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The feature and change trend of N, P and K cycling and balance in farmland ecosystem of Luancheng County at the piedmont of Taihang were analyzed. The status of nutrient balance was appraised, and the rational way to apply fertilizer was put forward. The result indicated that N balance went through a process from slight deficit to surplus during 1985-2000, changing from deficit of 1.4% in 1985 to surplus of 48.6% in 2000. Potassium balance changed gradually from serious deficit of 82% to slight surplus of 4.6%, but was still deficit in many fields. P budget was surplus ever since 1985. Comparing with the output of nutrients, the inputs of N and P were excessive, but the K input was short. Under the current soil fertility and crop planting structure, the countermeasure to control the application amount of N and P and to increase the application rate of K should be carried out, so that, there would be no significant surplus N emitting or leaching from soil into environment. The technique to return crop straw into farmland should be extended to increase the nutrient recycling rate.
Segments of sterile germinating plants were used to derive the tissue culture. Tests of the optimal hormonal composition of the medium from the standpoint of the growth of cultures revealed that the highest growth in biomass was achieved in the medium with an addition of 2.4-D (0.1, 1.0 mg.l-1), NAA (10.0 mg.l-1), and a combination of IAA (1.0 mg.l-1) + K (1.0 mg.l-1). The difference between these values was statistically insignificant. Other tested concentrations of growth regulators showed statistically significantly lower increases. The effects of different types of growth regulators and their concentrations on the production of selected metabolites in the tissue cultures were also examined and compared with the results obtained from the extract of the drug. Of alkaloids, stachydrine was demonstrated both in the extract of the drug and the extracts from all tested calluses regardless of the type and concentration of the growth regulator. Of flavonoid substances, two stains were demonstrated in the extract from the drug as well as in the extracts from all tested calluses. Neither of them was identical with the employed standards of rutin and quercetin. The results of TLC of iridoid substances were different in the extract from the drug (12 stains) and in the extracts from calluses (4 stains--3 identical with the stains in the extract from the drug). As to saccharides, three of them--glucose, fructose, and sucrose--were identified in the extract of the drug as well as in the extracts from all calluses.
Based on the data of long term located experiment, this paper studied the characteristics of nutrient and water cycling and balance and of energy flow in upland red soils with different planting system. The results showed that in red soil areas, the rainfall from March to June accounted for 60% of the whole year, which induced frequent seasonal drought and severe water and soil loss. The application of N, P and K on upland red soil was overabundant and unbalanced, which induced a reduced ratio of input and output. Optimized planting mode could increase the water and light utilization efficiency, decrease the frequency and degree of occurred drought, and increase the nutrient recycling rate. The main measures for rationally developing and utilizing red soil should be establishing compound agro-ecosystem model of planting and feeding, saving irrigation water, increasing mulch, cover-cultivating crops and forests, increasing the proportion of organic fertilizer, realizing rational and balanced fertilization, further optimizing planting structure, regulating energy input structure, and adopting multilevel-technologies of food chain utilization.
A method for the isolation of sesquiterpenols from the Japanese Cedar, Cryptomeria japonica D. Don by preparative reversed-phase high performance liquid chromatography (RP-HPLC) was established. The preparation of the sesquiterpenols was carried out on a preparative liquid chromatograph with a YWC-Pack C18 column, and the mobile phase was isopropanol-methanol-hexane-water (50:35:10:5, v/v) at a flow rate of 5.0 mL/min. The two sesquiterpenols, (-)-cubebol and (+)-2,7(14),10-bisabolatrien-1-ol-4-one, were separated by liquid chromatography and identified by spectroscopic analyses (ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS)). The purities of the two sesquiterpenols were 98.7% and 99.1%, respectively.