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Root Function in Nutrient Uptake and Soil Water Effect on NO3^- -N and NH4^+ -N Migration

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Agricultural Sciences in China 2006年第5期5卷 377-383页

作者： SONG Hai-xing li sheng-xiu College of Resource and Environment Northwest A ＆ F University Yangling 712100 P.R. China College of Resource and Environment Hunan Agricultural University Changsha 410128 P.R. China

Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3^--N in arable soil were studied using summer maize （Zea mays L. var. Shandan 9） as a testing crop. Results showed that root growth and water supply had a significant effect on NO3^--N transfer and made NO3^--N distributed evenly from bulk soil to rhizosphere soil. Under a natural condition with irrigation, the difference of NO3^--N concentration at different distance points from a maize plant was smaller, while obvious difference of NO3^--N concentration was observed under conditions of limited root growth space without irrigation. Whether root growth space was restricted or not, the content of soil NO3^--N decreased gradually from 10 to 0 cm from the plant, being opposite to the root absorbing area in soils. When root-grown space was limited, changes of NO3^--N concentration at different distances from a plant were similar to that of water content in tendency. Results showed that NO3^--N could be transferred as solute to plant root systems with water uptake by plants. However, the transfer and distribution of NH4^--N were not influenced by root growth and soil water supply, being different to NO3^--N.

关键词： soil water root development nutrient transfer nitrate ammonium

Soil Organic Nitrogen and Its Contribution to Crop Production

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Journal of Integrative Agriculture 2014年第10期13卷 2061-2080页

作者： li sheng-xiu WANG Zhao-hui MIAO Yan-fang li Shi-qing College of Natural Resources and Environment Northwest A&F University School of Agriculture Henan University of Science and Technology State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University

Plant growth and crop production depend to a large extent on soil N supplying capacity （SNSC）： The higher the SNSC, the higher the dependence of crops on soil and the lower the N fertilizer recovery. Of the SNSC, soil organic N （ON） played a key role in supplying N nutrient to crop production and still does in many subsistence and low-input farming systems. In this paper, soil ON contents, types, chemical components and its contribution to plant production are reviewed up to date in details, the characteristics of ON in dryland soils discussed together with its chemical components, and the mineralization and availability to plants of some important chemical components are emphasized at the last part for practical considerations.

关键词： organic nitrogen in soil chemical components soil N supplying capacity mineralization contribution

Effects of Application of Nitrogen, Potassium and Glycinebetaine on Alleviation of Water Stress to Summer Maize

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Agricultural Sciences in China 2005年第10期4卷 767-773页

作者： ZHANG li-xin li sheng-xiu College of Resource and Environment Northwest A ＆ F University Yangling 712100 P.R. China

A pot experiment was conducted under water deficit and adequate water-supplied conditions with two maize genetypic varieties （Shaandan 9 and Shaandan 911） to study the effects of nitrogen, potassium and glycinebetaine （GlyBet） on the dry matter and grain yields as well as water use efficiency （WUE）. Determinations were made at different stages of the two varieties for revealing the function of these factors in increasing plant resistance to drought. Results showed that under a water-stressed condition, dry matter and grain yield were significantly reduced. However, the response of the two varieties to water stress was different： Shaandan 9 was significantly higher in dry matter and grain yields, and therefore could be regarded as a drought-resistant variety compared to Shaandan *** of nitrogen, potassium and glycinebetaine raised dry matter and grain yield to different levels, and thereby alleviated the water stress and increased water use efficiency. These effects were higher for Shaandan 911 than for Shaandan 9. Under water-stressed conditions application of N fertilizer, either at low rate or at high rate, significantly increased dry matter, grain yield and water use efficiency. A significant different effect was found for Shaandan 911 between N rates, but not so for Shaandan 9. However, with supplemental water supply, effects of N fertilization were obviously decreased, showing that in addition to supplying nutrient, N fertilizer has a function in increasing drought-resistance of the crop. Potassium and glycinebetaine exhibited a remarkable function in increasing dry matter and grain yields as well as water use efficiency under water stress while such effects were obviously declined, even vanished, with supplemental water supply, indicating the important contribution of these factors in rise of drought-resistance ability of a crop.

关键词： Nitrogen Potassium Glycinebetaine (GlyBet) Summer maize Water stress

Estimation of Nitrogen Fertilizer Use Efficiency in Dryland Agroecosystem

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Agricultural Sciences in China 2001年第1期 89-94页

作者： li Shi-qing li sheng-xiu College of Resources and Environmental Sciences Northwest Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 College of Resources and Environmental Sciences Northwest Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100

A field trial was carried out to study the nitrogen fertilizer recovery by four crops in succession in manurial loess soil in Yangling. The results showed that the nitrogen fertilizer not only had the significant effects on the first crop , but also had longer residual effects, even on the fourth crop. The average apparent nitrogen fertilizer recovery by the first crop was 31.7%, and the accumulative nitrogen recovery by the 4 crops was high as 62.3%, and the latter was double as the former. It is quite clear that the nitrogen fertilizer recovery by the first crop was not reliable for estimating the nitrogen fertilizer unless the residual effect of nitrogen fertilizer was included.

