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The southwestern regions of the Kingdom of Saudi Arabia (KSA) are geographically and agriculturally diverse. Over millennia, crop production in these regions has evolved to use renewable water resources sustainably. This study analysed environmental and crop production data for 58 governorates in KSA’s four southwestern regions: Al Baha, Aseer, Jazan and Makkah. The biplot analysis generated six clusters of cropping systems: sorghum, cereals, dates, watermelon, vegetables and fruits, and mixed. The main biophysical factors shaping these systems are topography, altitude, rainfall, air temperature and soils. Sorghum, grown on more than half of the cultivated land, dominates the two main systems. Fruits (subtropical and temperate) and open field vegetables are important elements in most systems. The main challenge is combining a moderate use of water with greater crop diversity. Cereals consume relatively little water, but their dominance within the systems reduces overall diversity. Another important issue is the low-input technologies used to cultivate sorghum and other cereals. Landraces or older varieties are planted and little, if any, fertilizers and pesticides are applied. The introduction of sustainable intensification packages is needed, which can begin with making improved varieties accessible to farmers, promoting conservation agriculture, and integrated pest management practices.

Kazakhstan–Siberian Network on Spring Wheat Improvement unites 18 spring wheat (Triticum aestivum L.) research and breeding programs and presents opportunities to study genotype × environment interactions. Trial data from six locations in Kazakhstan and Russia in 2017–18 were used for grain ionomics analysis to evaluate the relative contributions of environment and genotype to variation in elemental composition and to formulate a methodology to enhance concentrations of important minerals in grain. The effect of year was least important to variation. For several elements (P, S, Cu, Mn and Mo), the effect of site was 2–3 times higher than the effect of genotype. The effects of genotype and site were similar for Ca, Mg, Fe, Cd and Sr concentration. Average broad-sense heritability across six sites in both years was: (for macroelements) Mg 0.59 > Ca 0.50 > K 0.44 > P 0.30 > S 0.20; and (for microelements) Zn 0.44 > Mn 0.41 > Cu 0.40 > Fe 0.38. Biplot analysis grouped the traits into five clusters: (1) concentrations of Co, Cu, Mo and Sr; (2) concentrations of Mg, P and Zn; (3) concentrations of K and Ni; (4) protein content, concentrations of Cd, Fe, Mn and S; and (5) grain yield, concentrations of Ca and Rb. These associations reflect regional soil and environment variation independent of genotype. Protein content had positive and significant genotypic correlations with Mg (0.57), P (0.60), S (0.68), Fe (0.64), Cu (0.50), Mn (0.50) and Zn (0.53). A combination of high grain yield, relatively high protein content, and high concentrations of P, S, Mn, Cu and Zn (singly or combined) was identified in the genotypes Element-22 (check cultivar), Lutescens-3-04-21-11, and Silach. The study contributes to research and cultivar development to improve the nutritional profile of grain for consumers.

Collection of wheat landraces (WLR) was conducted in Afghanistan, Iran, and Turkey in 2010–2014. A representative subset of this collection was used in the current study and included 45 bread wheat landraces from Turkey, 19 from Iran, and 20 from Afghanistan. This material was supplemented by 73 modern cultivars and breeding lines adapted to semiarid conditions and irrigated conditions. Overall, 157 genotypes were tested in Turkey in 2018 and 2019 and in Afghanistan and Iran in 2019 under rainfed conditions to compare performance of WLR and modern material. The germplasm was genotyped using a high density Illumina Infinium 25K wheat SNP array and KASP markers for agronomic traits. The average grain yield ranged between 2.2 and 4.0 t/ha depending on the site and year. Three groups of landraces demonstrated similar average grain yield, though Afghanistan material was slightly higher yielding not only in Afghanistan but also in Turkey. Modern material outyielded the landraces in two environments out of four. The highest yielding landraces were competitive with the best modern germplasm. Frequency of gene Sus2-2B affecting 1000 kernel weight was 64% in WLR and only 3% in modern material. Presence of positive allele of Sus2-2B increased 1000 kernel weight by nearly 4%. Breeding strategy to improved landraces and modern cultivars is discussed.

An SNP analysis is performed using the iSelect90K SNP array to identify the genetic diversity of synthetic hexaploid wheat lines of Kyoto University (Japan) bred by crossing durum wheat variety Langdon (Triticum durum, 2n = 4x = 28, BBAA) with accessions of Aegilops tauschii (2n = 2x = 14, DD) of different ecological origin. The level of genomic variability is calculated by using the Emma approach (Efficient Mixed-Model Association) and genomic relationship matrix (G). The genetic diversity of the genome D of synthetic lines is greater than that of genomes A and B by 50%. The greatest genetic polymorphism is observed in the line Langdon/Ku-2105 from Pahlavi province on the southern coast of Caspian Sea and the line Langdon/Ig 131606 from Kyrgyzstan. Lines from India (Langdon/Ig 48042), Iranian provinces Sari and Babolsar (Langdon/Ku-2088, Langdon/Ku-2093, Langdon/Ku-2096), and Turkmenistan (Langdon/Ig 26387) are characterized by a lower genetic diversity of the genome D. Thus, the involvement of synthetic hexaploid wheat on the basis of Ae. tauschii accessions from the Caspian basin into hybridization will extend the genetic diversity of wheat varieties and increase the efficiency of genetic resources.

Spring wheat is produced in Kazakhstan and Western Siberia on a large area exceeding 16 mln ha. The crop grows during the short season from May till September in the extensive production system. Th...

