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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil denitrification is an important pathway of soil nitrogen loss. The large amount of nitrogen fertilizer applied in agricultural production leads to the increase of soil N2O emission, and it has caused environmental problems such as the enhanced greenhouse effect. At the same time, soil denitrification is also the main way of N2O reduction, so controlling the ratio of soil denitrification products N2O/(N2O+N2) is the key to reduce soil N2O emission. Based on a large quantity of relevant researches, this paper summarized the measurement methods and influencing factors of denitrification product ratio in soil and the mechanism of biochar addition affecting soil denitrification product ratio. The results showed that there was still existing uncertainty about the effect of biochar application on denitrification product ratio, and whether biochar addition could effectively regulate denitrification product ratio and reduce N2O emission was affected by some influencing factors, such as soil physicochemical properties, biochar properties and application amount. Based on the above research status, the future prospects for improving the measurement methods of denitrification products and clarifying the quantitative effects of biochar addition denitrification products ratio and its key influencing factors were proposed. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(Objective) Aggregation is an important soil health indicator modulating many soil functions including nutrient bioavailability and carbon sequestration. It is affected by a multitude of factors. The purpose of this paper is to study the effect of irrigation and nitrogen fertilization on soil aggregation and soil organic carbon. (Method) The experiment was conducted in a winter wheat field. It consisted of two nitrogen applications: 0 (N0) and 180 kg/hm2 (N180), two irrigation treatments: sufficient irrigation (F) and deficit irrigation using 65% of the water in F. In each treatments, we measured water-stable aggregates and soil organic carbon.(Result) 1 Deficit irrigation coupled with nitrogen fertilization increased water-stable macroaggregates with diameter ≥0.25 mm. Nitrogen fertilization increased organic carbon in the top 0~30 cm soil layer by more than 3.59% when irrigation was the same, while deficit irrigation increased organic carbon in the same soil layer by more than 2.86% when nitrogen fertilization was the same. 2 Soil moisture directly affected soil carbon, explaining 83.9% of the change in total organic carbon, while nitrogen indirectly affected soil carbon, explaining 46.89% of change in the total organic carbon. 3 The direct impact of water-stable aggregates on soil carbon was negative, while its direct influence was positive.(Conclusion) The effect of nitrogen fertilization on soil aggregation was modulated by irrigation. Nitrogen fertilization combined with deficient irrigation boosted carbon accumulation in the topsoil. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to clarify the expression pattern and molecular regulation mechanism of genes related to sugar, lipid and protein metabolism in maize ear leaves under different fertilization in field conditions. [ Method] Maize cultivar 'Luyu 16' was used as the material and five treatments were set up: No fertilizer (CK), nitrogen fertilizer ( N), N + P fertilizer (NP), N + K fertilizer ( NK) and N + P + K fertilizer ( NPK). At grain filling stage, the upper part of ear leaves was harvested for transcriptome analysis using RNA-Seq techniques. The differentially expressed genes ( DEGs) under different fertilizer treatments were analyzed by Hisat2 software. [Result]GO(Gene ontology)analysis showed that DEGs related to sugar, lipid and protein metabolism were enriched in Biological process ( BP), Cell components( CC) and Molecular function( MF). Although the enriched items were the same, the number of DEGs varied under different combinations. KEGG ( Kyoto encyclopedia of genes and genomes) analysis exhibited that more DEGs were enriched in carbon metabolism, starch and sucrose metabolism, and amino acid synthesis pathways. The total number of DEGs with both I log2 FC I > 1 and P < 0. 05 involved in sugar, lipid and protein metabolism under different fertilizer treatments was 82, 29 and 84, respectively. Among them, the total number of DE Gs with I log2 FC I > 2 was 6, 24 and 17. The number of DE Gs showed the maximum in comparisons of NPvsCK and NPKvsCK but the minimum in NvsCK comparison. Further analysis of DEGs with I log2 FC I showed that these DEGs had significant differences in the expression level and expression patterns. [ Conclusion] The combined of nitrogen, potassium and phosphorus fertilizer significantly affected the transcription levels of genes related to sugar, lipid and protein amino acids metabolism in maize ear leaves. Some key genes participating in the three organic substances' metabolism were identified. The results provided molecular basis for improving the photosynthetic efficiency of maize leaves by rational fertilization in the future. