Key message Recent developments in understanding the distribution and distinctive features of rec... more Key message Recent developments in understanding the distribution and distinctive features of recombination hotspots are reviewed and approaches are proposed to increase recombination frequency in coldspot regions. Abstract Recombination events during meiosis provide the foundation and premise for creating new varieties of crops. The frequency of recombination in different genomic regions differs across eukaryote species, with recombination generally occurring more frequently at the ends of chromosomes. In most crop species, recombination is rare in centromeric regions. If a desired gene variant is linked in repulsion with an undesired variant of a second gene in a region with a low recombination rate, obtaining a recombinant plant combining two favorable alleles will be challenging. Traditional crop breeding involves combining desirable genes from parental plants into offspring. Therefore, understanding the mechanisms of recombination and factors affecting the occurrence of meiotic recombination is important for crop breeding. Here, we review chromosome recombination types, recombination mechanisms, genes and proteins involved in the meiotic recombination process, recombination hotspots and their regulation systems and discuss how to increase recombination frequency in recombination coldspot regions.
Rice (Oryza sativa) is a staple food that feeds more than half the world population. As rice is h... more Rice (Oryza sativa) is a staple food that feeds more than half the world population. As rice is highly sensitive to soil salinity, current trends in soil salinization threaten global food security. To better understand the mechanistic basis of salinity tolerance in rice, three contrasting rice cultivars-Reiziq (tolerant), Doongara (moderately tolerant), and Koshihikari (sensitive)were examined and the differences in operation of key ion transporters mediating ionic homeostasis in these genotypes were evaluated. Tolerant varieties had reduced Na + translocation from roots to shoots. Electrophysiological and quantitative reverse transcription PCR experiments showed that tolerant genotypes possessed 2-fold higher net Na + efflux capacity in the root elongation zone. Interestingly, this efflux was only partially mediated by the plasma membrane Na + /H + antiporter (OsSOS1), suggesting involvement of some other exclusion mechanisms. No significant difference in Na + exclusion from the mature root zones was found between cultivars, and the transcriptional changes in the salt overly sensitive signaling pathway genes in the elongation zone were not correlated with the genetic variability in salinity tolerance amongst genotypes. The most important hallmark of differential salinity tolerance was in the ability of the plant to retain K + in both root zones. This trait was conferred by at least three complementary mechanisms: (1) its superior ability to activate H +-ATPase pump operation, both at transcriptional and functional levels; (2) reduced sensitivity of K + efflux channels to reactive oxygen species; and (3) smaller upregulation in OsGORK and higher upregulation of OsAKT1 in tolerant cultivars in response to salt stress. These traits should be targeted in breeding programs aimed to improve salinity tolerance in commercial rice cultivars.
Wild rice species provide a rich source of genetic diversity for possible introgression of salini... more Wild rice species provide a rich source of genetic diversity for possible introgression of salinity stress tolerance in cultivated rice. We investigated the physiological basis of salinity stress tolerance in Oryza species by using six rice genotypes (Oryza sativa L.) and four wild rice species. Three weeks of salinity treatment significantly (P < 0.05) reduced physiological and growth indices of all cultivated and wild rice lines. However, the impact of salinity-induced growth reduction differed substantially among accessions. Salt tolerant accessions showed better control over gas exchange properties, exhibited higher tissue tolerance, and retained higher potassium ion content despite higher sodium ion accumulation in leaves. Wild rice species showed relatively lower and steadier xylem sap sodium ion content over the period of 3 weeks analysed, suggesting better control over ionic sodium xylem loading and its delivery to shoots with efficient vacuolar sodium ion sequestration. Contrary to this, saline sensitive genotypes managed to avoid initial Na + loading but failed to accomplish this in the long term and showed higher sap sodium ion content. Conclusively, our results suggest that wild rice genotypes have more efficient control over xylem sodium ion loading, rely on tissue tolerance mechanisms and allow for a rapid osmotic adjustment by using sodium ions as cheap osmoticum for osmoregulation.
Salt stress is an ever-present threat to rice production worldwide. Rice salinity tolerance is co... more Salt stress is an ever-present threat to rice production worldwide. Rice salinity tolerance is complex, both genetically and physiologically. The success and effectiveness in selecting salt-tolerant rice variety require the identification of QTL for the tolerance and closely linked molecular markers. In the present study, a RIL population consisting of 148 lines, derived from a cross between IR29 (salt-sensitive) and Pokkali (salt-tolerant), was used to identify new QTL for salt tolerance and investigate the relationships between salt stress caused injury and the changes in different physiological and morphological traits at the seedling stage. 14,470 high-quality SNP markers generated by the Rice 56K SNP array were converted to 1,467 bin markers for linkage mapping. A high-density genetic linkage map covering 1,680.9 cM was constructed, with the physical to genetic distance ratio being 222 Kb/cM. In total, 23 QTL for different salt tolerance indices were identified, including the previously reported Saltol which is currently used in breeding programmes. Three QTL for salt injury score (SIS) were located on chromosomes 1, 4 and 12, all being closely related to the long-distant Na + transport from roots to shoots. These QTL showed additive effects, thus can be effectively used in breeding programme to pyramid various tolerance genes.
Zinc (Zn) de ciency is a common limiting factor in agricultural soils that signi cantly reduces b... more Zinc (Zn) de ciency is a common limiting factor in agricultural soils that signi cantly reduces both yield and nutritional quality of agricultural produce. Exploring the quantitative trait loci (QTL) for shoot and grain Zn accumulation would help to develop barley cultivars with greater Zn accumulation e ciency. In this study, two glasshouse experiments were conducted by growing plants under adequate and low Zn supply. From the preliminary screening of ten barley cultivars, Sahara (0.05 mg/pot) and Yerong (0.06 mg/pot) showed the lowest difference while Franklin (0.16 mg/pot) had the highest difference in shoot Zn accumulation as a result of the change in Zn supply for plant growth. Therefore, the double haploid (DH) population derived from Yerong x Franklin was selected for the identi cation of QTL for shoot mineral accumulation and biomass production. A major QTL hotspot was detected on chromosome 2H between 31.91-73.12 cM encoding genes for regulating shoot mineral accumulations of Zn, Fe, Ca, K and P, and the biomass. Further investigation demonstrated that 16 potential candidate genes for mineral accumulation, in addition to a single candidate gene for shoot biomass were found in the identi ed QTL region of this study. The genomic region identi ed in this study could be a useful resource for the improvement of mineral nutrient composition and yield potential in future barley breeding programs.
