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Background: Durum wheat (Triticum turgidum L. ssp. durum Desf. Husn) is the main staple crop used to make pasta products worldwide. Under the current climate change scenarios, genetic variability within a crop plays a crucial role in the successful release of new varieties with high yields and wide crop adaptation. In this study we evaluated a durum wheat collection consisting of 197 genotypes that mainly comprised a historical set of Argentinian germplasm but also included worldwide accessions. Results: We assessed the genetic diversity, population structure and linkage disequilibrium (LD) patterns in this collection using a 35 K SNP array. The level of polymorphism was considered, taking account of the frequent and rare allelic variants. A total of 1547 polymorphic SNPs was located within annotated genes. Genetic diversity in the germplasm collection increased slightly from 1915 to 2010. However, a reduction in genetic diversity using SNPs with rare allelic variants was observed after 1979. However, larger numbers of rare private alleles were observed in the 2000–2009 period, indicating that a high reservoir of rare alleles is still present among the recent germplasm in a very low frequency. The percentage of pairwise loci in LD in the durum genome was low (13.4%) in our collection. Overall LD and the high (r2 > 0.7) or complete (r2 = 1) LD presented different patterns in the chromosomes. The LD increased over three main breeding periods (1915–1979, 1980–1999 and 2000–2020). Conclusions: Our results suggest that breeding and selection have impacted differently on the A and B genomes, particularly on chromosome 6A and 2A. The collection was structured in five sub-populations and modern Argentinian accessions (cluster Q4) which were clearly differentiated. Our study contributes to the understanding of the complexity of Argentinian durum wheat germplasm and to derive future breeding strategies enhancing the use of genetic diversity in a more efficient and targeted way. Fil: Roncallo, Pablo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentina Fil: Larsen, Adelina Olga. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Barrow; Argentina Fil: Achilli, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentina Fil: Saint Pierre, Carolina. Centro Internacional de Mejoramiento de Maíz y Trigo; México Fil: Gallo, Cristian Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentina Fil: Dreisigacker, Susanne. Centro Internacional de Mejoramiento de Maíz y Trigo; México Fil: Echenique, Carmen Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentina

The granulation step determines the production yield and the final characteristics of the agglomerated couscous grains of durum wheat. The objective of the present work was to explore the capability of the fluidised bed technology to produce agglomerates of durum wheat semolina. The impacts of different processing conditions have been investigated on the structure and functional properties of the agglomerates. The size, shape, water content, compactness, and mechanical strength of the granules were measured. The fluidized bed agglomeration process has been found to produce agglomerates of durum wheat with different attributes compared to those produced by granulation using the low shear mixers. The results were discussed in regard to the hydro-textural approach, in order to get a better understanding of the mechanisms and relationships between process, structure, and properties. Two major agglomeration mechanisms contribute to the growth of the wet agglomerates: a fractal-structuring process followed by a phenomenon of densification. By studying the evolution of the compactness, diameter and water content, it was demonstrated that inter granular arrangements led to an expansion followed by a densification of the wet agglomerates. A relationship was proposed to describe the growth using a fluidized bed of the wet agglomerates of durum wheat semolina.

Leaf rust is responsible for significant wheat yield losses. Its occurrence and severity have increased in recent years, partly because of warmer climate. It is therefore critical to understand and anticipate the effects of climate change on leaf rust. Direct climate effects and indirect effects via host plants that provide a biophysical environment for disease development were both considered. The coupled STICS-MILA model simulates both crop and pathogen dynamics in a mechanistic way and their interaction is managed by two sub-models: one calculating the microclimate within the canopy and the other converting numbers of spores and lesions to affected surfaces. In this study, STICS-MILA was first calibrated and evaluated using leaf rust severity observed at various sites in France for multiple years. STICS-MILA was then run on three contrasting French sites under 2.6, 4.5 and 8.5 RCP future climate scenarios. Results focused firstly on changes in disease earliness and intensity, secondly on disease dynamics, particularly the synchronism between plant and disease developments, and finally on elementary epidemic processes. The calibration and evaluation of STICS-MILA revealed a high sensitivity to the initial amount of primary inoculum (a forcing variable in STICS-MILA) and thus the need to properly simulate the summering and overwintering pathogen survival. The simulations in the context of future climate showed a significant change in host-pathogen synchronism: in the far future, according to RCP 4.5 and 8.5 scenarios, disease onset is expected to occur not only with an advance of around one month but also at an earlier developmental stage of wheat crops. This positive effect results from rising temperatures, nevertheless partly counter-balanced during spring by lower wetness frequency. The crop growth accelerates during juvenile stages, providing a greater support for disease development. The resulting microclimate shortens latency periods and increases infection and sporulation efficiencies, thus causing more infectious cycles. An increase of final disease severity is thus forecasted with climate change.

