Yield Penalty Research Articles

Releasing a sugar brake generates sweeter tomato without yield penalty

In tomato, sugar content is highly correlated with consumer preferences, with most consumers preferring sweeter fruit1–4. However, the sugar content of commercial varieties is generally low, as it is inversely correlated with fruit size, and growers prioritize yield over flavour quality5–7. Here we identified two genes, tomato (Solanum lycopersicum) calcium-dependent protein kinase 27 (SlCDPK27; also known as SlCPK27) and its paralogue SlCDPK26, that control fruit sugar content. They act as sugar brakes by phosphorylating a sucrose synthase, which promotes degradation of the sucrose synthase. Gene-edited SlCDPK27 and SlCDPK26 knockouts increased glucose and fructose contents by up to 30%, enhancing perceived sweetness without fruit weight or yield penalty. Although there are fewer, lighter seeds in the mutants, they exhibit normal germination. Together, these findings provide insight into the regulatory mechanisms controlling fruit sugar accumulation in tomato and offer opportunities to increase sugar content in large-fruited cultivars without sacrificing size and yield.

Dryland pea seeding rates can be reduced without yield or economic penalty

AbstractMontana is the leading producer of field peas (Pisum sativum L.) in the United States. A density of 8 to 10 plants ft−2 is recommended when growing field peas in that state, but this recommendation is based on work done elsewhere. Field experiments were conducted in central Montana from 2021 through 2023 and at three additional locations in the final year to determine the yield and the economically optimum plant population (EOPP) when growing field peas for grain. The semi‐leafless, yellow‐cotyledon variety Montech 4152 was planted at five rates (5, 7, 9, 11, and 13 pure live seed [PLS] ft−2) in all 3 years with two additional rates (3 and 15 PLS ft−2) added in the final year. A minimum plant density of 6 to 8 plants ft−2, or planting field pea at 7 to 9 PLS ft−2, produced a grain yield comparable to or greater than amounts produced at other seeding rates. The minimum EOPP across the six experiments ranged from 3 (2.8) to 7 (6.4) plants ft−2, corresponding to a seeding rate of 3 to 7 PLS ft−2. However, more weeds were observed when field pea was planted at 3 PLS ft−2 than at higher rates in one of the experiments. A field pea density of 6 to 8 plants ft−2 is sufficient to optimize grain yield and economic returns in Montana and similar dryland environments.

Yield more in the shadow: Mitigating shading-induced yield penalty of maize via optimizing source-sink carbon partitioning

Global solar radiation has been decreasing, posing a great threat to food security by reducing photo-assimilation and disrupting carbon (C) partitioning in crops like maize. However, practical countermeasures to cope with source-sink balance in periodic shading stress are lacking. Here, we first simulated shading stresses with different degrees and occurring periods on field maize for two years. Results verified that shading-induced yield penalties are most severe around silking and are closely associated with biomass allocation, implying a significant imbalance of source: sink C partitioning during silking. To mitigate yield losses from shading, detasseling (Det) and synchronous pollination (SP), targeting the two sink tissues (tassel and ear, respectively), were applied to 70 % shading at the silking stage in two seasons. Both practices conferred benefits to grain number and yield production, with final yield increases ranging from 4.0 % to 31.3 % under shading. Through 13C labeling, sugar metabolism assay and global analysis, we proved that Det improved the source-sink balance via increasing light irradiance within the canopy and eliminating apical dominance to stimulate C assimilates partitioning into the ear. SP promoted C partitioning into the ear by increasing reproductive sink strength and optimizing assimilates allocation among grain siblings. Intriguingly, Det and SP also provided marginal yield increase under normal light conditions. Our findings underscore the potential of source-sink coordination and C partitioning in mitigating maize yield penalty under environmental stresses like shading. The research also provides new avenues for developing agronomic practices and breeding strategies via tasseling and silking regulation, aiming to improve maize crop production and stress resilience and ensure food security in the face of climate change.

CRISPR/Cas9-mediated OsFd1 editing enhances rice broad-spectrum resistance without growth and yield penalty.

CRISPR/Cas9-mediated OsFd1 editing enhances rice broad-spectrum resistance without growth and yield penalty.