In recent years, intensified development of stem rust of wheat has again been noted in the grain-growing regions of Kazakhstan. To determine the genetic basis of immunity in 2015 – 2019, the authors performed targeted studies in the conditions of the southeast and north of Kazakhstan on the natural and the artificially infectious backgrounds of inoculation. Their scientific novelty consisted in identifying effective Sr genes of wheat resistance to the Kazakhstan population of stem rust. The obtained results of the immunological assessment of the trap varieties show that most studied genotypes with the Sr genes were susceptible to the Kazakhstan population of stem rust. With that, the varieties carrying the Sr31 gene have been affected to varying degrees. It should be especially noted that the Sr31 gene in combination with the Sr24 gene ensured more reliable protection from the population of the stem rust pathogen. The authors have selected the obtained resistance genes by their efficiency: Sr2 complex; Sr11; Sr21; Sr31; Sr36; Sr39; Sr40, SrSatu; SrNin, as well as combinations of the Sr24 and 1RS-Am genes; Sr24.31; Sr6.31.21; Sr6,24,36,1RSAm; Sr7a, Sr12, Sr6; and Sr31 absent. The authors recommend them as sources of resistance to the local stem rust population.

Stem rust in recent years has acquired an epiphytotic character, causing significant economic damage for wheat production in some parts of Western Siberia. On the basis of a race composition study of the stem rust populations collected in 2016-2017 in Omsk region and Altai Krai, 13 pathotypes in Omsk population and 10 in Altai population were identified. The race differentiation of stem rust using a tester set of 20 North American Sr genes differentiator lines was carried out. The genes of stem rust pathotypes of the Omsk population are avirulent only to the resistance gene Sr31, Altai isolates are avirulent not only to Sr31, but also to Sr24, and Sr30. A low frequency of virulence (10-25 %) of the Omsk population pathotypes was found for Sr11, Sr24, Sr30, and for Altai population - Sr7b, Sr9b, Sr11, SrTmp, which are ineffective in Omsk region. Field evaluations of resistance to stem rust were made in 2016-2018 in Omsk region in the varieties and spring wheat lines from three different sources. The first set included 58 lines and spring bread wheat varieties with identified Sr genes - the so-called trap nursery (ISRTN - International Stem Rust Trap Nursery). The second set included spring wheat lines from the Arsenal collection, that were previously selected according to a complex of economically valuable traits, with genes for resistance to stem rust, including genes introgressed into the common wheat genome from wild cereal species. The third set included spring bread wheat varieties created in the Omsk State Agrarian University within the framework of a shuttle breeding program, with a synthetic wheat with the Ae. tauschii genome in their pedigrees. It was established that the resistance genes Sr31, Sr40, Sr2 complex are effective against stem rust in the conditions of Western Siberia. The following sources with effective Sr genes were selected: (Benno)/6*LMPG-6 DK42, Seri 82, Cham 10, Bacanora (Sr31), RL 6087 Dyck (Sr40), Amigo (Sr24, 1RS-Am), Siouxland (Sr24, Sr31), Roughrider (Sr6, Sr36), Sisson (Sr6, Sr31, Sr36), and Fleming (Sr6, Sr24, Sr36, 1RS-Am), Pavon 76 (Sr2 complex) from the ISRTN nursery; No. 1 BC1F2 (96 × 113) × 145 × 113 (Sr2, Sr36, Sr44), No. 14а F3 (96 × 113) × 145 (Sr36, Sr44), No. 19 BC2F3 (96 × 113) × 113 (Sr2, Sr36, Sr44), and No. 20 F3 (96 × 113) × 145 (Sr2, Sr36, Sr40, Sr44) from the Arsenal collection; and the Omsk State Agrarian University varieties Element 22 (Sr31, Sr35), Lutescens 27-12, Lutescens 87-12 (Sr23, Sr36), Lutescens 70-13, and Lutescens 87-13 (Sr23, Sr31, Sr36). These sources are recommended for inclusion in the breeding process for developing stem rust resistant varieties in the region.Стеблевая ржавчина пшеницы в последние годы приобрела эпифитотийный характер, нанося значительный экономический ущерб производству зерна пшеницы в отдельных областях Западной Сибири. По результатам изучения расового состава популяций стеблевой ржавчины, собранной в 2016–2017 гг. в Омской области и Алтайском крае, выявлено 13 патотипов в омской популяции и 10 – в алтайской. Диффе- ренцирование рас стеблевой ржавчины проводили с помощью тестерного набора 20 североамериканских линий-дифференциаторов Sr генов. Гены патотипов стеблевой ржавчины омской популяции авирулентны только к гену устойчивости Sr31, алтайские изоляты авирулентны, помимо Sr31, к генам Sr24, Sr30. Низкая частота вирулентности (10–25 %) патотипов омской популяции установлена для Sr11, Sr24, Sr30, а патотипов алтайской – для Sr7b, Sr9b, Sr11, SrTmp, которые неэффективны в Омской области. Полевая оценка устойчивости к стеблевой ржавчине проводилась в 2016–2018 гг. в Омской области в динамике в течение вегетационного периода у сортов и линий мягкой пшеницы из трех различных источников. Первый набор включал 58 линий и сортов яровой мягкой пшеницы с идентифицированными генами Sr, условно называемыми «питомник- ловушка» (ISRTN – international stem rust trap nursery). Второй набор включал линии яровой пшеницы из коллекции «Арсенал», отобранные ранее по комплексу хозяйственно ценных признаков и несущие пирамиду генов устойчивости к стеблевой ржавчине, в том числе интрогрессированных в геном мягкой пшеницы от дикорастущих видов злаков. Третий набор включал сорта яровой мягкой пшеницы, созданные в Омском аграрном университете по программе челночной селекции, имеющие в родословной синтетическую пшеницу с геномом Ae. tauschii. Установлено, что линии с генами Sr31, Sr40, Sr2 complex невосприимчивы к стеблевой ржавчине в условиях Западно-Сибирского региона. Выделены источники с эффективными гена- ми Sr : из питомника ISRTN – (Benno)/6*LMPG-6 DK42 (Sr31), Seri 82 (Sr31), Cham 10 (Sr31), Bacanora (Sr31), RL 6087 Dyck (Sr40), Amigo (Sr24, 1RS-Am), Siouxland (Sr24, Sr31), Roughrider (Sr6, Sr36), Sisson (Sr6, Sr31, Sr36), Fleming (Sr6, Sr24, Sr36, 1RS-Am), Pavon 76 (Sr2 complex); из коллекции «Арсенал» – № 1 BC1F2 (96 × 113) × 145 × 113 (Sr2, Sr36, Sr44), № 14а F3 (96 × 113) × 145 (Sr36, Sr44), № 19 BC2F3 (96 × 113) × 113 (Sr2, Sr36, Sr44), № 20 F3 (96 × 113) × 145 (Sr2, Sr36, Sr40, Sr44); сорта Омского аграрного университета – Элемент 22 (Sr31, Sr35), Лютесценс 27-12, Лютес- ценс 87-12 (Sr23, Sr36), Лютесценс 70-13, Лютесценс 87- 13 (Sr23, Sr31, Sr36). Выделенные источники рекомен- дуются для включения в селекционный процесс при создании сортов, устойчивых к стеблевой ржавчине в условиях региона.

