One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and fro...One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and from PI to heading(HS)is expected to synchronize the double-peak N demand of rice.However,its effects on the yield and N use efficiency(NUE)of labor-intensive double-cropping rice were unknown.Two targeted CRU(CRU_(A)and CRU_(B))were compounded in five ratios(CRU_(A):CRU_(B)=10:0,7:3,5:5,3:7,and 0:10)to form five mixed fertilizers(BBFs):BBF1-5.A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake,yield,and ammonia volatilization(AV)loss from paddy fields of double-cropping rice.Conventional high-yield fertilization(CK,three split applications of urea)and zero-N treatments were established as controls.The N supply dropped significantly with the increased compound ratio of CRU_(B)during the period from TS to PI,but increased during the period from PI to HS.With the exception of the period from TS to PI in the late rice season,the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods.Excessive N supply(BBF1 and BBF2)in the late rice season during the period from TS to PI increased N loss by AV.The effect of BBF on grain yield increase varied widely between seasons,irrespective of year.Among the BBFs,the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage,resulting in the highest rice yield.While stabilizing the effective panicle number,the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS,resulting in the highest rice yield.The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha 1 and 45.3%,while those of late rice in BBF4 were 9.6 t ha 1 and 43.0%,respectively.The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK.The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0%and 76.8%lower,respectively,than those of CK.BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons,ensuring rice yield and NUE and reducing AV loss in paddy fields.展开更多
This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005...This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.展开更多
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has...Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture.展开更多
Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residu...Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residues in the soil due to their slow degradation. Limited information is available on the effects of substantial residual coatings on the soil bacterial community. By adding 0, 5, 10, 20, and 50 times quantities of residual coating from conventional application amount of resin and water-soluble coated CRFs, we studied the responses of soil properties and bacterial community composition to these two residual coatings in black soil. The results showed that the resin and water-soluble coatings did not essentially alter the properties of black soil or cause dramatic changes to bacterial diversity within the test concentration range. The residual resin and water-soluble coatings also did not distinctly alter the relative abundance of the top ten bacteria at phylum level. Heatmap results suggested that the treatments were basically clustered into two groups by concentration rather than types of coating material. Pearson correlation analysis showed that the Simpson's diversity index of the bacterial community was significantly correlated with microbial biomass carbon (MBC, r=0.394, P〈0.05), and the richness index abundance-based coverage estimator (ACE) of the bacterial community was significantly correlated with microbial biomass nitrogen (MBN, t=0.407, P〈0.05). Overall, results of this study suggested that substantial residual resin and water-soluble coatings with 0-50 times quantities of residual coating from conventional application amount of coated CRFs did not generate obviously negative impacts on the bacterial community in black soil.展开更多
This experiment explored the effects of single application of seven types of slow-and controlled-release fertilizers on rice yield and various population characteristics.Based on a study of the nitrogen(N)release char...This experiment explored the effects of single application of seven types of slow-and controlled-release fertilizers on rice yield and various population characteristics.Based on a study of the nitrogen(N)release characteristics of these fertilizers,pot experiments were conducted in 2018 and 2019 with split fertilization(CK,urea applied split equally at basal and panicle initiation stages,respectively)as control,which assessed the effects on SPAD value,yield and yield components,dynamic changes of rice tillers and dry matter accumulation.The results showed that the N release characteristics of different types of slow-and controlled-release fertilizers were significantly different.Polymer-coated urea(PCU)showed a controlledrelease mode and provided sustained release throughout the whole growth stages.Sulfur-coated urea(SCU)exhibited a slow-release mode,providing insufficient release at the middle and late stages.Urease inhibitor urea(AHA)and ureaformaldehyde(UF)yielded a rapid-release mode,with an explosive N release at the early stage and no release at the middle and late stages.These results showed that