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective Nitrogen in paddy soil is modulated by both rainfall and drainage, and in this paper we present the results of an experimental studies on its response to controlled drainage and deep rainfall storage. Method The experiment was conducted in 2018 in field plots at the Feidong Irrigation Experimental Station. We compared two irrigation methods: alternate dry and wet irrigation (L1), and deep rainfall storage and controlled drainage irrigation (L2 and L3). Business as usual used by local farmers was taken as the control (CK). During the experiment we measured nitrogen changes in soil water and the drainage water at the depths from 50 cm to 150 cm, and analyzed the response of nitrogen dynamics to irrigation amount, drainage amount, as well as rice yield under different water managements. Result Compared with CK, L1, L2 and L3 reduced the irrigation water by 725 m3/hm2, 1 703 m3/hm2 and 2 304 m3/hm2, and increased the rainwater utilization by 11.8%, 19.0% and 25.9% respectively. In the meantime, they also reduced the irrigation times by 13. Soil nitrogen content decreased as the soil depth increased, regardless of treatments. Compared to CK, L2 and L3 reduced the maximum total nitrogen (TN) compared to CK, and L1, L2 and L3 reduced TN pollution load by 21.3%, 26.7%, 31.5%, while no significant difference in the yield was found between them. Conclusion Increasing the upper limit of the rainfall storage and extending the interval, coupled with deep rainfall storage and controlled drainage, can effectively reduce irrigation requirement and drainage times, thereby improving rainwater use efficiency. It also reduced nitrogen pollution and can thus be used as an improved agronomic practice for rice production in paddy field. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pearl River is the property of Pearl River Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The present paper aimed to explore which proportion of nitrogen and phosphorus fertilizer combined with drip irrigation water and fertilizer integration in the Yellow River Diversion Irrigation Area can promote the accumulation and transfer of spring maize dry matter in Yinchuan Plain, and its effects on fertilizer utilization rate and yield, so as to provide a basis for the integration of drip irrigation water and fertilizer for spring maize in the Yellow River Diversion Irrigation Area. 【Method】The experiment was carried out in the Yinchuan Plain of the Yellow River Irrigation Area from 2019 to 2020. The maize variety Yinyu 274 was used as the material. The conventional application rates of local nitrogen and phosphorus fertilizers were 417 and 142.50 kg/hm². The conventional application rate of 70% nitrogen and phosphorus fertilizer was 291.90 and 99.75 kg/hm2. The conventional application rates of 130% nitrogen and phosphorus fertilizer were 542.10 and 185.25 kg/hm2. Six treatments with different proportions of nitrogen and phosphorus fertilizers were set up as T1 （N 0, P 0）, T2 （N 100%, P 70%）, T3 （N 100%, P 100%）, T4 （N 70%, P 100%）, T5 （N 130%, P100%）, T6 （N 100%, P 130%）. The effects of different ratios of nitrogen and phosphorus combined application on the dry matter accumulation, dry matter transport, grain contribution rate, nutrient utilization rate and yield of maize under drip irrigation, water and fertilizer integration were analyzed.【Result】The combined application of nitrogen fertilizer 291.9 kg/hm2 and phosphorus fertilizer 142.50 kg/hm² under the combined application of six kinds of nitrogen and phosphorus fertilizers had the best overall effect. The absorption of phosphorus and nitrogen by maize was significantly higher than that of other treatments. The nutrient requirements of maize throughout its growth period were satisfied. Compared with other treatments, the dry matter accumulation increased by 6.28%-22.90%, and the dry matter transport and grain contribution rate increased by 4.60%-11.10%. Compared with conventional combined application, nitrogen fertilizer utilization rate, phosphate fertilizer utilization rate, nitrogen fertilizer partial productivity and phosphate fertilizer partial productivity were significantly increased by 52.23%, 18.92%, 57.07% and 9.95% in T4 treatment. It can also significantly improve the corn ear formation rate, the number of grains per ear, and the weight of 100 kernels, thereby increasing the yield. The yield could be increased by 8.34%-9.95% compared with the conventional nitrogen and phosphorus application, and the maximum yield was 21 916.39 kg/hm².