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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.)

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 Forest Engineering is the property of Forest Engineering 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 Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of 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.)

[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 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 investigate the effects of balanced fertilization on the fertility and microbial community structure of Amaranthus tricolor L. inter-root soil, to provide a reference basis for shaping a fertile A. tricolor inter-root soil microenvironment and constructing a high-yielding and high-quality A. tricolor production technology system.【Method】Based on traditional and high-throughput sequencing techniques, the study analyzed the changes of soil fertility and microbial community structure in the inter-rhizosphere of A. tricolor under the conditions of blank control(CK),potassium deficiency fertilization(NP),nitrogen deficiency fertilization(PK),phosphorus deficiency fertilization(NK) and balanced fertilization[188.0,53.0 and 50.0 kg/hm² of nitrogen, phosphorus and potassium(NPK) fertilization, respectively].【Result】Application of different ratios of N,P and K fertilizers increased β-glucosidase, aminopeptidase and phosphatase activities in A. tricolor inter-root soil; Compared with the NPK treatment, the microbial biomass carbon(C),N and P contents of A. tricolor inter-root soil were generally lower in the non-balanced fertilizer treatment; All fertilizer treatments contributed to increase the bacterial diversity and richness of A. tricolor inter-root soil, but only the balanced fertilizer treatment increased the diversity and richness of fungi in the inter-root soil of A. tricolor. At the level of bacterial phylum classification, abundance percentage of the dominant bacterial phylum Proteobacteria, Acidobacteriota, Patescibacteria, Gemmatimonadota, Bacteroidota and Myxococcota in A. tricolor inter-rhizosphere soil in all fertilizer treatments increased, but that of Actinobacteriota and Chloroflexi decreased. At the taxonomic level of bacterial genera, fertilization not only obviously changed the abundance of bacterial genera at the taxonomic level of A. tricolor roots, but also enriched some specific dominant bacterial genera(unclassified＿o＿ Saccharimonadales,norank＿ f＿LWQ8 and Sphingomonas). At the fungal phylum taxonomic level, Ascomycota, Chytridiomycota, Mortierellomycota and unclassified＿ k＿ Fungi were the dominant fungi common to all fertilizer treatments; At the taxonomic level of fungal genera, Plectosphaerella,unclassified＿ f＿ Chytridiaceae,Gibellulopsis,Phialemonium,Mortierella,unclassified＿ k＿ Fungi and Myrothecium were the dominant fungal genera in the top 10 in terms of abundance in the different fertilizer treatments and missing from CK.【Conclusion】The application of different ratios of N,P and K fertilizers helped to improve the fertility of A. tricolor inter-roots soil and create a healthy soil environment, among which the balanced application(188.0,53.0 and 50.0 kg/hm2 of N,P and K fertilizers respectively) was the most effective in increasing the abundance and diversity of A. tricolor inter-root soil bacteria and fungi and improving the microenvironment of A. tricolor inter-root soil. It can be applied in the production of A. tricolor. [ABSTRACT FROM AUTHOR]

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.)

[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]

【Objective】In order to provide a theoretical basis for the increase of yield and output value of tea and the nutrient absorption of big-leaf tea species in modern tea garden,this paper studied the effects of optimized fertilization technology on the quality of tea in modern tea garden of Pu’er.【Method】In this paper,‘Yunkang14’,an excellent tea variety,was used as the test material,and the plot experiment was carried out with treatment 1(no fertilization,CK),treatment 2(conventional fertilization),and treatment 3(Formula fertilization) and treatment 4(Optimized formula fertilization).The treatment 3 and treatment 4 had the same amount of fertilizer applied,but different fertilization methods.【Result】The accumulation of nitrogen,phosphorus and potassium in the new shoots of tea tree in treatment 4 were significantly higher than those in other treatments.The contents of phosphorus and potassium in tea shoots were significantly higher than other treatments; the agronomic efficiency of treatment 4 was 9.58 kg/kg for nitrogen fertilizer,22.99 kg/kg for phosphate fertilizer and 28.74 kg/kg for potash fertilizer,respectively,and their partial productivity was 23.14,55.54 and 69.42 kg/kg respectively.Compared with treatment 2 and treatment 3,the 100-bud weight of treatment 4 increased by 12.74 % and 2.06 %,the germination density increased by 10.84 % and 1.14 %,the fresh leaf yield increased by 15.71 % and 3.98 %,and the output value increased by 28 135 and 3224 yuan/hm2,respectively.【Conclusion】In the field experiment,the optimized fertilization technology can significantly improve the tea yield,output value and nutrient uptake of Pu’er modern tea garden.It is suggested to promote the optimized fertilization technology in Pu’er modern tea garden tea production [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 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.)

