Wheat Varieties Research Articles

Relative Benefits of Aqueous Extract of Sorghum Residues with Herbicide on Weed Control and Yield of Wheat Varieties

Reducing herbicide use in agriculture is key for sustainability, addressing costs, environmental issues, and resistance problems. Using non-chemical methods like allelopathy in weed management offers a viable alternative. In this phenomenon, a field study was carried out at the Agronomy Field Laboratory (AFL) of Bangladesh Agricultural University (BAU), Mymensingh, from November 2021 to March 2022, to assess the phytotoxic effects of herbicides combined with aqueous extract of sorghum (AES) on weed management and yield of wheat. This study used three wheat varieties viz. BARI Gom (wheat)-32, BARI Gom-33, and BWMRI Gom-1 and six treatment levels such as, no weeding, recommended dose of herbicide (RDH), 90% RDH + AES (1:20 w/v), 80% RDH + AES (1:20), 70% RDH + AES (1:20), and 60% RDH + AES (1:20). The experiment followed a randomized complete block design (RCBD) with three replications. The RDH with AES and wheat variety significantly influenced weed population (WP) and dry weight (DW) of weeds. BARI Gom-32 produced the highest grain yield (GY) and other yield-contributing characteristics. The best results, including the highest numbers of tillers (NET) hill-1 (6.47), spike length (SL) (15.10 cm), number of spikelet spike-1 (NSS) (19.38), 1000-grain weight (TGW) (57.67g), GY (5.10 t ha-1), and straw yield (SY) (7.07 t ha-1) and harvest index (HI) (41.95%) were observed in plots treated with the RDH and the BARI Gom-32 variety, followed closely by those receiving 90% RDH + AES (1:20). The results demonstrate that varying concentrations of AES crop residue can effectively suppress weed growth and enhance wheat yield, suggesting that sorghum residues might be utilized to manage weeds effectively and sustainably while boosting wheat production. The study supports the potential of AES crop residue as an effective means to control weeds and significantly improve wheat yields. J Bangladesh Agril Univ 22(3): 326-334, 2024

Influence of phosphorous fertilizer on mineral nutrition and yield attributes of wheat: Acquisition with PSTOL1 gene for arid environment

To boost agricultural yields, understanding mineral nutrition’s reliance on fertilizers is crucial, underscoring the need to evaluate nutrient-use efficiency for optimal fertilization. In this regard, a field study was conducted to elaborate the role of phosphorus fertilizer in enhancing growth, yield and marginal rate of return in four wheat varieties; two Zn-biofortified (Zincol-2016 and Akbar-2019) and two standard types (Anaj-2017 and FSD-2008). The study revealed that application of phosphorus significantly enhanced the uptake of nitrogen (N), phosphorous (P) and potassium (K) contents in straw (13 %, 59 % and 79 %) and grains (63 %, 92 % and 28 %) respectively. Similarly, the contents of Zinc (Zn) and iron (Fe) were reduced in straw (23 % and 19 %) and grains (19 % and 18 %) respectively after application of 80 and 120 kg P2O5, however at 40 kg P2O5 the contents of Zn and Fe were slightly enhanced. The grain yield (21 %) and harvest index (11 %) was maximum at 80 kg P2O5 as compared to 40 and 120 kg P2O5. The Marginal rate of return over investment (MRR) in P2O5 was maximum (241 %) in Akbar-2019 when P-fertilizer was applied at the rate of 80 kg P2O5 per ha−1. Regression analysis showed a positive correlation between grain yield and its determinants. Biofortified wheat varieties responded better to 80 kg P2O5, outperforming standard varieties in yield. Additionally, our findings demonstrate a significant upregulation of PSTOL1 gene expression at 80 kg P2O5 level. Concludingly the application of P-fertilizer at the rate of 80 kg P2O5 per ha−1 enhanced growth, yield and rate of return of testing wheat varieties especially the biofortified ones; Zincol-2016 and Akbar-2019.