关键词： Dry farming Ecological systen of farmland Nitrogen fertilizer recovery Residual effect

Effect of CO_2 Concentration on Nitrogen Metabolism of Winter Wheat

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Agricultural Sciences in China 2005年第8期4卷 601-608页

作者： MEN Zhong-hua li sheng-xiu College of Resources and Environment Sciences Northwest A＆F University Yangling 712100 P.R.China College of life Science Inner Mongolia University of Science and Technology Baotou 014030 P.R. China

Hoagland＇s solution was used as water culture medium to study the effect of CO2 concentration on nitrate metabolism of wheat under natural light and light-shaded conditions. NO3^-N, NH4^＋-N, nitrate reductase activity, total uptake N by wheat plants during solution cultural period and total N in plants were determined for comprehensive evaluation of the effect. Results showed that under both natural light and light-shaded conditions, addition of CO2 increased NO3^-N uptake and its assimilative capabilities by plants. However, there were some difference between shoots and roots. With increase of CO2 concentration, the concentration of NO3^-N and NH4^＋-N as well as nitrate reductase activity were all decreased for shoots while the difference was not so distinct in roots, and the nitrate reductase activity was not decreased, but increased. Since NO3^-N uptake by plants from the solution and the total N in plants were much higher by CO2 addition, it may be concluded that addition of CO2 has resulted in rise of nitrate absorption, assimilation and metabolism of wheat.

关键词： CO2 concentration Winter wheat Water culture Nitrogen metabolism

Effects of High Ammonium Concentration on Growth and Nutrient Uptake of Lettuce Plants with Solution Culture

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Agricultural Sciences in China 2005年第11期4卷 833-838页

作者： TIAN Xiao-hong li sheng-xiu College of Resources and Environmental Sciences Northwest A ＆ F University Yangling 712100 P.R.China

A nutrition solution experiment was conducted over two months to investigate the response of vegetable crops to high concentrations of ammonium, using lettuce （Lactuca sativa L. cv. Angustana Irish） as a test crop. Ammonium concentrations were designed in 5 levels, ranging from 12 mmol N L^-1 to 22 mmol N L^-1 and local tap water was used as water source. At the first culture stage （0-9 days）, lettuce plants maintained normal growth while the lettuce roots were increasingly impaired. During the subsequent three stages the root structure was greatly damaged, and roots became brown or black through continuous supply of high concentration of ammonium. However, there was no obvious reduction of the aboveground biomass of the plants in the high ammonium treatments compared to those supplied with nitrate alone. In contrast to results obtained in another experiment from us with distilled water, the detrimental effect of high ammonium concentration on lettuce growth was greatly alleviated. Based on the results, it was postulated that the small amount of nitrate and the higher amount of bicarbonate existed in the tap water might mitigate the adverse effects of high ammonium N. The higher bicarbonate content in water and soil has usually been regarded as a major constraint factor limiting plant growth in calcareous soil areas. However, the reaction of bicarbonate to ammonium might produce positively interactive effect on reduction of both damages. The lettuce plants grown in ammonium solutions took up less P, K, Fe, Mn and Cu and more Ca than those grown in the nitrate nutrient solution. In conclusion, the results indicated that the N form imposed an obvious influence on absorption of cations and anions. Supplying ammonium-N stimulated transport of Ca, Mg and Mn to shoots of lettuce.

关键词： High concentration ammonium Lettuce Nutrient solution culture Tap water

Estimation of the Biological Methods of Assessing Soil N-Supplying Capacity in Calcareous Soil

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Agricultural Sciences in China 2007年第10期6卷 1224-1234页

作者： JIN Fa-hui li Shi-qing LU Hong-ling li sheng-xiu State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A＆F University~Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 P.R.China College of Resources and Environmental Sciences Northwest A＆F University Yangling 712100 P.R.China

Although many biological methods are used to determine soil nitrogen supplying capacity, there are certain differences in the results for different types of soils and various ways of measurement due to the complexity of soil N conformation, the high variance of soil and microorganism, and the difference of environment. Therefore, it is not clear about which biologic incubation method is better for calcareous soil. In this study, pot experiments were performed by using 25 different calcareous surface soil samples on the Loess Plateau and taking the N uptake of wheat and corn with leaching soil initial nitrate and without leaching in pot experiments as the control to investigate the difference of eight biological incubation methods for reflecting soil nitrogen supply capacity. The eight biological methods are waterlogged incubation, aerobic incubation for 2 weeks and for 4 weeks, dry-wet alternation aerobic incubation for 2 weeks, long-term alternate leaching aerobic incubation （and N mineralization potential, No）, short-term leaching aerobic incubation, microbial biomass carbon （Bc）, and microbial biomass nitrogen （BN） method, respectively. Among these methods, the dry-wet alternation aerobic incubation and aerobic incubation for 4 weeks were the modification of the method of aerobic incubation for 2 weeks according to the actual farmland moisture. The results showed that the correlation coefficients between these methods and crop uptake N with leaching soil initial nitrate were 0.530, 0.700, 0.777, 0.768, 0.764 （and 0.790, No）, 0.650, 0.555, and 0.465, respectively （r0.05 = 0.369, r0.0l = 0.505）. While without leaching soil initial nitrate, their coefficients were 0.351, 0.963, 0.962, 0.959, 0.825 （and0.812, No）, 0.963, 0.289, and 0.095, respectively （r0.05 = 0.369, r0.01 = 0.505）. In conclusion, excluding the soil initial nitrate, the correlation coefficients between the eight methods and crop uptake N were, from high to low, N0, aerobic incubation for 4 weeks, dry