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 Journal of Southern Agriculture is the property of Journal of Southern Agriculture 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 Southern Agriculture is the property of Journal of Southern Agriculture 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】The present paper aimed order to explore the improvement effects of compound microbial fertilizer on soil nutrient content, a field test of applying compound microbial fertilizer combined with farm manure on soil restoration in karst area was carried out at the test site of Hylocereus polyrhizus（pitaya） orchard in Guohua town, Pingguo city, Guangxi.【Method】Nine fertilization treatments（T1-T9） were set up in the pitaya orchard. The soil nutrient content, microbial quantity and soil enzyme activity of each treatment were, with no fertilization and no compound microbial fertilizer as control（CK）. The effects on soil biological characteristics and soil fertility were discussed.【Result】The mixed application of compound microbial fertilizer and farm manure were able to improve the contents of soil organic matter（SOM）,total nitrogen（TN）,total phosphorus（TP）,total potassium（TK）,available nitrogen（AN）,available phosphorus（AP） and available potassium（AK）,and promote the increase of soil bacteria, actinomycetes, nitrogen-fixing bacteria and yeast, and also inhibit the growth of harmful microorganisms and fungi. The activities of soil urease, sucrase, catalase, polyphenol oxidase and acid phosphatase were enhanced. The T9 treatment provided the best improvement, as compared with CK,the contents of SOM, TN,TP,TK,AN,AP and AK increased by 65%,31%,83%,37%,62%,47% and 31%. The number of bacteria, actinomycetes, azotobacter and yeasts increased by 22%,86%,63% and 84%,while the number of fungi decreased by 49%.The activities of urease, sucrase, catalase, polyphenol oxidase and acid phosphatase increased by 51%,60%,162%,55% and 83%,respectively.【Conclusion】Applying compound microbial fertilizer with farm manure in the pitaya orchard in rocky desertification area can improve soil fertility by increasing the content of soil nutrient, increasing the number of soil bacteria, actinomycetes, nitrogen-fixing bacteria, yeasts, inhibiting the increase of fungi, and enhancing soil enzyme activity. Especially, the effect of 2.50 kg/plant farmyard manure+3.00 kg/plant compound microbial fertilizer is the best. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to the problems of shallow soil arable layer depth, soil salinization and reducing maize yield in maize fields in Ningxia Yinbei irrigation area, the effe cts of different Fenlong tillage depths on soil available nutrients and maize yield were studied to select suitable Ningxia silver the Fenlong tillage technology in the north yellow irrigation area realizes the benign production of the soil. [Method] This experiment adopted a randomized block design, with Fenlong tillage depth 40 cm ( FIAO: Tillage depth 0 - 40 cm), Fenlong tillage depth 50 cm ( FISO: Tillage depth 0 - 60 cm) and traditional rotary tillage ( CK: Tillage depth 0 - 20 cm) as a control. Soil samples were collected at different growth stages of maize to determine soil water content, pH, available nitrogen, available phosphorus, available potassium and organic matter content and maize yield under different F enlong tillage treatments variety. [ Result] The soil water content of different Fenlong tillage treatments was significantly different in different growth periods of maize compared with traditional tillage. From the emergence period to the milking period, FIAO was significantly higher than that of CK, and the highest soil water content of FIAO was 16. 99%, followed by FISO, the soil water content was 16. 86%, which was 6. 5% and 5. 8% higher than that of CK, respectively; FIAO and FISO could significantly reduce the soil pH; FIAO and FISO in the maize jointing and tasseling period had significantly higher soil available nitrogen content than that of CK, espec ially FIAO, the soil available nitrogen content increased significantly after Fenlong tillage treatment; The average content of soil available phosphorus in FIAO and Fl.SO during the entire growth period was higher than that of CK, especially Fl.SO was the most significant after Fenlong tillage treatment, and t he content of soil available phosphorus was also significantly increased after Fenlong tillage treatment ; FIAO had significantly higher soil available potassium content t han that of CK in the early period of maize growth, FIAO could effectively increase the soil available potassium content; FIAO and Fl.SO had significant soil organic matter content in both the emergence period and jointing and tasseling period higher than that of CK, and the soil organic matter content after Fenlong tillage treatment significantly increased; Among the yield components of maize kernels, FIAO and Fl.SO had a greater effects on the hundred-kernel weight, number of kernels per ear, number of ears per 6fJ7 m2 and yield of maize kernels CK increased significantly, with FIAO being the most significant, which increased by 48. 22 % compared with traditional tillage. The yield of maize was significantly positively correlated with the content of available nitrogen and available potassium in t he soil. [Conclusion] Fenlong tillage can effectively reduce soil pH and increase soil water content, thereby increasing soil available nutrient and organic matter content, also, the content of available nitrogen and available potassium in the soil are the main factors affecting maize yield and ultimately increase maize yield. Therefore, it is believed that Fenlong tillage can be used as a new agronomic measure for the saline l and of N ingxia Yinbei irrigation area. [ABSTRACT FROM AUTHOR]

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.)

