areas, studies performed on the effects of conservation tillage [in comparison with the conventional tillage technique (CT)] on grain yield of cereal crops have reported contradictory results as well as considerable year-to-year variation, demonstrating how the impact of different soil tillage techniques on crop productivity is strongly site-specific. The present paper summarises the main results from a set of experiments carried out in Sicily during the last 20 years in which we compared no tillage (NT) to CT in…

Can arbuscular mycorrhizal fungi enhance plant nitrogen capture from organic matter added to soil?

Metabolomics Suggests That Soil Inoculation with Arbuscular Mycorrhizal Fungi Decreased Free Amino Acid Content in Roots of Durum Wheat Grown under N-Limited, P-Rich Field Conditions

Arbuscular mycorrhizal fungi (AMF) have a major impact on plant nutrition, defence against pathogens, a plant's reaction to stressful environments, soil fertility, and a plant's relationship with other microorganisms. Such effects imply a broad reprogramming of the plant's metabolic activity. However, little information is available regarding the role of AMF and their relation to other soil plant growth-promoting microorganisms in the plant metabolome, especially under realistic field conditions. In the present experiment, we evaluated the effects of inoculation with AMF, either alone or in combination with plant growth-promoting rhizobacteria (PGPR), on the metabolome and changes in metabo…

Unsupervised clustering method for pattern recognition in IIF images

Autoimmune diseases are a family of more than 80 chronic, and often disabling, illnesses that develop when underlying defects in the immune system lead the body to attack its own organs, tissues, and cells. Diagnosis of autoimmune pathologies is based on research and identification of antinuclear antibodies (ANA) through indirect immunofluorescence (IIF) method and is performed by analyzing patterns and fluorescence intensity. We propose here a method to automatically classify the centromere pattern based on the grouping of centromeres on the cells through a clustering K-means algorithm. The described method was tested on a public database (MIVIA). The results of the test showed an Accuracy…

Effects of stubble height and cutting frequency on regrowth of berseem clover in a Mediterranean semiarid environment

Defoliation management of forage crops affects endogenous reserves (in the root and in the stubble), the residual leaf area, and, consequently, the regrowth and biomass yield. The aim of this study was to evaluate the effect of cutting frequency (28-d vs. 35-d intervals) and stubble height (3 vs. 6 cm) on forage yield, regrowth, and persistence of berseem clover (Trifolium alexandrinum L.). Neither cutting interval nor cutting height affected plant survival during the crop cycle. Frequent clipping reduced crop yield. Residual biomass and leaf area were less when plants were cut at a height of 3 cm compared with 6 cm, but stubble height did not affect the total amount of dry matter (DM) remo…

Morphological and Physiological Root Traits and Their Relationship with Nitrogen Uptake in Wheat Varieties Released from 1915 to 2013

Identifying genotypes with a greater ability to absorb nitrogen (N) may be important to reducing N loss in the environment and improving the sustainability of agricultural systems. This study extends the knowledge of variability among wheat genotypes in terms of morphological or physiological root traits, N uptake under conditions of low soil N availability, and in the amount and rapidity of the use of N supplied with fertilizer. Nine genotypes of durum wheat were chosen for their different morpho-phenological characteristics and year of their release. The isotopic tracer 15N was used to measure the fertilizer N uptake efficiency. The results show that durum wheat breeding did not have univ…

Genetic diversity and potential agronomic value of Medicago polymorpha L. populations collected in Sicily.

Effects of arbuscular mycorrhizal symbiosis on growth and N2 fixation of Trifolium alexandrinum under late drought stress conditions.

Several experiments, mostly carried out under controlled conditions, have shown that arbuscular mycorrhizal (AM) symbiosis enhances nutrient uptake and improves drought tolerance of host plants. The present research, carried out in a typical Mediterranean environment, evaluated the effect of AM symbiosis on berseem clover (Trifolium alexandrinum L.) grown in the field under both late drought stress and well-watered conditions. The crop was subjected to repeated defoliation. N2 fixation was estimated using the 15N dilution method and using ryegrass (Lolium multiflorum var. Westervoldicum) as the reference crop. In late drought conditions, AM symbiosis resulted in a significant increase in bi…

Individuazione del periodo critico per il controllo delle infestanti in cece e favino.

Effects of grain legume crops on yield and quality of subsequent wheat crop grown at several rates of applied nitrogen

Pheno-morphological, agronomic and genetic diversity among natural populations of sulla (Hedysarum coronarium L.) collected in Sicily, Italy

Sulla (Hedysarum coronarium L.) is a short-lived perennial forage legume that plays a key role in cereal-based systems in semi-arid Mediterranean regions, particularly in organic production and low-input oriented agriculture. In Sicily, the species is widespread both as a wild and cultivated plant. The present study assessed the phenotypic and genetic variation among natural populations of sulla collected from different environments throughout Sicily and analysed how the patterns of phenotypic diversity varied according to the environmental parameters of each collection site. Two commercial varieties and two Sicilian agro-ecotypes were also included in the study as controls. Principal compo…

Le performance varietali del frumento duro biologico

Attitudine alla consociazione di diverse leguminose foraggere mediterranee.

Effetti della consociazione temporanea con favino sulla produttività e qualità del frumento duro in sistemi biologici.

Effects of feeding green forage of sulla (Hedysarum coronarium L.) on lamb growth and carcass and meat quality.