PCU delayed the peak seedling stage.Compared with CK,dry matter accumulation and SPAD showed no significant differences,and due to the continuous release of N throughout the growth stages,rice yield,spikelets per panicle,seed setting rate,and 1000-grain weight were all increased.Owing to the lack of N supply at the late stage and the low number of spikelets,SCU led to a reduction of rice yield,which is nevertheless not statistically significant.AHA and UF were susceptible to environmental factors and had varying effects on rice yield.The results of this experiment indicated that given a fixed amount of N applied in a pot,the stronger the N supply capacity and the longer the effective duration time of the fertilizer,the higher the dry matter accumulation at the late growth stage,and the higher the rice yield.展开更多
The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fer...The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fertilizer (CRNF), urea and no nitrogen fertilizer. CRNF showed obvious effects on delaying the senescence and prolonging photosynthetic function duration of rice leaves. Compared with urea, CRNF could significantly increase the chlorophyll content of functional leaves in both early and late rice varieties, and this difference between the treatments became larger as rice growth progressed; CRNF increased the activities of active oxygen scavenging enzymes super oxide dismutase (SOD) and peroxidase (POD), and decreased the accumulation amount of malondialdehyde (MDA) in functional leaves during leaf aging; Photosynthetic rate of functional leaves in CRNF treatment was significantly higher than that in urea treatment. The result also indicated that CRNF could effectively regulate the contents of indole-3-acetic acid (IAA) and abscisic acid (ABA) in functional leaves; IAA content was higher and ABA content was lower in CRNF treatment than those in urea treatment. Therefore, application of CRNF could increase the rice yield significantly due to these physiological changes in the functional leaves.展开更多
Encapsulation of water-soluble nitrogen fertilizers by membranes can be used to control the release of nutrients to maximize the fertilization ef fect and reduce environmental pollution.In this research,we formulated ...Encapsulation of water-soluble nitrogen fertilizers by membranes can be used to control the release of nutrients to maximize the fertilization ef fect and reduce environmental pollution.In this research,we formulated a new double-coated controlled-release fertilizer(CRF)by using food-grade microcrystalline wax(MW)and marine polysaccharide derivatives(calcium alginate and chitosan-glutaraldehyde copolymer).The pellets of water-soluble nitrogen fertilizer were coated with the marine polysaccharide derivatives and MW.A convenient and eco-friendly method was used to prepare the CRF.Scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FTIR)were used to characterize the morphology and composition of the products.The nitrogen-release properties were determined in water using UV-Vis spectrophotometry.The controlled-release properties of the fertilizer were improved dramatically after coating with MW and the marine polysaccharide derivatives.The results show that the double-coated CRFs can release nitrogen in a controlled manner,have excellent controlled-release features,and meet the European Standard for CRFs.展开更多
Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphat...Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; andC-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, andtheir application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zeamays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Underco-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for bothdent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were highin experiment 1, but were very low in experiment 2, because the environmental conditions were different in the twoexperiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrientconcentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease inexperiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between co-situs and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot androot weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially atthe fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situsapplication and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation wasreversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cmdepth).展开更多