[Objective] The present paper aimed to study the effect of urea-formaldehyde slow-release fertilizer rods on the growth and nutrient absorption of rubber seedlings, and provide a theoretical basis for the application of urea-formaldehyde slow-release fertilizer rods on rubber trees. [Method] Using urea-formaldehyde slow-release fertilizer with 0%,25%, 50%, and 75 % of total nitrogen as the test fertilizer, the pot experiment of rubber tree seedlings was carried out to study the effects of different urea-formaldehyde slow-release fertilizer rods on the growth and nutrient absorption of rubber tree seedlings. [ Result] When the urea-formaldehyde slow-release fertilizer rod with 50% urea-formaldehyde nitrogen was applied, the plant height and stem diameter of the rubber seedlings were the largest, which were 149. 32 cm and 17. 96 mm,respectively. But it was not significantly different from conventional fertilizer treatment. With the increase of the proportion of urea-formaldehyde nitrogen, the whole plant biomass, nitrogen absorption, phosphorus absorption, potassium absorption and fertilizer use efficiency of the rubber tree seedlings all showed as increased first and then decreased. When the urea-formaldehyde slow-release fertilizer rod with 50 % urea-formaldehyde nitrogen was applied, the whole plant biomass, nitrogen absorption, phosphorus absorption,potassium absorption and fertilizer use efficiency of the rubber tree seedlings were the largest. [Conclusion] It is most beneficial to the growth of rubber seedlings and nutrient absorption of rubber tree seedlings when the urea-formaldehyde slow-release fertilizer rod with 50% urea-formaldehyde nitrogen. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01 ). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [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.)

[Objective] The present paper aimed to study the optimum fertilizer on tobacco cultivation, which would provide a theoretical basis for the reasonable fertilizer application of tobacco leaves in Liangshanyi autonomous prefecture. [Method] Taken Yunyan 87 as tested materi als, the effect of different fertilizer ratios of nitrogen ( N), phosphorus ( P) and potassium ( K) on the leaf biomass, quality components and Cd accumulation of Nicotiana tabacum were studied by pot assay. [ Result]The fertilizer application could not only promote the growth of to bacco and increase the leaf biomass, but also had a positive effect on the accumulation of quality components and the coordination of qnalitative proportion. The contribution efficiency of nitrogen, phosphorus and potassium to plant height and leaf biomass of tobacco was N > P > K. Potassium fertilizer played an important role in the accumulation of potassium in tobacco leaves. The contents of nicotine and total nitrogen were significantly increased, and the coordinated proportion of qnality components was presented under the high level of nitrogen fertilizer. Cd content was an important index to evaluate the qnality and safety of tobacco leaves. The content of Cd in tobacco leaves was in the order of lower leaves > middle leaves > upper leaves. Meanwhile, the abilities of Cd absorption and accumulation of tobacco plants to soil were sig nificantly improved with the high level of combined nitrogen and phosphorus fertilizer, nd storage in tobacco leaves, however, there was no notable influence for potassium fertilizer. [ Conclusion] In summary, the best fertilizer recommended by this pot assay was the treatment of N212K2,when the ration ofN: p: K was 1:0.45:2. 06, average plant height and leaf biomass were 79. 2 cm and 55. 2 g; With 3. 22%,3. 05%,3. 76%,25. 89% and 27. 74% for the content of potassium, nicotine, total nitrogen, reducing sugar and total sugar, respectively, the ratio of sugar and nicotine and the ratio of sugar and nitrogen were 9. 10 and 7. 38, respectively; The Cd contents of lower leaves, middle leaves and upper leaves were 1. S7, 1. 37 and 1. 11 mg/kg, respectively, which was statistically lower the limit level of 3. 0 mg/kg prescribed by the China Tobacco Corporation. It was suggested that this fertilization scheme could be widely applied in various tobacco areas and similar producing areas of Liangshanyi autonomous prefecture. [ABSTRACT FROM AUTHOR]

