Effects of N fertilization on yield for low-input production in Spanish what landraces ( Triticum tugidum L. and Triticum monococcum L.)

A core subset of Spanish durum wheat landraces was evaluated at two nitrogen levels (80 and 220 kg/ha) to identify landrace genotypes adapted to low N production. Yield differences were statistically significant between N levels and among genotypes at both levels. Fiftyone per cent of the landraces yielded significantly more at low than at high N (low-N varieties) while 26% had a positive (high-N varieties) and 23% an indifferent (indifferent-N varieties) response to N fertilizer. No significant agromorphological differences were found among low and high-N varieties at low N level that conferred some advantage to low-N varieties. In contrast, high-N varieties possessed longer grain-filling period under high N level. Phenological characters showed an important influence on yield and on the performance of the varieties within each subgroup. The traits affecting grain yield most positively, mainly the low-N varieties, were long filling period and earliness. Five entries were selected for prebreeding to low N adaptation

Selecting Lucerne (Medicago Sativa Complex) for Traits Conferring Adaptation to Grazing

A germplasm collection of the Medicago sativa complex was evaluated to select genotypes possessing traits possibly conferring adaptation to grazing. Deep-crowned plants, either creeping-rooted or rhizomatous, were found with different frequencies, in all “taxonomic” groups examined. Although belonging to subsp. sativa, “mielga” wild populations from Spain were closer to subsp. falcata for morpho-physiological traits. Deep-crowned plants could be categorised into four top-growth models, to which corresponded a fairly distinct underground morphology: three were rhizomatous and one creeping-rooted. Cultivars selected for creeping-rootedness did not outyield rhizomatous populations of subsp. x varia which, in turn, had better spreading ability. In a subsequent evaluation, clones from selected rhizomatous genotypes had higher yield and better spreading ability than those from selected creeping genotypes. Under the given conditions, expression of creeping-rootedness was always erratic. The results point to the opportunity to pay greater attention to rhizomatous types in breeding grazing-tolerant cultivars

Response of Contrasting Cocksfoot Varieties to Summer Moisture Availability in a Mediterranean Environment

The responsiveness to water availability in summer and the effect of summer drought were assessed in a Mediterranean environment on both temperate and Mediterranean cocksfoot (Dactylis glomerata L.) materials. Three consecutive evaluation phases were contemplated: i) under rainfed conditions from autumn to spring; ii) under contrasting moisture conditions in the following summer; and iii) under rainfed conditions in the subsequent autumn-spring season to assess the effect of the previous summer treatments. The ability to become summer dormant under conducive conditions, such as in Mediterranean germplasm, proved a plant pre-requisite for survival under drought. All the “summer-active”, temperate varieties did not survive drought stress. Mediterranean materials showed a facultative dormancy behaviour in that they responded to moisture availability in summer. There was evidence that selection for such responsiveness was effective, as shown by a variety selected from Mediterranean germplasm also considering this criterion. Forcing summer growth by preventing dormancy had little detrimental effect on subsequent autumn recovery of Mediterranean improved varieties but more evidence is required on this aspect

Criteria for the Registration of \u3cem\u3eMedicago polymorpha\u3c/em\u3e L. and \u3cem\u3eLolium rigidum\u3c/em\u3e Gaud. Varieties in a Voluntary Register in Italy

Extensive and semi-extensive livestock systems in Southern Europe rely largely on permanent pastures, the productivity of which could be improved by sowing adapted species. Native forage species are a valuable tool for Mediterranean livestock production, owing to their specific adaptation to the harsh environment (featuring prolonged and severe spring-summer drought) and their generally good tolerance to grazing. Annual, self-reseeding species are able to cope with the prevailing drought stress by terminating the vegetative phase and setting seed before the onset of the stressful period, and enhance the durability of the sward by their self-reseeding capacity and subsequent seedling regeneration. Subterranean clover (Trifolium subterraneum L.) and medics (annual Medicago spp.) among the legumes, and annual ryegrass (Lolium rigidum Gaud.) among the grasses, are the most exploited self-reseeding species for pasture establishment

Morphological variation and inter-relationships of quantitative traits in enset (Ensete ventricosum (welw.) Cheesman) germplasm from South and South-Western Ethiopia