Overexpression of tae-miR9670 enhances cadmium tolerance in wheat by targeting mTERFs without yield penalty

Cadmium (Cd) is a widely distributed heavy metal that poses significant hazards to both crop productivity and human health. MicroRNAs (miRNAs) play pivotal roles in plant growth, development and responses to environmental stresses, yet little is known about their roles in regulating Cd tolerance in wheat. In this study, we identified tae-miR9670, a Triticeae-specific miRNA, as responsive to Cd exposure in wheat through miRNAome analysis. Tae-miR9670 can target genes that encode mitochondrial transcription termination factors (mTERFs), mediating their mRNA cleavage and suppressing their expression. Overexpression of tae-miR9670 significantly enhanced Cd tolerance in wheat seedlings, as demonstrated by increased biomass and reduced levels of malondialdehyde (MDA), H2O2, and Cd content. Consequently, multiple downstream genes involved in ROS scavenging, detoxification and heavy metal transport were upregulated in tae-miR9670 overexpression plants. Moreover, the grain Cd content in mature plants overexpressing tae-miR9670 was reduced by over 60 % compared to wild-type controls. Our results also indicated that overexpressing tae-miR9670 in wheat preserved yield-related traits, thereby overcoming the trade-off between stress resistance and grain yield. Overall, our findings provide new insights into the role of tae-miR9670 in Cd tolerance in wheat and its potential application in breeding low-Cd cultivars.

Integrative Proteomic and Phosphoproteomic Profiling Reveals the Salt-Responsive Mechanisms in Two Rice Varieties (Oryza Sativa subsp. Japonica and Indica).

Salinity stress induces ionic and osmotic imbalances in rice plants that in turn negatively affect the photosynthesis rate, resulting in growth retardation and yield penalty. Efforts have, therefore, been carried out to understand the mechanism of salt tolerance, however, the complexity of biological processes at proteome levels remains a major challenge. Here, we performed a comparative proteome and phosphoproteome profiling of microsome enriched fractions of salt-tolerant (cv. IR73; indica) and salt-susceptible (cv. Dongjin/DJ; japonica) rice varieties. This approach led to the identification of 5856 proteins, of which 473 and 484 proteins showed differential modulation between DJ and IR73 sample sets, respectively. The phosphoproteome analysis led to the identification of a total of 10,873 phosphopeptides of which 2929 and 3049 phosphopeptides showed significant differences in DJ and IR73 sample sets, respectively. The integration of proteome and phosphoproteome data showed activation of ABA and Ca2+ signaling components exclusively in the salt-tolerant variety IR73 in response to salinity stress. Taken together, our results highlight the changes at proteome and phosphoproteome levels and provide a mechanistic understanding of salinity stress tolerance in rice.

Volatilome-based GWAS identifies OsWRKY19 and OsNAC021 as key regulators of rice aroma

Aromatic rice is globally favored for its distinctive scent, not only increasing nutritional value but also enhancing economic importance. However, apart from 2-acetyl-1-pyrroline (2-AP), the metabolic basis of aroma remains elusive, and the genetic underlying of the accumulation of fragrance metabolites are largely unknown. Here, we revealed 2-AP and fatty acid-derived volatile metabolites (FAVs) as key contributors to rice aroma by combining aroma rating with molecular docking. Using volatilome-based GWAS, we identified two regulatory genes that determine the natural variation of these fragrance metabolites. We demonstrated that OsWRKY19 not only enhances fragrance by negatively regulating OsBADH2 but also promotes agricultural traits in rice. Additionally, we revealed OsNAC021 that negatively regulates FAVs through the LOX pathway, and the knockout of it resulted in the over-accumulation of grain FAVs without a yield penalty. Our findings provide a compelling example of deciphering the genetic regulatory mechanisms underlying rice fragrance and pave the way for the creation of aromatic rice varieties.

