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Assessment of genetic diversity and population structure of almond germplasm in Van Province, Türkiye, using iPBS-retrotransposon-based markersOriginal Paper

Berna Sarman, Metin Koçak

Czech J. Genet. Plant Breed., 2026, 62(3):135-145 | DOI: 10.17221/12/2026-CJGPB

The genetic characterisation of naturally occurring almond genotypes can guide the selection of genetic resources to be used in the breeding programme. Therefore, this study aims to assess the genetic diversity and population structure of almond germplasm comprising 50 accessions naturally occurring in Van, Türkiye, along with two commercial varieties (Pabuç and Dokuzoğuz). Thirteen inter-primer binding site (iPBS) retrotransposon markers generated a total of 102 bands, of which 95 were polymorphic. The average polymorphic band number per marker was 7.3, with a range of 5 to 13. A formula yielding a maximum of 0.5 resulted in polymorphic information content (PIC) values between 0.27 and 0.43, with a mean value of 0.36. Unweighted pair group method algorithm (UPGMA), principal coordinate analysis (PCoA), and STRUCTURE analysis, based on Bayesian clustering analysis, yielded consistent results, indicating that local populations (Akdamar and Çarpanak) were distinctly grouped, while commercial accessions were clustered with Çarpanak accessions. The diversity metrics and classification analysis utilising 13 iPBS-retrotransposon markers demonstrated that the iPBS-retrotransposon marker system possesses significant promise for evaluating the genetic variety and population structure of almonds.

Association ana­lysis of the molecular characteristics and floral traits of Iris × germanicaOriginal Paper

Feng Tian, Ya Tian, Fang Yu, Jinsen Qian, Feijian Wang, Xue Li, Tongyin Li, Xiaofei Zhang, Dazhuang Huang, Xiaojie Zhao

Czech J. Genet. Plant Breed., 2025, 61(2):55-66 | DOI: 10.17221/93/2024-CJGPB

Iris × germanica L. (bearded iris) is a popular ornamental plant with numerous commercially important cultivars; however, little is known about the genetic diversity and population structure of the species, as limited DNA markers have been explored. In this study, 34 722 expressed sequence tag (EST)-simple sequence repeat (SSR) loci were identified from RNA sequencing data. The most abundant SSR motifs belonged to the tri-nucleotide type, of which the most common were AGG/CCT followed by AAG/CTT. Overall, 50 primer pairs derived from these EST-SSRs were randomly selected and synthesized, and 22 primer pairs with good polymorphism effects were used for the following experiment. Correlation analysis of nine floral traits showed that most floral traits had significant correlations with each other. Association analysis between SSR molecular markers and nine floral traits showed that 11 EST-SSR markers were associated with 3–6 floral traits. The cluster tree constructed by using the unweighted pair group method demonstrated that the cultivars that had the same parents or similar colour were clustered together. The genotypic relations of most cultivars were consistent with their pedigree-based relationships. The EST-SSR loci identified in this study will facilitate the exploitation of genetic resources and molecular breeding of I. × germanica.

Unravelling population structure and marker trait association using SSR markers among the identified drought tolerant rice landraces (Oryza sativa L.)Original Paper

Shanmugam Manju Devi, John Amalraj Joel, Muthurajan Raveendran, Ramamoorthy Pushpam, Sengalan Muthuramu, Raman Pushpa, N. Sritharan, Periyasamy Prasanna, Ramalingam Suresh

Czech J. Genet. Plant Breed., 2025, 61(1):1-22 | DOI: 10.17221/12/2024-CJGPB

With climate change, plants face numerous stresses, notably drought for rice cultivation. Improving rice drought tolerance is vital for sustainable production in water-scarce regions. Identification of drought tolerant genotypes at the seedling stage of the crop contributes to build a climate resilient genotype during the period of water scarcity and under challenging environmental conditions. Hence, polyethylene glycol-6000 (PEG-6000) induced drought conditions could be used for testing the drought tolerance in rice at an earlier stage of the crop. Optimization of PEG-6000 concentration for screening index at -6 bar was done using three drought-tolerant and two drought-susceptible check varieties based on probit analysis. Subsequently, 100 rice landraces underwent PEG-6000 induced drought screening at –6 bar and a total of 32 genotypes were selected as tolerant. After 14 days of treatment, the nine observations viz. germination %, root length (cm), shoot length (cm), number of secondary roots, fresh weight (g), dry weight (g), shoot/root ratio, root/shoot ratio and vigour index were recorded. Variance analysis, revealing significant genetic variation among genotypes for all studied traits, indicating genetic variability. Post hoc analysis confirmed notable variation among treatments. Principal component analysis revealed three components, with the first three accounting for 88.89% of total variability. With respect to the biplot, the ten genotypes viz., IRGC109, IRGC403, IRGC448, IRGC461, IRGC466, IRGC486, IRGC508, IRGC518, IRGC527 and IRGC535 are the seedling stage drought tolerant genotypes based on shoot length, number of secondary roots and vigour index. Population structure classified the accessions into two subpopulations, reflecting diversity. The allele frequency divergence is 0.095 which is a measure of fixation index revealing that the moderate divergence is not extremely pronounced. Genetic diversity, assessed through 26 SSR markers selected from drought tolerant QTLs and markers related to vigour index, exhibited 100% polymorphism with 115 alleles and an average PIC value of 0.61 per primer. Shannon index varied between 0.34 (RM212) and 1.96 (RM252), averaging 1.18. Six SSR markers viz., RM246, RM302, RM252, RM219, RM251, and RM486 were associated with the six key traits viz., shoot length, root length, number of secondary roots, dry weight, shoot/root ratio, and root/shoot ratio respectively offering valuable resources for selecting drought-tolerant accessions as it provides the first step in the selection of genotypes based on the key traits.