Controlled-release urea(CRU)is widely reported to supply crop nitrogen(N)demand with one basal application,thus effectively replacing split applications of urea without diminishing grain yield and N use efficiency(NUE...Controlled-release urea(CRU)is widely reported to supply crop nitrogen(N)demand with one basal application,thus effectively replacing split applications of urea without diminishing grain yield and N use efficiency(NUE).However,its use for replacement for high-yield split applications of urea(CK)for rice is untested.In addition,the degree to which greenhouse gas(GHG)emissions in rice systems are affected when CRU is substituted for CK remains unclear.During 2017 and 2018,we sampled plant growth and gas emissions in a rice paddy field treated with three CRU types(sulfur-coated urea[SCU],polymer-coated urea[PCU],and bulk blended CRU[BBU])applied via two methods(surface broadcasting on the soil and subsurface banding at 5 cm depth),with CK as a control.The three CRUs led to different soil NH_(4)^(+)-N dynamics,and the N supply pattern under BBU was more beneficial for rice seedling establishment than under SCU and PCU,resulting in grain yield and NUE comparable to those under CK.CRU type showed no significant effect on either CH_(4) emissions or N_(2)O emissions,and broadcast CRUs exhibited significantly higher total GHG emissions than CK.However,banded CRUs significantly reduced the total GHG emissions in comparison with broadcast CRUs,by 9.2%averaged across the two years.Reduced CH_(4) emissions,particularly during the period prior to the middle drainage,contributed largely to the GHG difference.With comparably high grain yield and low total GHG emissions,banded BBU showed a low yield-scaled GHG(GHG emissions divided by grain yield)comparable to that under CK in both years.Overall,our study suggested that N management synchronized with rice demand and contributing to a high NUE tended to minimize yield-scaled GHG.Broadcast CRU can hardly substitute for CK in terms of either grain yield or GHG emissions,but banded BBU is a promising N management strategy for sustaining rice production while minimizing environmental impacts.展开更多
Heavy use of conventional fertilizers can lead to negative environmental concerns.Controlled-release fertilizers(CRFs)can effectively reduce the amounts of fertilizers used,improve the availability of fer-tilizers,and...Heavy use of conventional fertilizers can lead to negative environmental concerns.Controlled-release fertilizers(CRFs)can effectively reduce the amounts of fertilizers used,improve the availability of fer-tilizers,and which is conducive to the protection of the ecological environment and sustainable devel-opment of agriculture.Therefore,it is imperative to develop and use CRFs as an alternative to traditional fertilizers.This review aims to present the classification,raw material composition,benefits,release process,release mode,and manufacturing methods of fertilizers coated with organic-inorganic com-posite membranes(OICMs)in order to provide an overall update and summarize CRFs encapsulated by OICMs and provide an insight for future trends in the field of fertilizers.It is expected that utilizing CRFs encapsulated by OICMs and their characteristics for agricultural applications can provide innovative ideas and suggestions for developing novel CRFs suitable for modern and sustainable agriculture.展开更多
Nitrogen(N) fertilizers in agriculture suffer losses by volatilization of N to the air, surface runoff and leaching into the soil, resulting in low N use efficiency(NUE)( 50%) and raising severe environmental pollutio...Nitrogen(N) fertilizers in agriculture suffer losses by volatilization of N to the air, surface runoff and leaching into the soil, resulting in low N use efficiency(NUE)( 50%) and raising severe environmental pollutions. Controlledrelease nitrogen fertilizers(CRNFs) can control the release of N nutrients to NUE in crop production. Different methods were used to develop new CRNFs.However, different CRNF technologies are still underdeveloped due to inadequate controlling on N releasing time and/or unsustainable diffusion. The study on the influences of CRNF processing parameters on microbial conditions are lacking when the CRNFs composed of various bio-ingredients such as biochar, composts, and biowaste. The complexity of processing methods, material biodegradability, and other physical properties make current CRNFs of questionable value in agricultural production. This research aims to develop a novel biochar-compost-based controlled-release urea fertilizer(BCRUF) to preserve microbial properties carried by the compost. The BCRUF was synthesized by pelletizing the 50:50(dry, wt/wt) mixture of biochar and compost. BCRUF was loaded with urea and then spray-coated with polylactic acid(PLA). The releasing time of two types of BCRUFs, coated and uncoated with PLA, for 80% of N release in water was up to 6 h at three different temperatures(4, 23, and 40 °C), compared to conventional urea fertilizer and commercial environmentally smart N(ESN) fertilizer. The releasing time of coated BCRUF for 80% N release in soil was up to 192 h(8 days). Fourier-transform infrared spectroscopy(FTIR) analysis revealed that no new functional groups were found in the release solution, indicating no new chemical hazards generated. The differential scanning calorimetry(DSC)tests also verified that its thermal stability could be up to 160 °C. The microbe populations in the BCRUF pellets were reduced after the pelleting and drying processes in BCRUF fabrication, but a few bacteria can endure in the air-drying process. BCRUF pellets soaked in water for 4 days retained some bacteria. The BCRUF showed very promising characteristics to improve NUE and sustainability in agricultural production.展开更多