(Objective] The purpose of this paper was to study the effects of buse and topdressing with different potassium-rich soil conditioners on tobacco production during the period of soil cultivation. [ Method ] In this study, wood peat derived potassium humate, mineral potash (hydrothermal method) and calcium magnesium phosphate fertilizer were used instead of KNOW, or K, SO, on the base, to study their effects on soil pH, available potassium, slow potassium, tobacco leaf quality and economic status of flue-cured tobacco. [ Result ] The results showed that base and topdressing different potassium-rich soil conditioners could effectively improve soil pH of tobacco root zone and keep it between 5.5 -6.5. The effect is as follows T5 > T3 > T4 > T2 > TI, among which wood peat derived potassium humate (base fertilizer) and calcium magnesium phosphorus fertilizer had the best effect; Topdressing wood peat derived potassium humate, mineral potash (hydrothermal meth od) and calcium magnesium phosphate fertilizer could significantly improve available potassium, slow potassium content of soil and the pro portion of middle, upper leaves'. Among them, woody peat derived potassium humate (basie fertilizer) and mineral potassium fertilizer (hydrothermal method) had the best application effect at 1:3. Compared with the control, the content of available potassium was increased by 60.95 % (0 - 10 cm),77. 78 % (20 -40 cm), the content of slow-acting potassium was increased by 16. 63 % (10. 20 peat derived potassium humate, mineral potash (hydrothermal method) and calcium magnesium phosphate fertilizer could ef province, increase soil potassium storage capacity and potassi um supply capacity, the proportion of upper and middle leaves, the quality of tobacco leaves and the economic situation of flue-cured toba co. Base woody peat derived potassium humate and topdressing mineral potassium fertilizer (hydrothermal method) have the best applicatic effect at 1:3. [ABSTRACT FROM AUTHOR]

[Objective ] The objective of the paper is to provide the scientific basis for reducing chemical fertilizer and improving efficiency for vegetable in acidic yellow soil area of Guizhou. [ Method] The effects of combined application of biochar and yellow phosphorus slag on yield and nutrient uptake and utilization of Chinese cabbage cultivated in acidic yellow soil are studied by a pot experiment in green house. [ Result] The yield of Chinese cabbage under different treatments of biochar and yellow phosphorus slag combination is increased by 37.22 % - 82.07% compared with that of non-fertilization treatment, and the yield of Chinese cabbage applied with chemical fertilizer + 70 glpot biochar + 11.7 glpot yellow phosphorus slag is the highest ( 553. 5 g/ pot) . The nitrogen, phosphorus and potassium content in Chinese cabbage under different treatments of biochar and yellow phosphorus slag combination is increased by 39.9% - 57.9%, 1.31% - 35.22% and 1.99 % -39.09% respectively compared with that of non-fertilization treatment. The nitrogen, phosphorus and potassium uptake of Chinese cabbage under different treatments of biochar and yellow phosphorus slag combination is increased by 107.8% - 188.9%, 65.89% - 128.82% and 61.73 % - 122.97% separately. Except there is no obvious difference in phosphorus uptake of Chinese cabbage applied chemical fertilizer + 18.0 glpot yellow phosphorus slag and non-fertilization treatment, the nitrogen, phosphorus and potassium uptake of Chinese cabbage under other treatments of biochar and yellow phosphorus slag combination is higher than that of nonfertilization treatment significantly. Among various fertilization treatment, chemical + 70 glpot biochar + 11.7 g/pot yellow phosphorus slag has the highest nitrogen and phosphorus utilization efficiency, respectively 59. 01 % and 8. 83 %, while chemical fertilizer+ 100 glpot biochar + 9.00 glpot yellow phosphorus slag has the highest potassium utilization efficiency, which is 92. 10 % . [Conclusion ] Rationally combined application of biochar and yellow phosphorus slag can improve yield, nutrient uptake and utilization of Chinese cabbage, and low amount of biochar combined with high amount of yellow phosphorus slag has the best effect. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore suitable water and fertilizer integration with reduced fertilization mode for flue-cured tobacco production on slope land in southern tobacco-growing areas [Method] Taking the local conventional water and fertilizer management as a comparison, the effects of water and fertilizer integration on dry matter accumulation, N and K absorption and distribution, fertilizer utilization rate and soil nutrient balance of Hue-cured tobacco on slope land were studied. [ Result] Results of two-year experiment showed that the dry matter accumulation, nitrogen and potassium absorption of flue-cured tobacco with water and fertilizer integrated management were still higher than those of control when fertifu.er was reduced, and fertilizer utilization ratio significantly increased, and the nutrient surplus and balance coefficient were reduced. T2 treatment with 20 % reduced fertilization increased the dry matter accumulation by 22. 28 % in maturing stage than that of conventional treatment, and promoted the absorption of nitrogen and potassium by 92. 64 % and 83. 23 % respectively in root extending stage. The apparent utilization rate, season recycling rate and economic utilization rate of nitrogen fertilizer of T2 treatment increased by 20. 98 %, 14. 6 % and 8. 6 % respectively compared with CK, even 15. 25 %, 16. 15 % and 17. 64 % higher than Tl treatment with the same amount fertilizer. Fertilizer productive efficiency of potassium increased by 35. 02 % on average, and the biggest difference of apparent utilization rate, season recycling rate and economic utilization rate between T2 and CK appeared in 2017, reaching 80. 62 %, 105. 6 % and 126. 03 % . From the soil nutrient balance, water and fertilizer- integration mode increased crop carrying capacity and reduced nutrient surplus. Compared with CK, T2 and T3 treatments reduced nitrogen surplus by 49. 3 and 54. 6 kg • hm -2, and the nutrient balance rate decreased 93. 85 and 103. 16 percentage points. The best performance on potassium balance was T2 treatment, it's potassium surplus decreased by 86. 69 kg·hm-2 compared with CK, and the balance rate fell 158. 75 percentage points. [ Conclusion] In conclusion, under the water and fertilizer integration mode, it can improve the fertilizer utilization rate and reduce the soil nutrient surplus by properly reducing the fertilizer consumption and increasing the topdressing ratio. [ABSTRACT FROM AUTHOR]