The nutritional effects of sulla (Hedysarum coronarium L.) forage containing condensed tannins (CT) on growth of lambs, and carcass and meat quality were investigated. Thirty-two male Comisana lambs aged 100 ± 8 days weighing 19.0 ± 2.8 kg were fed fresh forage of sulla or CT-free annual ryegrass (Lolium multiflorum Lam. subsp. Wersterwoldicum) for 49 days until slaughter; in addition, each lamb was supplied with 200 g/days of concentrate. Eight lambs per diet had been previously treated with anthelmintic drugs to remove nematode parasites. Measurements of BW and feed intake, and counts of faecal nematode eggs were made. Carcass parameters were recorded after slaughter, and tissue component…

Variation in pheno-morphological and agronomic traits among burr medic (Medicago polymorpha L.) populations collected in Sicily, Italy

The present study assessed the diversity of pheno-morphological and agronomic traits among 31 natural populations of burr medic (Medicago polymorpha L.) from different environments throughout Sicily, and analysed the patterns of phenotypic diversity in relation to the environmental parameters of each collection site. Three commercial cultivars (Cavalier, Santiago, and Anglona) were also included in the study as check cultivars. Two field experiments were performed in 2005–06 in a hilly area of the Sicilian inland. Principal components analysis (PCA) was performed on the sites using geographic, climatic, and pedological data to assess the differences in types of collection sites. PCA was al…

Molecular and agronomic responses to plant-growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal (AM) fungi in durum wheat

Plant-growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal (AM) fungi contribute to plant nutrient uptake by increasing the availability of nutrients and the root adsorbing surface (Garg et al., 2006; Asghar et al. 2002). The first objective of this study was to determine the effects of these associations on plant total biomass and grain yield in durum wheat (cv. Anco Marzio). Secondly, we aimed to analyze the root transcriptomic and metabolomic changes in response to mychorrizal infections and the expression pattern of key genes involved in nutrient uptake and stress responses. Field analysis were carried out in inner Sicily, a typical Mediterranean area. Four types of biotic a…

Sulla (Hedysarum coronarium L.) as Potential Feedstock for Biofuel and Protein

Although sulla (Hedysarum coronarium L.) has many interesting features that could support the production of biofuels (e.g., a high yield and soluble sugar content, N-fixation capacity, low input requirements for its cultivation), no study has assessed the possibility of its use for that purpose. Our objective was to evaluate the potential value for energy production of sulla cut at various stages of growth. Furthermore, the potential of sulla as a dual purpose crop (energy and feed) was investigated. The crop was grown in rainfed conditions in a typical Mediterranean environment (over two complete 2-year crop cycles) and was cut at four different phenological stages. The biomass was divided…

Rese e qualità di varietà di grano duro in biologico.

Development of a method for the direct fermentation of semolina by selected sourdough lactic acid bacteria

Three obligately heterofermentative lactic acid bacteria (LAB) strains (Lactobacillus sanfranciscensis PON100336, Leuconostoc citreum PON10079 and Weissella cibaria PON10030) were used in this study as a multi-species starter culture for sourdough production. The starter inoculum was prepared and propagated in sterile semolina extract (SSE) broth. Acidification kinetics, microbiological counts detected on specific media for sourdough LAB, polymorphic profile comparison and species-specific PCRs evidenced a stability of the liquid inoculum over time determining its suitability for direct addition to semolina. In order to validate this innovative method for the production of durum wheat (Trit…

Condensed tannins content in sulla (Hedysarum coronarium L.) as affected by environment, genotype and growth stage

Le varietà per l’orzo da malto

Per il Centro-sud e Isole la produzione ha superato di 0,3 t/ha quella dell’annata precedente attestandosi a 4,8 t/ha, mentre per il Centro-nord la media è stata di sole 3,1 t/ha. La sofferenza della coltura si è manifestata chiaramente anche in termini di ritardo della spigatura, avvenuta nell’ultima decade di maggio

Rese e qualità del grano duro in coltivazione biologica

Valutazione di genotipi di frumento duro in regime biologico in ambiente semi-arido mediterraneo.

Valutazione dell’Abilità Competitiva nei Confronti delle Malerbe di Genotipi Antichi e Moderni di Frumento Duro.

Computer-Assisted Classification Patterns in Autoimmune Diagnostics: The AIDA Project.

International audience; Antinuclear antibodies (ANAs) are significant biomarkers in the diagnosis of autoimmune diseases in humans, done by mean of Indirect ImmunoFluorescence (IIF) method, and performed by analyzing patterns and fluorescence intensity. This paper introduces the AIDA Project (autoimmunity: diagnosis assisted by computer) developed in the framework of an Italy-Tunisia cross-border cooperation and its preliminary results. A database of interpreted IIF images is being collected through the exchange of images and double reporting and a Gold Standard database, containing around 1000 double reported images, has been settled. The Gold Standard database is used for optimization of …

Performance of berseem clover varieties grown in organic farming in a semi-arid Mediterranean environment.

Yield And Competitive Ability Against Weeds Of Mixtures Between Old And Modern Wheat Varieties

Durum wheat is the keystone of the agro-ecosystems in the arable land of the Mediterranean environments and an important part of its area falls within organic farms. For this crop competition exerted by weeds for the use of resources (natural and auxiliary) can determine drastic yield and quality reductions (Ruisi et al., 2015). In organic farming such critical issue is often addressed through a remodelling of several techniques such as soil tillage management, sowing time, plant density and genotype choice. With regard to the latter, there is a growing interest by organic farmers towards the old varieties as they, compared to the modern varieties, have a definitely greater competitive weed…

Addition of high C:N crop residues to a P-limited substrate constrains the benefits of arbuscular mycorrhizal symbiosis for wheat P and N nutrition