Plant-parasitic nematodes (PPNs) are considered serious damaging on the global cereals production systems. The current study was conducted to evaluate the incidence of PPNs in the main cereal-growing areas in northern Kazakhstan. PPNs were detected in about 90% of 78 soil samples and thirteen genera were identified, including Pratylenchus, Heterodera, Geocenamus, Ditylenchus, Helicotylenchus, Rotylenchus, Pratylenchoides, and Tylenchorhynchus. Out of the 78 samples, 32 samples were found infested by Heterodera filipjevi based on the morphological and molecular analysis. To our knowledge, this is the first report on this cereal cyst nematode species in northern Kazakhstan. During the morphological and molecular assays, intraspecific polymorphism was observed within H. filipjevi populations and the populations divided into at least two groups. The highest frequency of infestation of H. filipjevi (76%) was recorded from Kokshetau Province when compared to other provinces: Astana (50%), Petropavl (37%), and Kostanay (16%). The highest number of cysts (30.4) was found among Astana samples while the lowest number of cysts (18.2) was recorded from Kostanay samples. Cyst nematodes can maintain their population above the economic threshold as stimulated by the cereal monoculture system (mainly wheat) which is similar to the cereal production systems of northern Kazakhstan.

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.

Spring durum wheat (Triticum durum) is an important crop in Russia and Kazakhstan. There are substantial yield losses due to fungal diseases. The research focused on host plant resistance to fungal diseases, and identification of the sources of multiple resistance which can be deployed in durum wheat breeding programs. Extensive environmental varietal testing experiments at places with diverse meteorological factors allows the selection of valuable material. In 2017 and 2018, a collection of 21 spring durum wheat accessions from the Kazakhstan-Siberian Network for Wheat Improvement (KASIB) was studied under high disease pressure. The following diseases were evaluated in three regions of Russia (Omsk, Altai and Samara), in Southern Kazakhstan and in Kenya: leaf, stem and yellow rusts, powdery mildew, glume blotch, tan spot and spot blotch. As the result, three breeding lines with multiple disease resistance to three rust species, powdery mildew and leaf blotches were identified: Hordeiforme 178-05-02, Hordeiforme 05-42-12 and Hordeiforme 1591-21. Furthermore, the accessions resistant to rusts or spots were also identified. Phytopathological studies and molecular marker analysis showed absence of genes Lr1, Lr3, Lr9, Lr10, Lr19/Sr25, Lr20/Sr15, Lr24/Sr24, Lr26/Sr31/Yr9/Pm8, Lr34/Sr57/Yr18 and Lr37/Sr38/Yr17. Clustering of durum wheat accessions based on similarity in resistance and susceptibility revealed three main groups; accessions susceptible to all three rusts, those with some resistance to one or two rusts, and those with seedling resistance to leaf rust only.

Recurrent selection and intercrossing between best of the best parents in each generation of breeding cycle resulted in a narrower genetic diversity in elite wheat (Triticum aestivum L.) germplasm. Therefore, we investigated diverse source of 143 synthetic and bread wheat accessions for identifying potentially rich genetic resources for improving the genetic diversity in wheat. This study identified 47,526 genotyping-by-sequencing-derived SNP markers that were nearly evenly distributed across three genomes of wheat. The population structure analysis identified three distinct clusters (Japan synthetics, CIMMYT synthetics, and bread wheat) of wheat genotypes on the basis of type and geographical origin of wheat accessions. Population differentiation using analysis of molecular variance indicated 21% of the total genetic variance among subgroups and the remainder within subgroups. This study also identified that the Japan synthetic group was the most divergent group compared with other subgroups. The genetic diversity comparisons between synthetic and bread wheat lines showed that the gene diversity of synthetic wheat was 33% higher than bread wheat accessions, indicating the potential use of these lines for broadening the genetic diversity of modern wheat cultivars. The results from this study will be helpful in further understanding genomic features of wheat and facilitate their use in wheat breeding programs.

Tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease of wheat in Kazakhstan. This study evaluated 103 winter wheat genotypes for tan spot resistance and high-productivity traits in the field in two years. Entries were also characterized using the molecular marker Xfcp623, indicative of Tsn1 gene conferring sensitivity to Ptr ToxA. The proportion of entries insensitive to Ptr ToxA was relatively high (71%). Forty-eight entries with the lowest tan spot severity in the field were confirmed to be insensitivity to Ptr ToxA in the molecular screening. Entries which were resistant under field conditions had similar level of seedling resistance. Principal component analysis biplots showed, that all spike productivity traits were highly correlated. Days to heading (DH) and tan spot severity, as well as the normalized difference vegetation index and DH were strongly correlated. Thousand kernels weight (TKW) and plant height were highly correlated and both were negatively correlated with DH and tan spot severity, indicating that taller cultivars tended to be more resistant. The Xfcp623 negative entries had lower disease severity (by about 40%), flowered up to 2 days later than entries with Tsn1 and had significantly more spikelets per spike, number of grains per spike, TKW and grain weight/spike. The results of the study will be important for increasing the efficiency of breeding based on the elimination of the genotypes with dominant allele Tsn1. Of the 103 entries evaluated, 28 can be directly used in breeding programs to improve tan spot resistance and productivity of winter wheat.

Development of new wheat cultivars combining good local adaptation, disease resistance and grain quality represents an important strategy component for national food security. Uzbekistan was identified by N. Vavilov as important center of wheat diversity. An inventory of landraces was conducted in 2010–2013 in western Tien-Shan Mountains to survey, collect, and characterize old wheats still grown by farmers. Thirty landraces were collected from 17 villages in Jizzakh, Kashkadarya and Surkhandarya Regions. The material went through spike selection, head-rows, un-replicated trials in Tashkent, Uzbekistan (2012–2015), and replicated trials in Konya, Turkey (2018–2019). Landrace diversity was described using spike morphological traits and DNA profiles as reflected by single nucleotide polymorphism. A socioeconomic survey demonstrated that wheat landraces are grown in remote mountain communities by subsistence farmers despite having access to modern cultivars, and both are frequently grown together. The main reasons for the maintenance of landraces are: (1) large grain with excellent bread-making quality and suitability for home-baking; (2) specific adaptations allowing stable and reliable yield; and (3) straw yield and quality. Similar genomic profiles shared by some landraces from remote regions of Uzbekistan and neighboring Tajikistan demonstrated their common origin and are indicative of seed exchange between farmers. Agronomic characterization demonstrated the resilient nature of their adaptation based on spring and facultative growth habit and superiority of some landraces for grain yield and its components compared to local checks. Viable options for maintaining and expanding on-farm wheat diversity include their improvement through selection and breeding, market development, variable incentives, and capacity building. For the first time, this paper presents results of a unique 10-year study in Uzbekistan on social conditions in the areas where wheat landraces are grown, analyses the diversity of these landraces, evaluates agronomic characteristics, and discusses the sustainability options for on-farm wheat landraces use and conservation.

The authors would like to thank CIMMYT and the Research and Development Unit (BAP) of Bolu Abant Izzet Baysal University for funding this study. Kazakhstan is one of the biggest wheat producers, however, its wheat production is far below the average international wheat production standard due to biotic and abiotic stressors. Plant-parasitic nematodes are devastating for cereal production systems worldwide. A comprehensive survey was conducted in 2019 to identify plant-parasitic nematodes associated with wheat in different locations of central, eastern, and southeastern Kazakhstan. The results revealed 33 root-lesion and 27 cyst nematode populations from the 77 localities sampled. These two genera occurred in separate or in mixed populations. The root-lesion populations were identified as Pratylenchus neglectus and P. thornei while all cyst nematodes were identified as Heterodera filipjevi. The identification of nematodes was firstly performed based on morphological and morphometric features and confirmed by BLAST and phylogenetic analyses based on the internal transcribed spacer and the D2-D3 expansion located in the 28S gene of ribosomal DNA for CCN and RLN populations, respectively. Pratylenchus neglectus and P. thornei populations from Kazakhstan showed a high similarity with the American, European, and Asian populations. Heterodera filipjevi populations formed a well-supported cluster with the corresponding populations from different countries and showed a slightly intraspecific polymorphism. Kazakhstan populations of H. filipjevi may have multiple introductions in Kazakhstan due to the divergence among them. The results of this study are of great importance for breeding programs and will enable awareness for extension advisors to develop measures to control these nematodes in cereal cropping areas in Kazakhstan. CIMMYT; Research and Development Unit (BAP) of Bolu Abant Izzet Baysal University

