Flowering is crucial for reproductive success in flowering plant. The CCT domain-containing genes widely participate in the regulation of flowering process in various plant species. So far, the CCT family in common wheat is largely unknown. Here, we characterized the structure, organization, molecular evolution and expression of the CCT genes in Aegilops tauschii, which is the D genome donor of hexaploid wheat. Twenty-six CCT genes (AetCCT) were identified from the full genome of A. tauschii and these genes were distributed on all 7 chromosomes. Phylogenetic analysis classified these AetCCT genes into 10 subgroups. Thirteen AetCCT members in group A, C, H and G achieved rapid evolution based on evolutionary rate analysis. The AetCCT genes respond to different exogenous hormones and abiotic treatments, the expression of AetCCT4, 7, 8, 11, 12, 16, 17, 19, 21 and 22 showed a significant 24 h rhythm. This study may provide a reference for common wheat's evolution, domestication and evolvement rules, and also help us to understand the ecological adaptability of A. tauschii.

The integration of manure and straw substantially affects soil organic carbon (SOC) dynamics, transformation, and long-term stabilization in agricultural systems. Dissolved organic carbon (DOC), particulate organic carbon (POC), and mineral-associated organic carbon (MOC) are the three main components of the SOC pool, each influencing soil carbon dynamics and nutrient cycling. Current research gaps remain regarding how combined fertilization practices affect the inputs of plant-originated and microbe-derived carbon into SOC pools and stability mechanisms. Our investigation measured SOC fractions (DOC, POC, MOC), SOC mineralization rate (SCMR), microbial necromass carbon, lignin phenols, enzyme activities, and microbial phospholipid fatty acids (PLFAs) over a long-term (17 years) field experiment with four treatments: mineral fertilization alone (CF), manure-mineral combination (CM), straw-mineral application (CS), and integrated manure-straw-mineral treatment (CMS). The CMS treatment exhibited notably elevated levels of POC (7.42 g kg⁻¹), MOC (10.7 g kg⁻¹), and DOC (0.108 g kg⁻¹), as well as a lower SCMR value (1.85%), compared with other fertilization treatments. Additionally, the CMS treatment stimulated the buildup of both bacterial and fungal necromass while enhancing the concentrations of ligneous biomarkers (vanillin, syringyl, and cinnamic derivatives), which correlated strongly with the elevated contents of fungal and bacterial PLFAs and heightened activity of carbon-processing enzymes (α-glucosidase, polyphenol oxidase, cellobiohydrolase, peroxidase, N-acetyl-β-D-glucosidase). Furthermore, fungal and bacterial microbial necromass carbon, together with lignin phenols, significantly contributed to shaping the composition of SOC. Through random forest analysis, we identified that the contents of bacterial and fungal necromass carbon were the key factors influencing DOC and MOC. The concentrations of syringyl phenol and cinnamyl phenols, and the syringyl-to-cinnamyl phenols ratio were the primary determinants for POC, while the fungal-to-bacterial necromass carbon ratio, as well as the concentrations of vanillyl, syringyl, and cinnamyl phenols, played a critical role in SCMR. In conclusion, the manure combined with straw incorporation not only promoted microbial growth and enzyme activity but also enhanced plant- and microbial-derived carbon inputs. Consequently, this led to an increase in the contents and stability of SOC fractions (DOC, POC, and MOC). These results suggest that manure combined with straw is a viable strategy for soil fertility due to its improvement in SOC sequestration and stability.

Conservation tillage and fertilization are widely adopted in agricultural systems to enhance soil fertility and influence fungal communities, thereby improving agroecosystems. However, the effects of no-tillage combined with manure on grain yield, nitrogen use efficiency (NUE), soil fertility, and rhizosphere fungal communities remain poorly understood, particularly in rainfed wheat fields on the Loess Plateau. A 15-year field experiment was conducted at the Niujiawa Experimental Farm of the Cotton Research Institute, Shanxi Agricultural University. Five treatments were assessed: conventional tillage without fertilizer (C), no-tillage with chemical fertilizer (NT), no-tillage with chemical fertilizer and manure (NTM), conventional tillage with chemical fertilizer (T), and conventional tillage with chemical fertilizer and manure (TM). The results demonstrated that the NTM treatment significantly increased grain yield by 124.95%, NT by 65.88%, TM by 68.97%, and T by 41.75%, compared to the C treatment (p < 0.05). NUE in the NTM treatment was improved by 58.73%–200.59%. Compared with the C treatment, NTM significantly enhanced soil nutrients, including organic matter (OM) by 70.68%, total nitrogen (TN) by 8.81%, total phosphorus (TP) by 211.53%, available nitrogen (AN) by 90.00%, available phosphorus (AP) by 769.12%, and available potassium (AK) by 89.01%. Additionally, the NTM treatment altered the rhizosphere fungal community of winter wheat, with Ascomycota (81.36%–90.24%) being the dominant phylum, followed by Mucoromycota (5.40%–12.83%) and Basidiomycota (1.50%–8.53%). At the genus level, NTM significantly increased the abundance of Mortierella and Dendrostilbella. An α-diversity analysis revealed that the richness and diversity of soil fungi were highest under NTM. The unweighted pair-group method with arithmetic mean (UPGMA) and principal coordinates analysis (PCoA) based on Bray-Curtis distances indicated that NTM formed a distinct fungal community with the highest phylogenetic diversity, which differed significantly from other treatments. Redundancy analysis (RDA) demonstrated that soil chemical properties variably influenced fungal community dynamics, with higher abundances of Ascomycota and Zoopagomycota positively correlated with OM, AN, AP, TP, and AK. Correlation analysis showed that wheat yield and NUE were positively correlated with Mortierella and Dendrostilbella, and negatively correlated with Fusarium, Chaetomium, and Alternaria. In conclusion, no-tillage with manure not only enhanced soil fertility but also enhanced soil fungal community structure, leading to greater wheat yield and NUE. These findings provide guidance for agricultural practices in rainfed wheat fields of the Loess Plateau.