Identification of high-yielding and stable cultivars of wheat under different sowing dates: Comparison of AMMI and GGE-biplot analyses

Evaluating the adaptability and yield stability of wheat varieties across different sowing dates is crucial for the success of breeding programs. In this study, we used Additive Main Effects and Multiplicative Interactions (AMMI) and Genotype × Genotype–Environment (GGE) biplot analyses to evaluate the performance of 13 wheat varieties across eight sowing dates. The main objective was to compare varieties and sowing dates to identify the most stable varieties for cultivation. Both AMMI and GGE biplot analyses showed significant effects of genotype, environment and genotype-environment (GE) interaction on grain yield. The interaction patterns identified by AMMI and GGE-biplots categorized Mihan, Oroom and Pishgam as the most stable, high yielding and early maturing wheat varieties. Furthermore, while the GGE biplot method proved to be more efficient than the AMMI model for stability analysis, our results indicate considerable overlap between the results of these two approaches. These results provide a valuable basis for optimizing genetic improvement strategies in wheat breeding programs.

Effects of Water Stress on Water Consumption, Water Use Efficiency of Different Wheat Varieties

Effects of Water Stress on Water Consumption, Water Use Efficiency of Different Wheat Varieties

Evaluation of Bread Wheat (Tritium aestivum L.) Genotype in Multi-environment Trials Using Enhanced Statistical Models

In varietal selection field trials, spatial variation and genotype by environment (GxE) interaction are frequent and present a major challenge to plant breeders comparing the genetic potential of several cultivars. To consistently select superior cultivars that increase agricultural production, bread wheat breeding studies must be evaluated using efficient statistical techniques. By modeling the interactions of geographical field trends and genotypes by environment interaction, this work aimed to forecast the genetic potential of bread wheat varieties across settings and improve selection tactics. The dataset utilized in this investigation consisted of sixteen multi-environment trials (MET) that were carried out using a randomized complete block design (RCBD), with two replications arranged in plot arrays of rows and columns. The findings showed that the factor analytical and spatial models were effective ways to analyze the data for this study under the linear mixed model. By ranking average Best Linear Unbiased Predictions (BLUPs) within clusters, the 16 bread wheat environments were grouped into three mega environments (C1, C2, and C3) based on yield. This served as a selection indicator. Ranking average BLUPs helped in the selection of superior and stable genotypes. The first cluster (C1)'s mean BLUP values were used to score the genotypes' performance; C2 and C3 were excluded because of their limited genetic variety and low genetic connection with the other trials. The genotypes with the highest potential based on this cluster were EBW192346 and EBW192347, chosen for a subsequent verification study to release a variety. The estimates for variance component parameters ranged from 0.013 to 3.024 for genetic variance and from 0.072 to 0.37 for error variance. Hence, scaling up the use of this efficient analysis method will improve the selection of superior bread wheat varieties.

The transcription factor TaNF-YB4 overexpression in wheat increases plant vigor and yield

Ensuring food security is a priority in developing countries. This study aimed to improve wheat yield by overexpressing the TaNF-YB4 transcription factor, which is involved in carbon assimilation and stress tolerance. An expression cassette for TaNF-YB4 was developed in a modified wheat transformation vector (pSB219) and examined through transient expression in Nicotiana tabacum, followed by Agrobacterium-mediated transformation of wheat variety FSD-2008. T0 transgenic plants were propagated to obtain T3 generation PCR-positive plants. Transgene expression was assessed in PCR-verified T2 plants using RT-PCR and qRT-PCR at six weeks post-germination. qRT-PCR analysis using the ΔΔCT method indicated higher TaNF-YB4 expression in transgenic lines than in the wild-type control plants. Improved agronomic and phenotypic traits were observed with a 6-36% increase in 1000-grain weight in the selected transgenic lines. Root architecture assessments demonstrated enhanced root length, surface area, and projected area in transgenic lines compared with wild-type plants. Additionally, notable variances in total chlorophyll, protein, and sugar content levels were observed between the transgenic lines and control plants, demonstrating statistical significance with a p-value ≤ 0.05. This study indicates that low-level constitutive expression of TaNF-YB4 can enhance wheat yield, presenting a viable strategy for improving wheat productivity.

Nuclear integration of MYB36 and APX-1 genes impart heat tolerance in wheat.