( Objective) The present paper aimed to solve at the deterioration of soil physical properties and decline of soil fertility by irrational fertilization in northern Liaoning province, and the effects of different fertilization treatments on soil physicochemical properties and spring maize yield in northern Liaoning province were studied. [Method] Successive 2 year field experiments were conducted in the main maize production area in the northern of Liaoning. Five different treatments with mixed chemical and organic fertilizers no nitrogen with chemical P and K ( CK),conventional fertilization( CK1), optimize fertilization(T1), organic manure combined with chemical fertilizer(T2), and humic acid combined with chemical fertilizer( T3) with three replications were examined. The soil bulk density, soil nutrients, maize yield and yield components of each treatment were compared. [Result] The humic acid and organic mature combined with chemical fertilizer could reduce soil bulk density, compared to conventional fertilization treatment, decreased soil bulk density by 2. 97 % and 3. 94 %, 1. 22 % and 3. 08 %, 2. 67 % and 3. 60 % in 5 -10, 10 - 15 and 15 - 20 cm of soil layers. Compared to conventional fertilization, applying humic acid and organic manure could significantly improve soil fertility, increased organic matter by 2. 38 % and 2. 98 %, alkali-hydrolyzed nitrogen by 5. 69 % and 9. 82 %,available phosphorus by 14.47 % and 19. 60 % and available potassium by 8.07 % and 7. 92 %. The maize yield of humic acid and organic manure treatment was higher than that of the conventional fertilization treatment, respectively, increased by 950 and 852 kg/hm 2 • (Conclusion ) The comprehensive analysis results showed that the measures of suitable fertilization in northern Liaoning province was that the amount of humic acid was 600 kg/hm² or organic mature was 1500 kg/hm² while the nitrogen application was 198. 9 kg/hm². [ABSTRACT FROM AUTHOR]

[Objective] The effects of different nitrogen and potassium application amounts on NK nutrition utilization and yield of rapeseed on different soil types in rapeseed-tobacco rotation area was studied. The purpose of this paper was to provide theoretical basis and technical support for precision nutrient management and reducing chemical fertilizer of rapeseed production. [ Method] Field trials were carried out in 3 kinds of soil type to investigate yield and nutrition utilization of rapeseed with different nitrogen and potassium application amounts. Egression equations of the quadratic model between N and K application amounts and N and K nutrition utilization of rapeseed were established. The effects of different nitrogen and potassium application amounts on different soil types on yield of rapeseed was analyzed. [ Result] Yield of rapeseed with N 90 kg/hm² was the highest in red soil. Yield of rapeseed with N 180 kg/hm² was the highest in paddy soil. Yield of rapeseed with N 270 kg/hm² was the highest in sandy loam. The yield increasing effect of N was sandy loam > paddy soil > red soil. Contribution of N to yield was red soil > paddy soil > sandy loam. In red soil, nitrogen use efficiencies of rapeseed with N 90,180 and 270 kg/hm² was 63. 68 %,31. 53 % and 18. 59 % respectively. In paddy soil, nitrogen use efficiencies of rapeseed with N 90,180 and 270 kg/hm² was 54.95 %,42. 5 % and 29. 45 % respectively. In 8&l'ldy loam, nitrogen use efficiencies of rapeseed with N 90,180 and 270 kg/hm² was 31. 95 %,37. 14 % and 33. 29 % respectively. There was no significant difference in yield of rapeseed between treatment with K and no K. In paddy soil and in sandy loam, yields of rapeseed with K SO kg/hm² was higher than other treatments. The yield-increasing effect of K was red soil > paddy soil > sandy loam. Contribution of K to yield was red soil > paddy soil > sandy loam. In red soil, K use efficiencies of rapeseed with K 50, 100, 150 kg/hm² was 46. 52 %,30. 2 % and 28. 18 %, respectively. In paddy soil, K use efficiencies of rapeseed with K SO, 100, 150 kg/hm² was 38. 91 %,22. 89 % and 19. 61 %, respectively. In sandy loam, K use efficiencies of rapeseed with K 50, 100, 150 kg/hm² was 55. 6 %,31. 29 % and 18. 39 %, respectively. [ Conclusion] In red soil of Luoping City, application amount of N and K on rapeseed production should be reduced. In paddy soil of Chengjiang City, application amount of K on rapeseed production should be controlled. In sandy loam of Tengchong City, application amount of N on rapeseed production should be increased and application amount of K on rapeseed production should be controlled. It was important that different nutrient management strategy should be adopted on different soil types in different area. [ABSTRACT FROM AUTHOR]