SummaryThe green revolution was based on genetic modification of the gibberellin (GA) hormone sys... more SummaryThe green revolution was based on genetic modification of the gibberellin (GA) hormone system with “dwarfing” gene mutations that reduces GA signals, conferring shorter stature, thus enabling plant adaptation to modern farming conditions. Strong GA‐related mutants with shorter stature often have reduced coleoptile length, discounting yield gain due to their unsatisfactory seedling emergence under drought conditions. Here we present gibberellin (GA) 3‐oxidase1 (GA3ox1) as an alternative semi‐dwarfing gene in barley that combines an optimal reduction in plant height without restricting coleoptile and seedling growth. Using large‐scale field trials with an extensive collection of barley accessions, we showed that a natural GA3ox1 haplotype moderately reduced plant height by 5–10 cm. We used CRISPR/Cas9 technology, generated several novel GA3ox1 mutants and validated the function of GA3ox1. We showed that altered GA3ox1 activities changed the level of active GA isoforms and consequently increased coleoptile length by an average of 8.2 mm, which could provide essential adaptation to maintain yield under climate change. We revealed that CRISPR/Cas9‐induced GA3ox1 mutations increased seed dormancy to an ideal level that could benefit the malting industry. We conclude that selecting HvGA3ox1 alleles offers a new opportunity for developing barley varieties with optimal stature, longer coleoptile and additional agronomic traits.
Background: Aluminium (Al) toxicity is the main factor limiting the crop production in acid soils... more Background: Aluminium (Al) toxicity is the main factor limiting the crop production in acid soils and barley (Hordeum vulgare L.) is one of the most Al-sensitive of the small-grained cereals. The major gene for Al tolerance in barley is HvAACT1 (HvMATE) on chromosome 4H which encodes a multidrug and toxic compound extrusion (MATE) protein. The HvAACT1 protein facilitates the Al-activated release of citrate from root apices which protects the growing cells and enables root elongation to continue. A 1 kb transposable element-like insert in the 5' untranslated region (UTR) of HvAACT1 is associated with increased gene expression and tolerance and a PCR-based marker is available to score for this insertion. Results: We screened a wide range of barley genotypes for Al tolerance and identified a moderately tolerant Chinese genotype named CXHKSL which did not show the typical allele in the 5' UTR of HvAACT1 associated with tolerance. We investigated the mechanism of Al tolerance in CXHKSL and concluded it also relies on the Alactivated release of citrate from roots. Quantitative trait loci (QTL) analysis of double haploid lines generated with CXHKSL and the Al-sensitive variety Gairdner mapped the tolerance locus to the same region as HvAACT1 on chromosome 4H. Conclusions: Our results show that the Chinese barley genotype CXHKSL possesses a novel allele of the major Al tolerance gene HvAACT1.
Key message This study demonstrates how identification of genes underpinning disease-resistance Q... more Key message This study demonstrates how identification of genes underpinning disease-resistance QTL based on differential expression and SNPs can be improved by performing transcriptomic analysis on multiple near isogenic lines. Abstract Transcriptomic analysis has been widely used to understand the genetic basis of a trait of interest by comparing genotypes with contrasting phenotypes. However, these approaches identify such large sets of differentially expressed genes that it proves difficult to isolate which genes underpin the phenotype of interest. This study tests whether using multiple near isogenic lines (NILs) can improve the resolution of RNA-seq-based approaches to identify genes underpinning diseaseresistance QTL. A set of NILs for a major effect Fusarium crown rot-resistance QTL in barley on the 4HL chromosome arm were analysed under Fusarium crown rot using RNA-seq. Differential gene expression and single nucleotide polymorphism detection analyses reduced the number of putative candidates from thousands within individual NIL pairs to only one hundred and two genes, which were differentially expressed or contained SNPs in common across NIL pairs and occurred on 4HL. Our findings support the value of performing RNA-seq analysis using multiple NILs to remove genetic background effects. The enrichment analyses indicated conserved differences in the response to infection between resistant and sensitive isolines suggesting that sensitive isolines are impaired in systemic defence response to Fusarium pseudograminearum.
Models are key tools in our quest to better understand the impacts of soil waterlogging on plant ... more Models are key tools in our quest to better understand the impacts of soil waterlogging on plant growth and crop production. Here, we reviewed the state of the art of modeling approaches and compared the conceptual design of these models with recent experimental findings. We show that many models adopt an aeration stress (AS) principle where surplus water reduces air-filled porosity, with implications for root growth. However, subsequent effects of AS within each model vary considerably. In some cases, AS inhibits biomass accumulation (e.g. AquaCrop), altering processes prior to biomass accumulation such as light interception (e.g. APSIM), or photosynthesis and carbohydrate accumulation (e.g. SWAGMAN Destiny). While many models account for stage-dependent waterlogging effects, few models account for experimentally observed delays in phenology caused by waterlogging. A model intercomparison specifically designed for long-term waterlogged conditions (APSIM-Oryza) with models developed for dryland conditions with transient waterlogging would advance our understanding of the current fitness for purpose of exsiting frameworks for simulating transient waterlogging in dryland cropping systems. Of the point-based dynamic models examined here, APSIM-Soybean and APSIM-Oryza simulations most closely matched with the observed data, while GLAM-WOFOST achieved the highest performance of the spatial-regional models examined. We conclude that future models should incorporate waterlogging effects on genetic tolerance parameters such as (1) phenology of stress onset, (2) aerenchyma, (3) root hydraulic conductance, (4) nutrient-use efficiency, and (5) plant ion (e.g. Fe/Mn) tolerance. Incorporating these traits/effects into models, together with a more systematic model intercomparison using consistent initialization data, will significantly improve our understanding of the relative importance of such factors in a systems context, including feedbacks between biological factors, emergent properties, and sensitive variables responsible for yield losses under waterlogging.