Elevated temperatures during grain filling stage, exceeding the optimal range by 3-4°C, not only results in a substantial yield reduction in wheat by 10-50% but activates disease and insect infestation. In this research, we introduced heat-tolerant MYB36 and APX-1 gene cassettes into wheat, employing an efficient Agrobacterium mediated transformation protocol, demonstrating higher transformation efficiency. The study encompassed the assembly of MYB36 and APX-1 gene cassettes, and confirmation of gene products in Agrobacterium, followed by the transformation of the MYB36 and APX-1 genes into wheat explants. We were able to select transgenic plant with various combinations. The transgenic plants with APX-1 gene alone produced medium sized grain and spike whereas with both APX-1 and MYB36 genes expressed individually under SPS and rd29a promoter respectively showed good tolerance to heat at 32oC at grain filling/milking stage and produced relatively bold grains. While non-transgenic plants grains were wrinkled with thin spike showing susceptibility to heat. This research contributes to the broader scientific understanding of plant stress responses and the combined effectiveness of MYB36 and APX-1 genes in crop improvement without disturbing normal nutritional values. The gene integration can serve as a valuable tool in breeding programs aimed at developing heat-tolerant wheat varieties. These findings also advance our comprehension of the functions of heat-induced genes and lay the foundation for selecting optimal candidates for in-depth functional studies of heat-responsive MYB36 and APX-1 genes in wheat.

Genetic dissection and genomic prediction of drought indices in bread wheat (Triticum aestivum L.) genotypes.

Drought constitutes the main obstacle to agricultural productivity in the Central and West Asia and North Africa (CWANA) region, notably leading to substantial reductions in wheat yields due to terminal water stress. The adoption of drought-resistant wheat varieties appears to be a vital strategy to maintain wheat production in the face of climatic challenges. In this context, a study was conducted utilizing a set of 198 elite bread wheat genotypes developed at the International Center for Agricultural Research in the Dry Areas (ICARDA). This set of elite genotypes was evaluated at the Sidi Al-Aidi station in Morocco over two years (2021-2022), under rain-fed and irrigated conditions. Phenotypic assessments for grain yield and drought indices were performed, alongside genotyping the population using 15k SNP markers. These preparatory steps facilitated a genome-wide association study (GWAS) and genomic prediction, leveraging the Mixed Linear Model (MLM) to pinpoint marker-trait associations (MTAs) and candidate genes pertinent to grain yield and drought indices. The results manifested substantial variations in both grain yield and drought indices among the genotypes tested. Grain yield performance ranged from 0.34 to 2.57 t/ha under rain-fed conditions and 1.12 to 4.57 t/ha under irrigated scenarios. The comprehensive analysis identified 39 significant MTAs (p < 0.001) and 14 putative genes associated with drought indices and grain yield. Noteworthy is the marker “wsnp_Ex_c12127_19394952” on chromosome 5B, which displayed a significant correlation with grain yield in rain-fed environments. Furthermore, the most prominent marker linked to tolerance index (TOL) was “BobWhite_c42349_99”, situated on chromosome 5A and associated with the TraesCS5A02G498000 gene. This gene plays a critical role, encoding for catalase protein crucial for response to hydrogen peroxide. These markers could be used for marker-assisted selection in wheat breeding programs targeting drought tolerance.

Calibration and Validation of Reproductive Stages of Wheat Varieties with CERES-Model under Sowing Environments in Irrigated Conditions of Jammu, India

Calibration and Validation of Reproductive Stages of Wheat Varieties with CERES-Model under Sowing Environments in Irrigated Conditions of Jammu, India