Seasonal and microclimate-responsive expression of VRN-A1 and VRN-B1 in wheat under field conditionsOriginal Paper

Nicole Frantová, Ilja Tom Prá¹il, Ludmila Holková

Czech J. Genet. Plant Breed., 2026, 62(2):53-63 | DOI: 10.17221/76/2025-CJGPB

The need of vernalisation, controlled by the gene VRN-1, impacts wheat adaptation and yield stability, yet field evidence on the plasticity of VRN-1 homoeologs expression is limited. We quantified VRN-1 homoeolog dynamics across two sites and two seasons in seven cultivars, by sampling their apex and leaf. VRN-A1 varied with genotype (P < 0.001***), tissue (apex > leaf; P < 0.001***), apex development (P < 0.001***), day length (P < 0.001***), and to a lesser extent, on short-term freezing exposure, quantified as a 5-day freezing-degree sum (FDS; P = 0.019*). Photoperiod class (Ppd-D1a vs Ppd-D1b) added an additional effect (P = 0.001***). VRN-B1 showed strong genotype effects (P < 0.001***), a modest effect of site on its expression (P = 0.025*), and pronounced associations with microclimate variables (day length, thermal sums, freezing exposure; all P < 0.001***). Directionally, Ppd-D1a backgrounds tended to advance the development while showing earlier apex VRN-A1 peaks. Overall, VRN-A1 expression mainly reflected developmental stage and seasonal forcing, whereas VRN-B1 might be more microclimate-responsive, indicating complementary roles for timing and stress-response plasticity. To isolate causal effects and to further explain these dynamics, targeted sequencing and tests in near-isogenic lines will be needed in future work.

Quantum-inspired machine learning for screening PEG-induced drought stress responses in caraway (Carum carvi L.)Original Paper

Samuel Goitom Misginna, Omar Gaoua, Petra Röszlerová, Musab A Isak, Ondrej Hejna, Patrick Kamulegeya, Eva Jozová, Vladislav Èurn

Czech J. Genet. Plant Breed., 2026, 62(3):170-189 | DOI: 10.17221/18/2026-CJGPB

Drought is a significant factor limiting the growth and early establishment of caraway (Carum carvi L.), a valuable medicinal and aromatic plant. In this study, polyethylene glycol (PEG-6000)-induced osmotic stress assays were combined with statistical and machine learning (ML) approaches to assess early drought responses in five caraway cultivars and breeding materials. Seeds were subjected to four PEG concentrations (0, 5, 10 and 15 %), and key germination and seedling traits, including germination percentage (GP), root length (RL), root fresh weight (RFW), root dry weight (RDW), shoot height (SH), shoot fresh weight (SFW), and shoot dry weight (SDW), were measured. Higher PEG levels caused a sharp, accession-dependent decline in all traits, with germination dropping by 68 % at a 15 % PEG. Cultivars Aprim and H1b2/12 consistently showed better germination, shoot height, and biomass retention across stress levels, while Aklei exhibited lower germination but relatively stronger root growth, suggesting a differential adaptive response under osmotic stress. A linear model (LM) incorporating PEG concentration, accession, and their interaction served as the primary interpretable framework, explaining a large proportion of trait variation (R2 = 0.81–0.94). Principal component analysis (PCA) and correlation analyses further revealed coordinated responses among biomass-related traits and differentiation in early-stage stress responses among accessions. Traditional ML models (MLP and SVR) were compared with quantum-inspired architectures (QiMLP and QiSVR); the quantum-inspired models showed comparable predictive performance in this dataset for certain traits, with QiMLP achieving the highest overall accuracy (R2 = 0.88–0.94). This study presents an integrated phenotyping framework combining controlled stress assays with interpretable statistical modelling to evaluate early growth responses to PEG-induced drought stress in caraway. Overall, the results highlight accession-specific differences in early drought response and provide a useful basis for phenotyping and early-stage screening in caraway breeding.

Impact of nitric oxide on sunflower growth and drought tolerance mechanismsOriginal Paper

Аіdаnа Sugirbеkоva, Mehmet Hamurcu, Anamika Pandey, Mohd. Kamran Khan, Fevzi Elbasan, Zuhal Zeynep Avsaroglu, Ayse Humeyra Omay, Sait Gezgin

Czech J. Genet. Plant Breed., 2025, 61(3):138-150 | DOI: 10.17221/25/2025-CJGPB

Sunflower (Helianthus annuus L.), a globally significant oilseed crop, faces substantial yield losses due to drought stress, a major environmental constraint. In this study, the effects of nitric oxide (NO) to increase drought tolerance in four sunflower genotypes (resistant Irtysh, RAR 56 and sensitive Zarya, RAR 133) showing different stress responses were investigated. Conducted in a controlled hydroponic system, the experiment applied 100 µM NO under 12% polyethylene glycol (PEG)-induced drought, assessing growth, physiological, and biochemical parameters. PEG alone reduced shoot and root growth, relative water content (RWC), and ion levels (K, Ca, Mg, Na), while increasing oxidative stress markers (malondialdehyde (MDA), H2O2, •OH) and electrolyte leakage, particularly in sensitive genotypes. NO application, both alone and with PEG, significantly mitigated these effects, enhancing root fresh weight, RWC, and antioxidant enzyme activities (superoxide dismutase (SOD), peroxidase (POX), catalase (CAT) and glutathione reductase (GR)), while reducing reactive oxygen species (ROS) and lipid peroxidation. Resistant genotypes (Irtysh, RAR 56) exhibited superior stress amelioration. These findings highlight NO’s role as a signalling molecule in augmenting drought resilience through genotype-specific mechanisms. The differential responses among genotypes suggest opportunities for identifying genetic markers associated with NO-mediated drought tolerance, which could guide marker-assisted breeding programs. Additionally, integrating these insights with genomic editing techniques may accelerate the development of drought-resistant sunflower cultivars tailored for water-scarce regions. Future research should optimise NO delivery methods and evaluate field-scale efficacy to advance sustainable sunflower production in water-limited environments.

Transcriptomic profiling of shallots (Allium cepa var. aggregatum) reveals differential gene expression patterns under nitrogen deficiencyOriginal Paper

Tri Joko Santoso, Reflinur Reflinur, Zeeshan Ali, Tri Handayani, Alberta Dinar Ambarwati, Chotimatul Azmi, Atmitri Sisharmini, Aniversari Apriana, Dwinita Wikan Utami, Kristianto Nugroho

Czech J. Genet. Plant Breed., 2026, 62(3):157-169 | DOI: 10.17221/25/2026-CJGPB

Nitrogen (N) is essential for crop productivity, yet excessive fertilisation decreases the nitrogen use efficiency and increases the environmental risks. Despite the economic and medicinal importance of the shallot, its molecular response to N deficiency remains unclear. We performed transcriptome profiling of two cultivars (Bima-0 and Bima 1) under N deficient and N-sufficient conditions. The RNA sequencing identified 438 differentially expressed genes (DEGs). The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed significant modulation of the nitrogen metabolism, amino acid biosynthesis, glutathione metabolism, and stress responses pathways, indicating coordinated metabolic reprogramming under N limitation. The cultivar-specific expression patterns suggested differential adaptive strategies. The quantitative real-time polymerase chain reaction (qRT-PCR) validation of fifteen DEGs confirmed the reliability of the RNA-Seq results. The nitrogen deficiency predominantly repressed the photosynthetic and growth-linked genes while activating the stress-responsive pathways. These findings provide the first transcriptome-level insights into the N deficiency responses in shallots and identify candidate genes and pathways for improving the nitrogen use efficiency (NUE) and developing the sustainable fertiliser management of Allium crops.