Enset (Ensete ventricosum (Welw.) Cheesman) is Ethiopia's most important root crop. A total of 387 accessions collected from nine different regions of Ethiopia were evaluated for 15 quantitative traits at Areka Agricultural Research Centre to determine the extent and pattern of distribution of morphological variation. The variations among the accessions and regions were significant (p ≤ 0.01) for all the 15 traits studied. Mean for plant height, central shoot weight before grating, and fermented squeezed kocho yield per hectare per year showed regional variation along an altitude gradient and across cultural differences related to the origin of the collection. Furthermore, there were significant correlations among most of the characters. This included the correlation among agronomic characteristics of primary interest in enset breeding such as plant height, pseudostem height, and fermented squeezed kocho yield per hectare per year. Altitude of the collection sites also significantly impacted the various characteristics studied. These results reveal the existence of significant phenotypic variations among the 387 accessions as a whole. Regional differentiations were also evident among the accessions. The implication of the current results for plant breeding, germplasm collection, and in situ and ex situ genetic resource conservation are discussed

Bosentan and macitentan prevent the endothelial-to-mesenchymal transition (EndoMT) in systemic sclerosis: in vitro study.

Background: Systemic sclerosis (SSc) is characterized by early vascular abnormalities and subsequent fibroblast activation to myofibroblasts, leading to fibrosis. Recently, endothelial-to-mesenchymal transition (EndoMT), a complex biological process in which endothelial cells lose their specific markers and acquire a mesenchymal or myofibroblastic phenotype, has been reported in SSc. In the present study, we evaluated the ability of endothelin-1 (ET-1) dual receptor antagonists bosentan (BOS) and macitentan (MAC) to antagonize EndoMT in vitro. Methods: Ten women with limited SSc were enrolled. They underwent double skin biopsy (affected and nonaffected skin). Fibroblasts and microvascular endothelial cells (MVECs) were isolated from biopsies. We performed mono- or coculture of MVECs (isolated from nonaffected skin) with fibroblasts (isolated from affected skin and stimulated with ET-1 and transforming growth factor beta [TGF-\u3b2]). In cocultures, the MVEC layer was left undisturbed or was preincubated with BOS or MAC. After 48 h of coculture, MVECs were analyzed for their tube formation ability and for messenger RNA and protein expression of different vascular (CD31, vascular endothelial growth factor-A [VEGF-A], VEGF-A165b) and profibrotic (alpha-smooth muscle actin [\u3b1-SMA], collagen type I [Col I], TGF-\u3b2) molecules. Results: After 48 h, MVECs showed a reduced tube formation ability when cocultured with SSc fibroblasts. CD31 and VEGF-A resulted in downregulation, while VEGF-A165b, the antiangiogenic isoform, resulted in upregulation. At the same time, mesenchymal markers \u3b1-SMA, Col I, and TGF-\u3b2 resulted in overexpression in MVECs. Tube formation ability was restored when MVECs were preincubated with BOS or MAC, also reducing the expression of mesenchymal markers and restoring CD31 expression and the imbalance between VEGF-A and VEGF-A165b. Conclusions: With this innovative EndoMT in vitro model realized by coculturing nonaffected MVECs with affected SSc fibroblasts, we show that the presence of a myofibroblast phenotype in the fibroblast layer, coupled with an ET-1-TGF-\u3b2 synergic effect, is responsible for EndoMT. BOS and MAC seem able to antagonize this phenomenon in vitro, confirming previous evidence of endothelium-derived fibrosis in SSc and possible pharmacological interferenc