Salinity tolerance is a complex traitboth physiologically and geneticallyand the issue of which m... more Salinity tolerance is a complex traitboth physiologically and geneticallyand the issue of which mechanism or trait has bigger contribution towards the overall plant performance is still hotly discussed in the literature. In this work, a broad range of barley (Hordeum vulgare L. and Hordeum spontaneum L.) genotypes contrasting in salinity stress tolerance were used to investigate the causal link between plant stomatal characteristics, tissue ion relations, and salinity tolerance. In total, 46 genotypes (including two wild barleys) were grown under glasshouse conditions and exposed to moderate salinity stress (200 mM NaCl) for 5 weeks. The overall salinity tolerance correlated positively with stomata density, leaf K + concentration and the relative contribution of inorganic ions towards osmotic adjustment in the shoot. At the same time, no correlation between salinity tolerance and stomatal conductance or leaf Na + content in the shoot was found. Taken together, these results indicate the importance of increasing stomata density as an adaptive tool to optimise efficiency of CO 2 assimilation under moderate saline conditions, as well as benefits of the predominant use of inorganic osmolytes for osmotic adjustment in barley. Another finding of note was that wild barleys showed rather different strategies dealing with salinity, as compared with cultivated varieties.
This work investigated the importance of the ability of leaf mesophyll cells to control K(+) flux... more This work investigated the importance of the ability of leaf mesophyll cells to control K(+) flux across the plasma membrane as a trait conferring tissue tolerance mechanism in plants grown under saline conditions. Four wheat (Triticum aestivum and Triticum turgidum) and four barley (Hordeum vulgare) genotypes contrasting in their salinity tolerance were grown under glasshouse conditions. Seven to 10-day-old leaves were excised, and net K(+) and H(+) fluxes were measured from either epidermal or mesophyll cells upon acute 100 mM treatment (mimicking plant failure to restrict Na(+) delivery to the shoot) using non-invasive microelectrode ion flux estimation (the MIFE) system. To enable net ion flux measurements from leaf epidermal cells, removal of epicuticular waxes was trialed with organic solvents. A series of methodological experiments was conducted to test the efficiency of different methods of wax removal, and the impact of experimental procedures on cell viability, in order to optimize the method. A strong positive correlation was found between plants&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; ability to retain K(+) in salt-treated leaves and their salinity tolerance, in both wheat and especially barley. The observed effects were related to the ionic but not osmotic component of salt stress. Pharmacological experiments have suggested that voltage-gated K(+) -permeable channels mediate K(+) retention in leaf mesophyll upon elevated NaCl levels in the apoplast. It is concluded that MIFE measurements of NaCl-induced K(+) fluxes from leaf mesophyll may be used as an efficient screening tool for breeding in cereals for salinity tissue tolerance.
A comparative investigation was conducted to evaluate transcriptional changes in guard cells (GCs... more A comparative investigation was conducted to evaluate transcriptional changes in guard cells (GCs) of closely related halophytic (Chenopodium quinoa) and glycophytic (Spinacia oleracea) species. Plants were exposed to 3 weeks of 250 mM sodium chloride treatment, and GC-enriched epidermal fragments were mechanically prepared. In both species, salt-responsive genes were mainly related to categories of protein metabolism, secondary metabolites, signal transduction and transport systems. Genes related to abscisic acid (ABA) signaling and ABA biosynthesis were strongly induced in quinoa but not in spinach GCs. Also, expression of the genes encoding transporters of amino acids, proline, sugars, sucrose and potassium increased in quinoa GCs under salinity stress. Analysis of cell-wall-related genes suggests that genes involved in lignin synthesis (e.g. lignin biosynthesis LACCASE 4) were highly upregulated by salt in spinach GCs. In contrast, transcripts related to cell wall plasticity Pectin methylesterase3 (PME3) were highly induced in quinoa. Faster stomatal response to light and dark measured by observing kinetics of changes in stomatal conductance in quinoa might be associated with higher plasticity of the cell wall regulated by PME3 Furthermore, genes involved in the inhibition of stomatal development and differentiation were highly expressed by salt in quinoa, but not in spinach. These changes correlated with reduced stomatal density and index in quinoa, thus improving its water use efficiency. The fine modulation of transporters, cell wall modification and controlling stomatal development in GCs of quinoa may have resulted in high K+/Na+ ratio, lower stomatal conductance and higher stomatal speed for better adaptation to salinity stress in quinoa.
Background: Waterlogging is one of the main abiotic stresses that limit wheat production. Quantit... more Background: Waterlogging is one of the main abiotic stresses that limit wheat production. Quantitative proteomics analysis has been applied in the study of crop abiotic stress as an effective way in recent years (e.g. salt stress, drought stress, heat stress and waterlogging stress). However, only a few proteins related to primary metabolism and signal transduction, such as UDP-glucose dehydrogenase, UGP, beta glucosidases, were reported to response to waterlogging stress in wheat. The differentially expressed proteins between genotypes of wheat in response to waterlogging are less-defined. In this study, two wheat genotypes, one is sensitive to waterlogging stress (Seri M82, named as S) and the other is tolerant to waterlogging (CIGM90.863, named as T), were compared in seedling roots under hypoxia conditions to evaluate the different responses at proteomic level. Results: A total of 4560 proteins were identified and the number of differentially expressed proteins (DEPs) were 361, 640, 788 in S and 33, 207, 279 in T in 1, 2, 3 days, respectively. These DEPs included 270 common proteins, 681 Sspecific and 50 T-specific proteins, most of which were misc., protein processing, DNA and RNA processing, amino acid metabolism and stress related proteins induced by hypoxia. Some specific proteins related to waterlogging stress, including acid phosphatase, oxidant protective enzyme, S-adenosylmethionine synthetase 1, were significantly different between S and T. A total of 20 representative genes encoding DEPs, including 7 shared DEPs and 13 cultivar-specific DEPs, were selected for further RT-qPCR analysis. Fourteen genes showed consistent dynamic expression patterns at mRNA and protein levels. Conclusions: Proteins involved in primary metabolisms and protein processing were inclined to be affected under hypoxia stress. The negative effects were more severe in the sensitive genotype. The expression patterns of some specific proteins, such as alcohol dehydrogenases and S-adenosylmethionine synthetase 1, could be applied as indexes for improving the waterlogging tolerance in wheat. Some specific proteins identified in this study will facilitate the subsequent protein function validation and biomarker development.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
The disease scald of barley is caused by the pathogen Rhynchosporium commune and can 1 cause up t... more The disease scald of barley is caused by the pathogen Rhynchosporium commune and can 1 cause up to 30-40% yield loss in susceptible varieties. In this study, the Australian barley 1 cultivar Yerong was demonstrated to have resistance that differed from Turk (Rrs1) based on 1 seedling tests with 11 R. commune isolates. A doubled haploid population with 177 lines 2 derived from a cross between Yerong and Franklin was used to identify quantitative trait loci 2 (QTL) for scald resistance. Scald resistance against four pathogen isolates was assessed at the 2 seedling growth stage in a glasshouse experiment and at the adult growth stage in field 2 experiments with natural infection over three consecutive years. A QTL on chromosome 3H 2 was identified with large effect, consistent with a major gene conferring scald resistance at 2 the seedling stage. Under field conditions, scald percentage was negatively correlated with 2 early relative maturity. A bivariate analysis was used to model scald percentage and relative 2 maturity together, residuals from the regression of scald percentage on relative maturity were 2 used as our phenotype for QTL analysis. This analysis identified one major QTL on 2 chromosome 3H, which mapped to the same position as the QTL identified for scald 3 resistance at seedling stage. The identified QTL on 3H is proposed to be different from the 3 Rrs1 on the basis of seedling resistance against different R. commune isolates and physical 3 map position. The analysis also identified an additional novel QTL on chromosome 7H. This 3 study increases the current understanding of scald resistance and identifies genetic material 3 possessing QTLs useful for the marker-assisted selection of scald resistance in barley 3 breeding programs.
