Understanding of the underlying genetic, biochemical, and physiological mechanisms that enable legume crops to tolerate high temperatures

The gap

Evidence profile

Sourced from the conclusions and future work and stated research gap of the source papers, classified as general, drawn from work published between 2024 and 2026, spanning 4 journals. Those papers have been cited 78 times in total.

Supporting evidence — 6 representative gaps

• Integrated transcriptomic and metabolomic analysis reveals the regulatory networks in response to heat stress in Pleurotus pulmonarius (2026) · International Microbiology · doi

  Future research should focus on targeted engineering of these metabolic nodes, particularly through breeding or gene editing approaches, to develop heat-tolerant cultivars with enhanced resilience and stable production under ele- vated temperatures. While our findings offer valuable insights into the molecular basis of thermotolerance, the present study is limited to a single time point under acute heat stress, and further functional validation via genetic manipulation is warranted to confirm the causal roles of the identified path- ways.

  generalconclusions
  Keywords: heat future focus targeted engineering metabolic nodes particularly breeding gene editing approaches develop tolerant cultivars
• Molecular Targets and Trait Innovation in CRISPR-Edited Vegetable Crops: An Up-to-Date Review (2020–2026) (2026) · Plants · doi

  CRISPR/Cas genome-editing research has been widely applied in the years 2020–2026 in various vegetable crops. Tomato and potato crops remain at the forefront and have drawn most of the research interest due to their importance, with the main edited trait for both crops being biotic stress resistance. Across trait categories, research that aims to confer biotic stress resistance, by targeting host susceptibility genes, is the dominant focus because of the enormous global losses that are imposed by pathogenic organisms on vegetable production. Some of the most significant advances of the past years are the DMR6/S5H gene family as a target for many crops to confer resistance to pathogens from different kingdoms, the eIF4E family for broad-spectrum viral resistance, and the MLO family for powdery mildew resistance across multiple species. While traditional plant breeding approaches are time consuming and non-specific, plant breeding systems can be strengthened with the utilization of the CRISPR/Cas system and serve the current farmer and consumer needs. Despite the challenges the CRISPR/Cas system faces, it remains one of the most promising tools in vegetable crop breeding, and since it has such huge potential it is expected to overcome its remaining challenges and have a central role in meeting the demands of food security, nutritional quality and agricultural sustainability in a changing climate. Despite remarkable progress, several technical challenges persist and remain laborious. Polyploidy requires the simultaneous disruption of all relevant homoeologous alleles and demands high efficiency in multiplex editing. Transformation recalcitrance in many vegetable species and genotypes continues to limit the speed at which validated targets can be transferred to commercial cultivars. Off-target activity remains a concern, although it has been reduced by high-fidelity Cas9 variants and RNP delivery. Therefore, the development of a truly efficient and universally applicable transformation and regeneration system for diverse vegetable crops is a critical priority. Future applications of CRISPR/Cas in vegetable crop improvement include the adop- tion of multiple techniques. Prime and base editing can cause precise nucleotide substitu- tions and preserve gene function while they alter specific regulatory or catalytic residues. Multiplex editing can be utilized for the simultaneous stacking of multiple favorable traits within elite cultivar backgrounds in single transformation events; de novo domestication of wild relatives that carry valuable alleles, which confer stress tolerance or have nutri- https://doi.org/10.3390/plants15182885 Plants 2026, 15, 2885 19 of 29 tional value, and are absent from current breeding germplasm; and engineer chromosomal recombination to break the linkage drag that accompanies conventional introgression. The current European regulatory system, which previously classified all genome- edited plants as GMOs, had long been a barrier to commercialization. However, the European Parliament and the Council reached a provisional political agreement in De- cember 2025, which was formally adopted as Regulation (EU) 2026/1388 on 17 June 2026, marking a major shift toward a more permissive framework for certain genome-edited plants. This latest adoption of the new NGT legislation, alongside already permissive frameworks in other major regions, offers an increasingly favorable environment for the commercialization of CRISPR-edited vegetable crops in Europe. Author Contributions: Conceptualization, V.P., and I.G.; methodology, V.P., E.D. and I.G.; investiga- tion, V.P., E.D. and I.G.; writing, original draft preparation, E.D.; writing—review and editing, V.P., E.D. and I.G.; visualization, E.D., supervision, V.P., and I.G.; project administration, V.P. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding. Data Availability Statement: No new data were created or analyzed in this study. Data sharing is not applicable to this article. Acknowledgments: During the preparation of this manuscript, the authors used ChatGPT (GPT-5, OpenAI, San Francisco, CA, USA) for language refinement and grammatical editing. The authors have reviewed and edited the output and take full responsibility for the content of this publication. Conflicts of Interest: The authors declare no conflicts of interest.

  generalfuture work
  Keywords: vegetable editing crops crispr edited resistance breeding system plants authors genome interest stress confer family
• Rice Heat Stress Response: Physiological Changes and Molecular Regulatory Network Research Progress (2025) · Plants · cited 13× · doi