【Objective】Through the comparison of models, the present paper aimed to explore the influence of ’chninese milk vent Returning to the Field coupled with rice and fish symbiosis’ on the soil nutrients and yield of rice, and provided a scientific basis for efficient and high-quality rice production and sustainable development.【Method】In this experiment, four treatments including conventional rice planting as a control(CK), chninese milk vent Returning to the Field(ZD), rice and fish symbiosis(YD),chninese milk vent Returning to the Field coupled with rice and fish symbiosis(ZY), measuring, analysis and comparison of the contents of soil nutrients(organic matter,total nitrogen, total phosphorus,total potassium and their effective state), rice yield and yield component index of each treatment were performed.【Result】Compared with CK, YD, ZD and ZY can effectively improve the soil fertility of rice in the current season, and ZY has the best effect. Compared with CK, soil organic matter, total nitrogen, total phosphorus, total potassium and their effective state content of ZY mature period were increased by 16.40 %, 18.18 %, 20.63 %, 3.42 %, 7.71 %, 15.96 % and 1.85 %(P<0.05); ZD can effectively alleviate soil acidification, and the soil pH at maturity was 6.06,which compared with CK, YD and ZY, it increased by 0.04, 0.12 and 0.08 units, and the difference was significant(P <0.05);Compared with CK,ZY, ZD, and YD can increase the yield of rice in the season effectively, and ZY has the highest yield of rice, reaching 6.29 t/hm~2. Compared with CK, ZD and YD, the actual yield of ZY increased by 4.83 %-11.33 %,and the difference was significant(P <0.05).【Conclusion】In summary, chinese milk vent returning to the field coupled with rice and fish symbiosis can effectively improve soil fertility and significantly increase rice production in the current season, which was an greenand efficient way of fertilizing. [ABSTRACT FROM AUTHOR]

[Objective] The objective of the paper is to provide the scientific basis for rational fertilization in Jianhe County of Guizhou Province and similar areas. [Method] The effects of soil nutrient indexes(total N .organic matter, available N .available K, available P, total P and total K)on soil fertility are explored by using variation coefficient method, correlation coefficient method and weighted mean method, and then the soil fertility in paddy field and dry' land is evaluated by using improved Nemerow comprehensive evaluation method combined with the weight coefficient mean value of the three methods. [Result] The soil available k in paddy field and total P in dry land were at a lower level, while other nutrient indexes were at a medium-high, high and higher level. The soil available N content in six dry' land sampling sites with different plants was high. Soil total P and available k fluctuate greatly among sampling sites, while organic matter content fluctuates less. The soil available P in fertility factor weighted coefficient of paddy field and dry land was the highest, respectively 0. 2710 and 0. 2358 comparing the mean value of the three weighted method weighted coefficient. The available P is the main factor influencing soil fertility in paddy field and dry' land and soil fertility indexes is 1.52 and 1.63 separately. The soil comprehensive fertility was at a fertile level. [Conclusion] The soil fertility of paddy field and dry land in Jianhe County is at a fertile level, and available P is the main factor influencing soil fertility in paddy field and dry land. The soil N content in paddy field and dry land is high, which can meet the demand of crop production. Therefore, N fertilization should be reduced in production. The soil K content in paddy field is low, and the corresponding fertilization measures should be taken to improve K supply level in paddy field. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to provide theoretical basis for the rational application of potassium and chlorine fertilizer in the flue-cured tobacco production in Yunnan raw material base of Yunyan brand.【Method】 1130 soil samples from 37 counties of Kunming, Qujing, Honghe, Baoshan, Wenshan were used as materials to determine the content of potassium and chlorine in tobacco samples. The characteristics of potassium and chlorine ratio in different regions, main varieties, soils at different altitudes and tobacco leaves in Yunnan raw material base of Yunyan brand were analyzed. The potassium chlorine ratio of tobacco leaves was regionalized by ArcGIS. 【Result】The results showed that the samples with potassium chloride ratio more than 10 % were the most, accounting for 43.2 %; The samples with potassium chloride ratio between 4.0 % and 6.0 % were the least, accounting for 11.7 %. Qujing had the largest number of towns with low K/C ratio(< 4 %) and Wenshan had the smallest; Qujing had the largest number of towns with high K/C ratio(> 10 %), while other cities had the same number. The main cultivar with the highest mean of K/C ratio in middle tobacco leaves was Yunyan 85, which was 14.41; The lowest was Yunyan 97, which was 7.30; The others were between 8.44 and 12.73. The highest mean of K/C ratio of middle tobacco leaves in different altitude areas was 11.72, which was mainly distributed in the altitude area of 1100-1400 meters; The lowest was 8.91, which was mainly distributed in the altitude area of 2000-2300 meters. 【Conclusion】In order to production of high-quality flue-cured tobacco in Yunnan raw material base of Yunyan brand, areas with high K/C ratio of tobacco leaves in Kunming, Qujing, Honghe, Baoshan and Wenshan could be selected. K326, Yunyan 87, Yunyan 85 and other high efficient flue-cured tobacco varieties for potassium accumulation and utilization could be selected. It could be planted at the altitude of 1100-2000 meters. [ABSTRACT FROM AUTHOR]