Triticale (×Triticosecale Wittmack) is obtained from wheat × rye crossing. It is positioned between wheat and rye in terms of resistance to soilborne pathogens including Gaeumannomyces graminis var. tritici, Fusarium culmorum, F. avenaceum, and Bipolaris sorokiniana (Arseniuk and Goral 2015). In 2019, seven triticale fields were surveyed in Almaty Province, Kazakhstan to examine soil-borne fungal pathogens. A total of 28 symptomatic plants with stunting, rot or discolored root were collected to identify causal agents. The overall disease incidence was approximately 8 to 10% in the fields. Fungi were isolated from 3-5 mm pieces excised from symptomatic tissues. The pieces were exposed to surface disinfection in 1% sodium hypochlorite solution for 2 min, rinsed three times with sterile distilled water, blotted dry, and plated on 1/5 strength potato dextrose agar (PDA) amended with 0.01% streptomycin. Plates were left in the dark at 23°C for 7 days. A total of 34 fungal colonies were isolated of which nineteen isolates, originally from six fields showed the cultural characteristics of B. sorokiniana. This species was previously reported to cause common root rot on triticale in Kazakhstan (Ozer et al. 2020). Ten isolates from four fields produced pale orange and cottony mycelium with red pigmentation on the agar, which is typical of Fusarium-like growth. The remaining isolates (n=5) from two fields produced salmon-colored and scarce aerial mycelium with no soluble pigmentation, similar to Microdochium spp. Fusarium isolates produced thick-walled and curved macroconidia with 3-4 septa (n=50, 25.7 to 37.6 × 4.1 to 7.3 μm in size) and notched basal cell on PDA, but microconidia were absent, which matches the description of F. culmorum (Wm.G. Sm.) Sacc. (Leslie and Summerell 2006). Microdochium isolates produced swollen, brown, and thick-walled chlamydospores and hyaline, one-celled, and thin-walled conidia (n=50, 5.4 to 9.3 × 1.5 to 3.0 μm in size) formed on ampullate and cylindrical conidiogenous cells on oatmeal agar (OA). These morphological features are consistent with previous observations for Microdochium bolleyi (R. Sprague) de Hoog & Herm.-Nijh. (Hong et al. 2008). To confirm morphological preliminary identifications, the portion of the translation elongation factor 1-alpha (EF1-α) gene was amplified with EF1/EF2 primers (O'Donnell et al. 1998) for representative Fusarium isolates (n=4) for each field. Additionally, the internal transcribed spacer (ITS) of ribosomal DNA was amplified with ITS1/ITS4 primers (White et al. 1990) for representative Microdochium isolates (n=2) for each field. BLASTn queries against NCBI GenBank revealed that the EF1-α sequences of Fusarium isolates (MW311081-MW311084) shared 100% identity with F. culmorum strain CBS 110262 (KT008433). The ITS sequences of M. bolleyi isolates (MW301448-MW301449) matched that of M. bolleyi strain CBS 137.64 (AM502264) with 100% sequence similarity. Pathogenicity test was conducted on pregerminated seeds of triticale cv. Balausa. A plastic pot (17 cm height, 9 cm in diam) was filled with a sterile mixture of vermiculite, peat, and soil (1:1:1, v/v/v). Mycelial plugs (1 cm in diam) were cut from the margin of a growing culture of representative isolates (Kaz_Fus123 and Kaz_Mb01) and placed onto the mixture in the pot. A sterile agar plug was employed as a control treatment. One pregerminated seed was put on the plug and covered with the mixture. The pots were transferred to a growth chamber set at 23 ± 2°C and a photoperiod of 14 hours. The experiment was performed twice using 5 replication pots per isolate. Four weeks after inoculation, discoloration of the crown was observed on all the inoculated roots, whereas no symptoms were observed on the control plants. Koch's postulates were fulfilled by reisolating and identifying the pathogen based on the morphology described above. This is the first report of M. bolleyi and F. culmorum causing root rot on triticale in Kazakhstan. Although B. sorokiniana is the most primary pathogen that may limit yield in the production of triticale in Kazakhstan, F. culmorum and M. bolleyi have been found to be less frequent and less aggressive pathogens, respectively. Further studies are needed to better understand the potential distribution and impact of these pathogens on triticale.

Kazakhstan-Siberia Network for Spring Wheat Improvement (KASIB) was established in 2000 to conduct multi-location cooperative yield trials for the exchange of breeding material and to evaluate agronomic traits such as grain yield and disease resistance. In 2016, aggregated KASIB data were analyzed and 120 cultivars and breeding lines demonstrating different degrees of resistance to leaf rust selected. They were tested for leaf rust and agronomic traits in Omsk, Russia; Almaty, Kazakhstan and Sakarya, Turkey in 2017–2019. This germplasm was grouped into four categories based on leaf rust reaction: 31 resistant (R), 27 moderately resistant (MR), 37 intermediate (M) and 25 moderately susceptible (MS) entries. Lr genes were postulated based on tests using pathotypes with known virulence profiles and molecular markers. The most frequent Lr genes alone or in combination were Lr10 (31 entries), Lr26 (24), Lr9 (23), Lr1 (18), Lr17 (11), Lr34 (11) and Lr19 (7). Genes Lr1, Lr9, Lr10 and Lr17 reduced the leaf rust severity to M or MS across environments. The presence of Lr26 alone or in combination with other major genes reduced the leaf rust severity to MR-M in Omsk and R in Sakarya. The only gene with the large effect on leaf rust was Lr19, which provided a high level of resistance at all sites both alone and in combination with Lr26. Leaf rust severity in 52 entries with adult plant resistance (APR) was compared to 68 entries possessing effective seedling resistance genes. The leaf rust severity in entries with APR compared to seedling resistance was similar at low infection pressure at Sakarya, 2018 and Omsk, 2019. However, at higher leaf rust infection pressure at Omsk in 2017 and 2018, Almaty in 2019, there was a clear advantage for the germplasm possessing major genes. High level of stem rust infection in Omsk in 2019 confirmed effectiveness of the Sr31/Lr26 gene. A set of 33 genotypes was selected combining resistance to leaf and stem rust with superior agronomic performance.

