Green manuring enhances multiple agroecosystem services functions, yet its impact on net greenhouse gas mitigation remains controversial, primarily due to a limited number of long-term experiments. To address these challenges, this study investigated the long-term effects of green manure (GM) rotations on 100-cm-depth soil organic carbon (SOC) sequestration, N2O emissions, and crop yields based on eight long-term experimental sites (7-16 years) in China's upland cropping systems combined with process-based modeling. The results demonstrated that green manuring significantly increased SOC concentration by 8.8 %-14.4 % (p < 0.001) across 0-100 cm soil profiles compared to fallow system, with annual SOC sequestration rates reaching 0.95-1.16 Mg C ha(-1) yr(-1) (p < 0.001). Notably, topsoil layer (0-40 cm) contributed 67.5 % of total profile SOC accumulation. Green manuring can replace approximately 40 % of synthetic fertilizers of N while maintaining long-term yield stability, though with potential trade-offs in elevated N2O emissions. The optimal net global warming potential (NGWP) reached -16.47 Mg CO2-eq ha(-1) yr(-1) under GM-based system with 30 % reduction in fertilizer N. Meanwhile, under the condition that GM substitution for fertilizer N achieved no yield reduction, the greenhouse gas intensity (GHGI) was optimized within the substitution rate range of 20 %-40 %. The results from process-based modeling demonstrate that substituting 30 % of N fertilizer with GM achieves optimal soil C sequestration while maintaining stable crop yields. These findings provide direct evidence that GM rotation increases C sequestration, addressing previous knowledge gaps in understanding the C sequestration and emission reduction effects of GM-based rotation.
Sunflower (Helianthus annuus L.), an important global oilseed crop, demonstrates remarkable tolerance to drought and salinity. Among transcription factors, dehydration-responsive element-binding (DREB) proteins are broadly distributed in plants and play pivotal roles in regulating abiotic stress responses. In this study, a total of 62 DREB genes were identified in sunflower and classified into five subgroups based on phylogenetic relationships, with 59 genes mapped to 16 chromosomes. Cis-acting element analysis indicated that HaDREB genes are primarily associated with stress responsiveness, phytohormone signaling, and light-regulated pathways, underscoring their functions in environmental adaptation and abiotic stress tolerance. Transcriptome analysis revealed that numerous HaDREB genes exhibited differential expression under drought, salinity, and cold stress, suggesting diverse and condition-specific regulatory roles. Furthermore, expression profiling across seed developmental stages demonstrated that most of the 31 detectable HaDREB genes were highly expressed during the middle and late stages of seed development, implying potential regulatory contributions to seed formation and maturation. Functional validation of HaDREB1D through overexpression in transgenic Arabidopsis thaliana confirmed its role in enhancing drought tolerance. Compared with wild-type plants, transgenic lines showed significantly higher survival rates and improved physiological performance after 14 days of drought treatment followed by 4 days of rewatering. This study provides the first experimental evidence that HaDREB1D contributes to drought stress tolerance in sunflower, establishing a foundation for future functional investigations of HaDREB genes in abiotic stress adaptation.
BACKGROUND:Cold stress affects animal husbandry severely. It has adverse effects on both production performance and animal health, thus directly reducing economic efficiency of animal production. Pigs are more susceptible to cold stress owing to absence of brown adipose tissue, an important organ for non-shivering thermogenesis. However, the knowledge on response to cold stress remains limited. To investigate the molecular mechanisms behind cold tolerance, we analyzed RNA expression profiles and regulatory networks in livers of pigs raised in a short-term low-temperature environment at transcriptome level. RESULTS:A total of 1,205 protein-coding genes, 122 lncRNAs and 52 miRNAs were involved in response to cold stress by RNA sequencing. Through integrated analysis of lncRNA and small RNA sequencing data, 533 mRNAs and two Kyoto Encyclopedia of Genes and Genomes pathways, PI3K-Akt and MAPK, were identified as critical for response to cold stress. Among the 533 mRNAs 47 were involved in PI3K-Akt or MAPK pathway and nine were shared by the both. Five out of the nine mRNAs such as EGFR, HGF, IGF1, PDGFD and EGFR2 belong to growth factors or the receptors. Based on the nine mRNAs and the differentially expressed lncRNAs and miRNAs ceRNA network was identified in which AKT was identified as the top hub gene, followed by PRKCA. Additionally, the ceRNA network was validated and PRKCA/ssc-miR-6782-3p/MSTRG.14353.2 was first constructed with molecular biology experiments. CONCLUSIONS:The study elucidates the critical genes, signaling pathways and the regulatory networks in regulating response to cold stress in porcine livers. The findings will contribute to fully revealing the mechanisms behind cold response and improving cold tolerance in pigs, which will benefit pig production.
Bacteria fruit blotch (BFB), a seed-borne bacterial disease caused by Acidovorax citrulli (A. citrulli), has led devastating losses on cucurbit industry, particularly in watermelon and melon production. In this study, two melon accessions, resistant line 1185 and susceptible line 1232, were crossed, and F2 population (88 and 225 individuals) was evaluated across two seasons (F2_Spring and F2_Autumn). Genetic analysis indicated that BFB resistance in melons exhibit the genetic characteristics of quantitative trait. Bulked segregant analysis sequencing (BSA‑seq) analysis, conducted using the index‑slid method and the Euclidean distance (ED) algorithm, identified six and five resistance‑associated chromosomal intervals located on chromosomes 8, 10 and 12, respectively. Within these intervals, MELO3C008984 and MELO3C035750 harboured nonsynonymous variants in their exons between two parental lines. Quantitative trait locus (QTL) mapping identified two QTLs qBFB-10.1 (1.89 Mb) and qBFB-10.2 (4.87 Mb) on chromosome 10 explaining between 4.57
IntroductionIsoflavones possess significant health benefits, including anti-inflammatory, anti-cancer, and antioxidant properties. Soybean (Glycine max (L.) Merr) is an effective natural source of isoflavones for humans. Thus, it is important to breed soybean varieties with enhanced isoflavone content and to elucidate the secondary metabolic pathways involved. Small auxin-up RNA (SAUR) genes constitute the largest family responsive to auxin, however, few studies have addressed their roles in soybean flavonoid metabolism.MethodsIn this study, flavonoid-targeted metabolites were measured in GmSAUR:GmSAUR transgenic soybeans. Chromatin immunoprecipitation sequencing (ChIP-seq) was performed to identify potential target genes regulated by GmSAUR. Additionally, RNA‑Seq was performed to identify downstream genes regulated by 35S:GmMYB176, including GmC4H, GmIF7MaT, GmCYP450 84A1‑like, and GmCYP450 84A1.ResultsThe transgenic soybeans exhibited higher contents of daidzin and genistin compared to controls. ChIP-seq revealed that GmSAUR binds to the promoter region of GmMYB176, thereby promoting the expression of downstream genes including cinnamate 4-hydroxylase (GmC4H), isoflavone 7-O-beta-glucoside 6′′-O-malonyltransferase (GmIF7MaT), cytochrome P450 84A1-like (GmCYP450 84A1-like), and cytochrome P450 84A1 (GmCYP450 84A1). This regulatory cascade ultimately led to increased accumulation of soybean isoflavones.DiscussionThese findings indicate that the GmSAUR gene facilitates soybean isoflavone biosynthesis by modulating the expression of GmMYB176, providing new insights into the genetic improvement of isoflavone content in soybean.
