Molecular insights and translational opportunities to enhance heat tolerance in rice

Heat stress impact on rice reproductive processes: challenges and new approaches

Heat stress represents one of the most severe abiotic constraints to rice ( Oryza sativa L.) productivity and is expected to intensify under ongoing climate change, particularly affecting the reproductive phase and leading to substantial yield and grain quality losses. This review synthesizes current knowledge on the impacts of heat stress on rice reproduction, with a focus on both male and female reproductive structures and their interactions. Evidence from anatomical, physiological, transcriptomic, and metabolomic studies to describe how elevated temperatures disrupt key reproductive processes, including microsporogenesis, anther dehiscence, pollen viability, pollen-pistil interactions, fertilisation, and embryo sac development were integrated in this review. It further discusses the genotype-dependent differences in reproductive thermotolerance; and key genes, metabolites, and pathways associated with heat stress perception, signalling, and tolerance are highlighted. Finally, it is briefly discussed how recent advances in breeding strategies, functional genomics and genome-editing technologies, particularly CRISPR-based approaches, are providing new opportunities to enhance reproductive resilience to heat stress and how it is essential to close the existing molecular knowledge gaps in the development of heat-tolerant rice varieties capable of sustaining productivity in a warming climate.

Decoding Heat Tolerance in Rice: Physiological Mechanisms, Genetic Architecture, and Breeding Innovations

Leveraging transcriptional, genomic, and epigenetic regulatory layers to enhance abiotic stress resilience in grapevine

Grapevine (Vitis vinifera), an industry valued at approximately 108.61 billion US dollars globally, faces escalating threats from abiotic stresses that intensify under climate change and increasingly compromise berry quality, phenology, and yield. Despite decades of molecular characterization, translating stress biology knowledge into climate-resilient cultivars remains limited. We argue this gap reflects not a lack of knowledge within individual biological layers, but a fundamental failure to integrate across them. Grapevine stress tolerance operates through three interconnected regulatory layers. Transcription factor networks, WRKY, NAC, MYB, DREB, and bZIP families, constitute the most rapid layer, converging on shared ABA-mediated signaling hubs despite apparent stress-type specificity. Quantitative trait loci and genome-wide association studies capture the genomic architecture underlying these responses, yet remain critically under characterized for drought, salinity, and heavy metal tolerance. Epigenetic regulation through DNA methylation, histone modifications, and stress memory mechanisms constitutes a temporally durable third layer, uniquely important for perennial crops where adaptive chromatin states persist across growing seasons. Critically, these layers are not independent: transcription factor activity shapes the chromatin landscape, epigenetic marks modulate QTL expression, and genomic loci encode the regulatory machinery executing stress responses. Current breeding tools, marker-assisted selection, CRISPR/Cas9, and epigenomic selection, map onto these three layers but are overwhelmingly applied in isolation, limiting their collective impact. This review synthesizes knowledge gaps across all three layers within a unified hierarchical framework, arguing that deliberate cross-layer integration through multi-omics and precision breeding could enable cultivars capable of sustaining productivity under a rapidly changing climate.

Genomic architecture and molecular regulation underlying heat-induced bolting in lettuce

Premature bolting under elevated temperatures is a major constraint on lettuce production because it shortens the vegetative harvest period and reduces leaf quality. Bolting, floral transition, and flowering are closely connected but distinguishable processes that are regulated by overlapping genetic and environmental factors. Recent advances in lettuce genome assemblies, super-pangenomes, population resources, multi-omics analyses, and genome editing have enabled a more integrated understanding of this complex trait. This review summarizes the genomic architecture and natural variation associated with reproductive timing, the integration of temperature with photoperiodic and stress-responsive pathways, and the hormonal and metabolic changes that support inflorescence stem elongation. Particular attention is given to phytochrome-associated variation, heat-responsive transcription factors, LsSOC1, auxin and gibberellin signaling, and carbohydrate remodeling. We further discuss how these findings can inform genome editing, marker-assisted and genomic selection, and cultivation strategies. Together, current evidence indicates that heat-induced bolting arises from coordinated environmental signal integration, reproductive commitment, and hormone-dependent stem growth rather than from a single linear thermosensory pathway.

Integrating molecular networks and physiological adaptation for heat-resilient crops.

As global temperatures increase, heat stress has become a key limiting factor affecting crop yield and quality. Against the backdrop of growing global food demand and increasingly frequent extreme high-temperature events, this dual pressure poses a threat to global food security. This review systematically analyzes the physiological effects of heat on major crops, focusing on source-sink relationships and nutrient transport processes. We summarize key heat-related genes identified in these crops through forward and reverse genetic approaches, elucidating the mechanisms underlying heat signal perception and transduction across genetic, transcriptional, protein, metabolic, cell membrane, nuclear, and organellar levels. Furthermore, we explore the complex crosstalk between heat and other abiotic/biotic stresses in crops. Finally, we discuss current challenges and future avenues for breeding heat-resilient crops to ensure stable agricultural productivity.

Multi-omics links short-term epigenetic plasticity to long-term genetic adaptation to heat stress in a montane tree species.

A near telomere-to-telomere genome assembly of Populus wilsonii, a montane tree species endemic to the eastern Hengduan Mountains, offers novel insights into how forest trees balance transient epigenetic flexibility with enduring genetic stability to survive accelerating climate change.