We developed and validated high-throughput Kompetitive Allele-Specific PCR (KASP) assays for key genes underpinning bread-making quality, including the wbm gene on chromosome 7AL and over-expressed glutenin Bx7OE (Glu-B1al) gene. Additionally, we used pre-existing KASP assay for Sec1 (1B.1R translocation) gene on chromosome 1B. The newly developed KASP assays were compared with gel-based markers for reliability and phenotypically validated in a diversity panel for Mixograph, Rapid Visco Analyzer (RVA) and Mixolab traits. Genotypes carrying the 1B.1R translocation had significantly lower Mixolab parameters than those without the translocation. Similarly, superior effects of the wbm+ and Bx7OE alleles on Mixograph and RVA properties and their extremely low frequencies in global wheat collections supported the idea of using these genes for bread-making quality improvement. The allele frequencies of wbm+ and Bx7OE were extremely low in historical Chinese and CIMMYT wheat germplasm, but were relatively higher in synthetic hexaploid wheats and their breeding derivatives. In both the Vavilov and Watkins global landrace collections, the frequency of wbm+ was 6.4 and 3.5%, and frequency of Bx7OE was 3.2% and 7.0%, respectively. The high-throughput marker resources and large-scale global germplasm screening provided further opportunities to exploit these genes in wheat breeding to enhance bread-making quality.

Thedryland root rot (foot/crown) caused by Fusarium spp. attacks cerealsespecially wheat and causes severe yield loss by reducing both grain quantityand quality. Among those Fusarium species attacking wheat crop is the Fusarium culmorum species which has beenreported as the main crown rot causal agent in Turkey. Unfortunately,up-to-date, there is only some wheat genotypes with partial resistant toFusarium spp. Therefore, this study was carried out to find new sources ofresistance in diverse wheat genotypes to limit the damage caused by Fusariumdisease. In this study, a total of 141genotypes and breeding lines were obtained from 19 different countries,provided via the International Winter Wheat Improvement Program (IWWIP) andscreened for their resistance reactions to a local isolate of Fusarium culmorum under three differentenvironmental conditions (growth room, greenhouse and field) in Turkey in 2012.The best performed genotypes in terms of resistant were then rescreened in 2013for data validation. Out of the 141 phenotyped wheat genotypes, 17 genotypes(12 %) ranked as moderately resistant (MR) at seedling and/or adult growthstage. The genotypes from Mexico seemed to have adult plant resistant ratherthan seedling resistance which was higher in the USA genotypes. Winter breadwheats PATWIN YR5 and TAST/SPRW//ZAR/5/YUANDONG3/4/PPB8-68/CHRC/3/PYN//TAM101/AMIGO which possess high level of resistance seem promising forbreeding for foot rot., Kuru alankök (kökboğazı/dip) çürüklükleri’ne neden olan Fusarium türleri tahıllaraözellikle buğdaya zarar vermekte, tane sayı ve kalitesini azaltarak önemliverim kaybına neden olmaktadır. Türkiye’de kök çürüklüğü hastalık etmeniFusarium türleri içinde buğday bitkisine zarar veren başlıca etmen olarak raporedilen tür Fusarium culmorum’dur.Maalesef, günümüze kadar Fusarium türlerine karşı sadece birkaç kısmi dayanıklıbuğday genotipi bulunmuştur. Bu nedenle, bu çalışma Fusarium hastalığının nedenolduğu zararı sınırlandırmak amacıyla çeşitli buğday genotiplerinde yenidayanıklılık kaynaklarının bulunması amacıyla yürütülmüştür. Çalışmada,Uluslararası Kışlık Buğday Geliştirme Programı (IWWIP) aracılığıyla 19 farklıÜlke’den toplam 141 ıslah materyali (hat ve çeşit) sağlanmıştır ve Türkiye’de 3farklı ortamda (büyütme odası,sera, tarla) yerel izolat Fusarium culmorum’a karşı dayanıklılıklarının belirlenmesi amacıyla2012 yılında test edilmiştir. Dayanıklılık bakımından en iyi performansıgösteren genotipler verilerin doğrulanması amacıyla 2013 yılında tekrar testedilmiştir. Fenotiplendirme yapılan 141 genotip içinden toplam materyalin %12’lik kısmını oluşturan 17 genotip fide ve/veya yetişkin dönemde orta dayanıklıolarak gruplandırılmıştır. Meksika kaynaklı genotipler, fide dayanıklılığı dahafazla gösteren Amerika kaynaklı genotiplerin aksine yetişkin dönemdayanıklılığı göstermiştir. Yüksek dayanıklılık gösteren kışlık buğdaylarPATWIN YR5 ve TAST/SPRW//ZAR/5/YUANDONG3/4/PPB8-68/CHRC/3/PYN//TAM101/AMIGO kök çürüklüğü’ ne karşı ıslahta ümitvarolarak görülmektedir.

Hexaploid synthetic wheat, derived from crosses between durum wheat and Aegilops tauschii, is widely accepted as an important source of useful traits for wheat breeding. During 2015 and 2016, three groups of synthetics were studied in Azerbaijan (3 sites) and Russia (1 site). Group 1 comprised CIMMYT primary synthetics derived from eastern European winter durum wheats crossed to Ae. tauschii accessions from the Caspian Sea basin. Group 2 included lines derived from CIMMYT synthetics × bread wheat crosses. Group 3 consisted of synthetics developed in Japan by crossing durum variety Langdon with a diverse collection of Ae. tauschii accessions. Varieties Bezostaya-1 and Seri were used as checks. Group 1 synthetics were better adapted and more productive than those in group 3, indicating that the durum parent plays an important role in the adaptation of synthetics. Compared to Bezostaya-1 synthetics produced fewer spikes per unit area, an important consideration for selecting bread wheat parents for maintenance of productivity. Synthetics had longer spikes but were not generally free-threshing. All synthetics and derivatives had 1000-kernel weights comparable to Bezostya-1 and significantly higher than Seri. All primary synthetics were resistant to leaf rust, several to stem rust, and few to stripe rust. Superior genotypes from all three groups that combine high expression of spike productivity traits and stress tolerance index were identified.