  High temperature stress remains one of the most critical environmental constraints on rice production worldwide, exacerbated by the increasing frequency and intensity of extreme heat events under climate change. Its impact extends across multiple growth stages, threatening both yield and grain quality, and posing serious challenges to hybrid seed production. While significant progress has been made in elucidating the physio- logical, molecular, and genetic basis of thermotolerance, the effective translation of these findings into breeding solutions that are robust across diverse environments remains a formidable task. Plants 2025, 14, 2573 18 of 26 6.1. Breeding Strategies Utilizing Existing Resources Accelerating the development of thermotolerant rice cultivars requires the strategic use of existing genetic resources. Natural germplasm, including wild rice species and landraces, offers abundant allelic variation for heat adaptation. Several functional genes associated with heat tolerance, such as TT1, QT12, NAT1, and TT3.1 [28,119,130,134], have been identified and represent valuable targets for improvement. A practical approach is to combine multiple favorable alleles into elite cultivars through gene pyramiding. This can be achieved by crossing high-performing but heat- sensitive cultivars with thermotolerant donor lines, followed by marker-assisted selection (MAS) or genomic selection (GS) to track and select desirable alleles. High-throughput phenotyping platforms further facilitate large-scale, non-destructive evaluation of traits such as canopy temperature, chlorophyll fluorescence, and spikelet fertility under both field and controlled-environment conditions. Emerging approaches, including speed breed- ing, artificial intelligence (AI)-driven parental selection, and gene editing, offer additional avenues for enhancing thermotolerance in elite cultivars while shortening breeding cycles. Despite these promising strategies, their effectiveness can be constrained by variable perfor- mance of heat-tolerant genes across environments, the underutilization of wild germplasm due to linkage drag and poor adaptation, and the lengthy breeding cycles required for introgression. Addressing these limitations requires a more integrated view of the technical, biological, and environmental barriers that influence the success of functional genomics in practical breeding. 6.2. Translational Challenges in Breeding Heat-Tolerant Rice While advances in molecular marker technology, genomic selection, and precision gene editing provide powerful opportunities to accelerate the development of heat-tolerant rice cultivars, their practical translation into breeding programs remains challenging. Heat tolerance is inherently polygenic, and most favorable alleles exert only small individual ef- fects, making it difficult to achieve substantial gains through single-gene interventions. The utilization of valuable germplasm is further complicated by adaptation gaps

  generalfuture work
  Keywords: heat breeding rice cultivars gene selection high remains across germplasm adaptation practical alleles tolerant temperature
• Epigenetic Regulation for Heat Stress Adaptation in Plants: New Horizons for Crop Improvement under Climate Change (2024) · Agronomy · cited 46× · doi

  Gaining a profound understanding of the epigenetic regulation of heat stress responses in plants sheds light on the intricate mechanisms underlying thermotolerance. Leveraging this knowledge can propel the development of innovative breeding strategies, aimed at cultivating heat-resilient crop varieties, which are paramount in mitigating the impacts of global warming. Integrating epigenetic modifications into plant breeding holds im- mense promise for bolstering crop resilience and safeguarding sustainable agricultural productivity amidst shifting climatic conditions. Epigenetic modifications, encompassing DNA methylation, histone alterations, and RNA modifications, serve as pivotal regulators of plant heat stress responses. These modifications dynamically and heritably influence gene expression, empowering plants to adapt to and retain memories of stress encounters. Specifically, DNA methylation fine-tunes the expression of stress-responsive genes, histone modifications foster transcriptional memory, while RNA modifications fine-tune the stabil- ity and translation of stress-associated mRNAs. Collectively, these epigenetic mechanisms reinforce plant thermotolerance, empowering them to withstand elevated temperatures with greater resilience. The implementation of heat stress-induced epigenetic modifiers in breeding pro- grams holds tremendous promise for cultivating crops with unparalleled climate resilience. By strategically manipulating epigenetic marks through traditional breeding techniques, epigenome editing advancements, and harnessing naturally occurring epigenetic variations, breeders can cultivate crop varieties with enhanced stress tolerance and superior adap- tive abilities. Advanced technologies, such as CRISPR-Cas9, offer precision in modifying epigenetic traits, precisely targeting stress-sensitive genes to bolster plant resilience. While the prospects are exciting, there remain pivotal challenges to be addressed. Chief among them is the need for a deeper understanding of the stability and heritability of epigenetic marks across generations, as certain modifications may exhibit reversibility or be influenced by environmental cues. Furthermore, the intricate interplay between diverse epigenetic marks and their combined impact on gene expression necessitates extensive research. Comprehensive studies are imperative to identify reliable epigenetic markers for selective breeding and to elucidate the underlying mechanisms governing epigenetic regulation of thermotolerance. Addressing these challenges will pave the way for the Agronomy 2024, 14, 2105 15 of 21 successful development of heat-resilient crops, ensuring global food security amidst the threat of climate change. Future research endeavors should prioritize elucidating the intricate interplay among various epigenetic modifications and their cumulative effects on gene expression patterns and plant stress responses. By seamlessly integrating epigenetics with traditional breedin

  generalfuture work
  Keywords: epigenetic stress modifications heat breeding plant resilience expression responses intricate mechanisms thermotolerance crop gene marks
• How Does Rice Cope with High-Temperature Stress During Its Growth and Development, Especially at the Grain-Filling Stage? (2025) · Agronomy · cited 19× · doi