【Conclusion】The combined application of nitrogen fertilizer 291.90 kg/hm² and phosphorus fertilizer 142.50 kg/hm² under drip irrigation water and fertilizer integration in the Yellow River Diversion Irrigation Area can significantly increase the dry matter accumulation before and after flowering, and improve the dry matter transport, transport rate and contribution to seeds, and improve N fertilizer utilization, phosphorus fertilizer utilization and N fertilizer bias productivity, thus increasing maize yield. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the effect of physicochemical properties of rhizosphere soil on quality of Coptis deltoidea C. Y. Cheng et Hsiao and further to provide scientific basis for ecological planting of C. deltoidea. [Method] Eighteen soil physicochemical indexes and six alkaloids of C. deltoidea were determined by soil agrochemical analysis and high performance liquid chromatography (HPLC) . Meanwhile, correlation analysis and redundancy analysis were used to reveal the relationship between physico-chemical properties of soil and the accumulation of alkaloids in C. deltoidea. [Result] The total contents of 6 alkaloids in taproots of C. deltoidea that grew for two to five years old were 3. 716%, 5. 720%, 8. 552% and 8. 866%, respectively, and the contents of berberine were 1. 779%, 3. 620%, 5. 469% and 5. 706%, respectively, which indicated that the four-year-old C. deltoidea had met the harvesting standard. The correlation analysis of alkaloids and soil factors in the taproot of C. deltoidea showed that total amount of 6 alkaloids and berberine content were significantly positively correlated with available potassium (P＜0. 05), and significantly negatively correlated with nitrate nitrogen and sodium (P＜0. 01) . And a significant negative correlation was also seen between sodium and rhizobine (P＜0. 01) . There was significant negative correlation between coptidine and copper (P＜0. 05), and extremely significant negative correlation between coptidine and sodium (P ＜0. 01) . Finally, according to the redundancy analysis of alkaloids in taproot and soil factors, the contents of available phosphorus, available potassium and sodium in soil were the dominant factors affecting the accumulation of alkaloids in C. deltoidea, while ammonium nitrogen and pH were the more important factors. [Conclusion] In the process of planting C. deltoidea, high-quality soil environmental conditions can be selected from the planting source, that is, the soil with high nitrogen and potassium, low phosphorus and sodium and acidic pH can be selected. Moreover, the alkaloid content of C. deltoidea can be regulated by adding potassium fertilizer and nitrogen fertilizer, controlling the application amount of phosphate fertilizer and reducing the content of sodium in the soil. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Resources & Environment / Nongye Ziyuan yu Huanjing Xuebao is the property of Journal of Agricultural Resources & Environment Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accident occurring at the Fukushima Daiichi nuclear power plant on March 11, 2011 resulted in leakage of a large amount of radionuclides, contaminating farmlands, including rice field, in Fukushima and its neighboring prefectures. Potential contamination of the rice growing these areas by the radionuclides has thus attracted public attention. The objective of this paper is to analyze rice contamination in this region and its remediation. Literature review showed that the radionuclide that was most potential to contaminate the rice is the radioactive cesium. Among all available methods to detect radioactive cesium in rice grain, belt conveyor testers is quicker in measurement but is less accurate, while germanium semiconductor detectors is more accurate but is tedious. Rice contamination by cesium accumulation is modulated by a multitude of factors, one of which is fertilization. For example, potassium fertilizer (potassium chloride is more effective than potassium metasilicate) can reduce the absorption of the radioactive cesium in rice, while nitrogen fertilizer works in the opposite. The movement and transfer of radioactive cesium in soil was affected by its concentration, potassium content, immobilization of the cesium by soil, and the thickness of the topsoil. Apart from these, rice cultivars also affect cesium accumulation. Different methods for ameliorating rice contamination by radionuclides had been developed and tested. In paddy fields, rice contamination by cesium can be reduced by amending the soil or planting. The radioactive cesium is sportive to soil and cyanobacteria