Development of winter wheat (Triticum aestivum) synthetics started at CIMMYT-Mexico in 2004, when winter durum wheat (Triticum turgidum) germplasm from Ukraine and Romania was crossed with Aegilops tauschii accessions from the Caspian Sea region. Chromosomes were doubled after pollination and embryo rescue, but chromosome number and cytological validation was not performed. F2 populations were grown in Mexico and were shipped to Turkey in 2008. During 2009–2015, these populations were subjected to rigorous pedigree selection under dry, cold, disease-affected environments of the Central Anatolian Plateau. The wide segregation and partial sterility observed in 2009 gradually decreased and, by 2016, most of the F8 single spike progenies demonstrated good fertility and agronomic performance. Since 2013, lines have been selected from synthetic populations and evaluated at multiple sites. Superior lines were characterized for resistance to leaf, stripe and stem rust, plant height, and reaction to common bunt and soil-borne pathogens. Thousand kernel weight of many lines exceeded 50 g, compared with the check varieties that barely reached 40 g. Threshability of synthetic lines varied from 0 to 95%, demonstrating genetic variation for this important domestication trait. Screening against Hessian fly, sunny pest and Russian wheat aphid identified several resistant genotypes. Both durum and Aegilops parents affected synthetic wheat traits. Several studies are underway to reveal the genetic diversity of synthetic lines and the basis of resistance to diseases and insects. This synthetic germplasm represents a new winter bread wheat parental pool. It is available upon request to interested breeding/research programmes.

Stripe rust, caused by Puccinia striiformis f.sp. tritici (Pst), is an important disease of winter wheat in Central Asia. Stripe rust races contain diverse virulence/avirulence patterns and change rapidly. Therefore the objectives of this research were to: (i) examine current pathotype variability of Pst races collected from Kazakhstan and Uzbekistan and (ii) evaluate stripe rust resistance in leading cultivars and advanced breeding lines targeted to those regions. Analyses of 152 Pst samples showed diverse virulence patterns with avirulence to Yr5, Yr10 and Yr15 being common. Most of identified races are among the rare. Analysis of a mixed Pst population showed 10 distinct pathotypes with frequencies ranged from 1.2 to 8.7%. The virulence patterns ranged from least ‘31–1.5’ and X-1.5 to highly virulent ‘86 + E16’. Seedling evaluation of 62 genotypes using the 10 pathotypes showed variations for resistance. Bunyodkor and Barhayot showed resistance to all pathotypes. Five Yr genes were postulated. Yr1 in KR12-5075, and Yr6 in KR11-03 and KR12-5003 were postulated. Yr5 combined with Yr10 and Yr15 genes were determined in Bunyodkor. The wheat genotypes also showed different levels of resistance in adult plant stage under field conditions. Twenty genotypes showed Pst populations in the two countries. Several resistant genotypes were identified, which should be further evaluated for release as new varieties or used in breeding programmes. Two resistant lines from this study were identified as new varieties in Georgia and Uzbekistan.

The wheat leaf rust fungus, Puccinia triticina, is found in the major wheat growing regions of the world and is a leading cause of yield loss in wheat. Populations of P. triticina are highly variable for virulence to resistance genes in wheat and adapt quickly to resistance genes in wheat cultivars. The objectives of this study were to determine the genetic relatedness of worldwide collections of P. triticina using restriction site associated genotyping by sequencing. A total of 558 isolates of P. triticina from wheat producing regions in North America, South America, Europe, the Middle East, Ethiopia, Russia, Pakistan, Central Asia, China, New Zealand, and South Africa were characterized at 6745 single nucleotide loci. Isolates were also tested for virulence to 20 near-isogenic lines that differ for leaf rust resistance genes. Populations that were geographically proximal were also more closely related for genotypes. In addition, groups of isolates within regions that varied for genotype were similar to groups from other regions, which indicated past and recent migration across regions. Isolates from tetraploid durum wheat in five different regions were highly related with distinct genotypes compared to isolates from hexaploid common wheat. Based on a molecular clock, isolates from durum wheat found only in Ethiopia were the first to diverge from a common ancestor form of P. triticina that is found on the wild wheat relative Aegilops speltoides, followed by the divergence of isolates found worldwide that are virulent to durum wheat, and then by isolates found on common wheat.

Genetic resistance against biotic stress is a major goal in many wheat breeding programs. However, modern wheat cultivars have a limited genetic variation for disease and pest resistance and there is always a possibility of the evolution of new diseases and pests to overcome previously identified resistance genes. A total of 125 synthetic hexaploid wheats (SHWs, 2n = 6x = 42, AABBDD, Triticum aestivum L.) were characterized for resistance to fungal pathogens that cause wheat rusts (leaf, Puccinia triticina, stem, P. graminis f.sp. tritici, and stripe, P. striiformis f.sp. tritici) and crown rot (Fusarium spp.), cereal cyst nematode (Heterodera spp.), and Hessian fly (Mayetiola destructor). A wide range of genetic variation was observed among SHWs for multiple (two to five) biotic stresses and 17 SHWs that were resistant to more than two stresses. The genomic regions and potential candidate genes conferring resistance to these biotic stresses were identified from a genome-wide association study (GWAS). This GWAS study identified 124 significant marker-trait associations (MTAs) for multiple biotic stresses and 33 of these were found within genes. Furthermore, 16 of the 33 MTAs present within genes had annotations suggesting their potential role in disease resistance. These results will be valuable for pyramiding novel genes/genomic regions conferring resistance to multiple biotic stresses from SHWs into elite bread wheat cultivars and providing further insights on a wide range of stress resistance in wheat.