Background and Aims Expected increases in world population will continue to make demands on agric... more Background and Aims Expected increases in world population will continue to make demands on agricultural productivity and food supply. These challenges will only be met by increasing the land under cultivation and by improving the yields obtained on existing farms. Genetic engineering can target key traits to improve crop yields and to increase production on marginal soils. Soil acidity is a major abiotic stress that limits plant production worldwide. The goal of this study was to enhance the acid soil tolerance of wheat by increasing its resistance to Al 3+ toxicity. † Methods Particle bombardment was used to transform wheat with TaALMT1, the Al 3+ resistance gene from wheat, using the maize ubiquitin promoter to drive expression. TaALMT1 expression, malate efflux and Al 3+ resistance were measured in the T 1 and T 2 lines and compared with the parental line and an Al 3+-resistant reference genotype, ET8. † Key Results Nine T 2 lines showed increased TaALMT1 expression, malate efflux and Al 3+ resistance when compared with untransformed controls and null segregant lines. Some T 2 lines displayed greater Al 3+ resistance than ET8 in both hydroponic and soil experiments. † Conclusions The Al 3+ resistance of wheat was increased by enhancing TaALMT1 expression with biotechnology. This is the first report of a major food crop being stably transformed for greater Al 3+ resistance. Transgenic strategies provide options for increasing food supply on acid soils.
Lodging in wheat (Triticum aestivum L.) is a complicated phenomenon that is influenced by physiol... more Lodging in wheat (Triticum aestivum L.) is a complicated phenomenon that is influenced by physiological, genetics, and external factors. It causes a great yield loss and reduces grain quality and mechanical harvesting efficiency. Lodging resistance is contributed by various traits, including increased stem strength. The aim of this study was to map quantitative trait loci (QTL) controlling stem strength-related features (the number of big vascular bundles, stem diameter, stem wall thickness) using a doubled haploid (DH) population derived from a cross between Baiqimai and Neixiang 5. Field experiments were conducted during 2020-2022, and glasshouse experiments were conducted during 2021-2022. Significant genetic variations were observed for all measured traits, and they were all highly heritable. Fifteen QTL for stem strength-related traits were identified on chromosomes 2D, 3A, 3B, 3D, 4B, 5A, 6B, 7A, and 7D, respectively, and 7 QTL for grain yield-related traits were identified on chromosomes 2B, 2D, 3D, 4B, 7A, and 7B, respectively. The superior allele of the major QTL for the number of big vascular bundle (VB) was independent of plant height (PH), making it possible to improve stem strength without a trade-off of PH, thus improving lodging resistance. VB also showed positive correlations with some of the yield components. The result will be useful for molecular marker-assisted selection (MAS) for high stem strength and high yield potential.
In-crop soil waterlogging caused by extreme rainfall events, high ground water tables, excessive ... more In-crop soil waterlogging caused by extreme rainfall events, high ground water tables, excessive irrigation and lateral ground water flow inhibit potential grain yields. However, the extent to which yield is influenced by the timing and duration of waterlogging relative to crop phenology is unknown. To investigate this, we conducted various waterlogging treatments on a range of modern barley genotypes varying in their waterlogging tolerance, with tolerance conferred through aerenchyma formation under oxygen deficit conditions. Results showed that yield was reduced by 35% in W1 (waterlogging at Zadoks stage (ZS) 12.5 for one month) to 52% in WL3 (waterlogging at ZS 15 for two months) due to fewer spikes/m2 and kernels/spike. Two weeks waterlogging at ear emergency stage had the greatest impact on yield (70% reduction) due to its effect on spikelet fertility and grain filling. Phenology was delayed 1-8 ZS at the end of waterlogging treatments, with the waterlogging-susceptible cultivar Franklin showing the greatest delays, and waterlogging tolerant genotypes capable of AF (Macquarie+, TAMF169) having the least delays (0-4 ZS). Genotypes with the AF QTL (Macquarie+) showed a slight and nonsignificant yield reduction compared with unwaterlogged controls and mitigated around 23% yield loss under early phenological waterlogging stress.
Extreme weather events threaten food security, yet global assessments of crop waterlogging are ra... more Extreme weather events threaten food security, yet global assessments of crop waterlogging are rare. Here, we make three important contributions to the literature. First, we develop a paradigm that distils common stress patterns across environments, genotypes and climate horizons. Second, we embed improved process-based understanding into a contemporary farming systems model to discern changes in global crop waterlogging under future climates. Third, we elicit viable systems adaptations to waterlogging. Using projections from 27 global circulation models, we show that yield penalties caused by waterlogging increased from 3–11% historically to 10–20% by 2080. Altering sowing time and adopting waterlogging tolerant genotypes reduced yield penalties by up to 18%, while earlier sowing of winter genotypes alleviated waterlogging risk by 8%. We show that future stress patterns caused by waterlogging are likely to be similar to those occurring historically, suggesting that adaptations for ...