can be used to facilitate the exfoliation of top soil. Also, rice is a shallow-rooted plant and deep ploughing could bury the contaminated topsoil beyond the reach of roots so as to reduce its uptake by rice. Secondary contamination can be avoided by controlling fertilization and irrigation, and the transformation of the radioactive cesium from soil to rice can be inhibited by amending the soil with schwertmannite, zeolite and vermiculite, or by controlling fertilizer application rate and the secondary contamination. Implementation of above mitigating methods over the past few years reduced the radioactive cesium content in rice in Fukushima Prefecture to 25 Bq/kg in 2014 (the radiation level set by the Food Sanitation Act of Japan in 2012 was 100 Bq/kg). This paper has implications for constructing a database for mitigating and remediating crop contamination by radionuclides which is also relevant to food production in China. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(Objective) Bioavailable water and nutrients to crops depend not only on root architecture but also on how water and nitrogen fertilizer are applied. In this paper, we investigated the effects of irrigation and fertilization on water and nitrogen dynamics in soil of a winter wheat field under border irrigation.(Method) The experiment was conducted in a wheat field in Henan province, where changes in water and nitrogen in soil under border irrigation were measured. These data were used to validate the HYDRUS-1D model, and the validated model was then used to elucidate how a change in irrigation and fertilization modulates water and nitrogen dynamics in the root zone of wheat under border irrigation. (Result) The HYDRUS-1D model simulated water and nitrogen dynamics in the root zone well. The coefficient of determination (R2) between the simulated and measured data was greater than 0.84, with its associated RMSE and MAE less than 0.807 and 0.695, respectively. Increasing the low critical soil water content for resuming irrigation moved nitrate in the top 0~20 cm soil layer to 20~100 cm soil layer 1~2 days after the irrigation, but it did not show significant effects on ammonium dynamics in the soil. Increasing nitrogen fertilization increased nitrate and ammonium nitrogen in the 0~60 cm soil layer significantly, especially in the 0~40 cm soil, but reduced water content in the 0~40 cm soil layer. (Conclusion) The HYDRUS-1D model is able to simulate water and nitrogen movement in soil under border irrigation, and the simulated results can help to improve irrigation and fertilization management for wheat production in the studied and similar areas. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to evaluate the effects of reducing nitrogen fertilizer during Chinese milk vetch returning on photosynthetic characteristics, yield and quality of rice, to explore the potential of chemical nitrogen replacement in crop rotation of Chinese milk vetch and rice, so as to provide a scientific foundation for the production of high-quality rice.【Method】Based on years of positioning tests, a control group of no nitrogen fertilizer (CK) was used, and six treatments were set up, including conventional nitrogen application (100%N), Chinese milk vetch combined with 100%, 80%, 60% and 40% nitrogen application (marked as MV+100%N, MV+80%N, MV+60%N, MV+40%N) and no application of nitrogen fertilizer (control group, CK). Rice photosynthetic characteristics of chlorophyll content (SPAD value), net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr) were measured during the heading stage, and rice quality was measured during the harvest stage.【Result】In comparison to CK, a combination of 100%, 80%, 60% and 40% nitrogen fertilizer applied to returning Chinese milk vetch could significantly increase the SPAD value, Pn, and Gs of rice (P<0.05, the same as below). The increases were 3.53%-7.29%, 10.98%-16.43% and 4.88%-14.63%, respectively. Rice yield and protein content were also significantly increased by 24.01%-41.85% and 7.38%-18.17%, respectively. Compared with conventional N application (100%N), the SPAD value and Pn of MV+100%N treatment were significantly higher than those of 100%N treatment. However, there were no significant differences in SPAD value, Pn, Gs, Ci and Tr in MV+80%N, MV+60%N and 100%N treatment (P>0.05, the same as below). In terms of rice yield and traits, yield of MV+100%N, MV+80%N and MV+60%N treatment increased by 12.06%, 7.72% and 6.64% compared with 100%N treatment, but the yield, effective spikes, panicle length, number of grains per panicle, 1000-grain weight and seed setting rate had no significant difference with 100%N treatment. In terms of quality characteristics, there were no significant differences in milling quality, appearance quality, nutritional quality of MV+100%N, MV+80%N, MV+60%N and 100%N treatments. However, the cooking quality of MV+80%N and MV+60%N treatments were significantly improved compared with 100%N treatments. The results of correlation analysis showed that returning Chinese milk vetch could improve rice yield trait through increasing SPAD value, Pn and Gs, thus, improving rice milling quality, cooking quality and nutrition quality.