Strong artificial and natural selection causes the formation of highly conserved haplotypes that harbor agronomically important genes. GWAS combination with haplotype analysis has evolved as an effective method to dissect the genetic architecture of complex traits in crop species. We used the 60 K Brassica Infinium SNP array to perform a genome-wide analysis of haplotype blocks associated with oleic acid (C18:1) in rapeseed. Six haplotype regions were identified as significantly associated with oleic acid (C18:1) that mapped to chromosomes A02, A07, A08, C01, C02, and C03. Additionally, whole-genome sequencing of 50 rapeseed accessions revealed three genes (BnmtACP2-A02, BnABCI13-A02 and BnECI1-A02) in the A02 chromosome haplotype region and two genes (BnFAD8-C02 and BnSDP1-C02) in the C02 chromosome haplotype region that were closely linked to oleic acid content phenotypic variation. Moreover, the co-expression network analysis uncovered candidate genes from these two different haplotype regions with potential regulatory interrelationships with oleic acid content accumulation. Our results suggest that several candidate genes are closely linked, which provides us with an opportunity to develop functional haplotype markers for the improvement of the oleic acid content in rapeseed.

Rice plants are highly sensitive to high-temperature stress, posing challenges to grain yield and quality. However, the impact of high temperatures on the quality of high-quality hybrid rice during the booting stage, as well as the differing effects of the booting and grain-filling stages on grain quality, are currently not well-known. Therefore, four high-quality hybrid rice were subjected to control (CK) and high-temperature stress during the booting (HT1) and grain-filling stages (HT2). Compared to the control, HT1 significantly reduced the spikelets panicle⁻¹ (16.1%), seed setting rate (67.5%), and grain weight (7.4%), while HT2 significantly reduced the seed setting rate (6.0%) and grain weight (7.4%). In terms of quality, both HT1 and HT2 significantly increased chalkiness, chalky grain rate, gelatinization temperature, peak viscosity (PV), trough viscosity (TV), final viscosity (FV), and protein content in most varieties, and significantly decreased grain length, grain width, total starch content, and amylose content. However, a comparison between HT1 and HT2 revealed that the increase in chalkiness, chalky grain rate, PV, TV, and FV was greater under HT2. HT1 resulted in a greater decrease in grain length, grain width, total starch content, and amylose content, as well as an increase in protein content. Additionally, HT1 led to a significant decrease in amylopectin content, which was not observed under HT2. Therefore, future efforts in breeding and cultivating high-quality hybrid rice should carefully account for the effects of high temperatures at different stages on both yield and quality.

Stem rot caused by Sclerotinia sclerotiorum poses a significant threat to global agriculture, leading to substantial economic losses. To explore innovative integrated pest management strategies and elucidate the underlying mechanisms, this study examined the impact of nano-silicon on enhancing resistance to Sclerotinia sclerotiorum in Brassica napus. Bacteriostatic assays revealed that nano-silicon effectively inhibited the mycelial growth of Sclerotinia sclerotiorum in a dose-dependent manner. Field trials corroborated the utility of nano-silicon as a fertilizer, substantially bolstering resistance in the Brassica napus cultivar Xiangyou 420. Specifically, the disease index was reduced by 39–52% across three distinct geographical locations when compared to untreated controls. This heightened resistance was attributed to nano-silicon’s role in promoting the accumulation of essential elements such as silicon (Si), potassium (K), and calcium (Ca), while concurrently reducing sodium (Na) absorption. Furthermore, nano-silicon was found to elevate the levels of soluble sugars and lignin, while reducing cellulose content in both leaves and stems. It also enhanced the activity levels of antioxidant enzymes. Transcriptomic analysis revealed 22,546 differentially expressed genes in Si-treated Brassica napus post-Sclerotinia inoculation, with the most pronounced transcriptional changes observed one day post-inoculation. Weighted gene co-expression network analysis identified a module comprising 45 hub genes that are implicated in signaling, transcriptional regulation, metabolism, and defense mechanisms. In summary, nano-silicon confers resistance to Brassica napus against Sclerotinia sclerotiorum by modulating biochemical defenses, enhancing antioxidative activities, and rapidly reprogramming key resistance-associated genes. These findings contribute to our mechanistic understanding of Si-mediated resistance against necrotrophic fungi and offer valuable insights for the development of stem-rot-resistant Brassica napus cultivars.

Cadmium (Cd) contamination and rising temperatures pose significant challenges to rice growth and food safety. Here, we investigated growth responses, Cd accumulation, physiological adaptations, and transcriptomic profiles of two rice cultivars, Yuzhenxiang (YZX) and Xiangwanxian 12 (XWX12), under combined Cd (0, 5, 20 μmol L⁻¹) and temperature (25 °C, 30 °C) stress. Moderate warming (30 °C) generally promoted seedling growth and enhanced Cd uptake, with YZX showing greater increases in plant height and biomass, whereas XWX12 developed longer roots. At maturity, the temperature-induced growth advantage persisted in YZX, accompanied by a 60% increase in root Cd concentration, compared with 36% in XWX12. Antioxidant enzyme activities (POD, SOD, CAT) were significantly induced under combined stress, with XWX12 exhibiting stronger enzymatic responses and broader activation of ABC transporter genes, supporting reduced Cd accumulation in shoots. Malondialdehyde content indicated milder oxidative damage in YZX despite higher Cd accumulation. Transcriptomic analyses revealed extensive early transcriptional reprogramming, with enrichment of antioxidant metabolism, ABC transporters, MAPK signaling, and Cd transport-related genes, demonstrating coordinated physiological and molecular responses. XWX12 favored intracellular Cd sequestration and sustained antioxidant activation, whereas YZX relied more on uptake and translocation processes. Overall, these results highlight genotype-specific strategies in coping with combined Cd and temperature stress, providing mechanistic insights for improving rice tolerance and safety under warming and contaminated environments.