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

2021

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…

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

2021

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…

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

2018

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…

Arbuscular mycorrhizal symbiosis mitigates the negative effects of salinity on durum wheat

2017

Arbuscular mycorrhizal (AM) symbiosis is generally considered to be effective in ameliorating the plant tolerance to salt stress. Unfortunately, the comprehension of the mechanisms implicated in salinity stress alleviation by AM symbiosis is far from being complete. Thus, an experiment was performed by growing durum wheat (Triticum durum Desf.) plants under salt-stress conditions to evaluate the influence of AM symbiosis on both the plant growth and the regulation of a number of genes related to salt stress and nutrient uptake. Durum wheat plants were grown outdoors in pots in absence or in presence of salt stress and with or without AM fungi inoculation. The inoculum consisted of a mixture…

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

2021

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 …

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

2022

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…

Influence of grain quality, semolinas and baker’s yeast on bread made from old landraces and modern genotypes of Sicilian durum wheat

2021

Abstract Several studies showed that products made with ancient wheat genotypes have beneficial health properties compared to those obtained with modern wheat varieties, even though the mechanisms responsible for the positive effects are not clear. Ancient durum wheat genotypes are being currently used for the production of pasta, bread and other typical bakery products but the consumption is strictly local. In this work 15 genotypes of Triticum turgidum subsp. durum, including 10 ancient and 5 modern, were characterized for their technological traits through the determination of different parameters: protein content, dry gluten, gluten index, yellow index, ash, P/L, W and G. In addition, t…

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

2021

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…

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

2022

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

2021

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

2022

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…

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

2018

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…

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

2019

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…

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

2018

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…

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

2019

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…

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

2022

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), …

Soil Nitrogen Form and Availability affect the role of Arbuscular Mycorrhizal Fungi on Nitrogen Uptake and Nitrogen Recovery in Durum Wheat

2018

The term Arbuscular Mycorrhizal (AM) is referred to the symbiosis between arbuscular mycorrhizal fungi (AMF) and plant roots. Such symbiosis is the most widespread among plants (two out of three of the all plant taxa) including the majority of crops. AMF belong to the monophyletic subphylum Glomeromycotina which include obligate biotrophs that entirely relay on the host plant for the carbon source. In exchange, AMF provide their host several benefits which have been recognise in mitigation of biotic and abiotic stress, even though the main benefit ascribe to AMF is improving P uptake. However, although the AM symbiosis is considered as a classic example of a mutualistic symbiosis, many fact…

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

2018

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

2020

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…

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

2023

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…

Grano duro 2019: Italia divisa in due per rese e qualità. Dettaglio regionale dei risultati 2019: Sicilia.

2019

Nell’annata agraria 2018-2019 la Rete nazionale di valutazione delle varietà di frumento duro, coordinata dal CREA, ha previsto l’allestimento in Sicilia di quattro campi sperimentali, realizzati nei seguenti ambienti: Libertinia (Catania), Catania, S. Stefano Quisquina (Agrigento) e Caltagirone (Catania). Irisultati di quest’annata agraria hanno mostrato risposte produttive interessanti di diverse nuove varietà che, al primo anno di valutazione nella Rete nazionale, si affacciano sul mercato sementiero del frumento duro. Tali risultati andranno verificati nelle successive stagioni colturali.

Microplastic incorporation into soil in agroecosystems

2017

Background: We live in a plastic age (Thompson et al., 2009), with microplastic (typically defined as plastic particles < 5 mm) becoming an increasingly appreciated aspect of environmental pollution. Research has been overwhelmingly focused on aquatic systems, especially the oceans, but there is a current shift to more strongly consider terrestrial ecosystems (Rillig, 2012; Horton et al., 2017). In particular agroecosystems are coming into focus as a major entry point for microplastics in continental systems (Nizzetto et al., 2016b), where contamination might occur via different sources as sludge amendment or plastic mulching (Steinmetz et al., 2016). Given the central role of agroecosystem…

"Role of Arbuscular Mycorrhizal Fungi in Nutrient Uptake and Growth of Durum Wheat"

Soil microbiome is involved at different levels in the food web, in bio-geochemical nutrient cycles and in several interactions with plants. Based on its key role in the agro-ecosystem processes, the soil microbiome has been identified as one of the principal factors in an agriculture addressed to the ecological intensification. Among the several relationships established between plants and soil microorganisms, arbuscular mycorrhizal (AM) symbiosis is the most widespread. Two out of three of all plant taxa (among others the main crops) are involved in the AM symbiosis which takes place between the plant root system and arbuscular mycorrhizal fungi (AMF), a monophyletic group of fungi belong…

Subsoil Arbuscular Mycorrhizal Fungi for Sustainability and Climate-Smart Agriculture: A Solution Right Under Our Feet?

2019

With growing populations and climate change, assuring food and nutrition security is an increasingly challenging task. Climate-smart and sustainable agriculture, that is, conceiving agriculture to be resistant and resilient to a changing climate while keeping it viable in the long term, is probably the best solution. The role of soil biota and particularly arbuscular mycorrhizal (AM) fungi in this new agriculture is believed to be of paramount importance. However, the large nutrient pools and the microbiota of subsoils are rarely considered in the equation. Here we explore the potential contributions of subsoil AM fungi to a reduced and more efficient fertilization, carbon sequestration, an…