Many aspects concerning the role of arbuscular mycorrhizal (AM) fungi in plant nutrient uptake from organic sources remain unclear. Here, we investigated the contribution of AM symbiosis to N and P uptake by durum wheat after the addition of a high C:N biomass to a P-limited soil. Plants were grown in pots in the presence or absence of a multispecies AM inoculum, with (Org) or without (Ctr) the addition of 15N-labelled organic matter (OM). A further treatment, in which 15N was applied in mineral form (Ctr+N) in the same amount as that supplied in the Org treatment, was also included. Inoculation with AM had positive effects on plant growth in both control treatments (Ctr and Ctr+N), mainly …

In vivo digestibility and nutritive value of Atriplex halimus alone and mixed with wheat straw

In vivo digestibility trials were carried out using six young rams fed with Atriplex halimus biomass harvested in summer (A) and in early autumn (B), and with a mixture of mid-autumn Atriplex halimus and wheat straw (5[ratio ]1 ratio on fresh matter basis) (C). Atriplex halimus had a high protein content (139·0, 135·9 and 193·4 g/kg DM in A, B and C respectively), but was rich in sodium chloride, especially in summer (145·9 g/kg DM), limiting its use as feed. The summer forage had a higher organic matter (OM) digestibility coefficient than the autumn forage (0·663 v. 0·530) but lower digestible OM intake (16·8 v. 29·4 g/day per kg BW0·75). In autumn forage, the combination with straw did no…

Characterization and preliminary evaluation of wild genetic resources of Hedysarum coronarium L. collected in Sicily.

Orzo da zootecnia: ripresa al Centro, cali al Sud

La rete delle prove nazionali di orzo da zootecnia per l’annata 2014-2015 mostra risultati molto diversi a seconda della località. La media produttiva al Nord risulta di 6,5 t/ha come lo scorso anno, al Centro in deciso aumento con 6,7 t/ha, mentre al Sud la produttività evidenzia una perdita di 1 t/ha.

Transcriptome changes induced by Arbuscular mycorrhizal symbiosis in leaves of durum wheat (Triticum durum Desf.) promote higher salt tolerance

AbstractThe salinity of soil is a relevant environmental problem around the world, with climate change raising its relevance, particularly in arid and semiarid areas. Arbuscular Mycorrhizal Fungi (AMF) positively affect plant growth and health by mitigating biotic and abiotic stresses, including salt stress. The mechanisms through which these benefits manifest are, however, still unclear. This work aimed to identify key genes involved in the response to salt stress induced by AMF using RNA-Seq analysis on durum wheat (Triticum turgidum L. subsp. durum Desf. Husn.). Five hundred sixty-three differentially expressed genes (DEGs), many of which involved in pathways related to plant stress resp…

Guida alla scelta delle varietà di orzo per la zootecnia

Piogge interminabili rese in forte calo

Il clima avverso è stato l'elemento chiave dell'annata, con un decremento delle produzioni fino al 30%. E il colpo di grazia potrebbe arrivare dalle micotossine.

Rese e qualità del grano duro per la coltivazione biologica

Berseem clover (Trifolium alexandrinum L.) seed production in Mediterranean environments.

Forage yield and N2 fixation of Trifolium alexandrinum in pure stand and in mixture with Lolium multiflorum.

The efficiency of grass-legume intercrop systems is affected by various agronomic factors such as crop density, plant spacing and arrangement that may alter the competitive relationships between component crops. This study was aimed to evaluate yield, N concentration, and symbiotic N2 fixation of berseem clover (Trifolium alexandrinum L.) grown in pure stand or in mixture with annual ryegrass (Lolium multiflorum Lam) either in alternating rows or in the same row. The experiment was conducted in two consecutive growing seasons in a semi-arid Mediterranean environment (Sicily, Italy). Dry matter (DM) yields were similar in the mixed stands and in the berseem pure stand; the annual ryegrass pu…

Le migliori varietà in prova di frumento duro biologico.

Le varietà di grano duro più vocate al biologico

Nella stagione 2015-2016 sono stati realizzati 12 campi, localizzati in 9 regioni e aggregati in tre macroareali: Sud-Isole (5 campi), versante Tirrenico dell’Italia Centrale (3 campi), versante Adriatico dell’Italia Centrale e Nord (4 campi). In tutti i campi sono state messe a confronto 22 varietà, di cui 1 (Orizzonte) al primo anno di prova, utilizzando uno schema sperimentale a blocchi randomizzati con 3 o 4 ripetizioni. Tutte le cultivar sono state fornite non conciate dalle ditte sementiere (la scheda agronomica delle prove e i principali rilievi eseguiti sono onsultabili all’indirizzo internet riportato in fondo all’articolo).

Polyester microplastic fibers affect soil physical properties and erosion as a function of soil type

Microplastics are recognized as a factor of global change contaminating many environmental compartments. Agricultural soils are very likely to receive microplastic contamination and are of particular concern due to their role in food production. Microplastic fibers have already been shown to be able to affect soil properties, but their effect on different soil types is poorly understood. Moreover, limited information is available on how the presence of this pollutant can affect soil water erosion processes, which are extremely important issues in many environments. In the light of this, we performed two experiments (carried out on a microscale) to investigate how the presence of polyester m…

Mediterranean forage legumes grown alone or in mixture with annual ryegrass: biomass production, N2 fixation, and indices of intercrop efficiency

Aims: To evaluate the productivity and N2 fixation of a range of Mediterranean forage legume species as well as their ability to be grown in mixture with a forage grass, and to verify whether N transfer occurs from the legume to the non-legume component of the mixtures and, if so, to what extent this process is affected by legume species. Methods: Seven legume species (Hedysarum coronarium L., Medicago scutellata L., Trifolium resupinatum L., Trifolium squarrosum L., Trigonella foenum-graecum L., Vicia sativa L., Vicia villosa Roth) were grown alone or in mixture with annual ryegrass (Lolium multiflorum L.). Biomass and N yields and biological N2 fixation (15N dilution technique) were measu…