[Objective] This paper aims to provide optimal fertilization guidance for high-yield cultivation of P. frutescens and promotion of new P. frutescens varieties. [ Method] The effects of nitrogen, phosphorus and potassium fertilizers on the yield of two new P. frutescens varieties ( Qisu 2 and Qisu 3) were studied by ternary quadratic orthogonal rotation design. The regression equation and model analysis were constructed to optimize the high-yield fertilization mode. [ Result] N was the most important factor influencing the yield of P. frutescens. However, the two varieties varied in response to P and K fertilization. The regression models of nitrogen (x1) , phosphorus (x2) and potassium (x3) of the yield (Y) are Y = 2219.384 + 405.410x1, +304.926x2 - 156.723x12 -78.676x22 - 214. 479x1x2, and Y =2048.806 + 319.535x1, +54.722x3 -63. 102x12 - 113. 664x22 +76.017x32 -69.069x1x2, respectively. The best fertilization ratio of N, P and K fertilizer was (286.022 ±25.288),(139.059 ±20. 819),(180. 000 ± 35. 860) kg/hm2 , and (338. 180 ± 16.617) , (80. 923 ±21.314) , (203.529 ± 24. 278 ) kg/hm2, respectively. The yield of P. frutescens could reach 2250 kg/hm2. [ Conclusion ] Compound application of NPK fertilizers functioned significantly in enhancing P. frutescens yield. [ABSTRACT FROM AUTHOR]

[Objective]This paper aimed to study the selenium contents in soil and tea leaves at different planting year tea trees( la, 5a, 10a, 15a). [ Method] Field sample investigation and indoor analysis method were measured. [ Result] (i) The crown, stem and branch of tea trees increased and tree density decreased with increasing planting age. (ii) Soil nutrients (Organic carbon, total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus and available potassium) first increased and then decreased from 1 to 15 years of tea trees, which showed 10 a > 15 a >5 a > 1 a. (iii) Water extract, tea polyphenols, caffeine and free amino acids first increased and then decreased from 1 to 15 years of tea trees, which showed 10 a > 15 a >5 a > 1 a. (iv) Total selenium content, total selenium enrichment coefficient and effective total selenium enrichment coefficient in soil and tea first increased and then decreased from 1 to 15 years of tea trees, which showed 10 a > 15 a >5 a > 1 a. (v) Correlation analysis showed that the total selenium content in soil was significantly positively related with soil nutrient, and there was the correlation of the tea full selenium and effective selenium with soil physical and chemical properties but not significant (P > 0.05). [ Conclusion ] The main influencing factors for soil selenium were organic carbon (load coefficient was 0. 689) and total nitrogen (load coefficient was 0.702) , and the main influencing factors for the selenium of leaves were the water extract of tea ( load coefficient was 0. 623 ) and tea polyphenols (load coefficient was 0.726). [ABSTRACT FROM AUTHOR]