Key message Recent developments in understanding the distribution and distinctive features of rec... more Key message Recent developments in understanding the distribution and distinctive features of recombination hotspots are reviewed and approaches are proposed to increase recombination frequency in coldspot regions. Abstract Recombination events during meiosis provide the foundation and premise for creating new varieties of crops. The frequency of recombination in different genomic regions differs across eukaryote species, with recombination generally occurring more frequently at the ends of chromosomes. In most crop species, recombination is rare in centromeric regions. If a desired gene variant is linked in repulsion with an undesired variant of a second gene in a region with a low recombination rate, obtaining a recombinant plant combining two favorable alleles will be challenging. Traditional crop breeding involves combining desirable genes from parental plants into offspring. Therefore, understanding the mechanisms of recombination and factors affecting the occurrence of meiotic recombination is important for crop breeding. Here, we review chromosome recombination types, recombination mechanisms, genes and proteins involved in the meiotic recombination process, recombination hotspots and their regulation systems and discuss how to increase recombination frequency in recombination coldspot regions.
Rice (Oryza sativa) is a staple food that feeds more than half the world population. As rice is h... more Rice (Oryza sativa) is a staple food that feeds more than half the world population. As rice is highly sensitive to soil salinity, current trends in soil salinization threaten global food security. To better understand the mechanistic basis of salinity tolerance in rice, three contrasting rice cultivars-Reiziq (tolerant), Doongara (moderately tolerant), and Koshihikari (sensitive)were examined and the differences in operation of key ion transporters mediating ionic homeostasis in these genotypes were evaluated. Tolerant varieties had reduced Na + translocation from roots to shoots. Electrophysiological and quantitative reverse transcription PCR experiments showed that tolerant genotypes possessed 2-fold higher net Na + efflux capacity in the root elongation zone. Interestingly, this efflux was only partially mediated by the plasma membrane Na + /H + antiporter (OsSOS1), suggesting involvement of some other exclusion mechanisms. No significant difference in Na + exclusion from the mature root zones was found between cultivars, and the transcriptional changes in the salt overly sensitive signaling pathway genes in the elongation zone were not correlated with the genetic variability in salinity tolerance amongst genotypes. The most important hallmark of differential salinity tolerance was in the ability of the plant to retain K + in both root zones. This trait was conferred by at least three complementary mechanisms: (1) its superior ability to activate H +-ATPase pump operation, both at transcriptional and functional levels; (2) reduced sensitivity of K + efflux channels to reactive oxygen species; and (3) smaller upregulation in OsGORK and higher upregulation of OsAKT1 in tolerant cultivars in response to salt stress. These traits should be targeted in breeding programs aimed to improve salinity tolerance in commercial rice cultivars.
Wild rice species provide a rich source of genetic diversity for possible introgression of salini... more Wild rice species provide a rich source of genetic diversity for possible introgression of salinity stress tolerance in cultivated rice. We investigated the physiological basis of salinity stress tolerance in Oryza species by using six rice genotypes (Oryza sativa L.) and four wild rice species. Three weeks of salinity treatment significantly (P < 0.05) reduced physiological and growth indices of all cultivated and wild rice lines. However, the impact of salinity-induced growth reduction differed substantially among accessions. Salt tolerant accessions showed better control over gas exchange properties, exhibited higher tissue tolerance, and retained higher potassium ion content despite higher sodium ion accumulation in leaves. Wild rice species showed relatively lower and steadier xylem sap sodium ion content over the period of 3 weeks analysed, suggesting better control over ionic sodium xylem loading and its delivery to shoots with efficient vacuolar sodium ion sequestration. Contrary to this, saline sensitive genotypes managed to avoid initial Na + loading but failed to accomplish this in the long term and showed higher sap sodium ion content. Conclusively, our results suggest that wild rice genotypes have more efficient control over xylem sodium ion loading, rely on tissue tolerance mechanisms and allow for a rapid osmotic adjustment by using sodium ions as cheap osmoticum for osmoregulation.
Salt stress is an ever-present threat to rice production worldwide. Rice salinity tolerance is co... more Salt stress is an ever-present threat to rice production worldwide. Rice salinity tolerance is complex, both genetically and physiologically. The success and effectiveness in selecting salt-tolerant rice variety require the identification of QTL for the tolerance and closely linked molecular markers. In the present study, a RIL population consisting of 148 lines, derived from a cross between IR29 (salt-sensitive) and Pokkali (salt-tolerant), was used to identify new QTL for salt tolerance and investigate the relationships between salt stress caused injury and the changes in different physiological and morphological traits at the seedling stage. 14,470 high-quality SNP markers generated by the Rice 56K SNP array were converted to 1,467 bin markers for linkage mapping. A high-density genetic linkage map covering 1,680.9 cM was constructed, with the physical to genetic distance ratio being 222 Kb/cM. In total, 23 QTL for different salt tolerance indices were identified, including the previously reported Saltol which is currently used in breeding programmes. Three QTL for salt injury score (SIS) were located on chromosomes 1, 4 and 12, all being closely related to the long-distant Na + transport from roots to shoots. These QTL showed additive effects, thus can be effectively used in breeding programme to pyramid various tolerance genes.
Zinc (Zn) de ciency is a common limiting factor in agricultural soils that signi cantly reduces b... more Zinc (Zn) de ciency is a common limiting factor in agricultural soils that signi cantly reduces both yield and nutritional quality of agricultural produce. Exploring the quantitative trait loci (QTL) for shoot and grain Zn accumulation would help to develop barley cultivars with greater Zn accumulation e ciency. In this study, two glasshouse experiments were conducted by growing plants under adequate and low Zn supply. From the preliminary screening of ten barley cultivars, Sahara (0.05 mg/pot) and Yerong (0.06 mg/pot) showed the lowest difference while Franklin (0.16 mg/pot) had the highest difference in shoot Zn accumulation as a result of the change in Zn supply for plant growth. Therefore, the double haploid (DH) population derived from Yerong x Franklin was selected for the identi cation of QTL for shoot mineral accumulation and biomass production. A major QTL hotspot was detected on chromosome 2H between 31.91-73.12 cM encoding genes for regulating shoot mineral accumulations of Zn, Fe, Ca, K and P, and the biomass. Further investigation demonstrated that 16 potential candidate genes for mineral accumulation, in addition to a single candidate gene for shoot biomass were found in the identi ed QTL region of this study. The genomic region identi ed in this study could be a useful resource for the improvement of mineral nutrient composition and yield potential in future barley breeding programs.