ANCIENT CEREAL CULTURE FOR THE MODERN GROAT INDUSTRY

At the origin of wheat-spelt breeding in Ukraine is the outstanding scientific breeder Fedir Pariy. As of today, seven varieties of wheat-spelt have been entered into the Register of plant varieties suitable for distribution in the territory of Ukraine. The first variety of spelt wheat Triticum spelta L. "Zoria Ukrainy" was entered into the register in 2011, and from that began the active study of this type of hulled wheat not only by breeders, but also by technologists, the goal of which was the introduction of hulled wheat in the domestic grain processing industry. Two years later, in 2013, the second variety of domestic spelled wheat "Yevropa" was entered into the register, the work on the selection of which was also headed by Fedir Pariy. The following varieties of spelt wheat were entered into the Register relatively recently during 2017-2021: Attergauer Dinkel (2016), Evrika (2017), Mv Martongold (2018), Vyshyvanka bilotserkivska (2018), Bilberi (2021). Considering wheat-spelt grain as a potential raw material for cereal production, it can be noted that thanks to the excellent chemical composition of the grain and its affinity with the grain of traditional wheat, it can be concluded that it can be processed at domestic grain factories of different productivity, using at the same time as the traditional available on technological equipment at the enterprise, and when building new lines and factories, use more modern solutions offered by world leaders in the production of technological equipment, such as the Buhler company. At the same time, it is possible to produce both a higher-quality product, traditional for the Ukrainian consumer, such as "Artek" and "Poltavska"groats, and to focus on the production of a new range of wheat products - the production of whole groats and flaked kernels, which in turn, with rational construction and the use of more efficient technological equipment, will give be able to produce functional and dietary food products. In addition, due to such products, the export potential of the grain processing industry can be increased, especially taking into account the small amount of spelt wheat cultivation in the countries of the European Union, with the constant increase in demand for environmentally friendly and high-quality products that are available in these countries, with the right approach, can make Ukraine an exporter of wheat-spelt processing products to EU countries and beyond.

Impact of Planting Time on the Performance of Different Wheat Varieties: A Review

Wheat (Triticum aestivum L.) is among the most widely cultivated cereal crops globally. Wheat belongs to family Poaceae and genus Triticum and its center of origin is South Western Asia. Following China, India is the second-largest wheat producer in the world. Among different species of wheat crop, Triticum aestivum is the most prime because of its higher calorific values as well as a good addition for nutritional requirement of human body due to appearance of 9-10 % protein and 60-80 % carbohydrates. Choosing the appropriate sowing time and selecting suitable cultivars are crucial for achieving higher wheat yields. Early sowing with the optimal plant population promotes better growth and nutrient uptake, leading to increased crop production. Delayed sowing reduces the growth, yield, and quality of wheat grain, while early sowing leads to greater yields thanks to a longer grain development phase. Additionally, cultivar selection played a crucial role in determining wheat performance. Some cultivars exhibited greater adaptability to varying sowing dates, maintaining higher yields and better stress tolerance. Proper selection of cultivars is obtained to maximum yield due to variation among the weather conditions and genetic diversity. Optimum sowing dates give suitable temperature to obtain maximum productivity and cultivars selection also play prime role in obtaining maximum wheat production. Improper selection of cultivars produces lower grain yield.

Identification of Genomic Regions Conferring Enhanced Zn and Fe Concentration in Wheat Varieties and Introgression Lines Derived from Wild Relatives.

Wild and cultivated relatives of wheat are an important source of genetic factors for improving the mineral composition of wheat. In this work, a wheat panel consisting of modern bread wheat varieties, landraces, and introgression lines with genetic material of the wheat species Triticum timopheevii, T. durum, T. dicoccum, and T. dicoccoides and the synthetic line T. kiharae was used to identify loci associated with the grain zinc (GZnC) and iron (GFeC) content. Using a BLINK model, we identified 31 and 73 marker-trait associations (MTAs) for GZnC and GFeC, respectively, of which 19 were novel. Twelve MTAs distributed on chromosomes 1B, 2A, 2B, 5A, and 5B were significantly associated with GZnC, five MTAs on 2A, 2B, and 5D chromosomes were significantly associated with GFeC, and two SNPs located on 2A and 2B were related to the grain concentration of both trace elements. Meanwhile, most of these MTAs were inherited from At and G genomes of T. timopheevii and T. kiharae and positively affected GZnC and GFeC. Eight genes related to iron or zinc transporters, representing diverse gene families, were proposed as the best candidates. Our findings provide an understanding of the genetic basis of grain Zn and Fe accumulation in species of the Timopheevi group and could help in selecting new genotypes containing valuable loci.

