Northeast Agricultural University

Sun D., Li S., Xiong W., Du X., Qiao K., Zhan A.

Harmful algal blooms (HABs) have emerged as a critical global environmental and ecological concern. Timely and accurate monitoring of the prevalent bloom-forming genera is crucial for HAB management. Conventional microscope-based methods are time-consuming, labor-intensive, and specialized expertise-dependent, often making them impractical for large-scale surveillance. Molecular methods, such as metabarcoding, provide efficient technical solutions; however, the lack of competent PCR primers and further field validation present obstacles to their wide use. Here, we successfully developed Aphanizomenon-specific primers and validated the application of environmental DNA (eDNA) metabarcoding for field-based monitoring of Aphanizomenon in 37 sites across lentic and lotic freshwater ecosystems in Beijing. The sensitivity and specificity tests of newly developed primers demonstrated high performance - comprehensive recovery of biodiversity in Aphanizomenon communities and high ratios (>95%) of Aphanizomenon sequences in datasets. We observed significant correlations between the sequence abundance derived from eDNA metabarcoding and the total cell density determined through microscopic identification across all the sampling sites, both in the spring (r = 0.8086, p < 0.0001) and summer (r = 0.7902, p < 0.0001), thus validating the utility of eDNA metabarcoding based on the newly developed primers for monitoring in the field. Further, we identified key environmental variables that were primary drivers responsible for the spatiotemporal distribution of Aphanizomenon abundance. These variables included temperature, total nitrogen, and dissolved oxygen in lentic ecosystems, and total phosphorus in lotic ecosystems. The method developed and validated here offers an accurate, efficient, and high-throughput tool for the monitoring of Aphanizomenon blooms in freshwater ecosystems.

Tuluhong M., Xiao Y., Zhang Q., Yang M., Wang B., Liu Q., Mu M., Kang N., Cui G.

Vicia amoena is renowned for its high protein content and nutritional value, making it significant in animal production and traditional Chinese medicine production. In July 2023, typical anthracnose symptoms were observed on V. amoena leaves in Suihua City (125°82'E, 46°22'N), Heilongjiang Province, China, affecting approximately 40% of the plants (a total of 200 plants were surveyed). Symptoms initially appeared as black-purple spots, gradually developing into larger, sometimes irregular reddish-brown lesions surrounded by yellow margins, with easily perforated necrotic lesions. Samples were collected from 20 leaves exhibiting distinct symptoms. Each leaf was cut into 5 x 5 mm sections at the junction of diseased and healthy tissues. The sections were surface sterilized: first, in 75% ethanol for 30 s, then in 1% NaClO for 2 mins, followed by three rinses with sterile distilled water. After air-drying, the samples were placed onto potato dextrose agar (PDA) plates and incubated at 26°C in the dark for 5 d. Subsequently, 15 isolates were obtained using the single-spore method, with nine (SYW1 to SYW9) showing similar morphological characteristics. On PDA, colonies appeared cottony and pale yellow from above, with a black-brown center on the reverse side. The conidia were hyaline, aseptate, subcylindrical with broadly rounded ends, measuring 13.8 to 18.6 μm in length and 4.8 to 6.4 μm in width (n = 50). Appressoria were subcylindrical or irregular, with a few lobes, brown to dark brown, and measured 9.2 to 12.3 μm in length and 5.1 to 7.2 μm in width (n = 50). Morphological analysis suggested a close resemblance to Colletotrichum aenigma (Weir et al. 2012). Genomic DNA was extracted from three representative isolates (SYW1 to SYW3) for molecular identification. The ITS, GAPDH, TUB2, CHS-1, and ACT genes were amplified and sequenced using primers previously described by Weir et al. (2012). Sequences were submitted to GenBank (ITS: PP949783 to PP949785; GAPDH: PP952315 to PP952317; TUB2: PP952318 to PP952320; CHS-1: PP952321 to PP952323; and ACT: PP952324 to PP952326). BLAST analysis revealed 100% identity with C. aenigma (GenBank accessions: OM663726, KY820889, MW387032, MN075525, and LC815246). Phylogenetic analysis placed the three isolates and C. aenigma in the same clade. Pathogenicity tests were conducted twice on 4-week-old V. amoena seedlings in a greenhouse. A conidial suspension of the SYW1 isolate (1 × 106 conidia/ml) was sprayed onto five pots, each containing four seedlings, while sterile distilled water was sprayed on the control pots. All plants were grown in a light incubator with a 12-h photoperiod, 100% relative humidity, and 26°C temperature. Two weeks post-inoculation, the inoculated seedlings showed reddish-brown spots and typical anthracnose lesions on inoculated leaves, with C. aenigma successfully reisolated from symptomatic tissues. To the best of our knowledge, this is the first report of C. aenigma causing anthracnose leaf spot on V. amoena in China. Although C. aenigma has previously been associated with anthracnose in crops such as grapes (Kim et al. 2021), mulberry (Zhu et al. 2023), and pecan (Zhao et al. 2024), its identification as a pathogen of V. amoena highlights a significant threat to this plant species in China. This finding underscores the urgent need for targeted disease management strategies to prevent further spread and damage, particularly in regions where V. amoena is economically or ecologically important.

