Annals of Agricultural Science最新文献

Probiotic lactic acid bacteria (LAB) have garnered substantial attention for their potential health benefits, particularly in supporting the balance of gut microbiota. This study sought to assess LAB isolates from honeybees stomach as potential probiotics by evaluating their tolerance to acid and bile, autoaggregation, hydrophobicity, co-aggregation with pathogens, antioxidant activity, haemolysis, exopolysaccharide (EPS) production, in vitro cell adherence, and their performance in milk-based fermented products. The LAB isolates exhibited impressive resilience to gastric acid, surviving exposure to simulated gastric juice at pH 2 after 2 h of incubation. Autoaggregation and hydrophobicity, crucial for probiotic adhesion to intestinal epithelial cells, were observed in several LAB isolates. Notably, Ehb3, Ehb5, and Ehb8 displayed the highest values, indicating their potential for effective intestinal adhesion. The antioxidant activities of intracellular and cell-free lactic acid bacteria strain extracts were evaluated using DPPH (2,2-Diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radical scavenging tests. Ehb3 and Ehb5 demonstrated outstanding antioxidant capabilities, suggesting their potential for enhancing the shelf life and health benefits of probiotic products. These lactic acid bacteria strains were also proficient in fermenting milk, maintaining viability above the technological requirements for probiotic products during storage. Finally, lactic acid bacteria isolate from honey bee stomach exhibit promising characteristics that make them suitable candidates for potential probiotics with health benefits.

Phosphorus (P) fertilizer is a significant cost in crop production. Understanding the mechanisms behind P fertilizer–soil–crop interactions can enhance phosphorus use efficiency (PUE) and increasing yield. We conducted a rice cultivation bucket experiment in red soil (pH = 5.9) and lime concretion black soil (pH = 7.8) and applied single superphosphate (SSP), calcium magnesium phosphate (CMP), diammonium phosphate (DAP), triple superphosphate (TSP), ammonium polyphosphate (APP), and a control group (CK, no P fertilizer). We analyzed rice P uptake and utilization patterns, evaluated the impact of varying P fertilizer formulations on rice root morphology, yield, and PUE, and investigated changes in soil P pools. In red soil, the APP treatment produced the greatest total root length, rice yield, PUE and increased soil Olsen-P, NaHCO₃-Pi at anthesis. In lime concretion black soil, the TSP and APP treatments had the highest rice yields and increased Olsen-P, H₂O-P, NaHCO₃-Pi at anthesis. Moreover, the TSP treatment had the greatest total root length and root surface area at anthesis and the APP treatment had the largest PUE. Random forest regression analysis revealed that residual-P and Olsen-P significantly impacted rice yield in red soil and lime concretion black soil, respectively. We recommend using APP in red soil and TSP and APP in lime concretion black soil for rice cultivation to optimize soil P pool characteristics and root morphology for nutrient uptake, ultimately leading to the highest yields and PUE.

The harvest moisture content (MC) of maize (Zea mays L.) is an important factor affecting industrial processing and harvest quality. However, higher MC levels may escalate drying expenses during production. While augmented plant density has shown potential to enhance maize yield, limited information exists regarding its impact on plant density and MC interaction. This study amassed four year of field trial data from four primary maize ecological areas in China (Longitude: 89°E to 125°E, Latitude: 35°N to 44°N) to examine the relationship between plant density and MC of maize. Our analysis revealed that increasing plant density exerted an effect on the MC of maize. This effect stemmed from a combination of uncertain grain development and premature plant senescence due to overcrowding. We categorized the relationship between plant density and MC into six types: NC-Type (No-changing), I-Type (ever-increasing), L-Type (ever-lessening), V-Type (like the valley), P-Type (like the peak), and W-Type (like a wave). On average, a variation approximately 0.053 % in MC was observed when the plant population changed by 1000 plants/ha. Moreover, different maize varieties contributed to a more substantial variation in MC. Despite the negligible impact of MC variation caused by plant density on grain quality, subsequent harvest management, and industrial production of maize, there was a significant enhancement in maize yield with increased plant density. Thus, increasing plant density presents an opportunity to boost maize output without compromising quality or grain moisture levels.

