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The amount and time of fertilization play an important role in the quality and yield of citrus. Moreover, twice fertilization in the spring (March) and summer (July) are generally applied in citrus orchards, of which the appropriate proportion is unclear, especially in Ganzhou. Therefore, the two-year field experiment containing three proportions (60/40, 80/20, 100/0) of spring and summer fertilization was carried out with a 15-year-old Newhall orange orchard to recommend the optimum fertilization proportion for orchard. Results showed that variations of soil available N, P, K concentrations resulting from different spring and summer fertilization proportion significantly affected orange fruit quality and yield. The soil available nitrogen (N), phosphorus (P), and potassium (K) concentrations fertilized with a proportion of 80/20 spring and summer were higher overall the year. The spring and summer fertilizer application with 80/20 increased fruit yield by 35.14%, and had higher total soluble solids and lower titrated acid. Moreover, the only one-time fertilization exhibited almost the same fruit yield, fruit N, P, K removal, but lower fruit titrated acid content and higher solid acid ratio. The present study results demonstrated that increasing the proportion of spring fertilization particularly the proportion of 80/20 could be a recommended dose for obtaining higher fruit yield and quality. [ABSTRACT FROM AUTHOR]

The rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo solution cultivation at seedling stage to investigate the effects of selenite addition on the selenium (Se) absorption and distribution, root morphology and physiological characteristics of rape seedlings. The results showed that the bioaccumulation ability of Se decreased significantly with increasing the Se application rate, but the Se distribution coefficient remained around 0.9 with no significant influence. The application of 10 μmol . L-1 selenite stimulated the growth of rape seedlings through improving the root physiological characteristics and root morphology significantly, including significantly increasing the production of superoxide radical ( O2.- ) rate and the activities of superoxide dismutase (SOD) , peroxidase (POD) and fungal catalase (CAT) in the root system, which resulted in a reduction of the lipids peroxidation (MDA) content as much as 26.0%, consequently increasing the root activity as much as 17.4%. The promoting degrees of selenite on root morphological parameters were from strong to weak in such a tendency: root volume > total surface area > number of root forks > total root length > number of root tips > average diameter. However, such positive effects had no significant difference with those in treatment with 1 μmol . L-1 selenite, indicating that small amounts ( ≤10 μmol .L-1) of selenite were able to increase the activity of antioxidant enzymes and reduce the content of MDA in root system, which could increase root activity and improve root morphology, hence increased the biomass of rape seedlings. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is highly toxic, even at very low concentrations, to both animals and plants. Pollen is extremely sensitive to heavy metal pollutants; however, less attention has been paid to the protection of this vital part under heavy metal stress. A pot experiment was designed to investigate the effect of foliar application of Se (1 mg/L) and Mo (0.3 mg/L) either alone or in combination on their absorption, translocation, and their impact on Cd uptake and its further distribution in Brassica napus, as well as the impact of these fertilizers on the pollen grains morphology, viability, and germination rate in B. napus under Cd stress. Foliar application of either Se or Mo could counteract Cd toxicity and increase the plant biomass, while combined application of Se and Mo solutions on B. napus has no significant promotional effect on plant root and stem, but reduces the seeds’ weight by 10–11%. Se and Mo have decreased the accumulated Cd in seeds by 6.8% and 9.7%, respectively. Microscopic studies, SEM, and pollen viability tests demonstrated that pollen grains could be negatively affected by Cd, thus disturbing the plant fertility. Se and Mo foliar application could reduce the toxic symptoms in pollen grains when the one or the other was sprayed alone on plants. In an in vitro pollen germination test, 500 μM Cd stress could strongly inhibit the pollen germination rate to less than 2.5%, however, when Se (10 μM) or Mo (1.0 μM) was added to the germination medium, the rate increased, reaching 66.2% and 39.4%, respectively. At the molecular level, Se and Mo could greatly affect the expression levels of some genes related to Cd uptake by roots (IRT1), Cd transport (HMA2 and HMA4), Cd sequestration in plant vacuoles (HMA3), and the final Cd distribution in plant tissue at the physiological level (PCS1). [ABSTRACT FROM AUTHOR]