Evaluating the discriminatory ability and informativeness of DArTseq markers in a comprehensive set of contemporary European potato varietiesOriginal Paper

Petr Sedlák, Vladimíra Sedláková, Jakub Va¹ek, Ervín Hausvater, Daniela Èílová, Martina Melounová, Jiøí Ptáèek, Petr Dole¾al

Czech J. Genet. Plant Breed., 2026, 62(2):64-75 | DOI: 10.17221/103/2025-CJGPB


High-throughput molecular technology DArTseq generates markers for potential use in molecular breeding of crops. Using DArTseq, we analysed a comprehensive set of 333 European potato varieties reflecting the outcomes of long-term breeding history and representing a potential germplasm for future breeding of potatoes in the Central European region. The varieties were classified according to four factors: region of origin, breeder, earliness and utilisation mode, that may potentially reflect their genetic structure, and for which complete data were publicly available. The DArTseq analysis was performed by the service centre, the Diversity Array Technology (University of Canberra), which generated approximately 38 000 silicoDArT and 64 000 SNP (single nucleotide polymorphism) polymorphic markers. The discriminatory ability of the markers in relation to the factors was confirmed using neighbour-joining and principal coordinate analysis (PCoA), while the informativeness was assessed using the discriminant analysis of principal components (DAPC). The analyses identified the 50 SNPs most strongly associated with each factor, along with their highly probable chromosomal localisation. Herein presented research contributes to the evaluation of potato genetic resources by adding the novel molecular data of active germplasm and implies their future utilisation in genome wide association studies and marker assisted selection.

Whole genome sequencing analysis of two sinensis tea (Camellia sinensis var. sinensis) clones: Assessment of molecular variations to search for breeding markersOriginal Paper

Dwinita Wikan Utami, Adhityo Wicaksono, M. Khais Prayoga, Heri Syahrian, Vitria P. Rahadi, Erdiansyah Rezamela, Budi Martono, Tri Joko Santoso, Nur Kholilatul Izzah, Haris Maulana, Ady Daryanto, Rerenstradika Tizar Terryana (email: rerenstradika.tizar.terryana

Czech J. Genet. Plant Breed., 2026, 62(2):76-88 | DOI: 10.17221/116/2025-CJGPB

Tea (Camellia sinensis (L.) Kuntze) is a globally important crop valued for its flavour diversity and health benefits. Whole-genome sequencing (WGS) was performed to compare genomic variation and functional potential between clone Yabukita and locally adapted clone I.1.93. Using next-generation sequencing, approximately 10× genome coverage was achieved for both clones, with high mapping efficiency (98.24% for Yabukita and 97.88% for clone I.1.93), ensuring reliable downstream analyses. Single nucleotide polymorphism (SNP) analysis revealed distinct genomic patterns, with Yabukita showing a more uniform chromosomal SNP distribution, while clone I.1.93 exhibited higher SNP densities on specific chromosomes, particularly chromosomes 5 and 13. Silent mutations predominated in Yabukita (48.21%), whereas missense mutations were more frequent in clone I.1.93 (57.97%), suggesting greater functional divergence. Most SNPs occurred in non-coding regions, indicating potential regulatory roles. GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed highly similar shared pathways, including photosynthesis and protein interactions, alongside clone-specific enrichment related to photosynthesis in Yabukita and stress responses in clone I.1.93. miRNA profiling identified distinct regulatory patterns, including the clone-specific miR530 in clone I.1.93. Biosynthetic gene cluster analysis further predicted secondary metabolite pathways associated with terpenoid, polyketide, and saccharide biosynthesis. These findings provide valuable genomic insights for tea improvement and breeding programs.

Morpho-molecular diversity study of rice cultivars in BangladeshOriginal Paper

Md Babul Akter, Azad Mosab-Bin, Mohammad Kamruzzaman, Reflinur Reflinur, Nazmun Nahar, Md Sohel Rana, Md Imdadul Hoque, Md Shahidul Islam

Czech J. Genet. Plant Breed., 2022, 58(2):64-72 | DOI: 10.17221/69/2021-CJGPB

Rice is one of the frontline cereals in the world and the major cultivated crop in Bangladesh. A total of eleven simple sequence repeats (SSRs) and thirteen sequence-tagged site (STS) markers were used to characterize twenty-four rice cultivars in Bangladesh. Twenty-four markers generated 60 alleles with 2.5 alleles per locus. The average polymorphism information content (PIC) value was 0.40, while the mean value of heterozygosity, gene diversity, and major allele frequency were recorded as 0.10, 0.48 and 0.62, respectively. However, the SSR markers showed more specificity and a higher discrimination power than the STS markers. The cluster analysis displayed four major clusters with a genetic similarity coefficient value of 0.73. The morphological analyses of the grain identified that Binadhan-20 and BRRI dhan34 had the longest and the shortest seed size, respectively, with a variable correlation between the seed length, width and length/width ratio. The phenol reaction test distinguished seven cultivars as japonica and seventeen cultivars as indica or an intermediate type. All these results regarding the phenotypic data and marker information will be useful for parental selection in modern rice breeding programmes.