Genetic Diversity of Maize (Zea mays L.) Genotypes under Low Level of Nitrogen

Maize (Zea mays L.) is India's second most significant crop, behind rice. As a cross-pollinated crop, hybrid vigour is commonly used to achieve the best production potential. The selection of various genotypes is a primary goal in the maize hybrid breeding programme. Maize is a voracious feeder and requires a lot of fertiliser. The biggest limits on maize production in India are low soil nitrogen and high fertiliser costs. Jharkhand consumes only 82.5 kg of total fertiliser nutrients per acre. In order to discover genetically varied maize genotypes for nitrogen usage efficiency, the current study evaluated 121 maize genotypes in a randomised block design with two replications at low nitrogen levels. Plant height, days to 50% pollen shed, days to 50% silk, anthesis-silking interval (ASI), days to75% maturity, number of leaves per plant, root length, stover yield per plant, grain yield per plant, and harvest index were all recorded. Statistical analysis was performed using the morphological trait data. Analysis of variance revealed substantial (p≤0.05) variations in morphological features between maize genotypes. For statistical analysis, a clustering method was used to locate various genotypes with greater genetic distance in order to develop good heterotic combinations. One hundred twenty one genotypes were divided into six clusters using the dendogram-by-ward minimum variance approach. Cluster III and V had the greatest inter-cluster distance (79.26), followed by cluster III and VI (74.77) and cluster II and III (73.80). The many heterotic combinations developed from these clusters can be employed in subsequent breeding programmes to produce low nitrogen-requiring hybrids with a low yield penalty.

Yr29 combined with QYr.nwafu-4BL.3 confers durable resistance to stripe rust in wheat cultivar Jing 411.

The combination of a QTL on chromosome arm 4BL and Yr29 provides durable resistance with no significant yield penalty. Wheat stripe rust or yellow rust (YR), caused by Puccinia striiformis f. sp. tritici (Pst), causes substantial yield reductions globally, but losses can be minimized by using resistance genes. Chinese wheat cultivar Jing 411 (J411) has continued to display an acceptable level of adult-plant resistance (APR) to YR in varied field conditions since its release in the 1990s. A recombinant inbred line (RIL) population comprising 187 lines developed from a cross of J411 and Kenong 9204 (KN9204) was evaluated in multiple environments to identify genomic regions carrying genes for YR resistance. A total of five quantitative trait loci (QTL) on chromosome arm 1BL, 3BS, 4BL, 6BS, and 7BL from J411 and two QTL on 3DS and 7DL from KN9204 were detected using inclusive composite interval mapping with the wheat 660K SNP array. QYr.nwafu-1BL.5 and QYr.nwafu-4BL.3 from J411 were robust and showed similar effects in all environments. QYr.nwafu-1BL.5 was likely the pleiotropic gene of Yr29/Lr46. QYr.nwafu-4BL.3 was located within a 1.0cM interval delimited by KASP markers AX-111609222 and AX-89755491. Based on haplotype analysis, Yr29 and QYr.nwafu-4BL.3 were identified as genetic components of quantitative resistance in a number of wheat cultivars. Moreover, RILs with Yr29 and QYr.nwafu-4BL.3 individually or when combined showed higher resistance to YR in rust nurseries compared with RILs without them, and there was no negative effect of their presence on agronomic traits under rust-free conditions. These results suggest that effective polymerization strategy is important for breeding high yielding and durable resistance cultivars.