  Global warming is an undeniable reality, and heat stress has become a significant limiting factor for safe rice production in China. Scientific research aimed at enhancing the heat tolerance of rice is crucial for ensuring food security. Future research on rice re- sponses to heat stress should focus on the following areas: (1) Heat-Tolerant Genetic Breeding: While traditional breeding and marker-assisted selection have made progress, CRISPR gene-editing technology offers higher efficiency. Identifying key genes associated with heat tolerance in rice, exploring heat-resistant gene resources, and utilizing genomic technologies (such as GWAS and QTL mapping) to screen for heat-related genes (e.g., heat shock proteins (HSPs), HSFA family transcription factors, and ROS-scavenging genes) are essential. Efforts should be made to develop heat-tolerant genes from wild rice and local varieties and to improve cultivars precisely through gene-editing techniques like CRISPR/Cas9. Synthetic biology can be employed to construct modular gene circuits for heat tolerance, leading to the development of climate-resilient rice that responds intelli- gently to heat stress. Additionally, it is vital to explore the synergistic regulatory mecha- nisms between heat tolerance and other stress resistances (such as drought and disease resistance) to cultivate multi-resistant varieties. (2) Regulatory Mechanisms: Although substantial research has been conducted on heat damage to rice production and rice responses to heat stress, the impact of heat stress on rice seed development war- rants further investigation. Key areas include: Heat-sensitive stages of rice: focus on the reproductive growth stages (e.g., pollen development, flowering, and grain filling) to elucidate response mechanisms, and analyze the physiological and molecular bases of pollen sterility, grain emptiness, and chalky en- dosperm formation. Organelle interactions and signal transduction: study how high temperatures impair chloroplast and mitochondrial functions and explore the regulatory networks of ROS sig- nal transmission and energy metabolism between organelles under heat stress. Agronomy 2025, 15, 623 13 of 17 Epigenetic regulation: investigate how DNA methylation, histone modifications, and other epigenetic changes under heat stress influence heat tolerance and develop epige- netic editing technologies. (3) Environmental Interactions and Ecological Adaptability: It is necessary to explore the synergistic responses to heat combined with other stresses, such as drought, intense light, high humidity, and salinity, to understand cross- adaptation mechanisms. The adaptability of heat-tolerant varieties across different cli- matic regions (e.g., tropical and subtropical zones) should be evaluated and geographic information systems (GIS) used to predict their potential for widespread adoption under future climate scenarios. (4) Intelligent Technologies and Interdisciplinary Integration: AI-Assisted breeding: leverage machine learning to integrate multi-omics data (genomics, transcriptomics, and metabolomics) for predicting heat-tolerant phenotypes and accelerating the breeding process. Synthetic biology applications: design artificial synthetic pathways to enhance antioxidant systems and heat-protective protein expression, creating engineered rice varieties with improved heat tolerance. (5) Socio-Economic and Policy Support: Variety promotion and farmer acceptance: assess the economic benefits of heat-tol- erant varieties and optimize their traits (e.g., balancing yield and taste) based on farmer needs. Climate adaptation policies: promote the inclusion of heat-tolerant rice in national climate-smart agriculture programs and establish disaster insurance and subsidy mecha- nisms. Advanced technologies such as remote sensing, GIS, and global positioning sys- tems should be integrated to develop comprehensive monitoring, early warning, and im- pact assessment systems for rice heat damage. Author Contributions: X.W. and F.L. designed the main conceptual ideas; F.L. and J.Q. wrote the manuscript; J.Q., L.C. and B.F. revised the manuscript. All authors have read and agreed to the published version of the manuscript. Funding: This work was supported by the National Natural Science Foundation of China (32401922); the Zhejiang Provincial Natural Science Foundation of China (LZ25C130011, LQ24C130007); and The Agricultural Science and Technology Innovation Program (ASTIP). Conflicts of Interest: The authors declare no conflicts of interest.

  generalfuture work
  Keywords: heat rice stress tolerance tolerant varieties breeding gene genes technologies climate china editing develop synthetic
• Mechanistic Insights into Negative Impacts of Heat Stress and the Mitigating Approaches in Legume Crops (2026) · Journal of Plant Growth Regulation · doi

  There is a lack of understanding of the underlying genetic, biochemical, and physiological mechanisms that enable legume crops to tolerate high temperatures. The paper identifies a gap in the development of effective strategies to mitigate the impacts of heat stress on legume crops. Further research is needed to explore the potential of heat-responsive genes and other approaches to improve heat tolerance in legumes.

  generalstated research gapevidence 4/5
  Keywords: there lack understanding underlying genetic biochemical physiological mechanisms

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