Effect of long-term storage on the change in the expression of selected Mal d 1 gene isoforms in the apple cultivar Opal®Original Paper

Ivona ®ïárská, Radek Èmejla

Czech J. Genet. Plant Breed., 2023, 59(3):141-147 | DOI: 10.17221/102/2022-CJGPB

Apples are available all year round since they can be stored for long time. However, the expression of the major apple allergen Mal d 1 can increase in the fruit during storage and incease so the risk of allergies in sensitive consumers. Therefore, we studied the change in the expression of the Mal d 1 gene during storage in the modern cultivar UEB 32642 (known under the brand name Opal®) and the cultivar Gala Brookfield (cv. Gala) as a reference. The cultivars were stored under two different conditions, ultra-low oxygen (ULO) and standard cold conditions. The gene expression was evaluated both in fresh fruits and in fruits stored for four, six, and nine months. Nine isoforms of the gene Mal d 1 with the highest published expression were quantified using real-time PCR. The most expressed isoforms Mal d 1.01, Mal d 1.02 and Mal d 1.06A were found in the fresh and also in the stored fruits. The expression of the Mal d 1.03G and Mal d 1.06D isoforms was higher the sored fruits. Our study confirmed that (i) Opal® had a lower overall expression of the Mal d 1 gene than cv. Gala, both in the fresh and stored fruits; (ii) standard cold storage is superior in preserving lower Mal d 1 levels in Opal®apples compared to the ULO conditions; and (iii) less expressed isoforms may be responsible for the general increase in the Mal d 1 gene expression during storage.

Malting quality molecular markers for barley breedingOriginal Paper

Leona Lei¹ová-Svobodová, Vratislav Psota, Marta Zavøelová, Martin Køí¾, Pavel Maøík, Zdenìk Nesvadba

Czech J. Genet. Plant Breed., 2024, 60(2):70-78 | DOI: 10.17221/72/2023-CJGPB

Barley is one of the world’s most important crops. Barley is used for both food and feed and is important for the production of malt. Malt quality is a complex function of barley genetics, environmental conditions during barley growth, and the technological aspects of the malting process. Due to the high heritability of more than half of the malting parameters, barley can be bred for malting quality. Marker-assisted selection (MAS) is a good way to speed up the breeding process. In this study, nine molecular markers were used to screen 115 barley varieties and breeding lines over a four-year period. The results were compared with malting quality parameters. Multicomponent correlation analysis showed a good correlation (R = 0.63; P ≤ 0.01) between marker screening results and malting quality parameters. In 93 genotypes (80.9%), agreement was found between molecular marker prediction and malting quality determination. Differences between molecular marker screening and malt quality parameters and possible improvements are discussed. The use of molecular markers in MAS is highly appreciated by barley breeders.

Quo vadis, breeding for an efficient root system, in the era of climate change?Review

Tomá¹ Støeda, Jana Hajzlerová, Jhonny Alba-Mejía, Ivana Jovanoviæ, Nicole Frantová, Hana Støedová

Czech J. Genet. Plant Breed., 2024, 60(4):181-211 | DOI: 10.17221/57/2024-CJGPB

Despite all the complications that arise with root research, such as slow, laborious, and unclear genetics, roots are a promising object of interest for breeders because many root traits are compatible with high yield potential. It is a great challenge for further research that there is a wide demand for information on the “hidden half of plant metabolism” from many research fields. We have summarized the main obstacles in root system research and sketched a solution for breeding in field conditions so that the result was more meaningful to the farmer. (i) The most important challenge in root research is linking the functional identification of root system properties with the aboveground parts. (ii) Field breeding is irreplaceable, and methods allowing the evaluation of roots under field conditions are indispensable. (iii) Low heritability of root system trait discourages breeders. However, root properties show broad genotypic variability, allowing the efficient use of these traits as selection criteria. (iv) The root traits are variable, and many fluctuate under the influence of environmental factors, which complicates efforts to define ideotypes and explains the different conclusions obtained by researchers from different environments. The breeding programs targeting the root system are sporadic even in a global context. This is a great reserve for breeding progress in the era of climate change, water scarcity, a possible shift to extensive farming systems, and in the era of environmental programs.

Genetic diversity analysis of Solanum accessions from Czech collections of potato genetic resources using nuclear SSR markersOriginal Paper

Zuzana Rottová, Tereza Anna Javùrková, Petr Sedlák, Jiøí Ptáèek, Eloy Fernández-Cusimamani, Vladimíra Sedláková

Czech J. Genet. Plant Breed., 2026, 62(1):36-48 | DOI: 10.17221/97/2025-CJGPB

The genus Solanum comprises numerous wild and cultivated species that are important for potato breeding. This pilot-scale study aimed to evaluate the genetic diversity in 44 accessions from Solanum sect. Petota, comprising wild species, Andean landraces, and modern cultivars, obtained from the Potato Research Institute Havlíèkùv Brod, Ltd. and the Department of Crop Sciences and Agroforestry at the Faculty of Tropical AgriSciences, Czech University of Life Sciences Prague. Nuclear microsatellite markers (SSR, 29 loci) were applied via five multiplex PCR reactions and analysed using capillary electrophoresis. Binary data matrices were analysed using DARwin software to generate dendrograms reflecting allelic polymorphism. The SSR panel effectively differentiated cultivated accessions from wild types, consistent with the current taxonomy of the genus Solanum, with particularly clear clustering of Andean landraces and modern varieties. However, resolution among wild accessions was limited, likely due to their high genetic complexity and interspecific overlap. These results support the suitability of the SSR panel for analysing diversity in cultivated potatoes. while also highlighting the challenges in resolving wild Solanum taxa. This study contributes to germplasm characterisation and provides a molecular basis for future breeding programmes.

The identification of wheat leaf rust resistance genes and their utilisation value in 42 wheat cultivarsOriginal Paper

Xue Li, Zhanhai Kang, Jiaqi Zhang, Sufen Dong, Man Li, Xing Li

Czech J. Genet. Plant Breed., 2026, 62(1):25-35 | DOI: 10.17221/78/2025-CJGPB

Leaf rust is an important wheat disease that considerably reduces the wheat production in most wheat growing regions worldwide. This study aimed to identify leaf rust resistance genes in 42 wheat varieties to find genetic sources with the broadest spectrum of resistance against leaf rust pathotypes, to enable effective breeding for disease resistance. In this study, 42 wheat cultivars were inoculated with 18 pathotypes of Puccinia triticina Eriks. at the seedling stage to postulate the Lr genes in the cultivars. Resistance to leaf rust at the adult stage was then tested in field trials under natural infection during the 2019 to 2020 cropping seasons at Baoding, Hebei Province. Gene postulation together with molecular marker detection identified ten Lr genes (Lr1, Lr10, Lr14a, Lr26, Lr2a, Lr17, Lr20, Lr34, Lr37, and Lr46) among the 42 accessions.  Lr1 was present in 16 accessions, Lr14a in three accessions, Lr17 in five accessions, Lr2a in five accessions, Lr34 in one accession, Lr10 in two accessions, Lr37 in two accessions and Lr46 in 29 accessions. Additionally, 15 wheat accessions displayed adult-plant resistance or other unknown genes. These results suggest that a high level of leaf rust resistance can be achieved by combining known resistance genes and adult-plant resistance genes in wheat cultivars.