【Conclusion】Chinese milk vetch combined with 100%, 80%, 60% and 40% nitrogen application can significantly improve photosynthetic indexes and increase rice yield SPAD value, Pn and Gs. Chinese milk vetch combined with 80% and 60% nitrogen application can also improve the milling quality, cooking quality and nutrition quality of rice, thus providing reference for high quality rice production. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the effects of different fertilization rates on physiological indexes and nutrient content of Taxus himalayana seedlings, and to screen the best fertilization rate for the growth and development of T.himalayana.【Method】The effects of N, P2O5 and K2O (CK,F1,F2,F3 and F4) on the growth of T.himalayana were studied.The physiological indexes of leaves, stems and roots, and the contents of organic carbon (OC), total nitrogen (TN), total phosphorus (TP) and total potassium (TK) were determined.【Result】 (i) With the increase of fertilizer application, Chla and chlb contents in leaves of T.himalayana increased gradually and reached the maximum value at F3.The carotenoid content was as follows: F1 > F2 > F3 > F4 > CK.The maximum contents of soluble sugar and soluble protein were 15.80 mmol/L and 1.22 mg/g in F3 treatment, which were significantly higher than those in CK and F1 treatment (P<0.05).Malondialdehyde content increased gradually with the increase of fertilizer application, and reached 1.38 μmol/L in F4 treatment. Therefore, in the scope of this study, F3 treatment was more conducive to the accumulation of nutrients in T.himalayana. (ii) The contents of OC, TN and TP in roots, stems and leaves increased with the increase of fertilizer application, while the contents of TK only increased in roots, and first increased and then decreased in stems and leaves; At the same fertilization level, the content of OC in stem was higher than that in leaf and root, and the content of TN, TP and TK in leaf was higher than that in stem and root. (iii) With the increase of fertilizer application, the C∶N ratio of root system increased, and F4 was 13.53% higher than CK; The C∶P ratio of root, stem and leaf were 166.01-323.68, 311.33-328.79 and 183.69-252.33, respectively, and the N∶P ratio were 2.50-5.39, 4.15-6.08 and 7.42-8.44, respectively. In view of this, the input of nitrogen fertilizer should be increased in the later fertilization experiment. 【Conclusion】 Fertilization could significantly increase the contents of N, P and K in root, stem and leaf of T.himalayana, but with the increase of fertilization, photosynthetic physiological indexes and nutrients of T.himalayana increased first and then decreased. In the range of fertilization ratio in this study, when N, P2O5 and K2O were 2.40 g, 1.80 g and 1.80 g respectively, Taxus grew better. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to clarify the relationship between rice flavor quality and nitrogen nutrient absorption and utilization, the genotypes of high nitrogen efficient and good taste value rice were selected.【Method】The excellent japonica rice varieties（strains） cultivated along the yellow area were used as the test materials, and the influence of nitrogen on different rice genotype rice quality and nitrogen absorption and utilization was studied by setting different nitrogen fertilizer levels. 【Result】The taste value of different genotypes rice showed high difference, which decreased with nitrogen application increasing. The taste value of no nitrogen fertilizer was the highest and up to 83.9. Protein and straight starches increased with nitrogen application increasing. The linear analysis showed a significant open downward parabolic relationship and was performed with the nitrogen application quantity and the taste value(r=0.998**). The milled rice rate and the whole head rice rate increased with the nitrogen amount increasing, and the chalky grain rate and the chalkiness decreased with the nitrogen amount increasing. The nitrogen use efficiency, nitrogen grain production efficiency and nitrogen harvest index differed greatly between genotypes. The excellent and high-efficient nitrogen rice genotypes represented by by xindao 89 and xinkedao 31 were generally manifested with good appearance quality and relative high nitrogen grain production efficiency, up to 56.44 kg/kg. The related analysis showed that the nitrogen grain production efficiency was significantly positively with the rice taste value and significantly negatively with the protein content. The nitrogen use efficiency was significantly negatively with the taste value, negatively with the chalky grain rice rate and chalkiness, and positively with the milled rice rate and the whole head rice rate. It showed that the taste quality of rice improved and the appearance quality decreased under the level of no or less nitrogen fertilizer.