Hu W., Deng C., Qin L., Liu P., Wang L., Wang X., Shi W., Aziz A., Li F., Cheng X., Wang A., Dai Z., Xiang X., Cui H.

ABSTRACT Potyviruses possess one positive-sense single-stranded RNA genome, mainly dependent on polyprotein processing as the expression strategy. The resulting polyproteins are proteolytically processed by three virus-encoded proteases into 11 or 12 mature proteins. One such factor, 6 kDa peptide 1 (6K1), is an understudied viral factor. Its function in viral infection remains largely mysterious. This study is to reveal part of its roles by using pepper veinal mottle virus (PVMV) as the model. Alanine substitution screening analysis revealed that 15 of 17 conserved residues across potyviral 6K1 sequences are essential for PVMV infection. However, 6K1 protein is less accumulated in virus-infected cells, although P3-6K1 and 6K1-CI junctions are efficiently processed by NIa-Pro for its release, indicating that 6K1 undergoes a self-degradation event. Mutating the cleavage site to prevent NIa-Pro processing abolishes viral infection, suggesting that the generation of 6K1 along with its degradation might be important for viral multiplication. We corroborated that cellular autophagy is engaged in 6K1’s degradation. Individual engineering of the 15 6K1 variants into PVMV allows their expression along with viral infection. Five of such variants, D30A, V32A, K34A, L36A, and L39A, significantly interfere with viral infection. The five residues are enclosed in a conserved lysine/arginine-rich motif; four of them appear crucial in engaging autophagy-mediated self-degradation. Based on these data, we envisaged a scenario which potyviral 6K1s interact with an unknown anti-viral component to be co-degraded by autophagy to promote viral infection. IMPORTANCE Potyvirus is the largest genus of plant-infecting RNA viruses, which encompasses socio-economically important virus species, such as Potato virus Y , Plum pox virus , and Soybean mosaic virus . Like all picorna-like viruses, potyviruses express their factors mainly via polyprotein processing. Theoretically, viral factors P3 through CP, including 6K1, should share an equivalent number of molecules. The 6K1 is small in size (~6 kDa) and conserved across potyviruses but less accumulated in virus-infected cells. This study demonstrates that cellular autophagy is engaged in the degradation of 6K1 to promote viral infection. In particular, we found a conserved lysine/arginine-rich motif in 6K1s across potyviruses that is engaged in this degradation event. This finding reveals one facet of a small protein that helps understand the pro-viral role of cellular autophagy in viral infection.

Peng M., Cai Z., Chen K., Yin C., Ao C., Ren H.

Air pollution is a critical global issue affecting sustainable development, and effectively addressing air pollution requires consumers to improve air quality through daily pro-environmental behaviors. This study aims to explore the influence mechanisms of multidimensional risk perception variables on consumers’ pro-environmental behaviors. It introduces risk effect, risk controllability, risk trust, and risk acceptability and incorporates multidimensional risk perception variables into the theory of planned behavior (TPB) model. The results of the structural equation model indicate that risk effect, risk trust, and risk acceptability of air pollution significantly influence pro-environmental behaviors through behavioral intentions. Moreover, the risk effect, risk trust, and risk acceptability of air pollution significantly influence consumers’ pro-environmental behaviors through the chain-mediating effect of attitudes and behavioral intentions. The risk controllability does not affect consumers’ behavioral intentions or pro-environmental behaviors. Through the integration of multidimensional risk perception and the validation of the behavioral intention–behavior gap, this study provides new perspectives for research related to consumer pro-environmental behavior. It also provides references for the government to communicate with consumers about risks, solve air pollution problems, and achieve sustainable development.