Annata critica per il tenore proteico del frumento duro biologico

Speciale Orzo. Produzioni record al sud. Il nord soffre la pioggia

Microbial biomass carbon dynamics in a long-term tillage and crop rotation experiment under semiarid Mediterranean conditions

Microbial biomass carbon (MBC) of soil is an important ecological indicator of nutrient cycling and soil fertility. In addition, it responds to the changes of soil fertility more rapidly than soil organic matter. The aim of the present work was to evaluate the effect of a long-term implementation of a conservative soil management strategy (No Tillage [NT]) compared to the inversion tillage (conventional tillage [CT]) on the soil MBC in a range of crops - continuous durum wheat (WW), wheat after fababean (FW) and faba bean after wheat (WF). MBC of NT plots was higher than CT. In addition, the content of MBC varied with sampling time during the growing season; this variation did not show a co…

Tecniche conservative di gestione del suolo in ambiente mediterraneo: risultati di un ventennio di sperimentazioni.

Agroecosystem performances of livestock farms in a mountain area of Sicily

Gli orzi da birra per le semine 2011-12.

Effetti della competizione interspecifica sull’efficienza di utilizzazione dell’azoto in differenti genotipi di frumento duro al variare della disponibilità azotata.

Early sowing can boost grain production by reducing weed infestation in organic no‐till wheat

Conservative tillage techniques have several agro-ecological benefits for organic farming. The application of these techniques, however, can create quite a few challenges due to the increased weed competition. Here, we report the results of an organic field experiment in which the responses of wheat and weeds to no tillage (NT) were evaluated compared with conventional tillage (CT). We also tested the hypothesis that, under NT, moving up the sowing date, compared with using the ordinary sowing date for the study area, can result in increased competitiveness of the crop against weeds. Two wheat genotypes, a modern variety and an ancient landrace, were tested.Substantial reductions in grain y…

Mycorrhizae differentially influence the transfer of nitrogen among associated plants and their competitive relationships

Abstract The formation of a common mycorrhizal network among roots of different plant species growing close to each other can influence plant community dynamics, regulating plant relationships through the differential transfer of nutrients from one plant to another. However, knowledge of the mechanisms that regulate this process is poor. Here we quantify the contribution of arbuscular mycorrhizae to the transfer of N among heterospecific plants growing adjacent to each other and examine whether the differential transfer of N within the plant community via mycorrhizae can alter competitive relationships among plant species. Plants of four species (wheat, pea, flax, and chicory) were grown in…

Polyester microplastic fibers in soil increase nitrogen loss via leaching and decrease plant biomass production and N uptake

Abstract Microplastic contamination, like other global change factors, can induce effects on ecosystem functions and processes, affecting various soil biophysical properties. However, effects of such contaminants on nutrient cycles in agroecosystems are still poorly understood. We here performed two pot experiments to investigate the effect of polyester microplastic fibers (PMFs) on soil physical properties, nitrogen cycle, and plant performance in a maize-based agroecosystem. Moreover, we followed the N loss via leaching in soil contaminated or not with PMFs by simulating heavy rainfall events that mimic a future scenario of climate change. Our results show that soil contaminated with PMFs…

Le varietà per il duro biologico.

Rese e qualità del grano duro in coltivazione biologica.

Effects of harvest date on seed yield and quality of Scorpiurus muricatus L..

Risposta di genotipi siciliani di lenticchia (Lens culinaris Medik.) in diversi ambienti collinari

Orzo da malto, quali varietà scegliere

In generale, il 2015 è stato un anno decisamente diversificato per quanto riguarda le produzioni, ma certamente più favorevole per la coltura dell’orzo primaverile al Centro-Nord, che dopo due anni negativi si riallinea al 2012 con una media produttiva di 5,3 t/ha.

Nitrogen Transfer Is Enhanced By AMF Fungi In A Faba Bean/Wheat Intercropping

Intercropping is an agricultural practice that can offer several benefits allowing a better native resources use efficiency and, consequently, a restraint of the auxiliary inputs and often a greater production compared to the monocultures (Brooker et al. 2015). Several authors observed that, in a legume/non-legume mixture, one of the benefits could be the N transfer (up to 80 % of the non-legume N demand; Thilakarathna et al. 2016). The transfer may occur via different pathways: legume rhizodeposition, plant tissue decomposition and direct transfer through arbuscular mycorrhizal fungi (AMF) (Bedoussac et al. 2015). The latter, can simultaneously establish symbiotic relationship with differe…

Nitrogen efficiency component analysis in wheat under rainfed Mediterranean conditions: effects of crop rotation and nitrogen fertilization

The research was carried out in 1999-01 in a typical Sicilian semi-arid area to evaluate the effect of crop rotation and N fertilization on the nitrogen use efficiency (NUE) in wheat. Crop rotation were: wheat-faba bean, wheat-chickpea, wheat-pea and continuous wheat; nitrogen fertilizer rates were: 0, 40, 80 and 120 kg N/ha. A split-plot design with three replications were used. Analysis of nitrogen efficiency components was performed according to the procedure of Higgins and Pan (1993) using grain yield, aboveground plant N, grain N and post-harvest inorganic soil N. Continuous wheat (WW) recorder the lowest grain yields while no differences were found in wheat grown after the three legum…

The critical period of weed control in faba bean and chickpea in Mediterranean areas

Weeds are often the major biological constraint to growing legume crops successfully, and an understanding of the critical period of weed control (CPWC) is important for developing environmentally sustainable weed management practices to prevent unacceptable yield loss. Therefore, we carried out two field experiments to identify the CPWC for two grain legume crops traditionally grown in Mediterranean areas: chickpea and faba bean. The experiments were conducted at two sites both located in the Sicilian inland (Italy). In chickpea, when weeds were left to compete with the crop for the whole cycle, the grain yield reduction was on average about 85% of the weed-free yield, whereas in faba bean…

Varietà di grano duro per la coltivazione in bio.

