Traits related to flowering time are the most promising agronomic traits that directly impact the seed yield and oil quality of rapeseed (Brassica napus L.). Developing early flowering and maturity rapeseed varieties is an important breeding objective in B. napus. Many studies have reported on days to flowering, but few have reported on budding, bolting, and the interval between bolting and DTF. Therefore, elucidating the genetic architecture of QTLs and genes regulating flowering time, we presented an integrated investigation on SNP and haplotype-based genome-wide association study of 373 diverse B. napus germplasm, which were genotyped by the 60K SNP array and were phenotyped in the four environments. The results showed that a total of 15 and 37 QTLs were detected from SNP and haplotype-based GWAS, respectively. Among them, seven QTL clusters were identified by haplotype-based GWAS. Moreover, three and eight environmentally stable QTLs were detected by SNP-GWAS and haplotype-based GWAS, respectively. By integrating the above two approaches and by co-localizing the four traits, ten (10) genomic regions were under selection on chromosomes A03, A07, A08, A10, C06, C07, and C08. Interestingly, the genomic regions FT.A07.1, FT.A08, FT.C06, and FT.C07 were identified as novel. In these ten regions, a total of 197 genes controlling FT were detected, of which 14 highly expressed DEGs were orthologous to 13 Arabidopsis thaliana genes after integration with transcriptome results. In a nutshell, the above results uncovered the genetic architecture of important agronomic traits related to flowering time and provided a basis for multiple molecular marker-trait associations in B. napus.

Three Solanaceae hosts (TSHs), S. tuberosum, N. benthamiana and S. lycopersicum, represent the three major phylogenetic clades of Solanaceae plants infected by Phytophthora infestans, which causes late blight, one of the most devastating diseases seriously affecting crop production. However, details regarding how different Solanaceae hosts respond to P. infestans are lacking. Here, we conducted RNA-seq to analyze the transcriptomic data from the TSHs at 12 and 24 h post P. infestans inoculation to capture early expression effects. Macroscopic and microscopic observations showed faster infection processes in S. tuberosum than in N. benthamiana and S. lycopersicum under the same conditions. Analysis of the number of genes and their level of expression indicated that distinct response models were adopted by the TSHs in response to P. infestans. The host-specific infection process led to overlapping but distinct in GO terms and KEGG pathways enriched for differentially expressed genes; many were tightly linked to the immune response in the TSHs. S. tuberosum showed the fastest response and strongest accumulation of reactive oxygen species compared with N. benthamiana and S. lycopersicum, which also had similarities and differences in hormone regulation. Collectively, our study provides an important reference for a better understanding of late blight response mechanisms of different Solanaceae host interactions.

Rapeseed (Brassica napus L.) is an important crop for healthy edible oil and stockfeed worldwide. However, its growth and yield are severely hampered by black rot, a destructive disease caused by Xanthomonas campestris pv. campestris (Xcc). Despite the identification of several quantitative trait loci (QTLs) associated with resistance to black rot in Brassica crops, the underlying molecular mechanisms remain largely unexplored. In this study, we investigated Xcc-induced transcriptomic and metabolic changes in the leaves of two rapeseed varieties: Westar (susceptible) and ZS5 (resistant). Our findings indicated that Xcc infection elicited more pronounced overall transcriptomic and metabolic changes in Westar compared to ZS5. Transcriptomic analyses revealed that the phenylpropanoid biosynthesis, cutin, suberine and wax biosynthesis, tryptophan metabolism, and phenylalanine metabolism were enriched in both varieties. Notably, photosynthesis was down-regulated in Westar after infection, whereas this down-regulation occurred at a later stage in ZS5. Integrated analyses of transcriptome and metabolome revealed that the tryptophan metabolism pathway was enriched in both varieties. Indolic glucosinolates and indole-3-acetic acid (IAA) are two metabolites derived from tryptophan. The expression of genes involved in the indolic glucosinolate pathway and the levels of indolic glucosinolates were significantly elevated in both varieties post-infection. Additionally, exogenous application of IAA promoted the development of black rot, whereas the use of an IAA synthesis inhibitor attenuated black rot development in both resistant and susceptible rapeseed varieties. These findings provide valuable molecular insights into the interactions between rapeseed and Xcc, facilitating the advancement of black rot resistance breeding in Brassica crops.