Solution culture experiments were conducted to investigate the effect of wastewater nitrogen levels and NH 4 + /NO 3 - on nitrogen removal ability and the nitrogen component of Myriophyllum aquaticum . Experiments with three nitrogen levels and NH 4 + /NO 3 - were set up as follows:20, 100, and 200 mg·L -1 and NH 4 + /NO 3 - 1:0, 0.5:0.5, and 0:1. The results showed that the biomass of plants increased fastest during the first week. The plants treated with NH 4 + /NO 3 - =1:0 with nitrogen levels of 20 and 100 mg·L -1 and those treated with NH 4 + /NO 3 - =0.5:0.5 with a nitrogen concentration of 200 mg·L -1 exhibited higher biomass than the others. The removal rates of water total nitrogen, ammonium nitrogen, and nitrate nitrogen during the first week were the maximum for all treatments and increased with water nitrogen levels. There were no significant differences in the removal rate between ammonium nitrogen and nitrate nitrogen with a nitrogen level of 20 mg/L, while with nitrogen levels of 100 and 200 mg·L -1 , the nitrate removal rates were higher than those for ammonium nitrogen. The Myriophyllum aquaticum nitrogen accumulation and its contribution rate to nitrogen removal from water and sediment were all increased with water nitrogen levels and increased fastest during the first week. The contribution rate of nitrogen accumulated by plants with NH 4 + /NO 3 - =0:1 was the highest with nitrogen levels of 20 mg·L -1 , while plants with NH 4 + /NO 3 - =0.5:0.5 were the highest with nitrogen levels of 100 and 200 mg·L -1 . The protein, amino, and nitrate nitrogen contents in Myriophyllum aquaticum plants were all increased by increasing water nitrogen levels with a ranking of protein content > amino nitrogen content > nitrate nitrogen content. The protein concentrations in plants with NH 4 + /NO 3 - =1:0 and NH 4 + /NO 3 - =0.5:0.5 were higher regardless of water nitrogen levels, while the amino nitrogen concentration in plants with NH 4 + /NO 3 - =1:0 and the nitrate nitrogen content in plants with NH 4 + /NO 3 - =0:1 were higher than the others. It was concluded that the nitrogen removal ability of Myriophyllum aquaticum was improved by raising water nitrogen levels under the tested condition, which indicates that Myriophyllum aquaticum could purify high nitrogen wastewater. Myriophyllum aquaticum is an ammonium-nitrophile, but had the strongest capacity for growing and removing wastewater nitrogen exhibited with higher than 100 mg·L -1 nitrogen levels only with equal NH 4 + to NO 3 - . The nitrogen component concentrations of protein, amino, and nitrate in Myriophyllum aquaticum plant were all affected by the ratio of NH 4 + /NO 3 - .

Myriophyllum aquaticum , which is an important plant for constructed wetlands, has powerful purification ability for wastewater, however, the relationship between nitrogen removal ability of Myriophyllum aquaticum and wastewater nitrogen concentrations is still unclear. In this study, pot culture experiment was conducted to investigate the effect of wastewater nitrogen levels on nitrogen removal ability of Myriophyllum aquaticum . 7 nitrogen levels were set up as following:2, 5, 10, 20, 100, 200, 400 mg·L -1 . The results showed that when the wastewater nitrogen concentration was not higher than 20 mg·L -1 , Myriophyllum aquaticum with 20 mg·L -1 of nitrogen concentration grew best in the first 3 weeks; the removal rates of total and ammonia nitrogen were nearly 100% after one week, while the nitrate nitrogen concentrations were very low and varied little; the nitrogen contents of Myriophyllum aquaticum had no significant change, the upper part nitrogen content was higher than the underneath, Myriophyllum aquaticum could also remove nitrogen from the sediment. When wastewater nitrogen concentrations were 100-400 mg·L -1 , Myriophyllum aquaticum with 200 mg·L -1 of nitrogen concentration grew best from 4th to 5th week; the removal rates of total nitrogen were 76.5%, 71.5% and 48.1% in the three treatments, and the removal rates of ammonia nitrogen were 99.6%, 99.3% and 60.2% respectively, while the removal rates of nitrate nitrogen were all about 50% and there was no significant difference among treatments; the nitrogen contents of Myriophyllum aquaticum increased with nitrogen levels, but the difference between upper part and underneath was not remarkable, showing uniform distribution; nitrogen accumulations by Myriophyllum aquaticum and sediment accounted for 27.9%-48.4% and 12.2%-24.4% of total nitrogen loss in wastewater. Therefore, the nitrogen removal ability of Myriophyllum aquaticum should be inhibited by higher wastewater nitrogen level, the ammonia nitrogen removal rate was significantly higher than nitrate, the mechanism of Myriophyllum aquaticum nitrogen accumulation and distribution should also be affected by wastewater nitrogen level, and further research is needed.