关键词： soil nitrogen supplying index biological methods mineralized N

Advances in Nitrogen Loss Leached by Precipitation from Plant Canopy

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Agricultural Sciences in China 2008年第4期7卷 480-486页

作者： li Shi-qing JI Chun-rong FANG Ya-ning CHEN Xiao-li li sheng-xiu State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau/Institute of Soil and Water Conservation Chinese Academy of Sciences/Ministry of Water Resources Yangling 712100 P.R China Department of Natural Resources and Environment Northwest A ＆ F University Yangling 712100 P.R.China

Function of canopy in changing nutrient cycle and flux is one of the focuses in recent years. On the basis of comprehensively appraising published research, we analyzed the nitrogen loss leaching from plant canopy and several factors which affected it. We pointed out the disadvantages of the published researches and the key issues that ought to be solved：（1） The menstruation need to be advanced, and the research should be carried out on nitrogen loss leaching from the canopy of the field plant. （2） If the nitrogen is leached from the plant canopy, the research on the type of nitrogen loss should be carried out, and the nitrogen use efficiency of different varieties should be dealt on a research perspective with regard to the nitrogen leaching. （3） The research should be conducted on the mechanism and pathway, and the progress of nitrogen leaching; and the factors affecting nitrogen leaching should be included in the research, such as the leaf area of different growth stages, stomata densities, stomata conductance, and the apparent free space, which are beneficial to explain the mechanism of nitrogen leaching from the plant canopy.

关键词： plant canopy nitrogen loss research advances

Tanshinone ⅡA improves Alzheimer’s disease via RNA nuclearenriched abundant transcript 1/microRNA-291a-3p/member RAS oncogene family Rab22a axis

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World Journal of Psychiatry 2024年第4期14卷 563-581页

作者： Long-xiu Yang Man Luo sheng-Yu li Department of Neurology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530000Guangxi Zhuang Autonomous RegionChina Department of Neurology Wuming Hospital of Guangxi Medical UniversityNanning 530199Guangxi Zhuang Autonomous RegionChina

BACKGROUND Alzheimer’s disease(AD)is a neurodegenerative condition characterized by oxidative stress and *** ⅡA(Tan-ⅡA),a bioactive compound isolated from Salvia miltiorrhiza plants,has shown potential neuroprotective effects;however,the mechanisms underlying such a function remain *** To investigate potential Tan-ⅡA neuroprotective effects in AD and to elucidate their underlying *** Hematoxylin and eosin staining was utilized to analyze structural brain tissue *** assess changes in oxidative stress and neuroinflammation,we performed enzyme-linked immunosorbent assay and western ***,the effect of Tan-ⅡA on AD cell models was evaluated in vitro using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide *** changes related to the long non-coding RNA(lncRNA)nuclear-enriched abundant transcript 1(NEAT1)/microRNA(miRNA,miR)-291a-3p/member RAS oncogene family Rab22a axis were assessed through reverse transcription quantitative polymerase chain *** In vivo,Tan-ⅡA treatment improved neuronal morphology and attenuated oxidative stress and neuroinflammation in the brain tissue of AD *** vitro experiments showed that Tan-ⅡA dose-dependently ameliorated the amyloid-beta 1-42-induced reduction of neural stem cell viability,apoptosis,oxidative stress,and *** this process,the lncRNA NEAT1-a potential therapeutic target-is highly expressed in AD mice and downregulated via Tan-ⅡA ***,NEAT1 promotes the transcription and translation of Rab22a via miR-291a-3p,which activates nuclear factor kappa-B(NF-κB)signaling,leading to activation of the pro-apoptotic B-cell lymphoma 2-associated X protein and inhibition of the anti-apoptotic B-cell lymphoma 2 protein,which exacerbates ***-ⅡA intervention effectively blocked this process by inhibiting the NEAT1/miR-291a-3p/Rab22a axis and NF-κB *** This study demonstrates that

关键词： TanshinoneⅡA Alzheimer’s disease Nuclear-enriched abundant transcript 1 Member of RAS oncogene family Rab22a Reactive oxygen species