SummaryThe green revolution was based on genetic modification of the gibberellin (GA) hormone sys... more SummaryThe green revolution was based on genetic modification of the gibberellin (GA) hormone system with “dwarfing” gene mutations that reduces GA signals, conferring shorter stature, thus enabling plant adaptation to modern farming conditions. Strong GA‐related mutants with shorter stature often have reduced coleoptile length, discounting yield gain due to their unsatisfactory seedling emergence under drought conditions. Here we present gibberellin (GA) 3‐oxidase1 (GA3ox1) as an alternative semi‐dwarfing gene in barley that combines an optimal reduction in plant height without restricting coleoptile and seedling growth. Using large‐scale field trials with an extensive collection of barley accessions, we showed that a natural GA3ox1 haplotype moderately reduced plant height by 5–10 cm. We used CRISPR/Cas9 technology, generated several novel GA3ox1 mutants and validated the function of GA3ox1. We showed that altered GA3ox1 activities changed the level of active GA isoforms and consequently increased coleoptile length by an average of 8.2 mm, which could provide essential adaptation to maintain yield under climate change. We revealed that CRISPR/Cas9‐induced GA3ox1 mutations increased seed dormancy to an ideal level that could benefit the malting industry. We conclude that selecting HvGA3ox1 alleles offers a new opportunity for developing barley varieties with optimal stature, longer coleoptile and additional agronomic traits.
Background: Aluminium (Al) toxicity is the main factor limiting the crop production in acid soils... more Background: Aluminium (Al) toxicity is the main factor limiting the crop production in acid soils and barley (Hordeum vulgare L.) is one of the most Al-sensitive of the small-grained cereals. The major gene for Al tolerance in barley is HvAACT1 (HvMATE) on chromosome 4H which encodes a multidrug and toxic compound extrusion (MATE) protein. The HvAACT1 protein facilitates the Al-activated release of citrate from root apices which protects the growing cells and enables root elongation to continue. A 1 kb transposable element-like insert in the 5' untranslated region (UTR) of HvAACT1 is associated with increased gene expression and tolerance and a PCR-based marker is available to score for this insertion. Results: We screened a wide range of barley genotypes for Al tolerance and identified a moderately tolerant Chinese genotype named CXHKSL which did not show the typical allele in the 5' UTR of HvAACT1 associated with tolerance. We investigated the mechanism of Al tolerance in CXHKSL and concluded it also relies on the Alactivated release of citrate from roots. Quantitative trait loci (QTL) analysis of double haploid lines generated with CXHKSL and the Al-sensitive variety Gairdner mapped the tolerance locus to the same region as HvAACT1 on chromosome 4H. Conclusions: Our results show that the Chinese barley genotype CXHKSL possesses a novel allele of the major Al tolerance gene HvAACT1.
Key message This study demonstrates how identification of genes underpinning disease-resistance Q... more Key message This study demonstrates how identification of genes underpinning disease-resistance QTL based on differential expression and SNPs can be improved by performing transcriptomic analysis on multiple near isogenic lines. Abstract Transcriptomic analysis has been widely used to understand the genetic basis of a trait of interest by comparing genotypes with contrasting phenotypes. However, these approaches identify such large sets of differentially expressed genes that it proves difficult to isolate which genes underpin the phenotype of interest. This study tests whether using multiple near isogenic lines (NILs) can improve the resolution of RNA-seq-based approaches to identify genes underpinning diseaseresistance QTL. A set of NILs for a major effect Fusarium crown rot-resistance QTL in barley on the 4HL chromosome arm were analysed under Fusarium crown rot using RNA-seq. Differential gene expression and single nucleotide polymorphism detection analyses reduced the number of putative candidates from thousands within individual NIL pairs to only one hundred and two genes, which were differentially expressed or contained SNPs in common across NIL pairs and occurred on 4HL. Our findings support the value of performing RNA-seq analysis using multiple NILs to remove genetic background effects. The enrichment analyses indicated conserved differences in the response to infection between resistant and sensitive isolines suggesting that sensitive isolines are impaired in systemic defence response to Fusarium pseudograminearum.
Models are key tools in our quest to better understand the impacts of soil waterlogging on plant ... more Models are key tools in our quest to better understand the impacts of soil waterlogging on plant growth and crop production. Here, we reviewed the state of the art of modeling approaches and compared the conceptual design of these models with recent experimental findings. We show that many models adopt an aeration stress (AS) principle where surplus water reduces air-filled porosity, with implications for root growth. However, subsequent effects of AS within each model vary considerably. In some cases, AS inhibits biomass accumulation (e.g. AquaCrop), altering processes prior to biomass accumulation such as light interception (e.g. APSIM), or photosynthesis and carbohydrate accumulation (e.g. SWAGMAN Destiny). While many models account for stage-dependent waterlogging effects, few models account for experimentally observed delays in phenology caused by waterlogging. A model intercomparison specifically designed for long-term waterlogged conditions (APSIM-Oryza) with models developed for dryland conditions with transient waterlogging would advance our understanding of the current fitness for purpose of exsiting frameworks for simulating transient waterlogging in dryland cropping systems. Of the point-based dynamic models examined here, APSIM-Soybean and APSIM-Oryza simulations most closely matched with the observed data, while GLAM-WOFOST achieved the highest performance of the spatial-regional models examined. We conclude that future models should incorporate waterlogging effects on genetic tolerance parameters such as (1) phenology of stress onset, (2) aerenchyma, (3) root hydraulic conductance, (4) nutrient-use efficiency, and (5) plant ion (e.g. Fe/Mn) tolerance. Incorporating these traits/effects into models, together with a more systematic model intercomparison using consistent initialization data, will significantly improve our understanding of the relative importance of such factors in a systems context, including feedbacks between biological factors, emergent properties, and sensitive variables responsible for yield losses under waterlogging.