Abstract: The rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo solution cultivation at seedling stage to investigate the effects of selenite addition on the selenium (Se) absorption and distribution, root morphology and physiological characteristics of rape seedlings. The results showed that the bioaccumulation ability of Se decreased significantly with increasing the Se application rate, but the Se distribution coefficient remained around 0.9 with no significant influence. The application of 10 µmol . L-1 selenite stimulated the growth of rape seedlings through improving the root physiological characteristics and root morphology significantly, including significantly increasing the production of superoxide radical (O2∙-) rate and the activities of superoxide dismutase (SOD), peroxidase (POD) and fungal catalase (CAT) in the root system, which resulted in a reduction of the lipids peroxidation (MDA) content as much as 26.0%, consequently increasing the root activity as much as 17.4%. The promoting degrees of selenite on root morphological parameters were from strong to weak in such a tendency: root volume > total surface area > number of root forks > total root length > number of root tips > average diameter. However, such positive effects had no significant difference with those in treatment with 1 µmol . L-1 selenite, indicating that small amounts (≤ 10 Lmol . L-1) of selenite were able to increase the activity of antioxidant enzymes and reduce the content of MDA in root system, which could increase root activity and improve root morphology, hence increased the biomass of rape seedlings.

The high-quality, high-yield rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo seedling stage soil cultivation and solution cultivation. This study was aimed to investigate the effects of sulfur (S) on the fraction and species of amend selenium (Se) in soil by applying S fertilizer, and to reveal the mechanism through which S controls the Se uptake of rape. The results showed that applications of both Se at 5 mg.kg-1 and S at 150 mg.kg-1 could provide some boost to rape growth, however such boost was unremarkable; S application could significantly reduce Se content in shoots and roots by as much as 64. 0% and 39. 1% , respectively; S application could significantly decrease the pH value and increase the organic matter content by as much as 0. 65 units and 1.76 g.kg-1 , respectively; S application could significantly decrease soluble Se and Fe/Mn oxide-bound Se, and significantly increase organic matter-bound Se, however, there was no remarkable effect on exchangeable and residual Se. S could significantly decrease the content of Se(IV) in the soluble Se and significantly increase the content of Se(IV) in the exchangeable Se, with remarkable decrease in Se(VI) content in both fractions, and no remarkable effect on Se(II). S had a profound effect on the uptake of Se by rape seedlings when Se( IV) and Se( VI) were applied. The Se contents in shoot and root of the Se( VI)-treated rape were 7.3 and 3.2 times respectively as high as that of the Se( IV)-treated rape, while with a S rate of 2 mmolL-1, their Se contents were lower than 32.6% and 8.7% of that of the Se(IV)-treated rape. In conclusion, in addition to improving crop growth, appropriate amount of S fertilizer could also reduce soil pH and increase organic content, causing available Se in soil to be Fe/Mn oxide-bound and organic matter-bound, and retarding its transformation to Se( VI), thus reducing Se uptake by rape. This has significant value for regulation of Se content in crops from Se-rich regions, ensuring food quality and safety, benefiting the long-term use of soil Se resources and regional economic development.

Undisturbed soil monolith lysimeter was used to investigate the effectiveness of DCD (dicyandiamide) in reducing N2O emissions in vegetable (Chinese cabbage and pepper) field. Results showed that DCD significantly reduced total N2O emission in vegetable field. Total N2O emissions from the urea treatment without DCD reached 0.215 kg x hm(-2) for Chinese cabbage, and it reduced to 0.109 kg x hm(-2), equivalent to a 49.3% reduction. The total N2O emissions for pepper were much higher compared with those for Chinese cabbage. The total N2O emitted from the urea treatment was 2.32 kg x hm(-2) (without DCD) and it was reduced to 1.14 kg x hm(-2) with DCD application, representing a 50.9% reduction. In the control treatments where no urea was applied, the daily N2O flux was very low and it never exceeded 9 microg x (m2 x h) (-1) for Chinese cabbage and 22 microg x (m2 x h) (-1) for pepper, respectively, but DCD also reduced N2O emissions (33.5% for Chinese cabbage and 33.4% for pepper). In addition, the urea-N emission factor (EF) was 0.15%, 0.99% for Chinese cabbage and pepper without DCD, respectively, and it was reduced to 0.07%, 0.52% when DCD was applied. These results demonstrated the potential of using nitrification inhibitors (DCD) to mitigate N2O emissions in vegetable system.

Objective: To probe and systematize the ancient cauterization with pyropuncture needle for evacuation of pus., Methods: One hundred and eight cases of body surface abscess were randomly divided into 2 groups. The cauterization group (n=84) were treated by drainage with electric cauterization and the incision group (n=24) by drainage with incision. Clinical therapeutic effect, the healing time and the scar area of the wound were compared between the two groups., Results: All of the patients in the two groups were effective with a similar therapeutic effect (P > 0.05); the cauterization group in the healing time and the scar area of the wound was superior to the incision group (P < 0.05)., Conclusion: Electric cauterization for evacuation of pus has advantages of rapid healing and small scar area of wound.