ASSESSMENT OF WHEAT GENOTYPES FOR THEIR LOW NITROGEN USE EFFICIENCY UNDER SEMI-ARID CONDITIONS OF PUNJAB, PAKISTAN

Nitrogen is one of the most important and critical macronutrients needed by plants for their optimal growth and development. The current experimental study was designed to examine the response of wheat variety Akbar-2019 under different nitrogen levels keeping the levels of phosphorus and potassium constant. The study was conducted in Chak No. 169/7.R Fort Abbas, District Bahawalnagar under the supervision of the Department of Soil Fertility (Field) during the crop year 2022-23. The experimental material was comprised of a wheat variety Akbar-2019 and five different treatments of nitrogen consisted of (i) N = 160 kg ha-1 (ii) N = 145 kg ha-1 (iii) N = 131 kg ha-1 (iv) N = 117 kg ha-1 and (v) N = 103 kg ha-1. The experiment was laid out under a randomized complete block design with three replications and 170 m² net plot size par treatment per replication. The results revealed the presence of highly significant variations among nitrogen treatments in wheat variety based on the agronomic and morpho-physiological parameters including flag leaf area, thousand-grain weight, grains per spike, relative water contents, stomatal conductance, net photosynthetic rate, biological yield and gain yield. Furthermore, the results also unveiled that treatments with higher nitrogen dosage produce better results for almost all the study parameters including grain yield. These results were also confirmed through correlation coefficient analysis and bar graph graphical representation based on mean data, where correlation coefficient analysis showed a strong positive correlation of grain yield with studied plant traits except biological yield for which the correlation was positive but non-significant. The results suggest that nitrogen in higher amounts up to a certain level is necessary for obtaining maximum output from wheat crops under semi-arid conditions.

Response of the flag leaf for Moroccan bread wheat varieties in the field, highlighting its biochemical composition in its resistance mechanism against yellow rust

This investigation aimed to assess the responsiveness of fourteen Moroccan bread wheat varieties to yellow rust induced by Puccinia striiformis tritici (Pst) in comparison with a susceptible variety ‘Amal’ through natural inoculation in the field, employing a Randomized Complete Block Design (RCBD). A comprehensive evaluation, encompassing 20 variables related to epidemiological, phenological, morphological, and physicochemical parameters, was conducted. In elucidating the role of the leaf in wheat resistance to stripe rust, the mineral and organic composition was scrutinized using sophisticated molecular detection techniques—Fourier Transform Infrared Spectroscopy (FTIR) and Atomic Absorption Spectroscopy (AAS). These two methodologies, recognized for their efficacy, facilitated the measurement of varying concentrations of lipids and carboxylic esters in the epicuticular wax on the adaxial flag leaf. Additionally, the quantity of essential minerals was determined. The outcomes revealed distinct responses among bread wheat varieties to stripe rust, with ‘Faiza’, ‘Bandera’, and ‘Resulton’ demonstrating heightened resistance, manifesting severity values below 15%. Conversely, ‘Amal’ exhibited the lowest level of resistance. Furthermore, lipid concentration reached its pinnacle in ‘Faiza’, ‘Bandera’ and ‘Resulton’ while ‘Amal’ displayed the lowest lipid levels. Severity exhibited a very weak correlation with Zn, weak correlations with Cu, and moderate correlations with Ca and K (p&lt;0.05). This study provides valuable insights guiding future research endeavours aimed at enhancing the genetic traits of these elite cultivars for integration into Morocco’s cereals program.

ОРГАНИЗАЦИЯ СЕМЕНОВОДСТВА СЕЛЬСКОХОЗЯЙСТВЕННЫХ КУЛЬТУР НА ОРОШЕНИИ И ТЕХНИКА ПОЛИВА (НА ПРИМЕРЕ ЯРОВОЙ ПШЕНИЦЫ)

his paper presents a brief summary of research work carried out in 2012-2022. on the irrigated fields of the peasant farm of IP "Vafin R.K." Laishevsky and LLC AF "Kyrlay" Arsky municipal districts of the Republic of Tatarstan on the selection of short-stemmed, resistant to lodging, diseases and pests, highly responsive to additional moisture of such spring wheat varieties as Zlata, Kazanskaya Yubileynaya, Omskaya 33 and varietal technology for their cultivation. It was found that when placing spring wheat on a layer of irrigated perennial grasses and after spring rapeseed, optimizing nutrition backgrounds, using modern biologics and seed protectants, high-quality basic and pre-sowing soil preparation, compliance with sowing methods and timing, intensification of crop care techniques, including digital technologies for determining the timing and quality of irrigation, provides more than 6.0 tons/ ha of grain with a yield of commercial seeds at the level of 65-76%, with a mass of 1000 seeds of 40 or more g corresponding to the second class of quality in terms of gluten, protein, vitreous and grain nature.