Frumento duro biologico, le varietà consigliate

Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.

Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N) fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season) on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rai…

Impacts of arbuscular mycorrhizal fungi on nutrient uptake, N2 fixation, N transfer, and growth in a wheat/faba bean intercropping system

Arbuscular mycorrhizal fungi (AMF) can play a key role in natural and agricultural ecosystems affecting plant nutrition, soil biological activity and modifying the availability of nutrients by plants. This research aimed at expanding the knowledge of the role played by AMF in the uptake of macro- and micronutrients and N transfer (using a 15 N stem-labelling method) in a faba bean/wheat intercropping system. It also investigates the role of AMF in biological N fixation (using the natural isotopic abundance method) in faba bean grown in pure stand and in mixture. Finally, it examines the role of AMF in driving competition and facilitation between faba bean and wheat. Durum wheat and faba bea…

Energy use efficiency of livestock farms in a mountain area of Sicily

The research aimed to evaluate the performance (in terms of energy) of livestock farms located in a Mediterranean mountain area and characterized by different stocking rates. Farm data were collected from in-person interviews of farmers of 58 farms representative of the livestock farms of the Madonie and Nebrodi mountains area (Sicily, Italy), including several parameters related to farm characteristics, animal, crop and pasture management. The farm parameters were used to calculate input and output energy values from which agroecosystem performance indicators were derived. Increasing stocking rate corresponded to a more than proportional increase in total inputs per unit area because of a …

Effects of arbuscular mycorrhizal symbiosis on the nitrogen uptake of three durum wheat genotypes from two different organic sources

Al centro-nord vince la pioggia, bene solo il Meridione

Grano duro biologico: i consigli varietali.

Nell’annata agraria 2018-19, per il 17° anno consecutivo, sono state effettuate prove collegiali di confronto tra varietà di frumento duro in coltura biologica, in collaborazione con diverse Istituzioni. Le prove sono state realizzate in 7 località, dislocate in 6 regioni del Centro-Sud (Sicilia, Sardegna, Puglia, Toscana e Marche), utilizzando uno schema sperimentale a blocchi randomizzati con 3 o 4 ripetizioni. In tutti i campi sono state messe a confronto le stesse 19 varietà, fornite non conciate dalle ditte sementiere.A livello produttivo le varietà Emilio Lepido, Iride e Antalis hanno fornito i migliori risultati, mentre le varietà Aureo e Furio Camillo sono risultate, rispettivamente…

Effects of intraspecific competition on growth and seed yield of contrasting sulla genotypes.

Sulla (Hedysarum coronarium L.) is a short-lived perennial legume native to the Mediterranean basin, where it is grown extensively as a 2-year forage crop. Seed is often obtained as a secondary product from second-year crops established to produce forage. Very little information is available on seed yield capacity in the first year of the crop cycle and on the influence of agronomical techniques on the reproductive process. The present study aimed to evaluate the effect of intraspecific competition on dry matter accumulation (both in epigeic organs and in taproots) and seed production in the first year of a crop cycle for two contrasting genotypes. Two field trials were carried out in a Med…

Weed seedbank size and composition in a long-term tillage and crop sequence experiment

Summary Knowledge of the effects of agricultural practices on weed seedbank dynamics is essential for predicting future problems in weed management. This article reports data relative to weed seedbank structure after 18 years of continuous application of conventional tillage (CT, based on mouldboard ploughing) or no tillage (NT) within three crop sequences (continuous wheat, WW; wheat–faba bean, WF; and wheat–berseem clover, WB). Tillage system did not affect the size of the total weed seedbank, but altered both its composition and the distribution of seeds within the soil profile. In particular, the adoption of CT favoured some species (mainly Polygonum aviculare), whereas the continuous u…

Risultati del confronto tra varietà di orzo zootecnico

In tutti gli areali la sperimentazione condotta su 28 varietà ha fornito medie produttive assolutamente straordinarie; al Nord sono state prodotte mediamente 7,8 t/ha di granella d'orzo, al Centro 7,6 t/ha e al Sud e Isole 5,9 t/ha.

Varietà di orzo zootecnico: bene al Sud, meno al Nord

Al Nord la media dell' areale è stata di 6,5 t/ha in ripresa rispetto al tracollo della scorsa annata, al Centro è risultata di sole 5,1 t/ha, dato al di sotto delle potenzialità produttive; al Sud la produttività media è stata di 5,7 t/ha, un ottimo risultato che riporta l' areale su livelli elevati

Le varietà di orzo disponibili per la produzione della birra

Le cultivar in prova comprendevano 14 varietà, di cui 3 di tipo primaverile, 10 di tipo invernale e 1 di tipo facoltativo. Al Centro-Sud e Isole, la graduatoria varietale delle produzioni medie ha visto in prima posizione la cultivar Concerto; mentre, al Centro-Nord, la cultivar Doria (da zootecnia) si è attestata in prima posizione seguita da Tipple e Concerto.

