Understanding the effects of external organic and inorganic components on soil fertility and quality is essential for improving low-yielding soils. We conducted a field study over two consecutive ...rice growing seasons to investigate the effect of applying chemical fertilizer (NPK), NPK plus green manure (NPKG), NPK plus pig manure (NPKM), and NPK plus straw (NPKS) on the soil nutrient status, enzyme activities involved in C, N, P, and S cycling, microbial community and rice yields of yellow clayey soil. Results showed that the fertilized treatments significantly improved rice yields over the first three experimental seasons. Compared with the NPK treatment, organic amendments produced more favorable effects on soil productivity. Notably, the NPKM treatment exhibited the highest levels of nutrient availability, microbial biomass carbon (MBC), activities of most enzymes and the microbial community. This resulted in the highest soil quality index (SQI) and rice yield, indicating better soil fertility and quality. Significant differences in enzyme activities and the microbial community were observed among the treatments, and redundancy analysis showed that MBC and available N were the key determinants affecting the soil enzyme activities and microbial community. The SQI score of the non-fertilized control (0.72) was comparable to that of the NPK (0.77), NPKG (0.81) and NPKS (0.79) treatments but significantly lower compared with NPKM (0.85). The significant correlation between rice yield and SQI suggests that SQI can be a useful to quantify soil quality changes caused by different agricultural management practices. The results indicate that application of NPK plus pig manure is the preferred option to enhance SOC accumulation, improve soil fertility and quality, and increase rice yield in yellow clayey soil.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Inoculating microbial inoculants to speed up the decomposition of returning straw is currently a hot topic. Meanwhile, the soil moisture content (SMC) could change the diversity, abundance, and ...metabolism of the soil microbial community structure, which affects the straw degradation rate under the straw returning condition. In this research, rumen microorganisms with strong decomposing abilities in natural systems were used as inoculants to promote straw decomposing and returning to the field. The effects of the SMC on straw decomposition under rumen fluid (RF)-induced returning were investigated. Experiments were conducted for 30 days with typical paddy soil in the south of China under conditions of 30%, 70%, and 100% SMC. With an increase in the SMC within a certain range (30~100%), the decomposition rate of straw showed a trend of first rising and then falling. Treatments of 70% SMC with RF addition generally achieved the maximum rate of straw degradation. The peak value was 49.96%, which was 2.67-fold higher than the treatments of 30% SMC with RF addition (18.74%) and 24.1% higher than those of the control with 70% SMC (40.3%) (p < 0.05). Moreover, a straw structural analysis proved that at 70% SMC, microorganisms from RF favored the destruction of functional groups on the straw surface and the degradation of cellulose. Meanwhile, it was shown that RF could promote the decay of straw, leading to increments in enzyme activities and soil nutrients. The higher the soil moisture content, the higher the key soil enzyme activities. This indicates that the diversity and abundance of cellulose-degrading bacteria and fungi in soil microorganisms and rumen microorganisms were changed with different soil moisture contents. The experimental findings suggest an innovative way to further utilize rumen microorganisms.
As natural selenium (Se)-rich soil in China is generally characterized by a high geological background of cadmium (Cd), the safe utilization of such seleniferous soil remains a challenge. The ...accumulating evidence shows that the threshold value of the Se:Cd ratio is a determinant of regulating Cd accumulation in plants. However, the factors modulating the soil’s Se:Cd ratio in selenium-enriched regions are not well understood. Here, a comprehensive study aimed at quantitatively analyzing the effects of land-use types, parent-material types, and soil properties on the distribution and influencing factors of Se, Cd, and the Se:Cd ratios. According to land use and parent-material types, 77 soil samples were collected in Yuanzhou District, a typical naturally seleniferous area in the subtropical hilly area. The results suggested that, compared with quaternary red clays (qrc), the Se content of soils derived from river and lake sediments (rls) and weathered acidic crystalline rocks (wacr) decreased by 5.81%–19.75%, while the weathered quartzite (wq)-derived soils was increased significantly. The soil Cd content in an orchard was significantly reduced compared with that in a paddy field. A redundancy analysis (RDA) revealed that SOM, Total K, and Total P significantly affected the changes in Se and Cd contents. In addition, the land-use type had the most significant effect on the Se:Cd ratio, with a regression coefficient of −0.6999 analyzed by the binary logistic regression model (p < 0.05). Furthermore, pH and Total K were the critical soil properties in controlling the Se:Cd ratio. The study indicated that the Se:Cd ratio in natural selenium-rich soil was mainly regulated by land-use types. Therefore, it is a feasible measure to regulate the Se:Cd ratio by using agronomic practices, mainly regulating soil pH, for the safe utilization of selenium-rich soil with a high Cd background.
