Extreme heat driven by climate change poses a catastrophic threat to global vegetable production, undermining nutritional security because of the heightened physiological sensitivity and succulent tissues of these crops. This review synthesizes the multistage impacts of heat stress across critical developmental phases—from germination to reproduction—emphasizing morphological impairments (such as leaf wilting and floral abortion) and physiological disruptions (including photosynthetic inhibition and oxidative damage). We systematically dissect thermotolerance mechanisms in vegetables, highlighting transcriptional reprogramming by HSFs, WRKY, and NAC transcription factors; chaperone-mediated proteostasis via HSPs; epigenetic remodeling; Ca2+-ROS signaling pathways; and the role of phase separation dynamics. Importantly, we propose six strategic pathways to develop heat-resilient vegetables: harnessing natural variation through pan-genome-driven allele mining; employing biotechnological interventions such as CRISPR-mediated editing and synthetic promoters; engineering multistress tolerance by targeting conserved ‘core response’ pathways; exploiting epigenetic memory to achieve transgenerational resilience; optimizing source-sink dynamics with ‘’Climate-Responsive Carbon Optimization; and applying plant growth regulators and nanotechnology to enhance thermotolerance. Together, these strategies chart a clear roadmap for climate-smart vegetable breeding and call for interdisciplinary collaboration to translate molecular discoveries into practical breeding approaches for sustainable food systems under escalating thermal extremes.

Light is vital for plant growth and development, and the germination of many plant seeds and the development of seedlings are very sensitive to the light environment. Under no or low light conditions, pepper seedlings will accelerate the elongation of the hypocotyl to obtain light. To elucidate the molecular mechanism by which light regulates hypocotyl elongation in pepper, RNA sequencing was performed to analyze the hypocotyls and cotyledons of the yellowing mutant R24 under three different light intensity treatments. A total of 35,341 gene were identified; moreover, during the treatment, 9695 new genes and 13,123 differentially expressed genes (DEGs) were observed, respectively. Some genes related to brassino-lide receptor protein kinase BRI1, light capture proteins LHCA and LHCB, and auxin response factor may regulate the response of hot pepper cotyledons and hypocotyls to different light intensity. KEGG functional enrichment analysis revealed that the most abundant pathways were phenylpropane biosynthesis, plant hormone signal transduction, and carbon metabolism. This study provides a valuable reference for understanding the molecular mechanism of pepper’s response to different light intensities at the seedling stage and for improving the local light environment to overcome the hypocotyl elongation of pepper crop under low light conditions.

Pepper is a major horticultural crop cultivated extensively worldwide. Among its various agronomic characteristics, fruit length is a key trait influencing both yield and visual quality. Despite its importance, the genetic mechanisms regulating fruit length in Capsicum remain insufficiently characterized, hindering the development of high-yielding and aesthetically desirable cultivars. In this study, fruits at three developmental stages (0, 15, and 30 days after flowering) were sampled from the long-fruit mutant fe1 and its wild-type progenitor LY0. Phenotypic characterization and transcriptomic sequencing were conducted to identify candidate genes associated with fruit length regulation. Morphological analysis revealed that the most pronounced difference in fruit length occurred at 30 days after flowering. RNA-seq analysis identified 41,194 genes, including 13,512 differentially expressed genes (DEGs). Enrichment analysis highlighted key pathways, such as plant–pathogen interaction, plant hormone signal transduction, and the MAPK signaling pathway. DEG classification suggested that several downregulated genes related to early auxin responses may contribute to the regulation of fruit elongation. Notably, the gibberellin signaling gene SCL13 (Caz12g26660), transcription factors MYB48 (Caz11g07190) and ERF3-like (Caz10g00810), and the cell-wall-modifying gene XTH15-like (Caz07g19100) showed significantly elevated expression in 30-day-old fruits of fe1. Weighted gene co-expression network analysis (WGCNA) further revealed a strong positive correlation among these genes. Quantitative RT-PCR analysis of eight selected DEGs confirmed the RNA-seq results. This study provides a foundational framework for dissecting the molecular regulatory network of fruit length in Capsicum, offering valuable insights for breeding programs.

To address the current mismatch between processing pepper cultivars and the requirements of mechanized production, this study aims to construct a comprehensive evaluation model for the suitability of mechanized transplanting and harvesting, thereby screening highly adaptable varieties. An evaluation system comprising eight indicators for the transplanting stage and thirteen indicators for the harvesting stage was established using 105 processing pepper varieties (including 56 erect-fruit and 49 pendent-fruit peppers). Variation analysis, hierarchical clustering, principal component analysis (PCA), and Pearson correlation analysis were integrated to reveal the clustering effects of the cultivars and the synergistic and antagonistic relationships among the indicators. Furthermore, a combined CRITIC–VIKOR model was applied to conduct a multi-criteria comprehensive ranking of mechanization suitability. The results indicated that the biomechanical properties of processing peppers exhibited a significantly higher degree of variation than conventional morphological indicators (e.g., the coefficient of variation for lodging resistance reached 93.60%). Significant differences were observed in the mechanization adaptation mechanisms between the two pepper types: erect-fruit peppers were primarily limited by fruiting branch toughness (weight: 5.907%), whereas pendent-fruit peppers were mainly constrained by fruit morphological uniformity. Compared with the traditional PCA model, the CRITIC–VIKOR model effectively identified varieties with critical biomechanical defects by constraining the “individual regret value”, which highly aligns with Liebig’s Law of the Minimum in mechanized operations. Based on this model, varieties with superior comprehensive mechanization adaptability were successfully identified, notably C21, C55, and C23 (erect-fruit peppers), and D20, D11, and D19 (pendent-fruit peppers). This study provides a theoretical foundation and mathematical modeling support for the directional breeding of mechanization-suitable cultivars, the integration of agronomy and agricultural machinery, and the quantitative evaluation of multi-trait pyramiding in processing peppers.