Two field experiments were conducted during two successive winter seasons of 2008/2009 and 2009/2010 to investigate the potentialities of mixing Egyptian clover with ryegrass under bio, organic and mineral fertilizati...Two field experiments were conducted during two successive winter seasons of 2008/2009 and 2009/2010 to investigate the potentialities of mixing Egyptian clover with ryegrass under bio, organic and mineral fertilization treatments and their combination to increase forage yield and quality grown under sandy soil conditions. The experiment included the combination of five mixing ratios (Egyptian clover alone, ryegrass alone, 75% Egyptian clover: 25% ryegrass, 50% Egyptian clover: 50% ryegrass and 25% Egyptian clover: 75% ryegrass) and eight fertilizer sources, which include control, organic fertilization, bio fertilization, chemical fertilizer, organic + bio fertilizer, organic + chemical fertilizer, bio + chemical fertilizer and combination of organic and chemical and bio fertilizers. The obtained results indicate the superiority of 75% E. clover: 25% ryegrass mixture fertilizedby Bio + O + N in fresh and dry forage production. On the other hand, it reported the lowest dry weight of weeds g/m2. Chemical analysis of forage plants showed that the mixture of ?75% E. clover: 25% ryegrass surpassed that of other treatments yield for crude protein, ether extract and ash. The results also revealed that the highest record of DCP, crude fiber and TDNY was obtained by forage mixture of 75% E. clover: 25% ryegrass fertilized with Bio + O + N. Such higher yield of these characters hassecured a balanced ratio which is really needed for ruminants ration.展开更多
Objective] The aim was to explain the accumulation characteristic of mineral elements in alpine grassland plants and the effect of supplementary supply on the nutrient changes of mineral elements. [Method] Potted Poa ...Objective] The aim was to explain the accumulation characteristic of mineral elements in alpine grassland plants and the effect of supplementary supply on the nutrient changes of mineral elements. [Method] Potted Poa crymophila cv. Qinghai plants were regularly applied with liquid mineral mixed fertilizers, and samples were collected for analysis and detection. [Result] After the regular spraying of liquid mineral mixed fertilizers, the mineral elements in potted P. crymophila and its soil reduced ( P 〈0.05), but the accumulation of corresponding mineral elements of P. crymophila in the control group was increased due to the "Starvation Effect", which was one of the endogenetic forces driving the increase in the accumulation of mineral elements. [Conclusion] This study is of great significance for the study of the accumulation of mineral elements in degraded grassland plants and its dynamic mechanism, as well as testing the hypothesis of the Starvation Effect of mineral elements. In addition, it also provides scientific bases and technical support for the restoration and remediation of degraded grassland and the development of ecological livestock husbandry.展开更多
Mixed model analysis procedure was used to analyze the effect of fertilizer application on the Fresh Fruit Bunch (FFB) yield of oil palm. This was with a view to achieve the most appropriate and a robust model for ana...Mixed model analysis procedure was used to analyze the effect of fertilizer application on the Fresh Fruit Bunch (FFB) yield of oil palm. This was with a view to achieve the most appropriate and a robust model for analyzing yield response for fertilizer application in oil palm. In this study, a mixed model analysis procedure was used to analyze yield data obtained from a fertilizer trial conducted between 1997 and 2005. In mixed effect model, replicates and years were used as block. In contrast the fixed effect ANOVA model usually lumped up replicates and years as a random error. In the model replicates were used as block with no block interaction, replicates as block with allowance for block-fertilizer interaction, years as block with allowance for block-fertilizer interaction, and years and replicates as block with allowance for year fertilizer and replicate-fertilizer interaction. Mixed model theory was also used to provide the explicit description of the design matrices in the models. Also, hypotheses relevant to each model were formulated and used to test for specific effects in the models such as, fixed part, random part and interacting parts using appropriate error terms as determined by the derived Expected Mean Squares (EMS). The results revealed that at 5% significant level (p展开更多