Straw incorporation and manure are recognized as a sustainable farming practice to enhance soil fertility and improve crop yields. However, the effects of straw incorporation in combination with manure on productivity, soil nutrient status, N use efficiency (NUE), and the bacterial community are not well understood in wheat–summer maize rotation systems in the southern Shanxi Province. The five treatments were (1) CK, no fertilization; (2) NP, inorganic N and P fertilizers; (3) NPM, mineral N and P fertilizers plus chicken manure; (4) SNP, mineral N and P fertilizers plus maize straw; and (5) SNPM, mineral N and P fertilizers plus maize straw and chicken manure. The results showed that NP, NPM, SNP, and SNPM significantly increased wheat yields by 56.19%, 76.89%, 111.08%, and 114.30%, compared with CK, respectively. Nitrogen agronomic efficiency (AE_N), partial factor productivity (PEP_N), apparent recovery efficiency (Apparent RE_N), and accumulated recovery efficiency (Accumulated RE_N) increased by 103.36%, 37.19%, 76.39%, and 30.90% in the SNPM treatment, compared with NP. Straw incorporation and manure significantly improved soil fertility. Proteobacteria, Acidobacteriota, Actinobacteriota, Chloroflex, Bacteroidota, Planctomycetota, Gemmatimonadota, Armatimonadota, Firmicutes, Methylomirabilota, and Myxococcota were the predominant bacterial phyla. Compared with NP, straw incorporation and manure (NPM, SNP, and SNPM) decreased diversities (richness index, Chao1 index, and Shannon index). Principal coordinates (PCoA) and cluster analyses demonstrated that manure treatments (NPM and SNPM) significantly optimized bacterial community structure. Pearson’s correlation analysis demonstrated that organic matter, total phosphorus, available nitrogen, available phosphorus, and available potassium had significant positive correlations with Halanaerobiaeota but significant negative positive correlations with Chloroflexi, Entotheonellaeota, and Myxococcota. Wheat yields, AE_N, PEP_N, Apparent RE_N, and Accumulated RE_N were primarily and significantly negatively associated with Cyanobacteria. Straw incorporation in combination with manure significantly optimized bacterial community structure, wheat yields, and N use efficiency through improving soil fertility. Collectively, straw incorporation in combination with manure is a promising practice for sustainable development.

How different fertilization practices modify soil organic carbon (SOC) sequestration is still unclear. Our study aimed to evaluate the changes in SOC stocks and their physical fractions after 10 years of organic and inorganic fertilization. Five treatments were established under a wheat-maize system in Northern China: control (CK), chemical fertilizer (F), straw plus chemical fertilizer (SF), manure plus chemical fertilizer (MF), and straw and manure plus chemical fertilizer (SMF). The results showed that the SOC sequestration rate at 0–20 cm depth decreased in the following order: SMF (1.36 Mg C/ha/yr) > MF (1.13 Mg C/ha/yr) > SF (0.72 C/ha/yr) > F (0.15 Mg C/ha/yr) > CK (−0.25 Mg C/ha/yr). The values indicated that straw returning and manure application were important measures to achieve the “4 per 1000” target, and the application of manure was a more effective strategy. The high input of chemical fertilizer only maintained the initial SOC level and was not a powerful C-farming practice. A minimum input of 4.93 Mg C/ha/yr was required to keep the initial SOC storage. The SOC associated with small macroaggregate (0.25–2 mm) was the most sensitive indicator for the changes of bulk SOC. In addition, the accumulation of SOC under SMF, MF, and SF treatments mainly occurred in the occluded particulate organic C (oPOC) in small macroaggregates, indicating that the physical protection of macroaggregates played a predominant role in SOC sequestration. The SMF, MF, and SF treatments also displayed higher mineral organic C (mSOC) in soil aggregates than the CK and F treatments. A transformation of oPOC towards the mSOC fraction indicated that exogenous C further shifted into stable C pools under the physical protection of soil aggregates. In conclusion, these findings confirmed the important role of straw returning and manure application in SOC accumulation and stabilization, highlighting that a combination strategy of straw + manure + chemical fertilizer had the best effect.