Evaluation of gamma-irradiated Pisum sativum germplasm for agronomic traits and tolerance to Didymella pinodesOriginal Paper

Efi Sarri, Anastasios Katsileros, Sofia Migardou, Panagiotis Viliotis, Ioannis Sidiropoulos, Dimitris Sifnaios, Pavlos Diamantis, Nikolaos Sklavounos, Eleni M. Abraham, Penelope J. Bebeli, Nasya Tomlekova, Dimosthenis Kizis (

Czech J. Genet. Plant Breed., 2026, 62(1):1-13 | DOI: 10.17221/84/2025-CJGPB

Ascochyta blight, caused by a complex of pathogenic fungi including Didymella pinodes, Ascochyta pisi, and Phoma pinodella, is a major disease of field pea (Pisum sativum), causing severe losses through lesions on leaves, stems, and pods. Mutation breeding using gamma irradiation is a non-GMO strategy to induce genetic variation and accelerate the development of improved genotypes. In this study, the M2 generation of the forage pea cultivar Dodoni (Pisum sativum L. var. arvense), derived from M0 seeds irradiated with 100 Gy, was evaluated for tolerance to D. pinodes (CBS 251.47) using a detached-leaf assay under controlled greenhouse conditions. Disease progression was quantified via image-based analysis on the 3rd and 5th days post-infection, calculating diseased area and disease severity index. Extensive phenotypic evaluation was also conducted on 16 families in the greenhouse and 100 families under field conditions, using an augmented incomplete block design. Screening revealed several M2 families with significantly improved tolerance compared to non-irradiated controls. Among these, some individuals combined enhanced resistance with improved yield-related traits, such as higher pod number and biomass, while others exhibited reduced agronomic performance. These findings highlight the phenotypic diversity induced by gamma irradiation and demonstrate the potential to generate dual-purpose pea genotypes with both disease resistance and enhanced productivity, providing valuable material for future breeding of resilient cultivars.

The AhDREB transgene expression activates NtP5CS and NtSUSY, promoting osmotic adjustment in transgenic tobacco under salt stressOriginal Paper

Thuy Thi Xuan Vi, Dang Xuan Hoang, Tra Thi Nguyen, Ngoc Bich Pham, Quan Huu Nguyen, Mau Hoang Chu

Czech J. Genet. Plant Breed., 2026, 62(2):89-101 | DOI: 10.17221/124/2025-CJGPB

Soil salinity is a major environmental constraint that limits the growth and productivity of peanut (Arachis hypogaea L.), a legume adapted to mildly acidic soils but highly sensitive to saline–alkaline conditions. Dehydration-Responsive Element Binding (DREB) transcription factors are key regulators of plant responses to abiotic stresses. In this study, the AhDREB gene from peanut was introduced into tobacco (Nicotiana tabacum) to examine its functional role under salt stress. The transgenic lines (L32.2 and L37.2) exhibited strong induction of AhDREB expression upon exposure to 150 and 250 mM NaCl, with transcript levels increasing up to 2.34-fold compared with untreated controls (< 0.001). Quantitative RT-PCR analysis revealed that AhDREB enhanced the transcription of two osmolyte-related genes, NtP5CS and NtSUSY. Under saline conditions, the expression of these genes was 1.20–1.89-fold higher in transgenic lines than in wild-type (WT) plants and 4.74–7.66-fold higher than in non-stress conditions (P < 0.001). Consistently, both lines accumulated greater amounts of proline and soluble sugars, showing 2.09–2.30-fold and 2.40–4.70-fold increases, respectively, compared with the WT. Relative to non-stress conditions, proline and sugar contents increased by 3.59–5.47 fold and 3.75–7.65-fold, respectively. Line L37.2 accumulated higher proline levels, whereas L32.2 exhibited greater sugar content, indicating distinct osmolyte regulation patterns. Overall, the AhDREB gene enhances salt tolerance in tobacco by transcriptionally activating osmolyte biosynthetic pathways and improving cellular osmotic adjustment, providing molecular evidence for its potential application in developing stress-tolerant peanut cultivars.

Synergistic effects of low IAA and GA concentrations promote dehiscence-zone separation in vegetable soybeanOriginal Paper

Bingjie Tu, Changkai Liu, Qiuying Zhang, Xiaobing Liu, Nan Xu

Czech J. Genet. Plant Breed., 2026, 62(3):190-199 | DOI: 10.17221/37/2026-CJGPB

Pod dehiscence, also known as pod shattering, is the process by which mature pods open and release their seeds at physiological maturity. In vegetable soybean (Glycine max L.), premature seed release from mature pods is a major cause of yield loss during seed production. As pod dehiscence occurs within the dehiscence zone, understanding the physiological mechanisms governing its formation and degradation is essential. To investigate these mechanisms, we compared the activities of pectinase, polygalacturonase (PG), cellulase, indole-3-acetic acid (IAA), gibberellin (GA), abscisic acid (ABA) and zeatin (ZA) in the pod ventral sutures of dehiscent vegetable soybean and indehiscent grain soybeans. The ventral sutures of dehiscent vegetable soybean exhibited significantly higher activities of pectinase, polygalacturonase, and cellulase, but lower concentrations of IAA and GA than those of indehiscent grain soybean. Reduced levels of IAA and GA in the dehiscence zone were associated with increased activities of cellulase, pectinase, and polygalacturonase activities, which may accelerate cell wall degradation and promote lignification, thereby promoting pod dehiscence.

Genetic diversity of selected Malaysian rice accessions using microsatellite markersOriginal Paper

Shahril Ab Razak, Alny Marlynni Abd Majid, Rahiniza Kamaruzaman, Norliza Abu Bakar, Rabiatul Adawiah Zainal Abidin, Yun Shin Sew, Norfarhan Mohd-Assaad, Asmuni Mohd Ikmal, Noraziyah Abd Aziz Shamsudin (email: nora_aziz@ukm.