Both increased plant density and wide seedling strip planting (WSP) can improve wheat grain yield. However, whether and how greater gains in grain yield can be achieved by combining WSP with an increased plant density is unclear. In this study, two winter wheat cultivars were subjected to three plant densities (lower, normal, and higher) and two planting patterns (conventional planting [CP] and WSP). The effects of plant density, planting pattern, and their combination on the solar radiation interception and conversion, biomass accumulation, harvest index, and grain yield were investigated. In response to an increase in plant density from lower to higher and a shift from CP to WSP and their combination, grain yield increased by 15.43 %, 10.85 % and 27.62 % for cultivar Taimai198, and by 13.13 %, 8.31 % and 22.41 % for Shannong30, respectively. The larger increases in grain yield were mainly ascribed to enhanced dry matter production, in particular after anthesis with no variation or a slight decline in the harvest index. The higher plant density was the dominant driver of the enhanced radiation interception, whereas WSP was mainly responsible for ameliorating the reduction in radiation use efficiency (RUE) caused by the higher plant density. The combined effects of these two management practices in increasing grain yield were much greater than the independent effects of a shift from CP to WSP or an increase in plant density. Optimizing the planting method may thus be a promising option for further improving grain yield of a densely planted wheat population by increasing the RUE.

Maize (Zea mays L.), as a cornerstone crop, is integral to both livestock feed and human nutrition. However, the effects of long-term manure application on maize yield, micronutrient levels, and nutritional quality under a maize-soybean rotation system have not been fully elucidated. This study investigates the impact of long-term manure application on maize yield, the micronutrients content of grains, and grain nutritional quality in a maize-soybean rotation. Our results indicate that consistent manure application significantly enhances maize yield. Compared to the long-term chemical fertilizers only, the addition of manure increased the Fe, Mn, Cu, and Zn concentrations of the grains. In addition, the highest grain protein concentration was observed when treated with manure. Concentrations of protein fractions such as globulins, gliadins, and glutenins were found to be higher with a low manure application (13.5 t ha⁻¹) compared to high manure application (27 t ha⁻¹). The optimum increments in essential amino acids (EAA) and the ratios of essential to nonessential amino acids (EAA/NAA) was observed under low manure addition treatment. Collectively, incorporating manure into a long-term maize-soybean crop rotation not only escalates yields but also critically enhances the nutritional profile of maize grains through an increase in micronutrients and by promoting balance of proteins and amino acids within the grain. In the long run, low manure addition is more conducive to improving the nutritional quality of grains under crop rotation systems.

The influence of 2-chloro-6-(trichloromethyl) pyridine (CP) on growth, nitrogen (N) absorption and utilization, and yield of rice were examined to offer a technical reference for enhancing rice yield and efficient production under nitrogen limitation in cold regions. In this experiment, Japonica rice was planted with six treatments: 115 kg·ha⁻¹ N (local conventional application, N115), application of N reduced by 20 % (N92), N reduced by 20 % + 900 g ha⁻¹ CP (N92 + CP), N reduced by 30 % (N80.5), N reduced by 30 % + 900 g ha⁻¹ CP (N80.5 + CP), and no-N fertilizer (N0) were used to study the effects of CP on factors relating to yield. In 2022, compared with N92, N92 + CP significantly increased soil available N content (SAN), N uptake (NU), and N fertilizer utilization efficiency (NUE). These factors contributed to an increase in the leaf area index of all leaves at jointing and the leaf area index of the top three leaves at heading. In 2021, the tiller number per hill, dry matter accumulation (DMA) from jointing to heading, DMA from heading to maturity (DMAH), crop growth rate (CGR) from jointing to heading, and CGR from heading to maturity (CGRH) were increased and thus contributed to an increase in total yield. Compared with N80.5, N80.5 + CP significantly increased tiller number per hill, SAN, and NUE in 2022, while the DMAH, CGRH, and yield were increased in 2021 and 2022. This study indicates that CP can maintain rice yield by increasing NU and NUE even under reduced N rates.