Li Q., Chang B., Huang G., Wang D., Gao Y., Fan Z., Sun H., Sui X.

Protein constitutes the primary nutrient in soy, and its modifications are intricately linked to the properties of the soy milk powder. This study employed six main commercial enzymes (bromelain, neutrase, papain, trypsin, flavourzyme, and alcalase) to investigate the impact of enzymatic hydrolysis on the structural and functional properties of soy protein isolate (SPI), as well as its influence on the physicochemical properties of soy milk powder. The findings indicated that each of enzymes exhibits distinct specificity, with the degree of hydrolysis following the order: alcalase > flavourzyme > papain > bromelain > neutrase > trypsin. Enzymatic hydrolysis facilitates the unfolding of SPI, leading to the exposure of chromogenic fluorophores and hydrophobic amino acid residues, which in turn promotes an increase in free sulfhydryl content. Concurrently, this process induces the transformation of α-helix and β-sheet into β-turn and random coil. The enzyme modification enhances the solubility, emulsification, and foaming activities of SPI and significantly augment its antioxidant properties (p < 0.05). However, this enzymatic treatment adversely affects the stability of its emulsification and foaming properties. Subsequent to enzymatic hydrolysis, soy milk powder demonstrated a reduction in particle size and an improvement in solubility, which significantly enhanced its flavor profile. In summary, alcalase offers substantial advantages in augmenting the functional properties of SPI and increasing the solubility of soy milk powder. However, this process adversely affects the flavor profile of soy milk powder, a consequence attributed to the broad hydrolysis specificity of alcalase.

Zheng Y., Zhou W., Cheng K., Chen Z.

Ionic liquids based on imidazolium cations have attracted attention due to their high safety and exceptional ionic conductivity. However, imidazole-based ionic liquids exhibit poor electrochemical stability due to the strong reactivity of hydrogen atoms at the C-2 position of imidazole cations. In this work, an ionic liquid 1-butyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide ([C4C1mim][TFSA]), characterized by a methyl-substituted C-2 position and a butyl chain, was investigated in various Li+ environments created by different lithium salt concentrations and fluoroethylene carbonate (FEC) additives. Both optimal Li+ concentrations and the addition of reasonable FEC enable the improvement of ionic conductivity to 3.32 mS cm−1 at 25 °C and a maximum electrochemical window of 5.21 V. The ionic liquid electrolyte Li[TFSA]-[C4C1mim][TFSA] at a molar ratio of 2:8 with 5 wt% FEC addition demonstrates excellent thermal stability. The corresponding Li/LiFePO4 cell exhibits a mitigated polarization growth (increasing from 0.12 V to 0.25 V over 10 cycles) with a high initial discharge capacity of 169.3 mAh g−1.

Jiang J., Wang C., Chen A., Xie F., Chen Y.

Drought stress is the most common threat to plant growth, while physiological integration can significantly enhance the drought tolerance of clonal plants, making it essential to research the behavior of clones under drought conditions and explore the potential applications of clonal plants. This study applied polyethylene-glycol-6000-induced stress to proximal, middle and distal clonal ramets of Kentucky bluegrass (Poa pratensis L.) and used an isotope labeling technique to evaluate the water physiological integration and photosynthetic capacity. When the proximal ramet was subjected to drought stress treatment, the decrease in 2H isotopes in the roots from 4 h to 6 h was significantly smaller than the increase in 2H isotopes in their own leaves. Additionally, the reductions in δ2H values of middle and distal ramets roots were 4.14 and 2.6 times greater, respectively, than the increases in their respective leaf δ2H values. The results indicate that under drought stress, water physiological integration was observed among different clonal ramets. In addition, drought stress inhibits the photosynthetic-related indicators in clonal ramets, with varying degrees of response and trends in photosynthetic characteristics among different clonal ramets. The proximal ramet treatment group, treated with polyethylene glycol 6000, was most affected by drought stress, while the distal ramet treatment group was least affected. The proximal ramet treatment group, treated with polyethylene glycol 6000, showed a decrease in water use efficiency after 6 h of drought treatment, while the other groups exhibited some increase. This indicates differences in water utilization and regulation among the different clonal ramets under drought stress. This study holds significant theoretical importance for exploring the characteristics of physiological integration and the photosynthetic mechanisms of Kentucky bluegrass clones under drought stress.