Analysis of wheat traits that determine female farmers’ preferences for wheat varieties: Gender insight from southern tigray, ethiopia

BackgroundWheat productivity has been constrained by changing agroecological and socio-economic conditions, coupled with a lower uptake of new farm technologies. Gender difference is one major social category that needs systematic estimation to distinguish the adoption of technology and the preference between male and female farmers. Hence, this study analyzes wheat traits that determine female farmers’ preferences for wheat varieties in southern Tigray, Ethiopia.MethodsThe primary data was collected by using semi-structured interviews, focus group discussions, and key informant interviews from 169 female farmers who were selected by using a two-stage sampling procedure. This study used descriptive statistics and a multinomial logit model to estimate the wheat traits that determine the wheat variety preference of female farmers.ResultThe result obtained from descriptive statistics shows the existence of heterogeneity in trait preference of female farmers among bread wheat, durum wheat, and local wheat variety types. The result indicates that risk-averting traits were the most frequently selected traits for both wheat types. Furthermore, the result of multinomial logit model indicates that wheat variety traits such as yield difference, marketability, resistance to drought, and resistance to frost and disease significantly influenced female farmers’ choice of wheat variety to grow.ConclusionThis study aims to fill the current knowledge gaps and tackle the significant issues faced by wheat-growing female farmers by examining the wheat traits that influence the wheat variety choice of these farmers. The finding scrutinized that even though the female farmers’ choices of wheat variety traits were heterogeneous, the majority of their decisions on the choice of wheat variety were primarily guided by risk-averting and yield traits. This evidence provides significant insight for developing gender-sensitive variety traits in crop breeding programs. Moreover, the findings significantly help policymakers, input suppliers, breeding programs, and extension workers to become more gender-responsive, to increase the productivity of wheat-growing female farmers.

On the Anniversary of the Academician of the National Academy of Sciences of Belarus Stanislav Ivanovich Grib

Stanislav Ivanovich Grib, Doctor of Agricultural Sciences, Professor, an Honored Scientist of the Republic of Belarus, a Laureate of the State Prize of the Republic of Belarus, an Academician of the National Academy of Sciences (NAS) of Belarus, a Foreign Member of the Russian Academy of Sciences and the National Academy of Agrarian Sciences of Ukraine, a talented Belarusian scientist in the field of plant breeding, known in the country and abroad, the leader of the Belarusian scientific school in the area of breeding and seed production, an experienced organizer of agricultural science, turned 80 years old on August 6, 2024. He was the first in Belarus to scientifically substantiate and implement in practice a new scientific direction, that is, breeding of intensive varieties of grain crops with a yield of 10-12 t/ha of grain; developed methods for broadening genetic diversity and identifying genotypes that combine high productivity and good product quality with tolerance to biotic and abiotic environmental factors; substantiated the parameters of the model of intensive varieties; created and introduced into production systems of highly productive, resource-saving varieties of barley, triticale, and spring wheat. The results of his research have been published in more than 700 scientific works, including 12 monographs, books and textbooks. Stanislav Ivanovich is the author of eight inventions and 89 varieties of agricultural plants. Academician S.I. Grib, the leader of the scientific school of plant breeding in Belarus, trained four doctors and twelve candidates of science. S.I. Grib's achievements have been recognized abroad. He was elected a foreign member of the Russian Academy of Sciences and the National Academy of Agrarian Sciences of Ukraine, an Honorary Professor of the Siberian Branch of the Russian Academy of Sciences, a member of the European Association of Plant Breeders (EUCARPIA), and an Honorary Doctor of the Belarusian Agricultural Academy (BSAA). Stanislav Ivanovich was awarded the Order of the Badge of Honor, a diploma of the Supreme Council of the BSSR, medals and diplomas of the Exhibition of Economic Achievements, honorary diplomas of the National Academy of Sciences of Belarus, the Ministry of Agriculture and Food of the Republic of Belarus, and the Scientific and Practical Center of the National Academy of Sciences of Belarus for Agriculture.