【Conclusion】The nitrogen grain production efficiency can be used as an important evaluation index of excellent quality and high nitrogen efficient rice breeding. Improving the nitrogen use efficiency may be more conducive to improving rice processing, appearance quality and rice yield level. Good quality with high nitrogen efficiency（high nitrogen grain production efficiency） and high yield with high nitrogen efficiency（high nitrogen use efficiency） can be used as important evaluation standards for excellent food taste rice breeding and high yield rice breeding, respectively. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the feasibility of reducing the amount of nitrogen fertilizer and a reasonable nitrogen reduction model under late sowing wheat in the Jianghan Plain. 【Method】 Field experiments were conducted with Zhengmai 9023 under traditional and late sowing date with three nitrogen treatments differing in ratios of basal to topdressing. The changes in wheat yield and its constituent factors and nitrogen related indicators were compared across treatments. 【Result】（i） Under the same nitrogen application rate and base-topdressing ratio, grain yield, panicle number and 1000-grain weight were significantly reduced delayed the sowing date. Reduced total dry matter accumulation during flowering and maturity under late sowing was due to the decrease in dry matter accumulation in leaves and stem sheaths; The dry matter accumulation in spike did not show significant change. The changes in dry matter accumulation at maturity were related to leaves, stem+sheaths and grain husk+spike axis. Under the same nitrogen application rate and base-topdressing ratio, the nitrogen accumulation in wheat at flowering and maturity decreased as well; Nitrogen accumulation in flowering leaves of increased under late sowing, but nitrogen accumulation in stem+leaf sheath, ripe leaves and ripe grain husk+spike axis decreased. Under the same nitrogen application rate and base-topdressing ratio, the spike formation rate and nitrogen use efficiency were significantly reduced under late sowing.（ii）Under different nitrogen fertilization treatments and the same sowing date, nitrogen fertilization can be reduced from 180 to 150 kg/hm² under late sowing with insignificant change in yield decreased by 3.33 kg/hm²（M1） and 293.34 kg/hm²（M2） in 2019—2020; 158.67 kg/hm²（M1） and 13.50 kg/hm²（M2） in 2020—2021. The reduction was much lower than that of normal sowing, and the reason was that the number of spikes and grain number per spike were stable when the nitrogen application rate was reduced from 180 to 150 kg/hm², and the 1000-grain weight increased to some extent. Further reducing the amount of nitrogen applied, the yield change under the two sowing dates did not reach a significant level. Under the same base-topdressing ratio, reducing nitrogen application rate, the nitrogen accumulation in the stem+leaf sheath and spike at the flowering stage and grain husk+spike axis were significantly reduced, but dry matter accumulation did not change significantly. Under the same sowing date and base-topdressing ratio, reducing nitrogen application rate, spike formation rate increased significantly, M1 nitrogen utilization efficiency increased significantly, and M2 nitrogen utilization efficiency remained stable. 【Conclusion】Under the conditions of continuous optimization of nitrogen fertilizer management mode, the yield of late sowing wheat under nitrogen reduction treatment was not significantly reduced compared with normal nitrogen yield, but the spike formation rate and nitrogen use efficiency were significantly improved. After a delay of 20 days, the recommended nitrogen fertilizer management model is that the ratio of base to topdressing is m（base fertilizer）∶ m（top dressing before winter）∶ m（top dressing at jointing stage）=1∶1∶1, and the nitrogen application rate can be reduced from the normal nitrogen application rate to 150 kg/hm². [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to the effects of phosphorus application rate on switchgrass growth and soil nutrients in saline-alkali soil, in order to determine the appropriate amount of phosphorus, which provided a theoretical basis for saline-alkali soil improvement and high yield and high efficiency cultivation of switchgrass in Yinbei area of Ningxia.