Phytosterols are a group of nonpharmacological alternatives to prevent or control dyslipidemias and cardiovascular disease. Increasing the phytosterol content in rapeseed oil is important to enhance daily phytosterol intake. However, the mechanisms of biosynthesis and regulation of phytosterol in rapeseed remain unclear. In this study, two representative rapeseed cultivars with extremely high (H286) and low (H174) phytosterol content were selected and treated with various concentrations (0.5−5.0 mM) of methyl jasmonate (MeJA). The results showed that treatment with 1 mM MeJA increased the phytosterol content of H174 and H286 by 17% and 27%, respectively. Based on the multiomics data, a gene‐phytosterol regulatory network was constructed. We deduced that MeJA down‐regulated the expression level of BnaA07.SCL15, BnaC05.MYB61, and BnaC03.AGL2, thereby promoting the phytosterol biosynthesis , and which were validated through the transient expression in tobacco. Notably, overexpression of Arabidopsis BnaA07.SCL15 exhibited a significant decrease in their phytosterol content. Additionally, an integrative analysis of the high‐resolution metabolome and transcriptome revealed that the accumulation patterns of 997 metabolites were highly correlated with their corresponding gene expression patterns. MeJA also significantly affected flavonoid biosynthesis, α‐linolenic acid metabolism, and amino acid metabolism. Furthermore, BnaA09.TT8 and BnaC09.TT8 were found to regulate of flavonoids. Overall, this study provides valuable insights into the phytosterol biosynthesis in rapeseed and offers a simple and effective approach for improving rapeseed quality.

Lead (Pb) severely impairs plant growth, yet the role of WRKY transcription factors in Pb tolerance in maize remains largely unknown. Here, we identified a Pb-responsive WRKY transcription factor, ZmWRKY4, whose transcript levels were rapidly and strongly induced in maize leaves following Pb exposure. Physiological and biochemical analyses showed that overexpression of ZmWRKY4 substantially enhanced Pb tolerance in maize. Transgenic lines exhibited significantly lower malondialdehyde (MDA) levels and reduced electrolyte leakage than wild-type plants. In addition, ZmWRKY4 overexpression increased catalase (CAT) activity and effectively limited H₂O₂ accumulation. Further analyses revealed that ZmWRKY4 positively regulates ZmCAT1, a key antioxidant gene involved in H₂O₂ scavenging, under Pb stress. Electrophoretic mobility shift assays and ChIP-qPCR collectively confirmed that ZmWRKY4 directly binds to W-box elements within the ZmCAT1 promoter in vivo and in vitro, thereby activating its transcription. Together, these findings define a previously uncharacterized ZmWRKY4-ZmCAT1 regulatory module that enhances antioxidant capacity and mitigates oxidative damage during Pb stress. This work provides new insights into the molecular mechanisms underlying heavy metal tolerance in maize and identifies a promising genetic target for developing Pb-resilient crop varieties.

Strawberry (Fragaria × ananassa) is a globally important economic crop valued for its nutritional and commercial significance. However, its growth is frequently challenged by various biotic and abiotic stresses. To enhance strawberry root development and resilience, we engineered a Trichoderma guizhouense NJAU4742 strain to overexpress the TgSWO gene, which encodes a plant cell-wall-loosening protein known to facilitate fungal penetration and colonization. Strawberry seedlings treated with the TgSWO-overexpressing T. guizhouense NJAU4742 strain (S-OE) exhibited significant improvements in shoot and root fresh weights, root surface area, and number of root tips, showing 1.37- to 2.00-fold increases compared with the strawberry seedlings inoculated with the wild-type T. guizhouense NJAU4742 (S-WT) and 2.00- to 3.44-fold increases compared with the uninoculated strawberry seedlings (S-CK). Field-emission scanning electron microscopy (SEM) of the S-OE roots revealed denser hyphal colonization. Transcriptome analysis of S-OE showed a decrease in genes related to defense and detoxification, while genes for cell-wall growth and hormone signaling increased, shifting focus from defense to growth. Metabolomic profiling identified cysteine as a key metabolite associated with induced growth, which was further validated through exogenous cysteine application experiments. This study highlights the potential of genetically enhanced Trichoderma for improving strawberry growth and provides new insights into root–microbe interactions and metabolite-mediated plant development.