Цель. Анализ распространённости вредителей и выявление устойчивого селекционного материала яровой твёрдой пшеницы в степной зоне оренбургского Предуралья. Материалы и методы. Энтомологические обследования проводили в питомнике конкурсного сортоиспытания 2014-2018 гг. по общепринятым методикам. Результаты. В условиях степи Оренбуржья большой вред посевам яровой твёрдой пшеницы наносят шведская муха, клоп вредная черепашка, хлебный жук кузька. Исследования выявили, что на распространённость вредителей и их вредоносность сильное влияние оказывают погодные условия периода вегетации растений пшеницы. Заселённость посевов шведской мухой в благоприятные для развития вредителя годы достигает 50-60%, а доля повреждённых растений составляет 19-27%. Численность клопа черепашки была на уровне 2,0-2,1 экземпляров на 1 квадратный метр, количество повреждённых растений – 0,67-0,71% . Распространённость жука кузьки в фазу молочной спелости доходит до 5-10 экземпляров на 1 кв. метр, количество повреждённых растений – 15-30% и степень повреждённости зерна в колосе – 10-35%. При оценке селекционного материала выявлены устойчивые к определённым вредителям формы яровой твёрдой пшеницы. Заключение. Эффективность селекционной работы на адаптивность к условиям степи Оренбургской области зависит от качества исходного материала используемого в гибридизации. Устойчивые к биотическим стресс-факторам внешней среды формы пшеницы являются ценным селекционным материалом. Высокую устойчивость к изученным в опытах вредителям показывает селекционный номер Д-6501. Хлебной полосатой блошкой и клопом вредная черепашка не повреждается селекционный номер Д-6670. На посевах селекционного номера Д-6530 не наблюдалось повреждений хлебной полосатой блошкой, шведской мухой и хлебным жуком-кузькой., Aim. Analysis of pest prevalence and identification of sustainable breeding material of spring durum wheat in the steppe zone of the оrenburg Urals. Materials and methods. Etymological analyses were carried out in a nursery for competitive variety trial according to established methods during the period of 2014-2018. Results. In the conditions of Orenburg steppes spring hard wheat plantings were mostly damaged by Oscinella pusilla, Eurygaster integriceps and Anisoplia austriaca. The research showed that weather conditions during vegetation period of wheat highly influence population of pests and their harmfulness. Colonization of crops by Oscinella pusilla during parasitogenic years reach to 50-60%, while share of damaged plants counts 19-27%. Population of Eurygaster integriceps was at a rate of 2,0-2,1 specimens per 1 square meter, and quantity of damaged plants was 0,67-0,71%. Population of Anisoplia austriaca during milk stage reached to 5-10 specimens per square meter, quantity of damaged plants was 15-30% and damage degree of grain heads was 10-35%. Evaluation of the breeding stock revealed varieties of spring hard wheat resistant to certain pests. Conclusion. Efficiency of breeding operations oriented for adaptability to steppe conditions of the Orenburg region depends on quality of parent material used in hybridization. Varieties of wheat with resistance to biotic environmental stressors are considered as valuable breeding material. High resistance to pests mentioned here is noticed in a selected number D-6501. Cereal striped fleas and corn bugs can’t damage a selective number D-6670. Crops of a selective number D-6530 weren’t damaged by cereal fleas Phyllotreta vittula, Oscinella pusilla and Anisoplia austriaca.

Pasta cooking quality is well known to be related to semolina protein content and composition, however impact of the unextractable polymeric protein content (%UPP) remains disputed. In this work different semolina samples, of variable protein contents (10.5–14.2%) and %UPP (20.2–46.3%) are studied. The changes in %UPP induced by the successive pasta processing steps (mixing, extrusion, drying) but also those occurring during resting periods at 35 °C, applied in-between them, were investigated. Effect of a resting period was moderate after mixing, but pronounced after extrusion. Resting of extruded pasta at 35 °C significantly increased %UPP, which can even grow beyond that of the semolina. No relationship was found between pasta viscoelastic index (VI) and semolina %UPP or protein content. However, cooked pasta VI was found related to the calculated %UPP of rested fresh pasta.