Anwar A., Faiz M.A., Badar I.H., Jaspal M.H., Hou J.

Fermented milk products, such as yogurt, undergo significant changes in their physicochemical, sensory, textural, and rheological properties based on fermentation time and storage. This study investigated how different fermentation times (4, 5, 6, 7, and 8 h) and storage durations (1, 7, 14, and 21 days) influenced the characteristics of probiotic yogurt made from sheep milk, cow milk, and a blend of both. Using 2% of each of Lactobacillus rhamnosus GG, Lactobacillus bulgaricus, and Streptococcus thermophilus, fermentation was conducted at 40 °C. The results demonstrated that fermentation time and storage had a significant impact on pH, acidity, total bacterial count (TBC), water-holding capacity (WHC), syneresis, and sensory attributes. Probiotic yogurt made from sheep milk, when fermented for 6 h and stored for 1 day, exhibited the highest acidity (109.42 °T), total bacterial count (TBC) (592.41 × 106 cfu/g), water-holding capacity (WHC) (658.42 g/kg), and sensory score (8.62), with a final pH of 4.25. In contrast, cow milk yogurt, fermented for 5 h and stored for 14 days, had the lowest acidity (81.76 °T), TBC (305.75 × 106 cfu/g), and sensory score (6.24), with a pH of 4.44. The blended yogurt, fermented for 6–7 h and stored for 1 day, showed intermediate values, with an acidity of 89.55 °T, TBC of 284.33 × 106 cfu/g, and a sensory score of 7.24. Syneresis varied from 18.06 to 19.67, with cow milk yogurt, fermented for 6 h and stored for 1 day, exhibiting the highest level. These findings highlight the impact of fermentation time and storage on yogurt quality, with optimized conditions enhancing texture, stability, and sensory appeal. These variations in yogurt properties highlight the critical role of fermentation time and storage conditions in defining texture and stability. Notably, the optimal fermentation times for achieving desirable physicochemical and sensory properties were found to be 6 h for sheep milk yogurt, 5 h for cow milk yogurt, and 6–7 h for the blend. The findings emphasize the importance of milk composition and fermentation conditions in optimizing probiotic yogurt quality. Furthermore, the study underscores the potential of sheep milk in producing yogurt with superior sensory and textural characteristics, offering promising opportunities for the development of high-quality functional dairy products.

Trinh Thi V.H., Zhou W.

Climate warming poses a significant threat to China’s national food security as grain production encounters the daunting challenge of climate change. Thus, promoting the shift of agriculture toward climate-smart practices has become an inevitable choice. This study investigated climate-smart agriculture (CSA) practices using agricultural and environmental indicators that affect the technical efficiency of grain farming in Northeast China. The study employs the stochastic frontier analysis approach to estimate the efficiency of the production function and highlight the significant factors that affect efficiency. The entropy weight method was also used to analyze the climate-smart agricultural development index (CSA-DI) and climate-smart balanced development index (CSA-BDI) in Northeast China. The provincial panel data from 1980 to 2017 revealed an increasing trend for the CSA-DI and CSA-BDI. Although the region has achieved initial results in systematicity and coordination, there is still room for improvement in food security and climate change adaptation. Based on these results, this study proposes policy recommendations for CSA technologies and the promotion of comprehensive projects to endorse climate-smart agriculture for regional shared benefits and responsibilities.

Wang J., Wang C., Xu Y., Wang C., Tang H.