Salinity tolerance is a complex traitboth physiologically and geneticallyand the issue of which m... more Salinity tolerance is a complex traitboth physiologically and geneticallyand the issue of which mechanism or trait has bigger contribution towards the overall plant performance is still hotly discussed in the literature. In this work, a broad range of barley (Hordeum vulgare L. and Hordeum spontaneum L.) genotypes contrasting in salinity stress tolerance were used to investigate the causal link between plant stomatal characteristics, tissue ion relations, and salinity tolerance. In total, 46 genotypes (including two wild barleys) were grown under glasshouse conditions and exposed to moderate salinity stress (200 mM NaCl) for 5 weeks. The overall salinity tolerance correlated positively with stomata density, leaf K + concentration and the relative contribution of inorganic ions towards osmotic adjustment in the shoot. At the same time, no correlation between salinity tolerance and stomatal conductance or leaf Na + content in the shoot was found. Taken together, these results indicate the importance of increasing stomata density as an adaptive tool to optimise efficiency of CO 2 assimilation under moderate saline conditions, as well as benefits of the predominant use of inorganic osmolytes for osmotic adjustment in barley. Another finding of note was that wild barleys showed rather different strategies dealing with salinity, as compared with cultivated varieties.
This work investigated the importance of the ability of leaf mesophyll cells to control K(+) flux... more This work investigated the importance of the ability of leaf mesophyll cells to control K(+) flux across the plasma membrane as a trait conferring tissue tolerance mechanism in plants grown under saline conditions. Four wheat (Triticum aestivum and Triticum turgidum) and four barley (Hordeum vulgare) genotypes contrasting in their salinity tolerance were grown under glasshouse conditions. Seven to 10-day-old leaves were excised, and net K(+) and H(+) fluxes were measured from either epidermal or mesophyll cells upon acute 100 mM treatment (mimicking plant failure to restrict Na(+) delivery to the shoot) using non-invasive microelectrode ion flux estimation (the MIFE) system. To enable net ion flux measurements from leaf epidermal cells, removal of epicuticular waxes was trialed with organic solvents. A series of methodological experiments was conducted to test the efficiency of different methods of wax removal, and the impact of experimental procedures on cell viability, in order to optimize the method. A strong positive correlation was found between plants&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; ability to retain K(+) in salt-treated leaves and their salinity tolerance, in both wheat and especially barley. The observed effects were related to the ionic but not osmotic component of salt stress. Pharmacological experiments have suggested that voltage-gated K(+) -permeable channels mediate K(+) retention in leaf mesophyll upon elevated NaCl levels in the apoplast. It is concluded that MIFE measurements of NaCl-induced K(+) fluxes from leaf mesophyll may be used as an efficient screening tool for breeding in cereals for salinity tissue tolerance.
A comparative investigation was conducted to evaluate transcriptional changes in guard cells (GCs... more A comparative investigation was conducted to evaluate transcriptional changes in guard cells (GCs) of closely related halophytic (Chenopodium quinoa) and glycophytic (Spinacia oleracea) species. Plants were exposed to 3 weeks of 250 mM sodium chloride treatment, and GC-enriched epidermal fragments were mechanically prepared. In both species, salt-responsive genes were mainly related to categories of protein metabolism, secondary metabolites, signal transduction and transport systems. Genes related to abscisic acid (ABA) signaling and ABA biosynthesis were strongly induced in quinoa but not in spinach GCs. Also, expression of the genes encoding transporters of amino acids, proline, sugars, sucrose and potassium increased in quinoa GCs under salinity stress. Analysis of cell-wall-related genes suggests that genes involved in lignin synthesis (e.g. lignin biosynthesis LACCASE 4) were highly upregulated by salt in spinach GCs. In contrast, transcripts related to cell wall plasticity Pectin methylesterase3 (PME3) were highly induced in quinoa. Faster stomatal response to light and dark measured by observing kinetics of changes in stomatal conductance in quinoa might be associated with higher plasticity of the cell wall regulated by PME3 Furthermore, genes involved in the inhibition of stomatal development and differentiation were highly expressed by salt in quinoa, but not in spinach. These changes correlated with reduced stomatal density and index in quinoa, thus improving its water use efficiency. The fine modulation of transporters, cell wall modification and controlling stomatal development in GCs of quinoa may have resulted in high K+/Na+ ratio, lower stomatal conductance and higher stomatal speed for better adaptation to salinity stress in quinoa.
Background: Waterlogging is one of the main abiotic stresses that limit wheat production. Quantit... more Background: Waterlogging is one of the main abiotic stresses that limit wheat production. Quantitative proteomics analysis has been applied in the study of crop abiotic stress as an effective way in recent years (e.g. salt stress, drought stress, heat stress and waterlogging stress). However, only a few proteins related to primary metabolism and signal transduction, such as UDP-glucose dehydrogenase, UGP, beta glucosidases, were reported to response to waterlogging stress in wheat. The differentially expressed proteins between genotypes of wheat in response to waterlogging are less-defined. In this study, two wheat genotypes, one is sensitive to waterlogging stress (Seri M82, named as S) and the other is tolerant to waterlogging (CIGM90.863, named as T), were compared in seedling roots under hypoxia conditions to evaluate the different responses at proteomic level. Results: A total of 4560 proteins were identified and the number of differentially expressed proteins (DEPs) were 361, 640, 788 in S and 33, 207, 279 in T in 1, 2, 3 days, respectively. These DEPs included 270 common proteins, 681 Sspecific and 50 T-specific proteins, most of which were misc., protein processing, DNA and RNA processing, amino acid metabolism and stress related proteins induced by hypoxia. Some specific proteins related to waterlogging stress, including acid phosphatase, oxidant protective enzyme, S-adenosylmethionine synthetase 1, were significantly different between S and T. A total of 20 representative genes encoding DEPs, including 7 shared DEPs and 13 cultivar-specific DEPs, were selected for further RT-qPCR analysis. Fourteen genes showed consistent dynamic expression patterns at mRNA and protein levels. Conclusions: Proteins involved in primary metabolisms and protein processing were inclined to be affected under hypoxia stress. The negative effects were more severe in the sensitive genotype. The expression patterns of some specific proteins, such as alcohol dehydrogenases and S-adenosylmethionine synthetase 1, could be applied as indexes for improving the waterlogging tolerance in wheat. Some specific proteins identified in this study will facilitate the subsequent protein function validation and biomarker development.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
The disease scald of barley is caused by the pathogen Rhynchosporium commune and can 1 cause up t... more The disease scald of barley is caused by the pathogen Rhynchosporium commune and can 1 cause up to 30-40% yield loss in susceptible varieties. In this study, the Australian barley 1 cultivar Yerong was demonstrated to have resistance that differed from Turk (Rrs1) based on 1 seedling tests with 11 R. commune isolates. A doubled haploid population with 177 lines 2 derived from a cross between Yerong and Franklin was used to identify quantitative trait loci 2 (QTL) for scald resistance. Scald resistance against four pathogen isolates was assessed at the 2 seedling growth stage in a glasshouse experiment and at the adult growth stage in field 2 experiments with natural infection over three consecutive years. A QTL on chromosome 3H 2 was identified with large effect, consistent with a major gene conferring scald resistance at 2 the seedling stage. Under field conditions, scald percentage was negatively correlated with 2 early relative maturity. A bivariate analysis was used to model scald percentage and relative 2 maturity together, residuals from the regression of scald percentage on relative maturity were 2 used as our phenotype for QTL analysis. This analysis identified one major QTL on 2 chromosome 3H, which mapped to the same position as the QTL identified for scald 3 resistance at seedling stage. The identified QTL on 3H is proposed to be different from the 3 Rrs1 on the basis of seedling resistance against different R. commune isolates and physical 3 map position. The analysis also identified an additional novel QTL on chromosome 7H. This 3 study increases the current understanding of scald resistance and identifies genetic material 3 possessing QTLs useful for the marker-assisted selection of scald resistance in barley 3 breeding programs.