Czech J. Genet. Plant Breed., 2026, 62(3):146-156 | DOI: 10.17221/133/2025-CJGPB

Genetic diversity of plant genetic resources provides the foundation for breeding programmes aimed at developing high-yielding rice varieties with tolerance to biotic and abiotic stresses. Given the abundance of available genetic resources, efficient approaches for their characterisation are essential. In this study, 182 Malaysian rice accessions representing different maturity groups were characterised using 20 polymorphic simple sequence repeat (SSR) markers. The analysis identified 183 alleles, ranging from two (RM507) to 22 (RM154), with an average of 9.15 alleles per locus. Observed and expected heterozygosity ranged from 0.000 to 0.506 and 0.319 to 0.864, respectively. Polymorphism information content (PIC) values ranged from 0.2744 (RM495) to 0.8475 (RM154), with an average of 0.6216 per locus. Unweighted pair group method with arithmetic mean (UPGMA) analysis revealed two major groups. In general, the accessions were clustered according to their adaptive ecosystem type, with most lowland varieties, including lowland breeding lines (92.4%), assigned to Group I, whereas most upland varieties (86.7%) belonged to Group II. This grouping pattern was supported by STRUCTURE analysis, which identified K = 2 as the optimal number of clusters, indicating that the studied accessions were structured into two major genetic groups. Principal coordinate analysis (PCoA) further supported this grouping pattern, with the first three axes explaining 39.63% of the total variation. Analysis of molecular variance (AMOVA) showed that 31% of the total variation occurred among populations, 63% among accessions, and 6% within accessions. The results also indicated the possible presence of duplicate accessions within the collection. This study provides valuable insights for future breeding programmes aimed at developing high-yielding rice varieties with a broad genetic base and supports the effective management and conservation of rice genetic resources.

Role of herbicide-tolerant (HT) rice in the weed management of direct seeded crop: Challenges and opportunitiesReview

Jenifer Sylvia Johnson Sunder Singh, Thangaraj Kandasamy, Manonmani Swaminathan, Raveendran Muthurajan, Murali Arthanari Palanisamy, Vijayalakshmi Dhashnamurthi, Sudha Manickam

Czech J. Genet. Plant Breed., 2024, 60(4):159-180 | DOI: 10.17221/26/2024-CJGPB

Food insecurity which has been a global threat, forces researchers to develop crops with increased productivity even under varying climatic conditions. Rice, being a significant staple and strategic crop, helps ensure economic stability, food, and nutritional security globally. It meets 20% of the calorie requirement of people residing all over the world. Lately, rice cultivation and research have been facing hitherto unprecedented difficulties in the context of climate-induced water scarcity and dwindling resources of manpower, arable land, etc. In this regard, direct seeded rice (DSR) as a resource conservation technique is gaining popularity as a potential alternative to conventional transplanting with reduced input requirement, reduced methane and CO2 emission, increased adaptability to climate change, and increased economic returns. The weed menace in DSR prevents it from reaching its fruitful attainment to a significant level. DSR highly depends on herbicide for weed control as manual weeding and other cultural practices are labour intensive which again meets a setback of crop injury (non-selective herbicide) and resistant weeds (selective herbicides). Herbicide-tolerant (HT) rice could be an effective and long-term solution for weed management in DSR. Three HT rice systems, viz., imidazolinones, glyphosate, and glufosinate, have already been developed in this context. This review gives an insight into the need for HT rice in DSR, its production system, limitations, and stewardship guidelines for proper weed management in rice.

Agronomic and pod traits in relation to pod shattering in cultivated soybeansOriginal Paper

Bingjie Tu, Qingying Zhang, Xiaobing Liu, Shaopeng Yu, Nan Xu, Jia Liu, Changkai Liu

Czech J. Genet. Plant Breed., 2025, 61(2):67-76 | DOI: 10.17221/119/2024-CJGPB

Pod dehiscence or pod shattering from mature soybean (Glycine max L.) is one of the most outstanding disadvantages in domesticated cultivars. Pod shattering in relation to 16 quantitative traits and 3 qualitative traits among 140 cultivars of vegetable soybeans, grain soybeans and small-grain soybeans was evaluated over two years. We found the pod shattering percentage is positively correlated with the number of productive branches, pod width, pod length, pod area, 100-seed weight, 1-seeded-pod percentage, 2-seeded-pod percentage and seed protein content, but negatively correlated with the plant height, pod height at the bottom, number of nodes on the main stem, 3-seeded-pod percentage, 4-seeded-pod percentage and seed oil content. The pod shattering percentage in vegetable soybeans is remarkably high, reaching up to 93%, 7.8 times higher than that of grain soybeans. A schematic model of the characteristics for shatter-susceptible and shatter-resistant soybean cultivars is proposed. The pod shattering in vegetable soybeans is related to the “umbrella-shaped” architecture and pod size. It is suggested to select lines with more 2-seeded and 3-seeded pods for vegetable soybeans, but a higher seed oil content and greater node number on the main stem for grain soybeans and small-grain soybeans, to avoid pod shattering in future breeding programmes.

The insertion of an ancestral gene in Nicotiana tabacum plants reduces free radicals during saline irrigationOriginal Paper

Claudia Marissa Calderón Torres, Victoria Abril Mancilla Galván, Miguel Murguía Romero

Czech J. Genet. Plant Breed., 2025, 61(1):43-49 | DOI: 10.17221/107/2024-CJGPB

Transgenic organisms modified with ancestral genes for nitrogen metabolism are rare. Previously, it was reported that genetically modified Nicotiana tabacum with the ARO4 gene of aromatic amino acid synthesis from the yeast Debaryomyces hansenii increases its growth during moderate salt stress. In this investigation, it was explored if the changes in the expression of the gene DhARO4 in Nicotiana tabacum, during saline irrigation, are related to the chlorophyll content and the total reactive oxygen species production. Seedlings of transgenic and wild type Nicotiana tabacum germinated in standard conditions were divided into two irrigation groups, with 100 mM of NaCl and with tap water; and, after 50 days, in the non-senescent adult leaves of the plants, the total chlorophyll a and b and the total chlorophyll content were determined by spectrophotometry and the reactive oxygen species production (•OH, 1O2, H2O2) was quantified by a 2',7'-dichlorodihydrofluorescein assay. The expression of the DhARO4 gene was verified with a salt shock of 100 mM of NaCl for 24 hours in the transgenic and wild type plants in the tap water irrigation group. The DhARO4 gene transcript increased (P < 0.05) in the transgenic plant; meanwhile, the average concentration of chlorophyll a increased (P < 0.05), and the average production of reactive oxygen species decreased (P < 0.05).