Early Sowing Allows To Reduce Weed Pressure In No-Till Organic Durum Wheat Production

In organic farming, the adoption of the conventional tillage (CT) technique is considered by many farmers to be necessary to control weeds. Such tillage system, in fact, permits to bury weed seeds deep in the soil by means of soil inversion with moldboard plowing and to eliminate the weed plants that gradually emerge by means of the secondary tillage operations. However, it is also true that intensive tillage progressively reduces the soil organic matter content and the stability of soil aggregates, thus increasing the risk of soil erosion (Six et al. 2000). This is in contrast with one of the basic principles of organic agriculture, which is the conservation of soil fertility. Alternativel…

Long-term effects of no tillage treatment on soil N availability, N uptake, and 15N-fertilizer recovery of durum wheat differ in relation to crop sequence

Abstract No tillage (NT) soil management has largely been promoted because of its potential to generate both economic and environmental benefits. However, it often leads to reductions in crop yield and quality, which in many cases have been attributed to the effects this technique has on the nitrogen (N) dynamics in the soil–plant system. This 2-year study, performed within a long-term experiment in which NT was continuously applied for over 15 years, aimed to verify whether and to what extent the use of NT affects soil N availability, recovery of 15 N-labeled fertilizer, and N use efficiency (NUE) and its components (N uptake efficiency, NUpE; N utilization efficiency, NUtE). Durum wheat w…

Productivity and canopy modification of Medicago arborea as affected by defoliation management and genotype in a Mediterranean environment

Medicago arborea is one of the most potentially valuable fodder shrubs in a Mediterranean environment because of its high preference by small ruminants and its nutritive value. Edible biomass production is affected by agronomic and environmental factors. A study, carried out in an inland area of Sicily in the growing seasons of 1994/95, 1995/96 and 1996/97, evaluated the forage production and canopy modification in a M. arborea plantation after (i) commencing defoliation 1 or 2 years after transplanting and (ii) defoliating only in autumn (A), only in early summer (S) or in both seasons (A and S). Six clones derived from five different Mediterranean populations were used. Plant age at the f…

Long-term tillage and crop sequence effects on wheat grain yield and quality.

Much research around the world has compared the performance of cereals grown under conventional and conservation tillage systems; however, relatively few long-term experiments have been conducted in Mediterranean areas, and little attention has been given to interactions among tillage techniques and other system components across space and time. In this study, we investigated the effects of the long-term (18-yr) use of three tillage techniques (conventional tillage, CT; reduced tillage, RT; and no-till, NT) on wheat (Triticum durum Desf.) grain yield and quality within three crop sequences: continuous wheat, faba bean (Vicia faba L.)–wheat, and berseem clover (Trifolium alexandrinum L.)–whe…

Valutazione dell'efficienza d'uso dell'azoto in genotipi di frumento duro in ambiente mediterraneo

Wheat yield and grain quality as affected by tillage, sowing time and nitrogen fertilization under rainfed Mediterranean conditions

The research was carried out in 9 sites (5 in 1999-00 and 4 in 2000-01) of inner area of Sicily different for soil type, slope, exposure and preceding crop. The following treatments were studied: (i) conventional tillage and sowing at conventional time (CT); (ii) no tillage and sowing at conventional time (NTc); and (iii) no tillage and early sowing (NTe). In 2000-01 the effect of three nitrogen fertilization treatment (single application at planting, P, and split dressing at two different rates, S and S+) were also evaluated. No tillage systems (NTc and NTe) significantly increased grain yield compared to CT treatment; no differences were observed between the two sowing dates. The producti…

Strategies of weed control in organic seed production of sulla (Hedysarum coronarium L.) in a Mediterranean environment.

Cut and post-cut herbage management affects berseem clover seed yield.

The seed yield of berseem clover (Trifolium alexandrinum L.) is usually obtained from regrowth after forage utilization. In stockless, cereal-growing, or specialized seed farms the forage is not needed and the mowed herbage is seldom marketable. Three different experiments were conducted in a Mediterranean environment to evaluate the effect of returning the cut biomass to the soil/crop on the regrowth, seed yield, and seed quality of berseem clover. Different forms of cut and post-cut management were examined, in which the time of cutting, the amount of biomass returned to the crop/soil, and the size of the returned material (unchopped or chopped) all varied. In addition, the effect of the …

Identification of microRNAS differentially regulated by water deficit in relation to mycorrhizal treatment in wheat.

Arbuscular mycorrhizal fungi (AMF) are soil microrganisms that establish symbiosis with plants positively influencing their resistance to abiotic stresses. The aim of this work was to identify wheat miRNAs differentially regulated by water deficit conditions in presence or absence of AMF treatment. Small RNA libraries were constructed for both leaf and root tissues considering four conditions: control (irrigated) or water deficit in presence/absence of mycorrhizal (AMF) treatment. A total of 12 miRNAs were significantly regulated by water deficit in leaves: five in absence and seven in presence of AMF treatment. In roots, three miRNAs were water deficit-modulated in absence of mycorrhizal t…

Realizzazione e gestione degli inerbimenti nelle colture arboree

Nitrogen Availability Drives Mycorrhizal Effects on Wheat Growth, Nitrogen Uptake and Recovery under Salt Stress

The arbuscular mycorrhizal (AM) symbiosis is generally considered effective in improving salt tolerance in plants; however, the advantages it offers can vary greatly depending on the context in which it occurs; furthermore, the mechanisms underlying these responses are still unclear. A study was conducted to investigate the role of nitrogen (N) availability on the effectiveness of AM symbiosis in durum wheat (Triticum durum Desf.) plants grown under salt stress. Plants were grown in pots in the absence or in presence of salt stress (soil electrical conductivity of 1.50 and 13.00 dS m−1, respectively), with or without AM fungi inoculation (Rhizophagus irregularis and Funneliformis mosseae), …

