为研究不同地区蜂胶提取物中组分含量的差异及抗氧化活性的大小,采用75％乙醇溶液对9个蜂胶样品进行提取,以高效液相色谱法(high performance liquid chromatography,HPLC)对不同提取物中多酚类成分进行定性和定量分析.并利用氧化自由基吸收能力(oxygen radical absorbance capacity,ORAC)法和用流式细胞仪Hep G2细胞模型评估了9个蜂胶样品的体外和细胞水平抗氧化能力.结果表明:蜂胶样品中含有包括黄酮、酚酸及酯类物质在内的大量多酚类成分,其中含量较高的黄酮类成分有短叶松素-3-乙酸酯、松属素、柯因、短叶松素、高良姜素,含量较高的酚酸及酯类成分有咖啡酸苯乙酯、p-香豆酸、咖啡酸、异阿魏酸.ORAC法结果显示所有蜂胶样品都具有很好的体外抗氧化能力;在细胞水平上,所有样品也都表现出一定的抗氧化能力.9个总黄酮和总酚酸含量高的蜂胶具有较强的抗氧化能力.

The effect of fertilizer application on biomass dry weight and element distribution of various organs of maize was investigated from the aspect of microscopic view to disclose the internal mechanism of fertilizer effect on crop. Five fertilizer treatments: no fertilizer (CK), nitrogen phosphorus fertilizer (NP), nitrogen potassium fertilizer (NK), phosphorus potassium (PK), and nitrogen phosphorus potassium fertilizer (NPK) were designed. Field experiment on the response of biomass dry weight and N, P, K, Cu, Zn, Fe, and Mn element distribution of stem, leaf and seed of maize (Zea mays L.) to different fertilizer treatments application was carried out. The results showed that dry weight and element content of various organs of maize were different. N content of various organs followed this order leaf > seed > stem; P content of various organs was seed > leaf > stem; K content was stem > leaf > seed; and Fe content was leaf > stem > seed. Fertilizer application reduced the differences of N, P, K, and Fe contents of various organs, and changed the size order of the dry weight and the Cu and Zn contents of leaf, seed and stem. Except for individual treatment, the response direction of N, P and Fe elements to fertilizer application was similar to Cu and Zn. The response of element content of various organs of maize to different fertilizer combinations was also different. The response extent of N, P and K major elements to fertilizer application was larger than microelement of Cu, Zn, Fe, and Mn; the response extent of stem and leaf was larger than seed; the response to NPK fertilizer treatment was bigger than NP, NK and PK. In the whole, response differences of element distribution to various fertilizer treatments were not remarkable. Besides, element distribution of various organs of maize was also influenced by the mutual effect of fertilizer varieties. The response direction and extent of various element distributions to different fertilizer treatments had both similarities and differences. Adjusting fertilizer application could change the biomass dry weight and element distribution of various organs of maize, thus promote the uptake and cycle of nutrient. This investigation could provide useful information for high production.

用GreenSeeker和SPAD-502测定了不同氮素处理的冬小麦冠层NDVI与叶片SPAD值,分析了它们与叶片全氮、叶绿素含量及产量间的关系.结果表明:冬小麦抽穗期SPAD值和NDVI值均与叶绿素含量呈极显著正相关;除抽穗期和返青期外,SPAD值与叶氮含量、叶绿素含量的相关系数在其余各生育期均达到显著或极显著水平;NDVI值与叶氮含量、叶绿素含量在拔节期、乳熟期的相关性同SPAD值一致;SPAD值可以进行叶绿素的诊断,NDVI值可以进行氮的诊断.氮营养诊断时期应该选择拔节期.通过回归建立了基于SPAD值、NDVI值的产量估测模型,可以通过SPAD值、NDVI值对冬小麦产量进行估算.