Engineered reduction of S-adenosylmethionine alters lignin in sorghum

BackgroundLignin is an aromatic polymer deposited in secondary cell walls of higher plants to provide strength, rigidity, and hydrophobicity to vascular tissues. Due to its interconnections with cell wall polysaccharides, lignin plays important roles during plant growth and defense, but also has a negative impact on industrial processes aimed at obtaining monosaccharides from plant biomass. Engineering lignin offers a solution to this issue. For example, previous work showed that heterologous expression of a coliphage S-adenosylmethionine hydrolase (AdoMetase) was an effective approach to reduce lignin in the model plant Arabidopsis. The efficacy of this engineering strategy remains to be evaluated in bioenergy crops.ResultsWe studied the impact of expressing AdoMetase on lignin synthesis in sorghum (Sorghum bicolor L. Moench). Lignin content, monomer composition, and size, as well as biomass saccharification efficiency were determined in transgenic sorghum lines. The transcriptome and metabolome were analyzed in stems at three developmental stages. Plant growth and biomass composition was further evaluated under field conditions. Results evidenced that lignin was reduced by 18% in the best transgenic line, presumably due to reduced activity of the S-adenosylmethionine-dependent O-methyltransferases involved in lignin synthesis. The modified sorghum features altered lignin monomer composition and increased lignin molecular weights. The degree of methylation of glucuronic acid on xylan was reduced. These changes enabled a ~20% increase in glucose yield after biomass pretreatment and saccharification compared to wild type. RNA-seq and untargeted metabolomic analyses evidenced some pleiotropic effects associated with AdoMetase expression. The transgenic sorghum showed developmental delay and reduced biomass yields at harvest, especially under field growing conditions.ConclusionsThe expression of AdoMetase represents an effective lignin engineering approach in sorghum. However, considering that this strategy potentially impacts multiple S-adenosylmethionine-dependent methyltransferases, adequate promoters for fine-tuning AdoMetase expression will be needed to mitigate yield penalty.

Reducing initial cotton yield penalties in a transition to conservation agriculture through legume cover crop cultivation – evidence from Northern Benin

Much effort has been spent on promoting conservation agriculture (CA) in Northern Benin to sustain the transition of cotton (Gossypium hirsutum L.) cropping systems toward agroecology. However, its limited adoption by farmers is often ascribed to initial yield penalties during the transition to CA and to trade-offs around crop biomass use. Here, we assess the effect of different CA-based cropping systems promoted in the region on water productivity and cotton yield in a three-year cotton/maize (Zea mays L.) crop rotation during the initial transition phase to CA. Three CA options were assessed combining different levels of soil disturbance and cover, and introducing cover crops to alleviate the biomass trade-offs. Direct seeding (DS), strip tillage (ST), and direct seeding mulched-based cropping systems (DMC) were compared with conventional tillage (CT) from 2017 to 2019 under a dominant soil type in the region, Haplic Lixisols. Two legume species, Stylosanthes guianensis (Aubl.) Sw. and Crotalaria retusa L. were grown as cover crops with maize under ST and DMC. The experiment followed a randomized block design comprising six replicates. After 2–3 years of DMC, the cotton yield advantage with respect to CT increased from 5 % to 7 %. Cotton yield penalties of respectively 11 % in 2018 and 26 % in 2019 were found for DS. ST treatment went from a yield advantage of 8 % in 2017 to a yield penalty of 20 % in 2019. The DMC and CT treatments gave similar and highest boll weights compared to the ST and DS treatments. The treatments had no significant difference regarding the number of bolls per plant. Soil water storage in the upper 30 cm depth and water use efficiency (WUE) were the highest in the plots with the DMC treatment compared to CT, ST, and DS. At 28 days of active vegetative stage (between 34 and 62 days after sowing), the WUE of seed cotton was 0.11 kg ha−1 mm−1 under DMC, while it was 0.08, 0.07, and 0.04 kg ha−1 mm−1 under DS, CT, and ST, respectively. The performance of DMC at increasing water productivity could be an argument to improve adoptability by farmers in northern Benin who are facing increased weather variability, given that the yield penalties often associated with early transitions to CA were not observed here with full DMC.

Quantifying the contribution of individual inputs used in Zero Budget Natural Farming

AbstractZero Budget Natural Farming (ZBNF) in Andhra Pradesh promotes home‐made, locally sourced, agrochemical‐free inputs and regenerative land management techniques. Inputs consist of seed treatments (bijamrita), microbial inoculum applied either as a liquid foliar spray (liquid jiwamrita) or solid top dressing (solid jiwamrita) to the soil, and mulching (achhadana). However, some farmers do not use all the recommended inputs. There is a lack of evidence on the effects of partial adoption on the resulting yield and on the contributions of individual inputs to the performance of the overall approach. Controlled field experiments were established over two seasons across four agro‐climatic zones. They consisted of five treatments. A Standard ZBNF treatment, which included application of all four ZBNF amendments (bijamirita, solid jiwamrita, liquid jiwamrita and dead mulch). The subsequent four treatments excluded one of the ZBNF inputs (Minus Bijamrita, Minus Soilid Jiwamrita, Minus Liquid Jiwamrita, and Minus Dead Mulch). Exclusion of each ZBNF input individually resulted in a significantly smaller yield than the treatment where all four inputs were used. However, exclusion of solid jiwamrita, liquid jiwamrita and mulching had a larger yield penalty than exclusion of bijamrita. Partial adoption could therfore impact the efficacy of the ZBNF system to deliver sustainable crop yields and satisfy food security. However, further research is needed to examine the effects of input exclusion in the long term, and possible interactions between different ZBNF inputs.