【Method】In Yinbei area of Ningxia, switchgrass, an energy crop, was used as material to study the effects of different treatments on the growth, soil saline-alkali content and nutrient absorption and utilization of switchgrass by setting 0,30 and 90 kg/hm² of phosphorus fertilizer（expressed as P0, P30 and P90, respectively） through field experiments.【Result】At the mature stage of switchgrass, the soil salinity and alkali content in 0-100 cm soil layer of each treatment were all P0>P30>P90, and the soil organic matter, available phosphorus and alkali-hydrolyzable nitrogen contents were all P90>P30>P0. Compared with P0, P90 treatment significantly reduced the soil salinity and alkali content and increased the nutrient content. Phosphorus application contributes to the growth of switchgrass, which promoted the absorption and utilization of nitrogen and phosphorus, and improved the accumulation of aboveground dry matter. Under three phosphorus levels, soil nitrogen balance of payments were deficit, and soil phosphorus balance was surplus only under P90 treatment.【Conclusion】The comprehensive results showed that under the conditions of this experiment, 90 kg/hm² P application rate could not only ensure the good growth of switchgrass and obtain high biomass yield, but also alleviate the saline-alkali pressure, improve the soil nutrient status and maintain a reasonable balance of nitrogen and phosphorus. [ABSTRACT FROM AUTHOR]

Huang-Huai-Hai region is the major superiority area of planting industry and breeding industry in China. With the increasing attention to the rural environment problems caused by crop straw and livestock manures, it is important to analyze “raising by planting” in Huang-Huai-Hai region, realize agricultural waste comprehensive utilization, and implement green development. “Raising by planting” was the core idea of this paper. The “raising by planting” calculation methods were as follow. First, technical regulations for production of wheat-corn and field research results in Hebei, Henan and Shandong provinces were used to summarize production model of wheat-corn in Huang-Huai-Hai region. So the conventional fertilization could be defined. According to test results of researches, this paper determined the amount of partial replacement of chemical fertilizer by organic manures. At the same time, thermophilic aerobic composting was chosen as techniques of livestock manure comprehensive utilization. The untreated amount of livestock manures was calculated. Then, the quantities of different species of livestock and poultry were calculated. According to the technical regulations, the amount of nitrogenous fertilizer were 532.5, 562.5 and 575 kg/hm2 in Hebei, Henan and Shandong provinces. The ratio of partial replacement of chemical fertilizer by organic manures was 30%. So the amount of replacement were 159.75, 168.75 and 172.5 kg/hm2. At the same time, there were no influence on grain security after the replacement of chemical fertilizer by organic manures. Due to the additional application of organic manures promoted soil nitrogen leaching risk, the environmental risk assessment of nitrogen in arable farmland was used. Nitrogen input mainly consisted of nitrogenous fertilizer, organic manure converted from livestock manures, seed, straw returning, atmospheric dry and wet deposition and irrigation water. Nitrogen output mainly consisted of grain and straw. Grade of environment risk in farmland in Hebei, Henan and Shandong provinces were all medium risk. Nitrogen loss rate of thermophilic aerobic composting fromlivestock and poultry manures was 42.26%. Other calculation parameters of livestock and poultry production, such as feeding period, population structure, were defined by many research papers. So in production model of wheat-corn in Huang-Huai-Hai Region, 6 dairy cows, or 18 beef cattle, or 47 to 51 swine, 731 to 789 laying hens or 8062 to 8705 broilers per hectare were land carrying capacity. Besides, at the field scale, various factors, such as soil fertility and soil microbial, might affect the ratio of partial replacement of chemical fertilizer by organic manures. So more researches were needed in the amount of replacement. On account of medium environment risk in farmland, lowering the risks was necessary. Nitrogen input structure: 46.3% chemical fertilizer, 27.5% straw returning, 19.8% organic manure, 4.0% atmospheric dry and wet deposition, 2.0% irrigation water and 0.4% seed. So reducing straw returning was one of risk solutions. In simulation results, reducing corn stalk or wheat straw both lowered environment risk effectively. The results provide a reference for planting and raising combination in Huang-Huai-Hai region. [ABSTRACT FROM AUTHOR]

