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ABSTRACT: 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.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 11/2011; 32(11):3188-92.
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ABSTRACT: MicroRNAs (miRNAs) are non-coding RNA molecules of 21-24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation, and pathogenesis of human diseases including cancer.
We analyzed the miRNA expression profiles in 10 pairs of hepatocellular carcinoma (HCC) and adjacent non-tumorous tissue (NT) from 10 non-viral hepatitis patients, using a mammalian miRNA microarray containing whole human mature and precursor miRNA sequences.
A total of 15 miRNAs exhibited higher expression in the HCC samples than that in the NT samples, and one miRNA demonstrated lower expression in the HCC samples than in the NT samples. A total of 18 miRNAs identified valid expression only in HCC samples, with six only in NT samples. The chip results were confirmed by Northern blot analysis.
Our study may help clarify the molecular mechanisms involved in the pathogenesis of HCC, and miRNAs potentially serve as a novel diagnostic tool of HCC.
Journal of Gastroenterology and Hepatology 02/2008; 23(1):87-94. · 2.87 Impact Factor
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ABSTRACT: 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.
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban 12/2007; 18(11):2487-90.
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ABSTRACT: 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.
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban 11/2007; 18(10):2319-25.
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ABSTRACT: 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.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 10/2007; 28(10):2280-6.
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ABSTRACT: Pollution in urban zoos arises from diffuse and small point sources. However, its control has received little attention in past decades. Online and offline modes of ecological engineering technology were designed to control pollution from small point and diffuse sources in Wuhan City Zoo, China. Their characteristics and performances were investigated in sixteen runoff events from 2003 to 2005. The results showed that the two modes both improved runoff water quality and had high retention rates for water and pollutants. In the outflows, the event mean concentrations (EMCs) of total suspended solids (TSS), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were reduced by 88%, 59%, 46% and 71% for the online mode, and those were 77%, 42%, 50% and 66% for the offline mode. The annual retention rates of pollutant loads for the online mode were 94.9%-98.5% in the three study years; those for the offline mode were 70.5%-86.4%. Based on calculation, the online mode was able to store the runoff of 66.7 mm rainfall completely, and the offline mode could store that of 31.3 mm rainfall. In addition, the online mode can provide an effective way for rainwater utilization and good habitats for aquatic wildlives, and has an excellent aesthetics value for recreationsal pastimes. The offline mode can save land resources and may be an effective and economical measure for diffuse pollution control in urban areas.
Journal of Environmental Sciences 02/2007; 19(9):1067-73. · 1.66 Impact Factor
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ABSTRACT: 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.
Hereditas (Beijing) 10/2006; 28(9):1191-8.
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ABSTRACT: 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.
Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology 05/2006; 32(2):175-82.
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ABSTRACT: The highly Mo efficient winter wheat cultivar 97003 yielded more than 90% and the low Mo efficient winter wheat cultivar 97014 less than 50% under Mo deficient conditions when compared to the Mo fertilizer treatment. The mechanism of Mo efficiency, molybdenum uptake and distribution in plant parts during all growth stages, was studied with these two cultivars when grown in an acid yellow-brown earth with no Mo (CK) and added Mo (+Mo) treatments. The results showed that accumulation of Mo and dry matter in shoots of cultivar 97003 was significantly higher than those of cultivar 97014 under CK through the entire growth period. Most of Mo was found accumulated in shoots after the stem elongation stage. Only low amount of Mo was accumulated during the cold winter until stem elongation stage where severe symptoms occurred in cultivar 97014 without Mo supply, while the Mo concentration of cultivar 97003 was significantly higher, thus improved its cold hardiness. Molybdenum concentrations in spikes and seeds were very low pointing to a low Mo mobility even under Mo sufficiency. However, much more Mo was distributed in the upper leaves at stem elongation stage, in spikes in heading stage, in seeds in maturity in cultivar 97003 than in cultivar 97014 under conditions of Mo deficiency. In the efficient cultivar, the Mo distribution ratios to the upper leaves and spikes were even higher without Mo supply, suggesting that a higher phloem mobility and thus a more efficient use of Mo under Mo deficiency stress. The ability of Mo uptake and phloem-mobility are discussed and it is suggested to be the important physiological basis of Mo efficiency.
Plant and Soil 07/2002; 245(2):287-293. · 2.73 Impact Factor
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ABSTRACT: The objective is to study whether the accumulation and utilization of plant N are controlled by Mo status in winter wheat cultivars. Mo-efficient cultivar 97003 (eff) and Mo-inefficient cultivar 97014 (ineff) were grown in severely Mo-deficient acidic soil (Tamm-reagent-extractable Mo 0.112 mg kg−1) with (+Mo) and without (-Mo) the application of 0.13 mg kg−1 Mo. The accumulation and use efficiency of plant total N were significantly higher in +Mo than that in -Mo and in eff than that in ineff under Mo deficiency. N use efficiency was remarkably higher in maturity but it was forwarded to jointing stage after Mo supply, thus indicating that Mo supply promoted the N use efficiency besides N uptake and eff was efficient in N uptake and utilization. The overall activity of nitrate reductase (NR, EC 1.6.6.1) was significantly higher in +Mo than in -Mo and ratio of +Mo/-Mo was even to 14.8 at tillering stage for ineff. Activity of glutamine synthetase (GS, EC 6.3.1.2) was significantly lower in +Mo than in -Mo. Concentration of nitrate and glutamate were also significantly lower in +Mo than in -Mo, thus provided evidences for enhancing N use efficiency by Mo supply. Activities of NR and GS were significantly higher and concentrations of nitrate and glutamate were significantly lower in eff than ineff under Mo deficiency, thus indicated eff was more efficient in N reduction and utilization. It is therefore concluded that Mo could promote N accumulation and utilization in winter wheat which was directly related to NR and feedback regulated by GS. Higher Mo status also results in higher accumulation and utilization of plant N in eff.
Agricultural Sciences in China.