Response of wheat to arbuscular mycorrhizal fungi inoculation and biochar application: Implications for soil carbon sequestration

The sequestration of atmospheric CO₂ in soil is suggested as an effective climate change mitigation strategy. Biochar application shows promise in this regard, while the role of fungi in soil carbon cycling and sequestration is also under investigation. Using a novel high-throughput plant phenomics approach, we explore the impact of arbuscular mycorrhizal fungi (AMF) inoculation and biochar application on wheat growth and soil carbon, guided by one of the leading global carbon credit schemes. Wheat was successfully colonised by AMF, achieving an average root length colonisation of 35.9%. We uncover an indirect fungal-mediated pathway to soil carbon sequestration, with mycorrhizal plants generating more biomass across all soil treatments without yield penalties, suggesting colonised plants deliver more plant derived carbon to the soil, potentially leading to long-term soil carbon gains. Conversely, fungal-driven carbon loss occurred, significantly reducing soil carbon accumulation in unamended soil, but not in biochar-amended soil, suggesting that biochar moderates fungal activity and positively impacts the soil carbon balance. While both biochar and AMF enhance plant growth, their direct effects on soil carbon are complex. Although biochar did not significantly increase soil carbon stocks beyond its own contribution, its ability to regulate fungal activity could play an important role in influencing soil carbon sequestration.

Evaluation of rabi season sesame productivity from graded nutrient doses and tillage regimes in rice fallows of southern plateau and hills region of the Indian sub-continent.

Only scattered information is available on the tillage and nutrient management information for the sesame crop following rice in the literature. Sesame as an edible oil yielding crop with high levels of unsaturated fatty acids has high international demand due to superior health benefits. Being a small seeded crop, it requires standard tillage and nutrient management to obtain optimum productivity under rice fallow ecologies. As a sequential crop after rice harvest, the tillage and nutrient management practices followed for the preceding rice have astounding effects on the succeeding sesame crop. To better understand and manipulate the agro ecology in the rice fallow culture, it is necessary to study the behaviour of sesame cultivars, in relation to the tillage requirements and macro nutrient factors that have a bearing on the productivity. The aim of this work was to evaluate the productivity of rice fallow sesame in the southern plateau and hills regions of the Indian sub-continent (Tamil Nadu) with a hypothesis that tillage and nutrient management would immensely benefit the sesame crop. Field experiments were conducted at TNAU, Tamil Nadu Rice Research Institute, Aduturai, Tamil Nadu during 2019-2020 and 2020-2021 with tillage practices (reduced tillage, conventional tillage and zero tillage) and fertilizer doses (zero percent RDF, 25% RDF, 50% RDF, 75% RDF and 100% RDF) in a split plot design replicated thrice. The results have clearly indicated that the performance of rice fallow sesame was poor under zero till conditions as the sesame crop is poorly adapted leading to a yield penalty up to 68%. A total of 75% RDF has yielded statistically similar yield to that of 100% RDF to the rice fallow sesame. Further, neither the oil content nor the fatty acid composition was modified by tillage and nutrient management regimes.

Organic waste recycling application increases N availability and mitigates N2O emission without crop yield penalty in the North China Plain.