Reciprocal hybridisation of Aloe species (Aloe arborescens with A. vera) and their characterisation in a highland region of VenezuelaOriginal Paper

José Imery-Buiza, Wendy Ozols-Narbona

Czech J. Genet. Plant Breed., 2025, 61(2):100-109 | DOI: 10.17221/7/2025-CJGPB

Aloe vera and A. arborescens are succulent plants widely used in cosmetics, pharmaceuticals, and food supplements. The objective of this study was to perform interspecific crosses and agronomically characterise three genotypes cultivated in a Venezuelan highland region (altitude 1 727 m, 13–17.9 °C). Successful hybridisation was achieved only when A. arborescens pollen (P1) was used on A. vera pistils (P2), whereas the reciprocal cross was largely unsuccessful. Hybrid seed germination reached 11.86%, and adult hybrids exhibited significant vegetative superiority over P1, particularly in leaf volume, leaf weight, and flower number. The progeny outperformed both parents in leaf base width and lateral tooth size, thereby enhancing its ornamental value. The expected 2n = 2x = 14 karyotype was confirmed in the root meristems of hybrids. The analysis of leaf pulp processing indicated that the hybrid was promising for juice production (39.8% yield, 1 203 ppm acemannan), thus highlighting its potential for agro-industrial applications in tropical highlands or comparable temperate regions. Other agronomic traits, including number, thickness, colour, and shape of leaves; sprouting of stem branches and basal suckers, flowering period, inflorescence, eggs/ovary, and details of the colour and dimensions of bracts, perianth, pedicel, and ovary, were also evaluated.

Microsatellite markers as a useful tool for species identification and assessment of genetic diversity of the Tilia species in the Czech RepublicOriginal Paper

Pavlína Máchová, Helena Cvrèková, Olga Trèková, Kateøina Vítová, Johana Pechaèová, Václav Buriánek, Petr Madìra, Kateøina Hou¹ková, Tomá¹ Vyhnánek, Pavel Hanáèek

Czech J. Genet. Plant Breed., 2026, 62(1):14-24 | DOI: 10.17221/102/2025-CJGPB

Diagnostic morphological traits distinguishing Tilia cordata and T. platyphyllos are not always apparent. Precise species identification is crucial for conservation management and for establishing genetic resources of forest reproductive material. In this study, we employed fifteen microsatellite (SSR) markers to identify diagnostic loci for reliable species discrimination between T. cordata and T. platyphyllos species and to evaluate the genetic diversity. A total of 250 trees were sampled from eight natural autochthonous populations of T. cordata and T. platyphyllos in the Czech Republic, and additional ten individuals of T. tomentosa were included for comparison. Markers Tc8 and Tc918 were identified as diagnostic, exhibiting species-specific alleles for T. cordata and T. platyphyllos. Contrary to the previously published results, we obtained PCR amplicons at locus Tc918 with an allele size of 226 bp in T. cordata. An analysis of the fifteen SSR loci revealed a high level of genetic variability in both the T. cordata and T. platyphyllos populations. No clonally identical genotypes were detected across the eight study sites. The genetic differentiation (Fst) was higher between T. platyphyllos and T. tomentosa (0.316) than between T. platyphyllos and T. cordata (0.205). Bayesian clustering further revealed distinct genetic structures for T. cordata, T. platyphyllos, and T. tomentosa.

Expression and analysis of StNR and StNiRs, key enzyme genes of nitrogen assimilation in potato (Solanum tuberosum L.) with different nitrogen efficienciesOriginal Paper

Yuzhu Han, Zhijun Han, Yue Lu, Zhongcai Han, Jiayue Zhang, Jingying Zhang, Hongyu Qiao, Hongxia He

Czech J. Genet. Plant Breed., 2025, 61(4):193-209 | DOI: 10.17221/22/2025-CJGPB

The potato is a pivotal food crop on a global scale. Nitrate reductase (NR) and nitrite reductase (NiR) are the key enzymes in nitrogen assimilation. In previous research, we found that the nitrogen assimilation process was effectively regulated by StNR and StNiRs in potato and that there were significant differences in nitrogen utilisation efficiency between different potato varieties. In this study, three potato variants with different nitrogen use efficiency (NUE) were subjected to various nitrogen supply levels and photoperiod treatments. The results indicated that the relative expression levels of StNR and StNiRs in their leaves and roots, along with the enzyme activity of NR and NiR, were proportional to the nitrogen supply levels and photoperiod. This study further clarified the expression patterns of StNR and StNiRs, as well as the enzyme activity changes of NR and NiR in leaves and roots under different nitrogen supply levels and different photoperiod treatments. This provides a theoretical basis for further in-depth exploration of the specific functions related to nitrogen absorption and assimilation efficiency in potato.

Genetic diversity assessment of hydrogen cyanide, total carotenoid content, and dry matter content in biofortified cassava using trait-linked SNP markersOriginal Paper

Bismark Anokye, Peter Amoah, Bardee Wrojay Potter, Abdoul-Razak Oumarou Mahamane, Theophilus Adu-Gyamfi, Levitikos Dembure, Nezif Abajebal Abadura, Bunmi Olasanmi, Elizabeth Parkes

Czech J. Genet. Plant Breed., 2026, 62(2):102-114 | DOI: 10.17221/121/2025-CJGPB

Assessing of genetic diversity is essential for identifying useful alleles for crop improvement. This study evaluated genetic diversity among two cassava breeding populations for total carotenoid content (TCC), dry matter content (DMC), and hydrogen cyanide (HCN) concentration using trait-linked single nucleotide polymorphism (SNP) markers. A total of 360 genotypes were analysed, including 261 from the IITA breeding programme (Population 1), 23 progenitor lines, and 76 from the University of Ibadan Cassava (UIC) breeding programme (Population 2). Minor allele frequency (MAF), gene diversity (GD), observed heterozygosity (He), and polymorphic information content (PIC) were computed. Principal component analysis (PCA) and hierarchical clustering were performed to examine genetic variation and population structure. Call rates were high (96–100%). MAF ranged from 0.00 to 0.50, with mean values of 0.28, 0.28, and 0.29 for Population 1, Population 2, and progenitors, respectively. GD averaged 0.36, 0.36, and 0.35 across these groups. Observed heterozygosity was 0.42, 0.41, and 0.43, while PIC values averaged 0.29, 0.27, and 0.27 for Population 1, Population 2, and progenitors, respectively. PCA and clustering analyses grouped the genotypes into three clusters containing 257, 88, and 15 genotypes. The first two principal components explained 39.1% of the total genetic variation. The results indicate substantial genetic diversity among the studied genotypes, suggesting strong potential for allele pyramiding and highlighting the informativeness of the SNP markers used.