The study with pot experiment showed that under the stress of low soil moisture content, the oilseed rape cultivars with high and low boron (B) use efficiency had a higher fresh mass per plant at their seedling stage under high B supply, compared with those under low B supply. The increment was 43.1% and 31.7%, respectively, but no significant difference was observed between the cultivars. Under two B supply levels, the bound water content and semi-bound B distribution proportion in the leaves of the cultivar with high B use efficiency were 11.4% and 1.7%, and 6.9% and 23.8% higher than those of the cultivar with low B use efficiency, respectively. Under normal soil moisture condition, high B supply induced an increase of fresh mass per plant by 11.1% for the cultivar with high B use efficiency and by 27.4% for the cultivar with low B use efficiency, compared with low B supply. Under these two B supply levels, the cultivar with high B use efficiency had a higher content of free water in its leaves, and its leaf free B content was 2 times as much as that of the cultivar with low B use efficiency, which would benefit the B transportation in plant.

9 kinds of substrate materials (gravel, aluminite stone, sands, soil, zeolite, ceramic granule, limestone, steel slag and vermiculite) were selected to examine the phosphorus adsorption and removal capacities from runoff by adsorption, captive test and dynamic adsorption experiments. The results showed that these substrate materials had higher removal efficiency for PO4(3-) than those of other phosphorus forms. The adsorption characteristics of the substrates could be described by both Freundlich and Langmuir adsorption isotherms. The equilibrium adsorption capacity of these substrates was in the following order: zeolite, soil and vermiculite > ceramic granule, steel slag and limestone > gravel, sands and aluminite stone. The dynamic adsorption capacity was zeolite, soil, limeramic granule, limestone > steel slag, gravel and sands > ceramic granule and vermiculite. In the meanwhile, the releasing phenomena of phosphorus also could be observed in the captive and dynamic test, particularly for vermiculite, ceramic granule and steel slag. In the dynamic adsorption experiment, the removal efficiency of P-pollutants was ranged from 30% to 87% for the substrate materials except vermiculite, ceramic granule and steel slag. The results suggest that zeolite, limestone and soil are appropriate substrates for removing P-pollutants from stormwater.

An off-line filtering ditch-pond system for controlling storm runoff pollution in urban tourist areas was developed, which could retain the first flush effectively, resulting in the decrease of pollutant concentration and suspended solid average grain size, and the improvement of pollutant retention in runoff. This system could be an effective treatment system for storm runoff pollution, particularly for the scarcity of available land use in urban areas. In 2005, the yearly retention rates of TSS, COD, TN and TP were 86.4%, 85.5%, 83.9% and 82.9%, and during a storm event on June 26, the retention rates of runoff volume, TSS, COD, TN and TP were 67.9%, 97.0%, 89.2%, 94.9% and 96.2%, respectively. This system could also retain most of the suspended solids in runoff.

Most of the important economic traits in higher plants are quantitative traits. Genetic basic researches for quantitative traits were strongly promoted. This article fully elaborated the complicated relationship between quantitative phenotype and its genotype, introduced the recently developed strategy of fine mapping. discussed the current difficulty and hardness among the process of dissect the genetic basis of target traits, then brought forward several research direction that remained to be improved , and finally gave a view of such prospect. Generally speaking,, however, a QTL is still a considerable DNA fragment frequently containing multiplex genes. We also provided some ways and means from QTL coarse locus research to the variation at quantitative trait gene (QTG) level and from QTG to quantitative trait nucleotides (QTN) corresponding to alleles resulted from the intragenetic polymorphism. This is a major challenge for quantitative genetics in the post-genome era.

Effects of molybdenum (Mo) on antioxidative defense system and membrane lipid peroxidation in leaves of winter wheat (Triticum aestivum H. var. Huamai 8) were investigated under low temperature stress. Results of experiments indicate that Mo application in winter wheat induced a dramatic decrease in electrolyte leakage and malondialdehyde content under low temperature stress. The activities of antioxidative enzymes such as superoxide dismutase (SOD, EC 1.15.1.1), peroxidase (POX, EC 1.11.1.7) and catalase (CAT, EC 1.11.1.6) were increased by Mo application and the extents of increase at low temperature were higher than those at normal temperature. Mo application also caused a significant increase in the ascorbic acid (AsA) and proline contents both at normal and low temperature and following the low temperature stress the increases in ascorbic acid and proline contents in Mo-treated winter wheat were higher. There was no significant difference in carotenoid (CAR) content between with and without Mo treatment under normal temperature, while there was a significant increase in Mo treatment under low temperature stress. It could be speculated that Mo application enhanced cold resistance by increasing the capacity to scavenge active oxygen species and alleviating membrane damage in winter wheat under low temperature stress.