It is one of the effective ways to reduce the amount of nitrogen fertilizer by using rice varieties with adaptation to low nitrogen environment or high efficient utilization of soil nitrogen. Red ...soil agro-ecosystem of South China is an important production base of double-cropped paddy rice. However, the rice yield and N use rate in this area have been at a low level especially for early rice, due to the unreasonable use of nitrogen fertilizer and the acid characteristic of red soil. To screen early rice cultivars with high nitrogen efficiency and reveal their physiological characterizations, twenty one rice cultivars widely grown in red soil area of South China were tested in randomized block field experiments under normal and low nitrogen supplies. The biological characteristics of early rice varieties with high nitrogen efficiency were identified by analyzing parameters related to yield and its components, the aboveground nitrogen accumulation, the leaf SPAD value and photosynthetic rate, and nitrate Reductase activity. Based on rice yield and nitrogen efficiency analysis, Zhongxuan972, Zhongjiazao17, Zhongzu 7 and zhongyouzao13 were selected as high nitrogen efficient cultivars due to their more than 6000 kg ha -1 yields and more than 0.81 nitrogen efficiency, and Zhongjiazao2, Xiangzaoxian32, Jiayu948 and Zhongxuan 181 as low nitrogen efficient cultivars due to their lower yield and less than 0.70 nitrogen efficiency. Comparison of yield components revealed that the significant difference between two type cultivars was effective grain numbers of per unit area (panicle number xspikelet number per panicle). The aboveground nitrogen accumulation and net photosynthetic rate in high nitrogen efficient cultivars were significantly higher than those in low ones at the heading stage under nitrogen-free condition, and there was not a significantly difference in leaf SPAD between the high and low nitrogen efficient cultivars. However, leaf SPAD values of high nitrogen efficient cultivars declined more slowly than that of the other four low nitrogen efficient cultivars under nitrogen-free condition. Nitrate Reductase activities of high nitrogen efficiency varieties under nitrogen-free condition were 38% to 53% activities under normal nitrogen condition, and nitrate Reductase activities of low nitrogen efficiency varieties were 22% to 35% activities. It suggested that the high nitrogen efficient rice cultivars had more grain numbers of per unit area under low nitrogen supply condition, their functional leaves maintained a higher level of photosynthetic rate and nitrate Reductase activity and lower chlorophyll decomposition rate especially during heading stage, which might be the reason for enhancing nitrogen assimilation and acquiring the higher yields.
