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The Kazakhstan-Siberia Network for Spring Wheat Improvement (KASIB) was established in 2000, forming a collaboration between breeding and research programs through biannual yield trials. A core set of 142 genotypes from 15 breeding programs was selected, genotyped for 81 DNA functional markers and phenotyped for 10 agronomic traits at three sites in Kazakhstan (Karabalyk, Shortandy and Shagalaly) and one site in Russia (Omsk) in 2020–2022. The study aim was to identify markers demonstrating significant effects on agronomic traits. The average grain yield of individual trials varied from 118 to 569 g/m2. Grain yield was positively associated with the number of days to heading, plant height, number of grains per spike and 1000-kernel weight. Eight DNA markers demonstrated significant effects. The spring-type allele of the Vrn-A1 gene accelerated heading by two days (5.6%) and was present in 80% of the germplasm. The winter allele of the Vrn-A1 gene significantly increased grain yield by 2.7%. The late allele of the earliness marker per se, TaMOT1-D1, delayed development by 1.9% and increased yield by 4.5%. Translocation of 1B.1R was present in 21.8% of the material, which resulted in a 6.2% yield advantage compared to 1B.1B germplasm and a reduction in stem rust severity from 27.6 to 6.6%. The favorable allele of TaGS-D1 increased both kernel weight and yield by 2–3%. Four markers identified in ICARDA germplasm, ISBW2-GY (Kukri_c3243_1065, 3B), ISBW3-BM (TA004946-0577, 1B), ISBW10-SM2 (BS00076246_51, 5A), ISBW11-GY (wsnp_Ex_c12812_20324622, 4A), showed an improved yield in this study of 3–4%. The study recommends simultaneous validation and use of selected markers in KASIB's network. [ABSTRACT FROM AUTHOR]

The Batagay megaslump, a permafrost thaw feature in north-eastern Siberia, provides access to ancient permafrost up to ∼650 kyr old. We aimed to assess the permafrost-locked organic matter (OM) quality and to deduce palaeo-environmental information on glacial–interglacial timescales. We sampled five stratigraphic units exposed on the 55 m high slump headwall and analysed lipid biomarkers (alkanes, fatty acids and alcohols). Our findings revealed similar biogeochemical signatures for the glacial periods: the lower ice complex (Marine Isotope Stage (MIS) 16 or earlier), the lower sand unit (sometime between MIS 16–6) and the upper ice complex (MIS 4–2). The OM in these units has a terrestrial character, and microbial activity was likely limited. Contrarily, the n -alkane and fatty acid distributions differed for the units from interglacial periods: the woody layer (MIS 5), separating the lower sand unit and the upper ice complex, and the Holocene cover (MIS 1), on top of the upper ice complex. The woody layer, marking a permafrost degradation disconformity, contained markers of terrestrial origin (sterols) and high microbial decomposition (iso- and anteiso-fatty acids). In the Holocene cover, biomarkers pointed to wet depositional conditions and we identified branched and cyclic alkanes, which are likely of microbial origin. Higher OM decomposition characterised the interglacial periods. As climate warming will continue permafrost degradation in the Batagay megaslump and in other areas, large amounts of deeply buried ancient OM with variable composition and degradability are mobilised, likely significantly enhancing greenhouse gas emissions from permafrost regions. [ABSTRACT FROM AUTHOR]

Western Siberia is one of the major spring wheat regions of Russia, cultivating over 7 Mha. The objective of the study was to evaluate the variation of macro- and microelements, and of trace metals in four distinct groups of genetic resources: primary synthetics from CIMMYT (37 entries), primary synthetics from Japan (8), US hard red spring wheat cultivars (14), and material from the Kazakhstan–Siberian Network on Spring Wheat Improvement (KASIB) (74). The experiment was conducted at Omsk State Agrarian University, using a random complete block design with four replicates in 2017 and 2018. Concentrations of 15 elements were included in the analysis: macroelements, Ca, K, Mg, P, and S; microelements, Fe, Cu, Mn, and Zn; toxic trace elements, Cd, Co, Ni; and trace elements, Mo, Rb, and Sr. Protein content was found to be positively correlated with the concentrations of 11 of the elements in one or both years. Multiple regression was used to adjust the concentration of each element, based on significant correlations with agronomic traits and macroelements. All 15 elements were evaluated for their suitability for genetic enhancement, considering phenotypic variation, their share of the genetic component in this variation, as well as the dependence of the element concentration on other traits. Three trace elements (Sr, Mo, and Co) were identified as traits that were relatively easy to enhance through breeding. These were followed by Ca, Cd, Rb, and K. The important biofortification elements Mn and Zn were among the traits that were difficult to enhance genetically. The CIMMYT and Japanese synthetics had significantly higher concentrations of K and Sr, compared to the local check. The Japanese synthetics also had the highest concentrations of Ca, S, Cd, and Mo. The US cultivars had concentrations of Ca as high as the Japanese synthetics, and the highest concentrations of Mg and Fe. KASIB's germplasm had near-average values for most elements. Superior germplasm, with high macro- and microelement concentrations and low trace-element concentrations, was found in all groups of material included. [ABSTRACT FROM AUTHOR]

