Effects of biochar and dicyandiamide combination on nitrous oxide emissions from Camellia oleifera field soil.

Greenhouse gas emissions from agricultural soils contribute substantially to global atmospheric composition. Nitrous oxide (N2O) is one important greenhouse gas induces global warming. Nitrification inhibitors (NI) or biochar can be effective soil N2O emission mitigation strategies for agricultural soils. However, due to differences in crop physiological traits or agricultural management, the effectiveness of mitigation strategies varies among agricultural systems. Camellia oleifera is a woody oil plant widely grown and requires intensive N input, which will potentially increase N2O emissions. Thereby, mitigation of N2O emissions from C. oleifera field soil is vital for sustainable C. oleifera development. Besides NI, incorporation of C. oleifera fruit shell-derived biochar into its soil will benefit waste management and simultaneous mitigation of N2O emissions but this has not been investigated. Here, we conducted two studies to examine effects of biochar addition and NI (dicyandiamide, DCD) application on N2O emissions from C. oleifera field soil with different N (urea or NH4NO3) and incubation temperatures. Biochar effects on nitrification rates varied among N treatments. Biochar applied in combination with DCD further reduced nitrification rates (for urea treatment, decreased from 1.1 to 0.3 mg kg-1 day-1). Biochar addition consistently increased soil N2O emissions (for urea treatment, increased from 0.03 to 0.08 ng g-1 h-1) and their temperature sensitivity. DCD application reduced soil N2O emissions with greater reductions with urea application. In future cultivation of intensively managed C. oleifera gardens, NI should be applied to mitigate N2O emissions if biochar is added, especially when urea is used.

Temporal and spatial distributions of fine roots of different varieties of Camellia oleifera.

We examined fine root distribution dynamics at the depth of 0-40 cm soil profile for five varieties of Camellia oleifera, including "Ganwu 1", "Ganyong 5", "Changlin 4", "Changlin 40" and "Gan 447", in one year using minirhizotron technique. The temporal and spatial distribution characteristics of total root tip number (TRT), average root length density (ARLD) and average root diameter (ARD) were analyzed. The results showed that the TRT and ARLD changes of each variety were relatively stable in the second half of 2016, while there was a significant monthly fluctuation in the first half of 2017, especially for "Ganwu 1" and "Changlin 40". The TRT and ARLD of "Ganwu 1" peaked in May 2017, while the ARD of "Changlin 4" peaked in March 2017. The TRT and ARLD values of "Ganwu 1" and the ARD value of "Changlin 4" were significantly greater than those of other varieties during the whole observation period. The spatial distribution and monthly dynamics of fine roots varied significantly among different varieties of Camellia oleifera. The fine roots were mainly distributed at the soil layer of 0-20 cm for "Ganwu 1" and" Gan 447 ", but at 20-40 cm for " Changlin 4 "and " Changlin 40 ". The latter two varieties had relatively stable spatial distribution and monthly dynamics of fine roots when compared to others. In contrast, the root biomass of "Ganyong 5" was not significantly different between both soil layers despite a large spatial variation. The ARD of "Changlin 4" was significantly larger at the soil layer of 20-40 cm than that of 0-20 cm. There was no significant difference in ARD between both soil layers for other varieties. In conclusion, within the five varieties, "Ganwu 1" had the greatest biomass of fine roots, which were mainly distributed in the upper soil layer, while "Changlin 4" had the largest diameter of fine roots, which were mainly distributed in the lower soil layer.

Relationship Between Carbohydrate Antigen 125 and Coronary Artery Calcification in Patients without Known Coronary Artery Disease.

BACKGROUND This study was designed to investigate the association between serum carbohydrate antigen 125 (CA125) and coronary artery calcification (CAC) score in patients without known coronary artery disease. MATERIAL AND METHODS The study groups included 348 consecutive subjects with chest pain but without known coronary artery disease, and who underwent an estimation of CAC score in our hospital. RESULTS The clinical and laboratory characteristics of all subjects are presented according to serum CA125 concentrations tertiles. The CAC score was found to be increased in the tertiles (31.6 ±82.10, 73.3±125.6, 122.9±135.9 U/mL, p<0.001). Serum CA125 concentrations are increased in calcium-positive patients compared with calcium-negative ones (9.3±4.79 vs. 11.2±7.36, p=0.003). A positive correlation between serum CA125 and CAC score was observed (r=0.319, p<0.001) in all participants. Similarly, the serum concentrations of CA125 were found to be positively correlated with CAC score in both women and men (r=0.328, p<0.001; r=0.265, p=0.001, respectively). Multiple linear regression analysis results indicated that serum CA125 concentrations are independently related to CAC score in the study population (beta=0.173, p=0.001), and age, sex, diabetes mellitus, and high-sensitivity C-reactive protein (hs-CRP) were also associated with CAC score in multiple linear regression analysis. CONCLUSIONS Serum CA125 concentrations are correlated with CAC score in the population without known coronary artery disease, and serum CA125 may be considered as a marker to estimate CAC in the study population.

[Regeneration of transgenic Lespedeza thunbergii expressing levansucrase gene (Sac B) from Bacillus subtilis].

The Bacillus subtilis Sac B gene with the vacuolar targeting signal sequence driven by 35S promotor was transferred into Lespedeza thunbergii by Agrobacterium mediated method. Total 62 Kan-resistant plants were obtained, of which 5 plants were proved to be transgenic plants. The transgenic plants were characterized by PCR amplification, PCR-Southern hybridization and RT-PCR. The physiological assay results showed that the transgenic plants were more tolerant to stress than the controls under the condition of 200mmol/L NaCl and 5% PEG, respectively, and that the content of soluble sugar in trnsgenic plants was significantly higher than that of controls in the period of tests (5-15 days) under salt and PEG stress.