Molecular and agronomic responses to soil inoculation with plant-growth promoting rhizobacteria and arbuscular mycorrhizae in Triticum durum

Plant-growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal (AM) fungi contribute to plant nutrient uptake by increasing the availability of nutrients and the root adsorbing surface. However, the molecular mechanisms of plant responses to these associations are still under-investigated. Gene expression analysis could lead to the identification of biomarkers usable to early select genotypes for an increased nutrient uptake efficiency. The main objective of this study was to determine the effects of these associations on plant total biomass and grain yield in durum wheat (cv. Anco Marzio). Secondly, we aimed to analyze the expression pattern of key genes involved in nutrient uptake…

Technical Note: Comparison of Techniques for Evaluating the Relative Preference by Sheep Among Saltbush Clones

This research compared 4 field methods of evaluating the relative preference by sheep of 28 clones of saltbush (Atriplex halimus L.). The methods were as follows. 1) Leaf dots (LD): 8 leaves per shrub were marked on the lower surface with a small dot using a water-resistant, nontoxic ink. 2) Twig marks (TM): 2 current-year twigs per shrub were marked with 3 lines using the same ink approximately in the middle of the basal, median, and apical thirds. 3) Branch length (BL): 2 branches per shrub were marked with ink at the base of the current year's growth. The twigs were measured from the marked point to the top, before and after sheep browsing. 4) Ocular estimation (OE): the percentage of th…

The effect of arbuscular mycorrhizal fungi on total plant nitrogen uptake and nitrogen recovery from soil organic material

SUMMARYArbuscular mycorrhizal (AM) fungi increase nitrogen (N) uptake by their host plants, but their role in plant N capture from soil organic material is still unclear. In particular, it is not clear if AM fungi compete with the host plant for the N coming from the decomposing organic matter (OM), especially when the AM extraradical mycelium (ERM) and plant roots share the same soil volume. The goal of the present research was to study the effects of AM fungi on wheat N capture after the addition of 15N-labelled OM to soil. Durum wheat (Triticum durum) was grown under controlled conditions in a sand:soil mix and the following treatments were applied: (1) AM inoculation with Glomus mosseae…

Valutazione di varietà di trifoglio alessandrino allevate in coltura pura e in consociazione con loiessa in regime biologico.

Hardseededness and patterns of seed softening in burr medic (Medicago polymorpha L.).

Long-term no-tillage application increases soil organic carbon, nitrous oxide emissions and faba bean (Vicia faba L.) yields under rain-fed Mediterranean conditions.

The introduction of legumes into crop sequences and the reduction of tillage intensity are both proposed as agronomic practices to mitigate the soil degradation and negative impact of agriculture on the environment. However, the joint effects of these practices on nitrous oxide (NO) and ammonia (NH) emissions from soil remain unclear, particularly concerning semiarid Mediterranean areas. In the frame of a long-term field experiment (23 years), a 2-year study was performed on the faba bean (Vicia faba L.) to evaluate the effects of the long-term use of no tillage (NT) compared to conventional tillage (CT) on yield and NO and NH emissions from a Vertisol in a semiarid Mediterranean environmen…

Effetti della Modalità di Gestione del Suolo e dell’Avvicendamento Colturale sulla Dinamica delle Popolazioni di Infestanti nel Frumento Duro in Ambiente Mediterraneo.

Pheno-morphological and agronomic diversity among Scorpiurus muricatus (Fabaceae) natural populations collected in Sicily.

SUMMARYPrickly scorpion's tail (Scorpiurus muricatus L.) is a self-reseeding annual legume widely distributed in natural pastures of the Mediterranean area and appreciated by farmers for its productivity, forage quality and palatability. Twenty-eight natural populations were collected throughout Sicily in 2005; two field experiments were carried out in 2005/06 in a hilly area of the Sicilian inland to assess the genetic variation based on pheno-morphological and agronomic characters. The pheno-morphological traits observed were analysed using a principal component analysis (PCA). The first four components of PCA (eigenvalues >1) explained 0·84 of the total variation. Similarities obtaine…

Switching from conventional tillage to no-tillage: Soil N availability, N uptake,15N fertilizer recovery, and grain yield of durum wheat

Abstract This 2-year study, performed in a typical Mediterranean environment on three soil types (two Inceptisols and one Vertisol), aimed to improve understanding of the factors that play a major role in determining crop response when soil management shifts from conventional tillage (CT) to no-tillage (NT). The effects of NT on the soil nitrogen (N) availability, N uptake, 15N fertilizer recovery, and grain yield of durum wheat were evaluated in comparison to CT under five different N fertilization rates (0, 40, 80, 120, and 160 kg N ha−1). Compared to CT, NT negatively affected grain yield in one of the two years but only in the two Inceptisols. On average, a considerable grain yield adva…

Nitrogen Use Efficiency and Nitrogen Fertilizer Recovery of Durum Wheat Genotypes as Affected by Interspecific Competition

A better understanding of the genotype response to N fertilization under weed competition is necessary to identify varieties that exhibit high N use effi ciency even when weeds compete for available N. Such varieties may be more suitable for low input or organic systems. Th is study assessed the variations in nitrogen use effi ciency (NUE) (and its components) and the recovery of 15 N-labeled fertilizer in three durum wheat (Triticum durum Desf.) genotypes (one landrace and two varieties that diff er in terms of plant growth, grain yield potential, and adaptability to stressful environments) grown in the presence or absence of interspecifi c competition and varying soil N availability (0 or…

Effects of soil inoculation with arbuscular mycorrhizal fungi on plant growth and nutrient uptake of some Mediterranean species grown under rainfed field conditions

Valutazione energetica delle colture da biodiesel in ambiente mediterraneo.