Agricultural organic waste recycling can supply nutrients for crop production and partially replace chemical nitrogen fertilizers, which is beneficial for waste management and environmental protection. Nevertheless, comprehensive evaluation of the effects of different organic materials applications on crop yield and the environment is limited. Therefore, in this study, a comprehensive investigation of the synergistic effects of straw, pig manure, and biogas residue recycling on the wheat (Triticum aestivum L.) and maize (Zea mays L.) systems was carried out in the North China Plain. Field experiments were conducted from 2019 to 2021, comprising five treatments: straw (ST), pig manure (PM), and biogas residue (BR) partially replacing chemical nitrogen fertilizer, sole application of chemical nitrogen fertilizer (CF), and a control with no nitrogen application (WN). The results showed that organic materials significantly increased soil total nitrogen (3.04%-9.10%) and N recovery efficiency (REN; 42.21%-44.99%), but pig manure was more beneficial in increasing crop yields (3.50%), especially wheat yields (8.72%), and REN was significantly higher than that of the other treatments. Organic materials performed differently in wheat and maize seasons, and wheat yield could be improved by organic materials return. Organic materials stimulated N2O emission in wheat season (4.28%-32.20%), while biogas residue inhibited the N2O emission in maize season (47.47%). The negative effect of straw and biogas residue on yield decreased with increasing years of return, and pig manure continued to contribute to yield. In conclusion, pig manure is the optimal alternative that can increase crop yield, soil N content, and REN without stimulating N2O emissions.

Research progress on plant stress-associated protein (SAP) family: Master regulators to deal with environmental stresses.

Every year, unfavorable environmental factors significantly affect crop productivity and threaten food security. Plants are sessile; they cannot move to escape unfavorable environmental conditions, and therefore, they activate a variety of defense pathways. Among them are processes regulated by stress-associated proteins (SAPs). SAPs have a specific zinc finger domain (A20) at the N-terminus and either AN1 or C2H2 at the C-terminus. SAP proteins are involved in many biological processes and in response to various abiotic or biotic constraints. Most SAPs play a role in conferring transgenic stress resistance and are stress-inducible. The emerging field of SAPs in abiotic or biotic stress response regulation has attracted the attention of researchers. Although SAPs interact with various proteins to perform their functions, the exact mechanisms of these interactions remain incompletely understood. This review aims to provide a comprehensive understanding of SAPs, covering their diversity, structure, expression, and subcellular localization. SAPs play a pivotal role in enabling crosstalk between abiotic and biotic stress signaling pathways, making them essential for developing stress-tolerant crops without yield penalties. Collectively, understanding the complex regulation of SAPs in stress responses can contribute to enhancing tolerance against various environmental stresses through several techniques such as transgenesis, classical breeding, or gene editing.

Loss of OsMATE6 Function Enhances Drought Resistance Without Yield Penalty by Regulating Stomatal Closure in Rice.

Drought is one of the most severe environmental factors limiting plant growth and crop yield, necessitating the identification of genes that enhance drought resistance for crop improvement. Through screening an ethyl methyl sulfonate-mutagenized rice mutant library, we isolated the PEG tolerance mutant 97-1 (ptm97-1), which displays enhanced resistance to osmotic and drought stress, and increased yield under drought conditions. A point mutation in OsMATE6 was identified as being associated with the drought-resistant phenotype of ptm97-1. The role of OsMATE6 in conferring drought resistance was confirmed by additional OsMATE6 knockout mutants. OsMATE6 is expressed in guard cells, shoots and roots and the OsMATE6-GFP fusion protein predominantly localizes to the plasma membrane. Our ABA efflux assays suggest that OsMATE6 functions as an ABA efflux transporter; mutant protoplasts exhibited a slower ABA release rate compared to the wild type. We hypothesize that OsMATE6 regulates ABA levels in guard cells, influencing stomatal closure and enhancing drought resistance. Notably, OsMATE6 knockout mutants demonstrated greater yields under field drought conditions compared to wild-type plants, highlighting OsMATE6 as a promising candidate for improving crop drought resistance.