Alfalfa genomic selection for different stress-prone growing regions

Alfalfa (Medicago sativa L.) selection for stress-prone regions has high priority for sustainable crop–livestock systems. This study assessed the genomic selection (GS) ability to predict alfalfa breeding values for drought-prone agricultural sites of Algeria, Morocco, and Argentina; managed-stress (MS) environments of Italy featuring moderate or intense drought; and one Tunisian site irrigated with moderately saline water. Additional aims were to investigate genotype × environment interaction (GEI) patterns and the effect on GS predictions of three single-nucleotide polymorphism (SNP) calling procedures, 12 statistical models that exclude or incorporate GEI, and allele dosage information. Our study included 127 genotypes from a Mediterranean reference population originated from three geographically contrasting populations, genotyped via genotyping-by-sequencing and phenotyped based on multi-year biomass dry matter yield of their dense-planted half-sib progenies. The GEI was very large, as shown by 27-fold greater additive genetic variance × environment interaction relative to the additive genetic variance and low genetic correlation for progeny yield responses across environments. The predictive ability of GS (using at least 37,969 SNP markers) exceeded 0.20 for moderate MS (representing Italian stress-prone sites) and the sites of Algeria and Argentina while being quite low for the Tunisian site and intense MS. Predictions of GS were complicated by rapid linkage disequilibrium decay. The weighted GBLUP model, GEI incorporation into GS models, and SNP calling based on a mock reference genome exhibited a predictive ability advantage for some environments. Our results support the specific breeding for each target region and suggest a positive role for GS in most regions when considering the challenges associated with phenotypic selection.EEA Santiago del EsteroFil: Annicchiarico, Paolo. Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria. Centro di Ricerca Zootecnia e Acquacoltura; ItaliaFil: Nazzicari, Nelson. Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria. Centro di Ricerca Zootecnia e Acquacoltura; ItaliaFil: Bouizgaren, Abdelaziz. Institut National de la Recherche Agronomique du Maroc. Centres Régionaux de Marrakech et de Rabat; MarruecosFil: Hayek, Taoufik. Institut des Régions Arides de Médenine; TunezFil: Laouar, Meriem. Ecole Nationale Supérieure Agronomique. Dép. de Productions Végétales. Laboratoire d’Amélioration Intégrative des Productions Végétales; ArgeliaFil: Cornacchione, Monica. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santiago del Estero; ArgentinaFil: Basigalup, Daniel Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi. Grupo de Mejoramiento Genético de Alfalfa; ArgentinaFil: Monterrubio Martin, Cristina. Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria. Centro di Ricerca Zootecnia e Acquacoltura; ItaliaFil: Brummer, E. Charles. University of California at Davies. Depeparment of Plant Sciences. Plant Breeding Center,; Estados UnidosFil: Pecetti, Luciano. Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria. Centro di Ricerca Zootecnia e Acquacoltura; Itali

Open questions and research needs in the adoption of conservation agriculture in the mediterranean area

This article aims to provide a review of major challenges and research needs for the diffusion of conservation agriculture (CA) and the improvement of crop–soil–water conditions in Southern Europe and Northern Africa. A multidisciplinary study and a participatory approach are at the basis of an international project of research and innovation action, “Research-based participatory approaches for adopting conservation agriculture in the Mediterranean Area-CAMA”. It aims to understand the reasons and the research needs that limit a large CA diffusion in the Mediterranean countries. CAMA aims to provide significant advances to CA through multidisciplinary research at the field and farm scales (with main emphasis on smallholder), encompassing a socio-economic analysis of the reasons that obstacle the CA diffusion, legume crop improvement as a component of improved CA cropping systems, and a network of long-term experiments on CA and soil characteristic modification. Its results will be available to scientific and farming communities.This research received the financial funding by PRIMA (Grant Agreement n. 1912), a programme supported by the European Union, research project “Research-based participatory approaches for adopting Conservation Agriculture in the Mediterranean Area – CAMA”, coord. Dott. Michele Rinaldi. Special thanks to Fabrice Dentressangle, CAMA Project Officer and to “Italian PRIMA Secretariate” office

High-density molecular characterization and association mapping in Ethiopian durum wheat landraces reveals high diversity and potential for wheat breeding

Durum wheat (Triticum turgidum subsp. durum) is a key crop worldwide, yet its improvement and adaptation to emerging environmental threats is made difficult by the limited amount of allelic variation included in its elite pool. New allelic diversity may provide novel loci to international crop breeding through quantitative trait loci (QTL) mapping in unexplored material. Here we report the extensive molecular and phenotypic characterization of hundreds of Ethiopian durum wheat landraces and several Ethiopian improved lines. We test 81,587 markers scoring 30,155 single nucleotide polymorphisms and use them to survey the diversity, structure, and genome-specific variation in the panel. We show the uniqueness of Ethiopian germplasm using a siding collection of Mediterranean durum wheat accessions. We phenotype the Ethiopian panel for ten agronomic traits in two highly diversified Ethiopian environments for two consecutive years, and use this information to conduct a genome wide association study. We identify several loci underpinning agronomic traits of interest, both confirming loci already reported and describing new promising genomic regions. These loci may be efficiently targeted with molecular markers already available to conduct marker-assisted selection in Ethiopian and international wheat. We show that Ethiopian durum wheat represents an important and mostly unexplored source of durum wheat diversity. The panel analyzed in this study allows the accumulation of QTL mapping experiments, providing the initial step for a quantitative, methodical exploitation of untapped diversity in producing a better wheat