Evaluation of grain yields of selected bread wheat (triticum aestivum l.) Varieties in changing climatic conditions using different analytical models

In the present study were determined the variety or varieties with high grain yield and stability despite changing climatic conditions, and also to include these varieties as genetic material in parent lists in breeding programs. The additive main effect and multiplicative interaction (AMMI) analysis results the effects of cultivars (C), environments (E) and cultivar x environment interaction (CEI) were found to be important over grain yield at p≤0.01 level. Also, showed that grain yield performance of bread wheats were greatly affected firstly by the environment (70.42%), secondly from the interaction (7.29%), the least by variety (6.79%). The polygon graph obtained by genotype, genotype x environment (GGE) biplot analysis showed that two separate mega environments were formed, Nurkent variety was the best for first mega-environment, while Pehlivan variety for the second mega environment. GGE biplot determined that the ideal environment for bread wheat was environment 9 (E9) and the ideal genotype was Nurkent. Due to the visual presentation of AMMI and GGE biplot graphs, analysis results showed that these two models can be used to visually identify the best genotypes. Bangladesh J. Bot. 53(3): 545-554, 2024 (September)

Identification and fine mapping of a QTL-rich region for yield-and quality-related traits on chromosome 4BS in common wheat (Triticum aestivum L.).

Yield and quality are important for plant breeding. To better understand the genetic basis underlying yield- and quality-related traits in wheat (Triticum aestivum L.), we conducted the quantitative trait locus (QTL) analysis using recombinant inbred lines (RILs) and a high-density genetic linkage map with a 90K array. In this study, a total of 117 QTLs were detected for spike number per area (SNPA), thousand grain weight (TGW), grain number per spike (GNS), plant height (PH), spike length (SL), total spikelet number (TSN), spikelet density (SD), grain protein content (GPC), and grain starch content (GSC). Among these QTLs, 30 environmentally stable QTLs for yield- and quality-related traits were detected. Notably, five QTL-rich regions (Qrr) for yield-and/or quality-related traits were identified, including the QTL-rich region on chromosome 4BS (QQrr.cau-4B) for eight traits (SNPA, GNS, PH, SL, TSN, SD, GPC, and GSC). The stable QTL-rich region QQrr.cau-4B was delimited into a physical interval of approximately 2.47Mb. Based on the annotation information of the Chinese spring wheat genome v1.0 and parental re-sequencing results, the interval included twelve genes with sequence variations. Taken together, these results contribute to further understanding of the genetic basis of SNPA, GNS, PH, SL, TSN, SD, GPC, and GSC, and fine mapping of QQrr.cau-4B will be beneficial for gene cloning and marker-assisted selection in the genetic improvement of wheat varieties.

ZymoSoups: A high-throughput forward genetics method for rapid identification of virulence genes in Zymoseptoria tritici.

Septoria tritici blotch is caused by the fungus Zymoseptoria tritici and poses a major threat to wheat productivity. There are over twenty mapped loci in wheat that confer strong (gene-for-gene) resistance against this pathogen, however the corresponding genes in Z. tritici that confer virulence against distinct R genes remain largely unknown. In this study, we developed a rapid forward genetics methodology to identify genes that enable Z. tritici to gain virulence on previously resistant wheat varieties. We used the known gene-for-gene interaction between Stb6 and AvrStb6 as a proof-of-concept that this method could quickly recover single candidate virulence genes. We subjected the avirulent Z. tritici strain IPO323, which carries the recognized AvrStb6 allele, to UV mutagenesis and generated a library of over 66,000 mutants. We screened these mutants on leaves of the resistant wheat variety Cadenza, in mixtures (soups) ranging from 100-500 mutants per soup. We identified five soups with a gain-of-virulence (GoV) phenotype relative to the IPO323 parental strain and re-sequenced 18 individual isolates, including four control isolates and two mutants lacking virulence, when screened individually. Of the 12 confirmed GoV mutants, one had a single nucleotide polymorphism (SNP) in the AvrStb6 coding region. The other 11 GoV mutants exhibited large (~70Kb) deletions at the end of chromosome 5, including the AvrStb6 locus. Our findings demonstrate the efficiency of this forward genetic approach in elucidating the genetic basis of qualitative resistance to Z. tritici and the potential to rapidly identify other, currently unknown, Avr genes in this pathogen.