[Objective] The aim of this paper was to provide a theoretical relerence for the application of loss-control urea in rice production in yellow soil. [Method] Based on the same application rates of phosphorus and potassium fertilizer, the rice cultivar Leyou 58 was employed to explore the ellects of loss-control urea, with various adding amount of loss-control agent (1 %,2%,3%,4%,5%,6%), on rice yield, nutrients uptake and utilization. Meanwhile, no nitrogen and common urea fertilizer were taken as the controls. [Result] No regular changes of rice yield observed with increasing the dosage of loss-control agent, while the accumulation of nitrogen in rice grain, nitrogen, phosphorus and potassium in rice straw, and potassium in aboveground parts showed regular variation. At the same time, regular changes were also observed on rice nitrogen, phosphorus, potassium harvest index and potassium absorption efficiency. Compared with common urea treatment, six kinds of loss-control urea with the loss-control agent of 1 % -6 % could increase the rice yield in some degree, among which 1 % adding amount performed the best. The yield increasing rate was up to 12.22 %. The adding amounts of 1 % , 2 % and 6 % enables absorption of nitrogen, phosphorus, potassium by rice and accumulation in the rice seeds sufficiently to promote the yield and quality of rice. The adding amount of 3 % enhanced the accumulation of nitrogen, phosphorus and potassium in rice straw, increased the resistance and promoted the growth. [Conclusion] To sum up, the effect of urea with 1 % loss-control agent performed the best in rice production. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to understand chemical properties and available microelement characteristics of soil for growth of wild Bletilla striaes, explicit suitable soil environment of Bletilla.striaes cultivation and provide a reference for soil environment selection of Bletilla.striaes artificial cultivation. [Method] The microelement effective state and chemical properties of soil for growth of wild Bletilla.striata were investigated by field survey and the sufficient and lack level was analyzed by indoor analysis to discuss restriction factors affecting soil available microelement content. [Result] The pH and content of organic matter, total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, rapid available potassium, available Cu, available Zn, available Fe and available Mn in soil of Bletilla.striata cultivation are 7.65-7.99, 26.86-280.58 g/kg, 1.55-14.44 g/kg, 0.47-0.99 g/kg, 1.89-19.52 g/kg, 99-641 mg/kg, 2.40-18.75 mg/kg, 70-122 mg/kg, 0.45-1.70 mg/kg, 0.83-14.66 mg/kg, 11.80-119.85 mg/kg and 24.88-52.55 mg/kg respectively. [Conclusion] The suitable soil environment for Bletilla.striats growth is alkalescence and needs higher content of organic matter, total nitrogen, total phosphorus, available nitrogen, available phosphorus and rapid available potassium. The soil organic matter, N, P and K content has no obvious effect on Cu and Mn content in soil. The content of organic matter, total nitrogen, available nitrogen and available phosphorus in soil is positively related to Zn and Fe content very significantly.Selecting the soil with higher content of organic matter, total nitrogen, available nitrogen and available phosphorus can improve available Zn and Fe content in soil during Bletilla.striata artificial cultivation process, which is beneficial to growth and quality of Bletilla striata. [ABSTRACT FROM AUTHOR]

[Objective]This paper aimed to grasp the difference of soil nutrient content among die ancient lea gardens in Menghai county and provide a scientific basis for their soil nutrient management, which will help the county § tea production to achieve high-efficiency, high-quality and ecological goals. [Method] A total of 9 representative ancient lea gardens in Menghai county were selected for soil sampling, and the results were analyzed comprehensively. [Result] The pH value of 66.7% of the ancient tea gardens soil was 4.5 -5.5, and 33.3 % was lower than 4.5; the organic matter content of 22.2% of the ancient lea gardens was higher than 30 g/kg, and 77.8 % was between 10 g/kg and 30 g/kg; all the alkali-hydrolyzed nitrogen content exceeded 120 mg/kg; the available phosphorus content of 88.9 % of the ancient tea gardens was less than 3 mg/kg; the available potassium content of 66.7% of the ancient tea gardens was less than 50 mg/kg. [Conclusion] In the soil of the ancient lea gardens, the pH value of some tea plantations was lower than 4.5; the contents of organic matter and alkali-hydrolyzed nitrogen were relatively rich; the contents of available phosphorus and available potassium were relatively deficient. We should give full play to all kinds of organic fertilizer resources, increase the soil fertility of ancient lea gardens, use good soil testing and formula fertilization technology, improve the soil nutrient structure and pH value of ancient tea gardens, and ensure that there are reasonable and efficient soil nutrient banks in ancient lea gardens. [ABSTRACT FROM AUTHOR]

Schima superba is a dominant species in the lower subtropical evergreen broad-leaved forest community at Dinghushan. In order to understand the construction mechanism of lower subtropical evergreen broad-leaved forest community, we have established a 20 hm2 forest biodiversity monitoring plot at Dinghushan National Nature Reserve. The data presented in this paper are based on four field investigations of all S. superba individuals from 2005 to 2017. We further analyzed the distribution characteristics of its death rate according to diameter class and habitat type. The results were as follows:(1)The number of S. superba individuals was largely reduced from 2005 to 2017.(2)Mortality rate and growth rate of S. superba showed different patterns depending on diameter class. The relative growth rate of the individuals of 1-10 cm DBH was high and rapidly decreased, while the mortality rate increased and maintained at a high level. With the increase of DBH class, the relative growth rate of the individuals of 10-50 cm DBH rose and decelerated, and then decreased, while the mortality rate decreased. The mortality rate of those individuals above 50 cm DBH was large while the growth rate was little.(3)The mortality rate of the individuals in each habitat in 2010 was not apparently different. However, in 2015, the mortality rate of individuals in high-altitude habitats(high slopes, ridges, and valleys)was greater than those in low-altitude habitats(low slopes and valleys), while those in low-altitude habitats in 2017 were higher than those in the high-altitude habitats.(4)The mortality rate was significantly positively correlated with soil pH and negatively correlated with soil organic matter, total nitrogen, total phosphorus, available potassium, and available nitrogen content. [ABSTRACT FROM AUTHOR]

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.)

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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.)