The delayed decomposition of rice straw in Northeast China’s cold regions (winter temperatures < −20 °C) due to insufficient accumulated temperature requires innovative solutions. This study developed a synergistic approach combining microbial decomposition with mechanical burial. Pre-experiments identified optimal parameters for the liquid decomposing agent (100 mg/mL concentration, 6 g/m application rate). A novel combined machine was engineered with adjustable parameters: knife roller speed (200–300 r/min), burial depth (15–25 cm), and ground clearance (80–120 mm). Field trials demonstrated a 91.3% straw return rate under optimized settings (220 r/min, 100 mm clearance, 1.7 m/s speed), representing a 28.5% improvement over conventional methods. Spring burial enhanced straw decomposition to 83.6% within 60 days (vs. 67.2% in autumn), significantly increasing soil organic matter and available nitrogen. The integrated technology achieved 1.5 hm2/h operational efficiency, meeting regional agronomic demands. This study provides a replicable model for cold-region straw utilization, aligning with carbon sequestration goals in black soil conservation.

Wang S., Liu M., Di A., Jiang X., Wu J., Zhang J., Liu X., Bai C., Su G., Song L., Li G., Liu Z., Yang L.

Superovulation and embryo transfer are key technologies to improve the reproductive ability of female animals and enhance the efficiency of livestock production. However, poor-quality oocytes or abnormal fluctuations of hormone levels caused by superovulation affect the embryonic development environment, which may lead to a significant decline in the number and quality of transferable embryos, thus reducing the efficiency of superovulation. In this study, nicotinamide adenine dinucleotide (NAD+) was injected into Huaxi cows during the superovulation period to observe the proliferation and apoptosis of transplanted embryos. We examined the proliferation, apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential of cumulus cells and oocytes directly treated with NAD+ and investigated the potential mechanism of NAD+ to improve the superovulation efficiency by serum metabolomics and single-cell RNA sequencing. The results show that the addition of NAD+ significantly increased the quantity and quality of transferable embryos after superovulation. Differential metabolites during estrus synchronization and embryo flushing are enriched in glycerophospholipid metabolic pathways, suggesting that NAD+ can regulate lipid metabolic pathways. We found that NAD+ optimized the secretion levels of the steroid hormone estradiol (E2) and progesterone (P4) during superovulation by regulating the activity of cumulus cells. In oocytes, we found that NAD+ can inhibit apoptosis, scavenge ROS, and enhance mitochondrial function, thereby promoting oocyte maturation and enhancing embryo developmental potential. In conclusion, NAD+ significantly improved the superovulation ability of Huaxi cattle and provides an effective way for animal husbandry to improve the yield of high-quality embryos.

Zhang M., Zhu M., Lang H., Wang W., Li X., Jiang M.

Orphan genes (OGs) are genes that have no significant sequence similarity with known genes from other species or lineages. Identifying and characterizing OGs have become more feasible with the increasing availability of plant transcriptomes and genome sequences. OGs play important roles in response to both biotic and abiotic stresses, contributing to biological functions and lineage-specific traits. This study aimed to identify and characterize OGs in Coriandrum sativum (coriander) using the BLAST method. A total of 941 C. sativum OGs (CsOGs), 1298 Apiaceae-specific genes (ASGs), and 38,508 evolutionarily conserved genes (ECGs) were identified through comparative genomics. Genic feature analyses revealed that CsOGs and ASGs, although part of different gene sets, had shorter gene lengths, a lower proportion of multi-exon genes, and higher GC content than ECGs. OGs were distributed across all 11 chromosomes, with the highest proportion of CsOGs and ASGs found on chromosome A11. RNA-Seq analysis revealed 71 CsOGs uniquely expressed in four different tissues, 61 CsOGs specifically expressed across three growth stages, and five CsOGs with specific expression patterns in different tissues and growth stages. Notably, as determined via qRT-PCR analysis, these five CsOGs presented general or specific expression patterns under normal conditions, but their expression significantly increased after exposure to cold stress, suggesting that they may play a critical role in cold stress response. This study comprehensively identified, characterized, and analyzed the expression of OGs within coriander, which provides a foundation for further research on the functions of coriander OGs in influencing species-specific trait formation and stress response.

Zhu B., Xu T., Zhang X., Zhang C., Feng G.

