Raise and characterization of a bread wheat hybrid line (Tulaykovskaya 10 × Saratovskaya 29) with chromosome 6Agi2 introgressed from Thinopyrum intermedium

Wheatgrass Thinopyrum intermedium is a source of agronomically valuable traits for common wheat. Partial wheat–wheatgrass amphidiploids and lines with wheatgrass chromosome substitutions are extensively used as intermediates in breeding programs. Line Agis 1 (6Agi2/6D) is present in the cultivar Tulaykovskaya 10 pedigree. Wheatgrass chromosome 6Agi2 carries multiple resistance to fungal diseases in various ecogeographical zones. In this work, we studied the transfer of chromosome 6Agi2 in hybrid populations Saratovskaya 29×Tulaykovskaya 10 (S29×T10) and Tulaykovskaya 10×Saratovskaya 29 (T10×S29). Chromosome 6Agi2 was identified by PCR with chromosome-specific primers and by genomic in situ hybridization (GISH). According to molecular data, 6Agi2 was transmitted to nearly half of the plants tested in the F2 and F3 generations. A new breeding line 49-14 (2n = 42) with chromosome pair 6Agi2 was isolated and characterized in T10×S29 F5 by GISH. According to the results of our field experiment in 2020, the line had high productivity traits. The grain weights per plant (10.04±0.93 g) and the number of grains per plant (259.36±22.49) did not differ significantly from the parent varieties. The number of grains per spikelet in the main spike was significantly higher than in S29 (p ≤ 0.001) or T10 (p ≤ 0.05). Plants were characterized by the ability to set 3.77±0.1 grains per spikelet, and this trait varied among individuals from 2.93 to 4.62. The grain protein content was 17.91 %, and the gluten content, 40.55 %. According to the screening for fungal disease resistance carried out in the field in 2018 and 2020, chromosome 6Agi2 makes plants retain immunity to the West Siberian population of brown rust and to dominant races of stem rust. It also provides medium resistant and medium susceptible types of response to yellow rust. The possibility of using lines/varieties of bread wheat with wheatgrass chromosomes 6Agi2 in breeding in order to increase protein content in the grain, to confer resistance to leaf diseases on plants and to create multiflowered forms is discussed.

Review and analysis of technologies for harvesting perennial grain crops

In agriculture, according to the data of the statistical collection, the production of grain crops occupies a large part. At the moment, much attention is paid to the study of perennial crops such as Thinopyrum intermedium and Trititrigia cziczinii Tsvelev. These crops help to: slow down soil erosion, protect water resources, and minimize the leaching of nutrients [1,2]. The non-cereal part of the crop is a significant reserve for strengthening the fodder base of animal husbandry, expanding the range of sources of raw materials for the microbiological industry in the production of fodder proteins. The article provides an overview of technologies and equipment for harvesting grain crops, on the basis of which one of the optimal harvesting method for perennial crops is distinguished - stripping. Based on the results of the literature review, the main technologies used for harvesting grain crops were identified: direct and indirect singlephase and two-phase combine harvesting technologies; one-, two- or three-phase non-combine harvesting technologies including the “neveika” method; standing stripping technology. The purpose of this article is to review existing harvesting technologies and equipment, selection of the optimal harvesting technology for perennial crops such as Trititrigia cziczinii Tsvelev and Thinopyrum intermedium.

The Perennial Grain Crop Thinopyrum intermedium (Host) Barkworth & D.R. Dewey (Kernza™) as an Element in Crop Rotations: A Pilot Study on Termination Strategies and Pre-Crop Effects on a Subsequent Root Vegetable

Intermediate wheatgrass (IWG) may benefit soil fertility in crop rotations. To investigate termination strategies, i.e., autumn ploughing (AP), autumn harrowing (AH) and spring harrowing (SH) on a five-year-old IWG stand, a pilot study was performed. After the treatments, beetroots were sown and the IWG plants were counted twice during the beetroot growing season. The number of IWG plants was highest (20) after the SH strategy, intermediate (14) after the AH, and lowest (3) after the conventional termination strategy, AP. After the first plant count, the plots were subject to mechanical weeding in the form of a stale seedbed (i.e., harrowing twice before sowing). At beetroot harvest, the number of IWG plants was low (3 in SH and AH, 0 in AP) and similar between the treatments. The beetroot production was highest after AP and lowest in SH, and intermediary in AH, which showed no difference from AP and SH. At beetroot harvest, the weed biomass did not differ between the termination strategies. The weeds were mainly annuals. There were no differences in soil bulk density between termination strategies. Our results show that shallow soil tillage is enough to terminate IWG, as long as it repeated. We suggest further studies that investigate the dynamics of crop sequences with IWG, and how to benefit from this crop in rotations.

Cytogenetic identification and molecular marker development for the novel stripe rust-resistant wheat–Thinopyrum intermedium translocation line WTT11

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat (Triticum aestivum L.) worldwide. Xiaoyan 78829, a partial amphidiploid developed by crossing common wheat with Thinopyrum intermedium, is immune to wheat stripe rust. To transfer the resistance gene of this excellent germplasm resource to wheat, the translocation line WTT11 was produced by pollen irradiation and assessed for immunity to stripe rust races CYR32, CYR33 and CYR34. A novel stripe rust-resistance locus derived from Th. intermedium was confirmed by linkage and diagnostic marker analyses. Molecular cytogenetic analyses revealed that WTT11 carries a TTh·2DL translocation. The breakpoint of 1B was located at 95.5 MB, and the alien segments were found to be homoeologous to wheat-group chromosomes 6 and 7 according to a wheat660K single-nucleotide polymorphism (SNP) array analysis. Ten previously developed PCR-based markers were confirmed to rapidly trace the alien segments of WTT11, and 20 kompetitive allele-specific PCR (KASP) markers were developed to enable genotyping of Th. intermedium and common wheat. Evaluation of agronomic traits in two consecutive crop seasons uncovered some favorable agronomic traits in WTT11, such as lower plant height and longer main panicles, that may be applicable to wheat improvement. As a novel genetic resource, the new resistance locus may be useful for wheat disease-resistance breeding.