Climate change is leading to increased occurrence of and yield losses to wheat diseases. Managing these diseases by introducing new, effective and diverse resistance genes into cultivars represents an important component of sustainable wheat production. In 2016 and 2017 a set of primary hexaploid synthetic wheat was studied under high disease pressure: powdery mildew, leaf and stem rust in Omsk; Septoria tritici and S. nodorum in Moscow. A total of 28 synthetics (19 CIMMYT synthetics and 9 Japanese synthetics) were selected as having combined resistance to at least two diseases in both years of testing. Two synthetics (entries 13 and 18) originating from crosses between winter durum wheat Ukrainka odesskaya-1530.94 and various Aegilopes taushii accessions, and four synthetics (entries 20, 21, 23 and 24) from cross between Canadian durum wheat Langdon and Ae. taushii were resistant to all four pathogens. Pathological and molecular markers evaluation of resistance suggests presence of new genes and diverse types of resistance. The novel genetic sources of disease resistance identified in this study can be successfully utilized in wheat breeding., Highlights • Primary synthetics demonstrated resistance to several important diseases. • Six entries were resistant to powdery mildew, leaf/stem rust, Septoria in 2016/17. • Resistance type varied from immunity to slow disease development. • The resistance is controlled by both known and possibly new genes. • The novel genetic sources of resistance are valuable for wheat breeding.

Wheat stripe rust (yellow rust [Yr]), caused by Puccinia striiformis f. sp. tritici, is an economically important disease of wheat worldwide. Virulence information on P. striiformis f. sp. tritici populations is important to implement effective disease control with resistant cultivars. In total, 235 P. striiformis f. sp. tritici isolates from Algeria, Australia, Canada, Chile, China, Hungary, Kenya, Nepal, Pakistan, Russia, Spain, Turkey, and Uzbekistan were tested on 20 single Yr-gene lines and the 20 wheat genotypes that are used to differentiate P. striiformis f. sp. tritici races in the United States. The 235 isolates were identified as 129 virulence patterns on the single-gene lines and 169 virulence patterns on the U.S. differentials. Virulences to YrA, Yr2, Yr6, Yr7, Yr8, Yr9, Yr17, Yr25, YrUkn, Yr28, Yr31, YrExp2, Lemhi (Yr21), Paha (YrPa1, YrPa2, YrPa3), Druchamp (Yr3a, YrD, YrDru), Produra (YrPr1, YrPr2), Stephens (Yr3a, YrS, YrSte), Lee (Yr7, Yr22, Yr23), Fielder (Yr6, Yr20), Tyee (YrTye), Tres (YrTr1, YrTr2), Express (YrExp1, YrExp2), Clement (Yr9, YrCle), and Compair (Yr8, Yr19) were detected in all countries. At least 80% of the isolates were virulent on YrA, Yr2, Yr6, Yr7, Yr8, Yr17, YrUkn, Yr31, YrExp2, Yr21, Stephens (Yr3a, YrS, YrSte), Lee (Yr7, Yr22, Yr23), and Fielder (Yr6, Yr20). Virulences to Yr1, Yr9, Yr25, Yr27, Yr28, Heines VII (Yr2, YrHVII), Paha (YrPa1, YrPa2, YrPa3), Druchamp (Yr3a, YrD, YrDru), Produra (YrPr1, YrPr2), Yamhill (Yr2, Yr4a, YrYam), Tyee (YrTye), Tres (YrTr1, YrTr2), Hyak (Yr17, YrTye), Express (YrExp1, YrExp2), Clement (Yr9, YrCle), and Compair (Yr8, Yr19) were moderately frequent (>20 to

Winter survival ability is important for autumn sown winter wheat (Triticum aestivum L.) in regions with cold winters. Wheat vernalization and photoperiod genes influence adaptation by regulating the timing of the transition from vegetative to reproductive growth to protect the floral meristem from cold temperatures. We evaluated winter injury of 287 genotypes from the Facultative and Winter Wheat Observation Nursery (FAWWON) in six field environments over 3 years (2014 to 2016) in Colorado. Entries were genotyped using single-nucleotide polymorphisms (SNPs) obtained by genotyping by sequencing (GBS) and at known vernalization (Vrn-A1, Vrn-B1, and Vrn-D1) and photoperiod (Ppd-B1 and Ppd-D1) loci using Kompetitive Allele Specific PCR (KASP) assays. Winter injury was observed and visually scored in five of the six environments. Mean GS prediction accuracies across the five environments, obtained through ridge regression best linear unbiased prediction (RR-BLUP) using 23,269 SNPs alone as random effects, ranged from 0.26 ± 0.01 to 0.74 ± 0.00. Incorporation of alleles at Vrn-A1, Vrn-B1, and Vrn-D1 loci as fixed effects in the GS models together with GBS markers as random effects provided the highest prediction accuracy with mean GS accuracies ranging from 0.34 ± 0.01 to 0.78 ± 0.00 across the five environments. Genomic selection models incorporating photoperiod alleles as fixed effects rarely improved GS prediction accuracy of winter injury. Genomic selection models that incorporate both major and minor genetic factors that influence low-temperature tolerance improved the model predictions for identifying genotypes that are best adapted to regions where cold winter temperatures are an important production constraint.