Agro-ecological benefits of faba bean for rainfed Mediterranean cropping systems

This paper reviews the main results from a set of experiments carried out in a semiarid Mediterranean environment during the past 25 years on faba bean (<em>Vicia faba</em> L.), a crop traditionally grown in southern Italy and Sicily under rainfed conditions. These experiments focused on the residual effects of faba bean on subsequent crop(s) and assessment of the nitrogen (N) balance during the crop cycle, paying attention to both the environmental release of N (losses via volatilisation and denitrification) and estimates of N2 fixation as influenced by tillage system, intercropping, and presence/absence of mycorrhizal inoculum. Faba bean relied on N2 fixation more than other g…

Nitrogen Type and Availability Drive Mycorrhizal Effects on Wheat Performance, Nitrogen Uptake and Recovery, and Production Sustainability

Plant performance is strongly dependent on nitrogen (N), and thus increasing N nutrition is of great relevance for the productivity of agroecosystems. The effects of arbuscular mycorrhizal (AM) fungi on plant N acquisition are debated because contradictory results have been reported. Using 15N-labeled fertilizers as a tracer, we evaluated the effects of AM fungi on N uptake and recovery from mineral or organic sources in durum wheat. Under sufficient N availability, AM fungi had no effects on plant biomass but increased N concentrations in plant tissue, plant N uptake, and total N recovered from the fertilizer. In N-deficient soil, AM fungi led to decreased aboveground biomass, which sugges…

Tillage effects on yield and nitrogen fixation of legumes in Mediterranean conditions

Published in Agron. J. 104:1459–1466 (2012) Posted online [DATE] doi:10.2134/agronj2012.0070 Copyright © 2012 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. I agricultural practices that involve the use of agrochemicals such as fertilizers, pesticides, and herbicides have greatly increased the global food supply but often with detrimental effects on the environment, such as contamination of ground…

Forage production, N uptake, N2 fixation, and N recovery of berseem clover grown in pure stand and in mixture with annual ryegrass under different managements

In Mediterranean countries, forage grasses and legumes are commonly grown in mixture because of their ability to increase herbage yield and quality compared with monocrop systems. However, the benefits of intercropping over a monocrop system are not always realized because the efficiency of a grass–legume mixture is strongly affected by agronomic factors. The present study evaluated productivity, N2 fixation, N transfer, and N recovery of berseem clover (Trifolium alexandrinum) grown in pure stand and in mixture with annual ryegrass (Lolium multiflorum) under high or low defoliation frequencies and varying plant arrangements (sowing in the same row or in alternating rows). On average, the b…

Rese e qualità del grano duro in coltivazione biologica.

Nitrogen uptake and nitrogen fertilizer recovery in old and modern wheat genotypes grown in the presence or absence of interspecific competition

Choosing genotypes with a high capacity for taking up nitrogen (N) from the soil and the ability to efficiently compete with weeds for this nutrient is essential to increasing the sustainability of cropping systems that are less dependent on auxiliary inputs. This research aimed to verify whether differences exist in N uptake and N fertilizer recovery capacity among wheat genotypes and, if so, whether these differences are related to a different competitive ability against weeds of wheat genotypes. To this end, 12 genotypes, varying widely in morphological traits and year of release, were grown in the presence or absence of interspecific competition (using Avena sativa L. as a surrogate wee…

Conventional tillage versus no-tillage: Nitrogen use efficiency component analysis of contrasting durum wheat genotypes grown in a Mediterranean environment

Very little information is available for Mediterranean areas about the soil N dynamics and crop N use efficiency during the transition phase from conventional tillage (CT) to no-tillage (NT). Hence, a 2-yr experiment was conducted under semiarid Mediterranean conditions in three sites to study how soil N dynamics, crop N uptake, grain yield, and N use efficiency vary with N-fertilization rate and crop genotype in the switch year from CT to NT. Treatments consisted of two tillage systems (CT and NT), five N-fertilization rates (0, 40, 80, 120, and 160 kg N ha−1), and two durum wheat (Triticum durum Desf.) genotypes (one modern variety and one old landrace). Irrespective of the genotype, NT r…

Effect of defoliation management and plant arrangement on yield and N2 fixation of berseem-annual ryegrass mixture

The research was carried out in a Mediterranean semi-arid environment on berseem clover, annual ryegrass and their mixture to study the effect of defoliation management [date of first cut (FC) 85, 119, 140, 169 days after sowing] and different plant arrangements (sowing the two components in alternate rows or in the same row) on yields, N content, N2 fixation and N transfer. The experimental design was a split-plot with four replications. The 15 N isotope dilution technique was used (8 kg N ha –1 as ammonium sulphate at 10 atom% 15 N excess) to evaluate the N2 fixation. Total seasonal DM yield was, on average, significantly higher for FC119 and FC140 (approx. 12.3 t ha –1 ) than for FC85 and FC…

Productivity of an Atriplex halimus shrubbery and effects of grazing on lambs

The objectives of this study were to 1) evaluate the productivity and forage quality of Atriplex halimus, 2) investigate modifications to shrub structure induced by grazing, and 3) assess live weight changes in lambs grazing on A. halimus with and without a feed supplement (wheat straw &plusmn; barley grain). The results showed that A. halimus had low productivity (approximately 1000 kg DM ha&ndash;1) but high tolerance to grazing by lambs, although minor modifications in plant structure due to grazing were observed. Lambs grazing A. halimus as a sole diet lost weight (about 60 g lamb&minus;1 d&ndash;1; P < 0.01), probably as a consequence of the high salt content of the forage reducing bot…