Dissecting the genetic basis of resistance to Soil-borne cereal mosaic virus (SBCMV) in durum wheat by bi-parental mapping and GWAS

Soil-borne cereal mosaic virus (SBCMV), the causative agent of wheat mosaic, is a Furovirus challenging wheat production all over Europe. Differently from bread wheat, durum wheat shows greater susceptibility and stronger yield penalties, so identification and genetic characterization of resistance sources are major targets for durum genetics and breeding. The Sbm1 locus providing high level of resistance to SBCMV was mapped in bread wheat to the 5DL chromosome arm (Bass in Genome 49:1140–1148, 2006). This excluded the direct use of Sbm1 for durum wheat improvement. Only one major QTL has been mapped in durum wheat, namely QSbm.ubo-2B, on the 2BS chromosome region coincident with Sbm2, already known in bread wheat as reported (Bayles in HGCA Project Report, 2007). Therefore, QSbm.ubo-2B = Sbm2 is considered a pillar for growing durum in SBCMV-affected areas. Herein, we report the fine mapping of Sbm2 based on bi-parental mapping and GWAS, using the Infinium 90 K SNP array and high-throughput KASP®. Fine mapping pointed out a critical haploblock of 3.2 Mb defined by concatenated SNPs successfully converted to high-throughput KASP® markers coded as KUBO. The combination of KUBO-27, wPt-2106-ASO/HRM, KUBO-29, and KUBO-1 allows unequivocal tracing of the Sbm2-resistant haplotype. The interval harbors 52 high- and 41 low-confidence genes, encoding 17 cytochrome p450, three receptor kinases, two defensins, and three NBS-LRR genes. These results pave the way for Sbm2 positional cloning. Importantly, the development of Sbm2 haplotype tagging KASP® provides a valuable case study for improving efficacy of the European variety testing system and, ultimately, the decision-making process related to varietal characterization and choice.

An AP2/ERF transcription factor confers chilling tolerance in rice.

Cold stress, a prominent adverse environmental factor, severely hinders rice growth and productivity. Unraveling the complex mechanisms governing chilling tolerance in rice is crucial for molecular breeding of cold-tolerant varieties. Here, we identify an APETALA2/Ethylene Responsive Factor (AP2/ERF) transcription factor, OsERF52, as a positive modulator in response to low temperatures. OsERF52 directly regulates the expression of C-Repeat Binding Factor (CBF) genes in rice. In addition, Osmotic Stress/ABA-Activated Protein Kinase 9-mediated phosphorylation of OsERF52 at S261 enhances its stability and interaction with Ideal Plant Architecture 1 and OsbHLH002/OsICE1. This collaborative activation leads to the expression of OsCBFs, thereby initiating the chilling response in rice. Notably, plants with base-edited OsERF52S261D-3HA exhibit enhanced chilling resistance without yield penalty. Our findings unveil the mechanism orchestrated by a regulatory framework involving a protein kinase and transcription factors from diverse families, offering potential genetic resources for developing chilling-tolerant rice varieties.

Participatory evaluation and demonstration of furrow irrigation systems with full irrigation application on Onion (Allium cepa L.) yield, yield component and water use efficiency at Docha Dembela in Demba Gofa woreda, South Ethiopia

Poor irrigation water management is one of the major factors limiting crop production in Ethiopia. Field experiment was conducted at farmers filed at Docha Dambal kebele in Demba Gofa woreda, Gofa zone, South Ethiopia for two consecutive years (2019 & 2020) to evaluate and demonstrate the effect of furrow irrigation systems on onion yield and water use efficiency. The treatments consisted of three furrow irrigation systems (conventional, alternative and fixed). The irrigation treatments were laid out in randomized complete block design with six replications and participant farmers were used as a replication. Results indicated that highest mean value of marketable bulb yield (27758.2 kg ha-1) was brought under Conventional furrow system. However the lowest mean value of marketable bulb yield was recorded from the fixed furrow system (20482.5). However, Superior water use efficiency of 13.33kg/m3 was recorded from alternative furrow irrigation system. The lowest water use efficiency (7.78 kg/m3) was recorded from the Conventional furrow system. Therefore, It could be concluded that alternate furrow irrigation system maximized water use efficiency of onion with tolerable yield penalty at the study area. This result is important for farmers to irrigate supplemental lands with water saved, thus achieving a more efficient and rational use of land and water resources in the water limited area. If areas with no water scarcity, conventional furrow system could be a potential approach for promoting onion bulb yield under field conditions.