Qinghai−Tibetan Plateau (QTP) is the largest contiguous grazing area in the world, while its soil has a low soil selenium (Se) content, an essential rare element for human health. Grazing and Se addition are two common management practices in the regional grasslands, but their interactions with the vegetation growth of alpine meadows in the QTP remain largely unknown. Here, we conducted a two−year field experiment (2017 and 2018) to explore the effects of grazing [two stocking rates (0 and 6 sheep months ha⁻¹)] and Se addition [six Se addition levels (0, 5, 10, 20, 40 and 80 g ha⁻¹)] on above−ground biomass (AGB), below−ground biomass (BGB), root−to−shoot ratio (R/S), species richness and Shannon−Wiener's diversity index of an alpine meadow at the Maqu county in the Eastern QTP. The results indicate that AGB peaked at a Se addition rate of 21 g ha⁻¹ combined with no grazing (i.e., exclosure) and at a rate of 20 g ha⁻¹ Se addition with a stocking rate of 6 sheep months ha⁻¹; BGB was highest under a Se addition of 23.5 g ha⁻¹ (under exclosure) and 23 g ha⁻¹ (under grazing). After Se addition, the species richness and Shannon−Wiener index of the alpine meadow under the grazing treatment were significantly lower than those in the exclosure treatment, which was mainly driven by the reduction of sedges and forbs. The structural equation model showed that grazing reduced the biomass of sedge, gramineae, and forbs, while Se addition increased the soil available nitrogen and phosphorus content and promoted the growth of sedge, gramineae, and forbs. Our results suggested that moderate grazing combined with Se addition is a suitable management method for maintaining alpine meadow productivity.

There is a constant search for safer, eco-friendly and effective insect control agent alternatives of natural origin due to concerns in human health, ecology and development of insect resistance to conventional chemical insecticides. Accordingly, a fumigant molecule, isosecotanapartholide (ISTP) from Artemisia vulgaris L., has been isolated and characterized following laboratory bioassays against stored grain insect pests. Physicochemical and spectroscopic analyses correlated with literature data to yield the structure of ISTP, a volatile organic compound. The isolated organic compound is highly toxic to adults of Sitophilus oryzae (L.), Tribolium castaneum (Herbst.) and Corcyra cephalonica (Stainton) with LC₅₀ values of 1.82, 2.19 and 1.83 μg/L respectively. ISTP also exhibits potent acetylcholinesterase (AChE) inhibitor activity in vivo and in vitro analysis. Additionally, molecular docking and molecular dynamics simulation analysis provide insight into the possible interaction between ISTP and AChE of S. oryzae, without any adverse effect on seed germination. In summary, ISTP from A. vulgaris source is a potential insecticide against stored grain insect pests and alternative to synthetic pesticides.

Kiwifruit plants are highly susceptible to increased atmospheric temperature, and the extreme high temperature often causes the loss of production and quality of the fruit. The γ-aminobutyric acid (GABA) has been widely proved to play important roles in plants in response to abiotic stresses, showing an important potential for application in agricultural industry to overcome environmental challenges. However, application of GABA in kiwifruit plants to resist external stresses has not been reported yet. This study found that pre-irrigation of kiwifruit plants with 0.5 mM GABA was effective in alleviating the heat damage on them. GABA treatment led to better antioxidant capacity and reduced ROS production in kiwifruit plants under high temperature. Moreover, exogenous GABA protected the photosynthetic system of kiwifruit plants when exposed to high temperature. Particularly, we found that endogenous ABA, Glu, Pro metabolisms were participated in the GABA-mediated heat resistance of kiwifruit plants. Furthermore, GABA treatment induced higher expression of AdHsps in kiwifruit plants, being partly responsible for their better performance under heat stress. In summary, this research first demonstrated that exogenous GABA treatment plays a positive role in kiwifruit plants to response to extreme heat stress.

Continuous application of fermented organic fertilizer can improve soil quality, while the performance of nitrogen (N) in the improved soils is rarely investigated. To investigate the fate of applied N in the soils with organic management history, the ¹⁵NH₂CO¹⁵NH₂ (¹⁵N abundance of 19.6 %) was employed as the exogenous N source to conduct an experiment in the Chinese cabbage and tomato rotation system under plastic shed condition. The cultivated soils have received 15-year of effective microorganism (EM) fermented organic fertilizer (EM-OF), N, P, K inorganic fertilizer (NPK-IF) and no fertilizer (NoF). The ¹⁵N use by cabbage and tomato, the soil ¹⁵N forms, as well as the ¹⁵N distribution were observed. Results showed that the ¹⁵N use efficiency of cabbage in the EM-OF, NPK-IF and NoF soils were 55.1 %, 37.3 % and 26.6 % respectively, showing significant (p ≤ 0.05) differences. The succeeding crop tomato could take up the soil residual ¹⁵N, and the highest ¹⁵N reuse efficiency was 7.1 % that detected in the NoF soil. The total ¹⁵N loss (6.0 %) from the rotation system was the lowest in the EM-OF soil, compared to that in the NPK-IF and NoF soils. It was concluded that the long-term fermented organic fertilizer applied soils can reduce urea ¹⁵N loss from plastic shed agriculture, mainly through improving the in-season crop ¹⁵N use efficiency.