Schisantherin A, a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been used as an antitussive, tonic, and sedative agent under the name of Wuweizi in Chinese ...traditional medicine. In the present study, we carry out a screening program to identify the anti-inflammatory potentials of schisantherin A. We found that schisantherin A reduced lipopolysaccharide (LPS (1 mg/L))-induced levels of TNF-α, IL-6, NO, and PGE2 (
p
< 0.01 or
p
< 0.05), and also reduced levels of iNOS and COX-2 in RAW 264.7 macrophages in a concentration-dependent manner. We further investigated signal transduction mechanisms to determine how schisantherin A affects. RAW264.7 cells were pretreated with 0.5, 2.5, or 25 mg/L of schisantherin A 1 h prior to treatment with 1 mg/L of LPS. Thirty minutes later, cells were harvested and mitogen activated protein kinases (MAPKs) activation and IκBα was measured by Western blot. Alternatively, cells were fixed and nuclear factor-κB (NF-κB) activation was measured using immunocytochemical analysis. Signal transduction studies showed that schisantherin A significantly inhibited extracellular signal-regulated kinase (ERK), p38, and c-jun NH2-terminal kinase (JNK) phosphorylation protein expression. Schisantherin A also inhibited p65-NF-κB translocation into the nucleus by IκBα degradation. By using specific inhibitors of ERK, JNK and p38, we found that schisantherin A may inhibit TNF-α mostly through ERK pathway. Therefore, schisantherin A may inhibit LPS-induced production of inflammatory cytokines by blocking NF-κB and MAPKs signaling in RAW264.7 cells.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Schisantherin A, a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been used as an antitussive, tonic, and sedative agent under the name of Wuweizi in Chinese ...traditional medicine. In the present study, we carry out a screening program to identify the anti-inflammatory potentials of schisantherin A. We found that schisantherin A reduced lipopolysaccharide (LPS (1 mg/L))-induced levels of TNF-α, IL-6, NO, and PGE2 (p<0.01 or p<0.05), and also reduced levels of iNOS and COX-2 in RAW 264.7 macrophages in a concentration-dependent manner. We further investigated signal transduction mechanisms to determine how schisantherin A affects. RAW264.7 cells were pretreated with 0.5, 2.5, or 25 mg/L of schisantherin A 1 h prior to treatment with 1 mg/L of LPS. Thirty minutes later, cells were harvested and mitogen activated protein kinases (MAPKs) activation and IκBα was measured by Western blot. Alternatively, cells were fixed and nuclear factor-κB (NF-κB) activation was measured using immunocytochemical analysis. Signal transduction studies showed that schisantherin A significantly inhibited extracellular signal-regulated kinase (ERK), p38, and c-jun NH2-terminal kinase (JNK) phosphorylation protein expression. Schisantherin A also inhibited p65-NF-κB translocation into the nucleus by IκBα degradation. By using specific inhibitors of ERK, JNK and p38, we found that schisantherin A may inhibit TNF-α mostly through ERK pathway. Therefore, schisantherin A may inhibit LPS-induced production of inflammatory cytokines by blocking NF-κB and MAPKs signaling in RAW264.7 cells.PUBLICATION ABSTRACT
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Schisantherin A, a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been used as an antitussive, tonic, and sedative agent under the name of Wuweizi in Chinese ...traditional medicine. In the present study, we carry out a screening program to identify the anti-inflammatory potentials of schisantherin A. We found that schisantherin A reduced lipopolysaccharide (LPS (1 mg/L))-induced levels of TNF-alpha, IL-6, NO, and PGE2 (p<0.01 or p<0.05), and also reduced levels of iNOS and COX-2 in RAW 264.7 macrophages in a concentration-dependent manner. We further investigated signal transduction mechanisms to determine how schisantherin A affects. RAW264.7 cells were pretreated with 0.5, 2.5, or 25 mg/L of schisantherin A 1 h prior to treatment with 1 mg/L of LPS. Thirty minutes later, cells were harvested and mitogen activated protein kinases (MAPKs) activation and I kappaB alpha was measured by Western blot. Alternatively, cells were fixed and nuclear factor-kappaB (NF-kappaB) activation was measured using immunocytochemical analysis. Signal transduction studies showed that schisantherin A significantly inhibited extracellular signal-regulated kinase (ERK), p38, and c-jun NH2-terminal kinase (JNK) phosphorylation protein expression. Schisantherin A also inhibited p65-NF-kappaB translocation into the nucleus by I kappaB alpha degradation. By using specific inhibitors of ERK, JNK and p38, we found that schisantherin A may inhibit TNF-alpha mostly through ERK pathway. Therefore, schisantherin A may inhibit LPS-induced production of inflammatory cytokines by blocking NF-kappaB and MAPKs signaling in RAW264.7 cells.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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