Abandoned production and monitoring wells in depleted oil and gas fields can readily serve as primary leakage pathways for stored CO2. The temperature, pressure conditions around the wellbore bottom, and CO2 concentration influence the phase behavior of CO2 during leakage. This study establishes a 3D wellbore–reservoir coupled model using CO2 injection data from 1 December 2009, in the DAS area, eastern Cranfield oilfield, Mississippi, USA, to analyze the dynamic evolution of CO2 leakage along wellbores. Simulations are conducted using the collaboration of ECO2M and ECO2N v2.0 modules. The study examines leakage regimes under varying distances from the injection well and different reservoir temperatures. The results indicate that CO2 phase changes occur primarily in wells near the injection point or under high-pressure and high CO2 saturation conditions, usually with a short leakage period due to ice formation at the wellhead. In areas with low CO2 saturation, prolonged leakage periods lead to significant pressure drops at the bottom, as well as the temperature as a result of the Joule–Thomson effect. Lower reservoir temperatures facilitate smoother and more gradual leakage. These findings provide a theoretical foundation for ensuring the safe implementation of CCUS projects and offer insights into the mechanical explanation of CO2 geyser phenomena.

Meng Q., Liu J., Li F., Chen P., Xu J., Li Y., Nie T., Han Y.

This study addresses the challenge of estimating reference crop evapotranspiration (ETO) in Xizang Plateau irrigation districts with limited meteorological data by proposing a coupled LASSO-BP model that integrates LASSO regression with a BP neural network. The model was applied to three irrigation districts: Moda (MD), Jiangbei (JB), and Manla (ML). Using ETO values calculated by the FAO-56 Penman–Monteith (FAO-56PM) model as a benchmark, the performance and applicability of the LASSO-BP model were assessed. Short-term ETO predictions for the three districts were also conducted using the mean-generating function optimal subset regression algorithm. The results revealed significant multicollinearity among six meteorological factors (maximum temperature, minimum temperature, average temperature, average relative humidity, sunshine duration, and average wind speed), as identified through tolerance, variance inflation factor (VIF), and eigenvalue analysis. The LASSO-BP model effectively captured the interannual variation of ETO, accurately identifying peaks and troughs, with trends closely aligned with the FAO-56PM model. The model demonstrated strong performance across all three districts, with evaluation metrics showing MAE, RMSE, NSE, and R2 values ranging from 4.26 to 9.48 mm·a−1, 5.91 to 11.78 mm·a−1, 0.92 to 0.96, and 0.82 to 0.94, respectively. Prediction results indicated a statistically insignificant declining trend in annual ETO across the three districts over the study period. Overall, the LASSO-BP model is a reliable and accurate tool for estimating ETO in Xizang Plateau irrigation districts with limited meteorological data.

Jiao Z., Feng Z., Zhao S., Wang Y., Feng M., Chen Q., Kong B., Liu H.

Peanut protein is a byproduct of peanut oil extraction with limited applications within the food sector due to its low solubility and emulsifying properties. This study investigated the influences and mechanisms of high-intensity ultrasound (HIU, 200~600 W) and pH-shifting (pH 12), either individually or jointly, on the structure, solubility, and emulsifying properties of PP. Results indicated that the solubility of PP significantly increased after the combined treatment, particularly when the HIU power was 300 W (p < 0.05). Accordingly, emulsions prepared from it exhibited highest storage stability. Structural analysis indicated that the increased PP solubility (9.95% to 54.37%, p < 0.05) is mainly attributed to the structural changes that occur during protein unfolding, resulting in the uncovering of hydrophobic groups (7181.43 to 14,083.00, p < 0.05) and the reduction of α-helices (24.43% to 18.17%, p < 0.05). Moreover, confocal laser scanning microscopy of the emulsions revealed that the combination-treated PP resulted in smaller protein particle sizes (50.09 μm to 15.68 μm, p < 0.05), tighter adsorption on the oil–water interface, and a denser and more stable interfacial film compared to the native and the individual treatment, thereby enhancing the stability of the system. A rheological analysis confirmed that the combined treatment improved the interfacial properties of the protein, which was advantageous for emulsion stability. In conclusion, HIU combined with pH12-shifting can appreciably improve the solubility and emulsifying properties of PP to broaden its application prospects.