Exploiting genetically diverse lines to identify genes for improving crop performance is needed to ensure global food security. A genome-wide association study (GWAS) was conducted using 46,268 SNP markers on a diverse panel of 143 hexaploid bread and synthetic wheat to identify potential genes/genomic regions controlling agronomic performance (yield and 26 yield-related traits), disease resistance, and grain quality traits. From phenotypic evaluation, we found large genetic variation among the 35 traits and recommended five lines having a high yield, better quality, and multiple disease resistance for direct use in a breeding program. From a GWAS, we identified a total of 243 significant marker-trait associations (MTAs) for 35 traits that explained up to 25% of the phenotypic variance. Of these, 120 MTAs have not been reported in the literature and are potentially novel MTAs. In silico gene annotation analysis identified 116 MTAs within genes and of which, 21 MTAs were annotated as a missense variant. Furthermore, we were able to identify 23 co-located multi-trait MTAs that were also phenotypically correlated to each other, showing the possibility of simultaneous improvement of these traits. Additionally, most of the co-located MTAs were within genes. We have provided genomic fingerprinting for significant markers with favorable and unfavorable alleles in the diverse set of lines for developing elite breeding lines from useful trait-integration. The results from this study provided a further understanding of genetically complex traits and would facilitate the use of diverse wheat accessions for improving multiple traits in an elite wheat breeding program. [ABSTRACT FROM AUTHOR]

Retrogressive thaw slumps (RTS) are an important landform of rapid permafrost degradation in regions with very high ground ice contents. RTS mobilize significant amounts of sediment, meltwater and organic carbon and impact downstream hydrological systems by directly affecting topography and water quality. The term megaslump has previously been coined for RTS exceeding 20 ha in size. The Batagay megaslump in the Yana highlands of NE Siberia with an area of 87.6 ha (in 2023, including the bowl-shaped part and the erosional outlet) has been identified as the largest megaslump on Earth. We use very high resolution remote sensing from satellite data and drones, geological structure modeling, and field data to assess how much and what material is thawed and mobilized in the Batagay megaslump. The total volume of permafrost thaw and material loss from the Batagay RTS amounts to about 1 million m3 per year. The material is by one third composed of thawed sediments and by two thirds of melted ground ice. About 4000 to 5000 tons of previously permafrost-locked organic carbon is released every year. Organic carbon content has been measured as Total Organic Carbon (TOC) of sediments and as Dissolved Organic Carbon (DOC) of ground ice. From its formation in the 1970s until 2023, the Batagay RTS – due to thermal denudation and headwalls retreat – mobilized a total volume of about 34.7 million m3 of which 23.4 million m3 were melted ground ice and 11.3 million m3 were thawed deposits including a total of about 169,500 t organic carbon. With these rates of sediment and carbon mobilization, the Batagay megaslump is not only a prominent local feature of rapid permafrost thaw, but offers excellent conditions to study rates and mechanisms of rapid permafrost degradations and to calculate the stock and release of, e.g., organic matter. • 3D geological modeling allowed estimating the Batagay megaslump material flux. • The megaslump mobilized ca. 35 million m3 since initiation in the 1990s. • Since 2014, the annual mobilized volume amounts to ca. 1 million m3/year. • About ⅔ of the total material volume was ground ice and ⅓ was permafrost sediments. • Organic carbon release amounts to 4000 to 5000 tons per year. [ABSTRACT FROM AUTHOR]