The 90th Birthday of RNDr. Erik Schwarzbach, Dr. agr. habil. (*6 April 1936)Biographical Notice

Antonín Dreiseitl, Vìra Kroftová

Czech J. Genet. Plant Breed., 2026, 62(2):115-116 | DOI: 10.17221/31/2026-CJGPB

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Genetic diversity of some autochthonous white grape varieties from Romanian germplasm collectionsOriginal Paper

Anamaria Mirabela Ilina Dumitru, Andreea Elena Manolescu, Dorin Ioan Sumedrea, Carmen Florentina Popescu, Sina Cosmulescu

Czech J. Genet. Plant Breed., 2023, 59(2):55-66 | DOI: 10.17221/45/2022-CJGPB

We investigated the phenotypic and genetic diversity among 25 grapevine accessions of white grape maintained in a germplasm collection ex situ. The selected varieties were characterised using standardised ampelographic descriptors and microsatellite markers to obtaintheir complete description. The ampelographic analysis based on 24 OIV descriptors and the obtained first dendrogram based on common features, revealed the extent of the phenotypic diversity ranging from 0.29 (between Coarnã albã and Chardonnay) to 0.92 (between Crâmpoºie and Cioinic), without any connection with their supposed origin or the current geographic area of distribution. The SSR allelic analysis with nine standard markers proved and confirmed its high discrimination potential for genotype identification and diversity. The second cluster analysis aimed to evaluate the genetic relationships among analysed accessions,based on Dice’s similarity coefficient, revealed two groups of varieties: the first group (A) included twelve accessions with a degree of similarity between 0.37 and 0.5. The second (B) included eleven accessions, with a similarity degree between 0.33 and 0.67. The genotypic cluster analysis showed a distinct lower similarity between the Majarcã albã variety and all the varieties from the first group, and between Busuioacã de Bohotin and all the analysed varieties. The phenotypic and genetic matrices and dendrograms, although not correlated, were complimentary and provided valuable information about the diversity of the grapevine genotypes and the identification of the synonyms.

Genetic diversity among coloured cotton genotypes in relation to their fibre colour and ploidy level based on SSR markersOriginal Paper

Revanasiddayya, Jayaprakash Mohan Nidagundi, Bashasab Fakrudin, Prakash Kuchanur, Lingappa Neelagiri Yogeesh, Shivanand Hanchinal, Talagunda Chandrashekar Suma, Gururaj Sunkad, Bharamappanavara Muralidhara, Dod

Czech J. Genet. Plant Breed., 2024, 60(1):12-24 | DOI: 10.17221/12/2023-CJGPB

Genetic diversity is referred to as any variation at the phenotypic, DNA or genomic level of an individual, population or species. The appraisal of diversity is important to understand its pattern and evolutionary relationships between germplasms or genotypes, which will aid in sampling the genetic resources in a more systematic manner for conservation and crop improvement. The present study employed 50 simple sequence repeat (SSR) markers linked to the yield and fibre quality/colour traits for estimating the genetic diversity in 33 cotton genotypes of diploid and tetraploid species differing in fibre colour. The diversity analysis was performed in GenAlEx (Ver. 6.41) and Powermarker (Ver. 3.25) while DARwin (Ver. 6.0.21) software was used to establish the phylogenetic relationships following neighbour-joining (NJ) and unweighted pair group method with arithmetic (UPGMA) mean method. Markers generated 186 polymorphic loci as genotypic data with an average of 3.72 alleles and an average polymorphic information content (PIC) value of 0.59 per SSR locus. The NJ and UPGMA grouped 33 genotypes into three major clusters I, II and III consisting of 21 tetraploid Gossypium hirsutum, 10 G. arboreum coloured and 2 white cotton genotypes, respectively. In the PCA, the first two components (PC1 and PC2) explained 74.69% of the variation and the biplot plotted the 33 genotypes in three groups. The study established the diverse nature of 33 cotton genotypes based on their fibre colour and ploidy level. With confirmation of the prevalent genetic diversity, we suggest that hybridisation can be planned among diverse genotypes to unleash greater variation in the fibre colour or to derive superior cross combinations.

Exploring strigolactones for inducing abiotic stress tolerance in plantsReview

Mohd. Kamran Khan, Anamika Pandey, Mehmet Hamurcu, Tomá¹ Vyhnánek, Sajad Majeed Zargar, Abdullah Kahraman, Ali Topal, Sait Gezgin

Czech J. Genet. Plant Breed., 2024, 60(2):55-69 | DOI: 10.17221/88/2023-CJGPB

Strigolactones (SLs) are a comparatively novel class of phytohormones that are involved in the maintenance of plant architecture with key regulation of lateral branching. They are also reported to play an important role in regulating plant responses to various abiotic stresses. The potential of SLs to improve crop resilience and productivity needs to be effectively translated into agriculture. Therefore, both the endogenous biosynthesis of SLs and their exogenous application need to be thoroughly investigated to understand and exploit the mechanism underlying the alleviation of abiotic stress responses. Although several reviews have emphasised the biosynthesis of SLs in plants under abiotic stress, the mechanism underlying the alleviation of stress responses upon exogenous application has been less explored. Accordingly, in this review, although we have briefly discussed the beneficial effects of endogenous production of SLs in different sections, our main focus is to summarise the influence of exogenous SLs on the growth and development of different plant species grown under various abiotic stresses, including drought, nutrient, heavy metal, and salinity stress. Apart from providing an overview of the transcriptomic studies conducted to observe the alleviating effects of SLs on abiotic stress responses, the research gaps in this field were briefly discussed. The review provides insight for researchers to conduct further research on SLs and fill the gap so that they can be effectively used for sustainable agriculture.

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