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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to select optimal coated ureas as single nitrogen application to replace conventional nitrogen application practice (preplant + side-dressing), so as to improve the utilization rate of nitrogen. Using corn variety Bayu 11 as experimental material, this paper investigated the effects of different nitrogen sources (fertilizer types) and timing of N application on the soil inorganic nitrogen, corn yield and nitrogen use efficiency. The experiment was carried out as field experiment with six treatments, including control (CK), single application of preplant conventional urea (CU1), preplant conventional urea + side-dressing at stem-elongation of corn (CU2), single application of sulfur coated urea (SCU), single application of polymer-coated urea (PCU), and single application of 50% polymer-coated urea + 50% conventional urea ( HPC ). Ammonium nitrogen and nitrate nitrogen in soil of 1 m depth was measured according to the growth stages of corn. Corn yield was measured after harvest and the nitrogen use efficiency was calculated as well. The results showed that CU1 released nitrogen at higher rates at the initial stage. Though both SCU and PCU delayed the release rate of nitrogen, nitrogen release rate of SCU was clearly higher than that of PCU at the initial stage. Corn yield followed the order: PCU>HPC>CU2>CU1>SCU>CK, the yield increased by 46.3%, 38.8%, 29.5%, 25.8% and 16.9% than CK, respectively. While the nitrogen use efficiency followed the order: PCU>HPC>SCU>CU2>CU1, which increased by 49%, 43%, 39%, 36%, 25% than CK, respectively. It was concluded that both PCU and HPC significantly increased corn yield and nitrogen use efficiency. PCU and HPC could be replaced the traditional way of nitrogen application in production. The results provided theoretical basis and reference of production application for one-time nitrogen application in black soil. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to provide theoretical basis for rational application of nitrogen fertilizer to wheat, effects of reduced application rates of nitrogen on yield and quality of wheat were analyzed in Yunnan province. [Method] Using a two-factor randomized block design, the newly bred dryland wheat varieties Yunmai 76 and Yunmai 77 were used as materials to set up a nitrogen-use efficiency experiment including 5 N application rates, namely, 300 kg/hm²(N1),240 kg/hm²(N2), 180 kg/hm²(N3) and 120 kg/hm²(N4) and no nitrogen fertilizer(N5), respectively. The related indexes of grain yield, yield components and quality under different rates were determined. The correlation between grain yield and spike number, grain number per spike and 1000-grain weight was analyzed. [Result] Under different nitrogen application rates, the yield of Yunmai 76 and Yunmai 77 decreased with the decrease of nitrogen application rates. When the nitrogen application rate decreased from 300 kg/hm² to 240 kg/hm², the yield decreased by 1.38% and 0.30%, respectively; When the nitrogen application rate decreased to 180 kg/hm²or below 180 kg/hm², the yield was significantly decreased. In terms of yield components, the number of panicles per unit area significantly decreased with the decrease of nitrogen application rate; However, the effect of nitrogen application rate on 1000-grain weight and grain number per spike was not significant. The results of correlation analysis between yield and components showed that there was a extremely significant positive correlation between yield and panicle number(R=0.92）. There was no significant correlation with grain number per spike, but a significant negative correlation with 1000-grain weight. Under the rateof N180 kg/hm² and no nitrogen application, the yield of Yunmai 77 was 10.67% and 28.87% higher than that of Yunmai 76, respectively, and the yield decrease of Yunmai 77 was much lower than that of Yunmai 76 under the same N treatment. In terms of quality, protein content and wet gluten content decreased with the decrease of nitrogen application rates, and the differences were significant; The responses of sedimentation value, stability time and formation time to nitrogen application varied with different varieties. The sedimentation value of Yunmai 76 decreased at first and then increased with the decrease of nitrogen application rate, but the nitrogen reduction rate had no significant effect on the sedimentation value of Yunmai 77. [Conclusion] Yunmai 77 is a wheat variety with tolerant low nitrogen. Considering the yield and quality comprehensively, under the experimental conditions, when the conventional nitrogen application rate in this area is 300 kg/hm², the synergistic improvement of wheat yield and quality can be realized [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)