To avoid interference of soil on canopy spectrum and improve the estimation accuracy of wheat yield,in this experiment,based on winter wheat varieties(Triticum aestivum L.) under the condition of middle-low yield fields,canopy reflectance were monitored using ASD FieldSpec Pro spectrometer(Spectral range from 350 nm to 2 500 nm) and the monitoring was conducted in the fixed site in the whole growing stages.The change trend of vegetation cover was analyzed,NDVI and C-NDVI were calculated from NDVI and vegetation cover within growing stages.The results showed that wheat can be separated from the soil based on their differences in RGB,H,and L values,so the percentage of wheat in unit area can be obtained.C-NDVI is the NDVI modified by vegetation coverage,which increased pertinence to spectral information of wheat canopy.In this paper,good prediction results were obtained from single regression of yield and C-NDVI in grain-filling stage or multiple regression of yield and C-NDVI in different stages,and the decision coefficients were 0.849 and 0.853,respectively.Comparatively,the multiple regression model is more reliable and stable because the changes of C-NDVI in different stages were considered in the model.This method greatly improves the wheat yield estimation accuracy using ground spectral data.

Analyzing the spatial distribution characteristics and influencing factors of soil phosphorus content by the software ArcGIS9.0.Using stratified sampling method,505 sample points in top soil were selected.The results showed that the average content of soil total phosphorus(STP) and soil available phosphorus(SAP) were(0.73±0.18)g·kg-1 and(21.31±16.08)mg·L-1,respectively.The spatial distribution of STP mainly appeared as droplets.The highest value region(>0.80 g·kg-1) mainly existed in the middle of Hebei,the west of Shandong and the relationships converge of Shandong,Anhui and Jiangsu.From the middle of Huang-Huai-Hai plain,reduced towards the north and the south.The lowest value region(<0.50 g·kg-1)mainly existed in along the north and the south narrow area.The spatial distribution of SAP on the whole appeared as small droplets.The highest value region(>24.0 mg·L-1) mainly existed middle of Huang-Huai-Hai plain,and declined towards the northeast and south.The lowest value region(<12.0 mg·L-1)mainly lay to the north and south verge of the area.The highest value region of STP and SAP mainly existed middle of Huang-Huai-Hai plain,distribution was almost consistent,reduced towards the north and the south.By soil parent material,difference soil type has produced difference content of phosphorus.The soil texture,the using amounts of phosphorus and part chemistry properties affected the soil phosphorus contents.

The red edge characteristics of winter wheat canopy at different nitrogen levels and growth periods,and their relationships with agronomic components were studied by the measurement of canopy spectra using Field Spec Pro FR2500.The results show that significant differences of canopy spectra are found at 550 nm, 680 nm,980 nm and 1100 nm,350680 nm,7501100 nm,which can be used as the wave bands for nutrition diagnostic of the crop.The red edge position(REP),Location of minimum chlorophyll absorption(Lo) and max of first derivative of reflectance(FD-Max) increase with more nitrogen application during jointing,booting and filling stages,while,the red edge width(Lwidth) decreases.On the whole,little differences are found between the different nitrogen application treatments,but the differences between the fertilizer application and no nitrogen application are quite different.With the growth of winter wheat,REP and Lo move toward longer wavelength,presenting the red shift,while they move to short wavelength from the booting stage,presenting the blue shift.The correlations between REP and agronomic components are better than those between the other red edge parameters and agronomic components.Except aboveground fresh biomass,there are significant correlations between the REP and leaf area index(LAI),leaf water content(LWC),chlorophyll(CHl),leaf soluble protein(LP),leaf fresh biomass(LB) and leaf nitrogen content(LN).There are significantly positive correlations between Lo and LAI,LWC,CH1,LB,SPAD readings and soluble protein,and the correlations between Lwidth and LAI,LWC,LN,CH1,LB,and soluble protein are significantly positive.There are significantly positive correlations between FD-Max and LAI,LWC and LB as well,while the correlation between FD-Max and LN is significantly negative.The mathematical relationships of red edge parameters and agronomic components can be helpful for the estimation of the agronomic parameters.