International audience; Cropping system models are powerful tools for regional impact assessment, but their input data requirements for large heterogeneous areas are difficult to fulfil. Hence, the objectives of this paper are to present low-data approaches for specifying detailed management data required by cropping system models, and for calibrating default crop parameters applied to 12 regions in the European Union (EU). Various downscaling and upscaling procedures for different data types are applied to address both objectives. The Agricultural Production and Externalities Simulator (APES) model is used for illustrative purposes. Combining easy-to-collect regional crop management information and expert knowledge enables to develop generic, expert-based rules for specifying crop management. Effects of these expert-based management rules on simulated yields and nitrogen leaching are illustrated using APES. Simulated yields of grain maize, soft wheat and durum wheat using default crop parameters for phenology are compared with crop yields observed in 12 EU regions. The accuracy of the simulated yields was variable, but generally poor. A regional calibration factor Kpheno is developed based on the temperature sum of the average sowing and harvest dates of the three crops in each region. Applying this calibration factor improved the simulated yields in all cases. Results suggest that it is possible to develop expert-based management rules and to capture yield variation across the EU by using the presented low-data approaches.

After 40 years of using different rates and ratios of nitrogen, phosphorus and potassium in a long-term stationary trial, we studied the effects of these treatments on the levels of biogenic macro- and micro-elements in the flag leaf and grain of hard wheat. Our study showed that the treatments had more effect on the levels of said elements in the flag leaf than the grain. Of the three nutrients, nitrogen had the largest influence. The levels of the elements studied were the lowest in the control treatment and the one where only potassium fertilizer had been used. Increasing fertilizer rates of all three nutrients increased to varying degrees the levels of all macro- and micro-elements under study. Nitrogen affected grain yield the most. With the exception of nitrogen, the use of different rates and ratios of N, P and K did not have any major effect on the levels of the elements studied in the grain. The nitrogen content was the smallest in the control treatment nitrogen-free treatments and treatments with the smallest nitrogen rate. In spite of the long-term incorporation of N, P and K, which exceeded the amounts of these elements removed by yield, there was no interaction between the three nutrients and the elements studied. According to the results of our study, even after long-term fertilization with increased N, P and K rates when chernozem has a good supply of phosphorus and potassium and a medium supply of nitrogen, nitrogen will be the element with the largest influence on the grain yield of hard wheat as well as on its chemical composition, as N levels increase in both the flag leaf and grains of this crop. U stacionarnom, dugotrajnom poljskom ogledu posle četiri decenije primene različitih doza i odnosa azota, fosfora i kalijuma, ispitan je njihov uticaj na sadržaj biogenih makro i mikroelemenata, u listu zastavičaru i zrnu. Primena različitih doza i odnosa azota, fosfora i kalijuma u većoj meri je uticala na sadržaj ispitivanih elemenata u listu zastavičaru nego u zrnu. Od ispitivana tri hraniva azot je ispoljio najveći uticaj. Najmanji je bio sadržaj ispitivanih elemenata kod kontrole i varijante kod koje je primenjivano samo kalijumovo đubrivo. Sa povećanjem doza primenjenih hraniva povećao se sadržaj u manjoj ili većoj meri svih ispitivanih elemenata. Azot je u najvećoj meri uticao i na prinos zrna. Primena različitih doza i odnosa azota, fosfora i kalijuma nije ispoljila veći uticaj na sadržaj ispitivanih elemenata u zrnu, osim u slučaju azota. Sadržaj azota bio je najmanji kod kontrole, varijanata kod kojih nisu primenjivana azotna đubriva i pri upotrebi najmanje doze azota. I pored višegodišnje primene doza azota fosfora i kalijuma koje premašuju njihovo iznošenje prinosima nije došlo do interakcije između primenjenih i ispitivanih elemenata. Na osnovu dobijenih rezultata može se zaključiti da na černozemu dobro obezbeđenog u fosforu i kalijumu i osrednje u azotu, i posle višegodišnje primene povećanih doza azota, fosfora i kalijuma najveći uticaj ne samo na prinos zrna već i na hemijski sastav ima azot, povećavajući pre svega njegov sadržaj kako u listu zastavičaru tako i u zrnu.