Background and Aims Expected increases in world population will continue to make demands on agric... more Background and Aims Expected increases in world population will continue to make demands on agricultural productivity and food supply. These challenges will only be met by increasing the land under cultivation and by improving the yields obtained on existing farms. Genetic engineering can target key traits to improve crop yields and to increase production on marginal soils. Soil acidity is a major abiotic stress that limits plant production worldwide. The goal of this study was to enhance the acid soil tolerance of wheat by increasing its resistance to Al 3+ toxicity. † Methods Particle bombardment was used to transform wheat with TaALMT1, the Al 3+ resistance gene from wheat, using the maize ubiquitin promoter to drive expression. TaALMT1 expression, malate efflux and Al 3+ resistance were measured in the T 1 and T 2 lines and compared with the parental line and an Al 3+-resistant reference genotype, ET8. † Key Results Nine T 2 lines showed increased TaALMT1 expression, malate efflux and Al 3+ resistance when compared with untransformed controls and null segregant lines. Some T 2 lines displayed greater Al 3+ resistance than ET8 in both hydroponic and soil experiments. † Conclusions The Al 3+ resistance of wheat was increased by enhancing TaALMT1 expression with biotechnology. This is the first report of a major food crop being stably transformed for greater Al 3+ resistance. Transgenic strategies provide options for increasing food supply on acid soils.
Lodging in wheat (Triticum aestivum L.) is a complicated phenomenon that is influenced by physiol... more Lodging in wheat (Triticum aestivum L.) is a complicated phenomenon that is influenced by physiological, genetics, and external factors. It causes a great yield loss and reduces grain quality and mechanical harvesting efficiency. Lodging resistance is contributed by various traits, including increased stem strength. The aim of this study was to map quantitative trait loci (QTL) controlling stem strength-related features (the number of big vascular bundles, stem diameter, stem wall thickness) using a doubled haploid (DH) population derived from a cross between Baiqimai and Neixiang 5. Field experiments were conducted during 2020-2022, and glasshouse experiments were conducted during 2021-2022. Significant genetic variations were observed for all measured traits, and they were all highly heritable. Fifteen QTL for stem strength-related traits were identified on chromosomes 2D, 3A, 3B, 3D, 4B, 5A, 6B, 7A, and 7D, respectively, and 7 QTL for grain yield-related traits were identified on chromosomes 2B, 2D, 3D, 4B, 7A, and 7B, respectively. The superior allele of the major QTL for the number of big vascular bundle (VB) was independent of plant height (PH), making it possible to improve stem strength without a trade-off of PH, thus improving lodging resistance. VB also showed positive correlations with some of the yield components. The result will be useful for molecular marker-assisted selection (MAS) for high stem strength and high yield potential.
In-crop soil waterlogging caused by extreme rainfall events, high ground water tables, excessive ... more In-crop soil waterlogging caused by extreme rainfall events, high ground water tables, excessive irrigation and lateral ground water flow inhibit potential grain yields. However, the extent to which yield is influenced by the timing and duration of waterlogging relative to crop phenology is unknown. To investigate this, we conducted various waterlogging treatments on a range of modern barley genotypes varying in their waterlogging tolerance, with tolerance conferred through aerenchyma formation under oxygen deficit conditions. Results showed that yield was reduced by 35% in W1 (waterlogging at Zadoks stage (ZS) 12.5 for one month) to 52% in WL3 (waterlogging at ZS 15 for two months) due to fewer spikes/m2 and kernels/spike. Two weeks waterlogging at ear emergency stage had the greatest impact on yield (70% reduction) due to its effect on spikelet fertility and grain filling. Phenology was delayed 1-8 ZS at the end of waterlogging treatments, with the waterlogging-susceptible cultivar Franklin showing the greatest delays, and waterlogging tolerant genotypes capable of AF (Macquarie+, TAMF169) having the least delays (0-4 ZS). Genotypes with the AF QTL (Macquarie+) showed a slight and nonsignificant yield reduction compared with unwaterlogged controls and mitigated around 23% yield loss under early phenological waterlogging stress.
Extreme weather events threaten food security, yet global assessments of crop waterlogging are ra... more Extreme weather events threaten food security, yet global assessments of crop waterlogging are rare. Here, we make three important contributions to the literature. First, we develop a paradigm that distils common stress patterns across environments, genotypes and climate horizons. Second, we embed improved process-based understanding into a contemporary farming systems model to discern changes in global crop waterlogging under future climates. Third, we elicit viable systems adaptations to waterlogging. Using projections from 27 global circulation models, we show that yield penalties caused by waterlogging increased from 3–11% historically to 10–20% by 2080. Altering sowing time and adopting waterlogging tolerant genotypes reduced yield penalties by up to 18%, while earlier sowing of winter genotypes alleviated waterlogging risk by 8%. We show that future stress patterns caused by waterlogging are likely to be similar to those occurring historically, suggesting that adaptations for ...
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