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【Objective】 Nitrogen fertilizer is essential to maintaining crop growth and yield, but its excessive or insufficient application has been a problem facing rice production in China. The purpose of this paper is to investigate the effect of soluble amino acid fertilizers (CWSF) on growth and yield, as well as nitrogen absorption and utilization of the rice. 【Method】 The experiment was conducted in 2018 at a water-saving irrigated rice field. In terms of nitrogen, we compared three CWSF treatments with nitrogen applied at 244 kg/hm2 (CWSF244), 214 kg/hm2 (CWSF214) and 184 kg/hm2 (CWSF184), respectively. The control was traditional fertilization used by local farmers (CF). CWSF in each treatment was applied with irrigation at different fertilization rates. During the experiment, we measured rice growth and yield, as well as nitrogen uptake by the crop. 【Result】 There was no significant difference in canopy height, tiller numbers and chlorophyll content between CWSF and CF. CWSF fertilized less nitrogen than CF, but did not result in noticeable reductions in physiological growth index. CWSF improved the ratio of grain nitrogen uptake to total nitrogen, despite its reduced nitrogen application. Comprehensive analysis showed that CWSF214 was the minimum fertilization for increasing grain nitrogen absorption and utilization of nitrogen fertilizer without leading to a yield loss. We also found that compared to CF, CWSF214-I1 and CWSF214-I2 increased nitrogen absorption efficiency by 18.09% and 27.46%, grain nitrogen content by 13.38% and 11.41%, respectively. 【Conclusion】 Considering water saving, grain yield and nitrogen use efficiency, CWSF214-I1 and CWSF214-I2 are optimal and can be used as an improved nitrogen fertilization, combined with controlled irrigation, for rice production in the low reaches of the Yangtze River.

The Yangtze River Delta region is an important commodity grain production area in China, but has been suffering from agricultural non-point source pollution issues in recent years. This study puts forward a suggestion on promoting the construction of zero-direct discharge (ZDD) engineering for agricultural wastewater from paddy fields in the region. This suggestion is based on the field investigation, policy analysis, engineering design, and economical evaluation, which clarifies the policy adaptability and the construction importance of the ZDD engineering. At the same time, this suggestion shows the basic principles, design requirements, mode selections, investment cost, and expected ecological economic benefits of the ZDD engineering. It is expected to provide decision support for China to mitigate the non-point source pollution and enhance agricultural green development. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of estradiol on myocardial voltage-gated calcium channel α1C subunit (CACNA1C) in septic mice. Methods Estradiol benzoate was injected subcutaneously into male mice followed by sepsis induced by cecal ligation and puncture (CLP). The experimental mice were divided into 4 groups: sepsis group, estradiol-treated sepsis group, sham group, estradiol-treated sham group. 3, 6, 12, 24 hours after CLP, the mRNA level of CACNA1C in left ventricular was detected by real-time fluorescent quantitative PCR, the protein expression level of CACNA1C was detected by Western blot analysis. The expression and distribution of CACNA1C were detected by immunohistochemical staining at 12 hours after CLP. Results The expression of CACNA1C was significantly decreased in sepsis group at 6 hours and remained at this low level at 12, 24 hours. The expression of CACNA1C in estradiol-treated sepsis group did not change at 3, 6 and 12 hours, but was significantly decreased at 24 hours. Conclusion Exogenous estradiol can increase the left ventricular level of CACNA1C in septic mice.