Controlled-release urea(CRU)releases nitrogen(N)at the same pace that rice takes it up,which can effectively improve N use efficiency,increase rice yield and improve rice quality.However,few studies have described the...Controlled-release urea(CRU)releases nitrogen(N)at the same pace that rice takes it up,which can effectively improve N use efficiency,increase rice yield and improve rice quality.However,few studies have described the effects of CRU application on the photosynthetic rate and endogenous enzyme activities of rice.Accordingly,a twoyear field trial was conducted with a total of seven treatments:CK,no N fertilizer;BBF,regular blended fertilizer;RBBF,20%N-reduced regular blended fertilizer;CRF1,70%CRU+30%regular urea one-time base application;CRF2,60%CRU+40%regular urea one-time base application;RCRF1,CRF1 treatment with 20%N reduction;and RCRF2,CRF2 treatment with 20%N reduction.Each treatment was conducted in triplicate.The results showed that the N recovery efficiency(NRE)of the controlled-release bulk blending fertilizer(CRBBF)treatments was significantly greater over the two years.There were significant yield increases of 4.1–5.9%under the CRF1treatment and 5.6–7.6%under the CRF2 treatment compared to the BBF treatment,but the differences between the reduced-N treatments RBBF and RCRF2 were not significant.Photosynthetic rates under the CRF1 and CRF2treatments were significantly higher than under the other treatments,and they had significantly greater RuBPCase,RuBisCO,glutamate synthase(GOGAT)and glutamine synthetase(GS)enzyme activities.Additionally,the soil NH_(4)^(+)-N and NO_(3)^(–)-N contents under the CRBBF treatments were significantly higher at the late growth stage of rice,which was more in-line with the fertilizer requirements of rice throughout the reproductive period.CRBBF also led to some improvement in rice quality.Compared with the BBF and RBBF treatments,the protein contents under the CRBBF treatments were reduced but the milling,appearance,eating and cooking qualities of the rice were improved.These results showed that the application of CRBBF can improve the NRE,photosynthetic rate and endogenous enzyme activities of rice,ensuring sufficient N nutrition and photosynthetic material production during rice growth and thereby achieving improved rice yield and quality.展开更多
基金provided by the National Key Research and Development Program of China(2018YFD0300904)Anhui Natural Science Foundation(2008085QC119)Key Fund Project of Anhui Department of Education(KJ2019A0176).
文摘One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers(CRUs)with targeted N supply during the periods from transplantation(TS)to panicle initiation(PI)and from PI to heading(HS)is expected to synchronize the double-peak N demand of rice.However,its effects on the yield and N use efficiency(NUE)of labor-intensive double-cropping rice were unknown.Two targeted CRU(CRU_(A)and CRU_(B))were compounded in five ratios(CRU_(A):CRU_(B)=10:0,7:3,5:5,3:7,and 0:10)to form five mixed fertilizers(BBFs):BBF1-5.A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake,yield,and ammonia volatilization(AV)loss from paddy fields of double-cropping rice.Conventional high-yield fertilization(CK,three split applications of urea)and zero-N treatments were established as controls.The N supply dropped significantly with the increased compound ratio of CRU_(B)during the period from TS to PI,but increased during the period from PI to HS.With the exception of the period from TS to PI in the late rice season,the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods.Excessive N supply(BBF1 and BBF2)in the late rice season during the period from TS to PI increased N loss by AV.The effect of BBF on grain yield increase varied widely between seasons,irrespective of year.Among the BBFs,the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage,resulting in the highest rice yield.While stabilizing the effective panicle number,the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS,resulting in the highest rice yield.The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha 1 and 45.3%,while those of late rice in BBF4 were 9.6 t ha 1 and 43.0%,respectively.The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK.The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0%and 76.8%lower,respectively,than those of CK.BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons,ensuring rice yield and NUE and reducing AV loss in paddy fields.
文摘This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice (Oryza sativa L.). Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance (CRF1) and polymer materials (CRF3) increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer (RSF1). Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.
文摘Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture.
基金supported by the International Scientific and Technological Cooperation Projects of China (2015DFA20790)the National Natural Science Foundation of China (21577172,41501322)the National Basic Research Program (973 program) of China (2013CB127406)
文摘Coated controlled-release fertilizers (CRFs) have been widely applied in agriculture due to their increased efficiency. However, the widespread and a lot of coated CRFs application may leave undesired coating residues in the soil due to their slow degradation. Limited information is available on the effects of substantial residual coatings on the soil bacterial community. By adding 0, 5, 10, 20, and 50 times quantities of residual coating from conventional application amount of resin and water-soluble coated CRFs, we studied the responses of soil properties and bacterial community composition to these two residual coatings in black soil. The results showed that the resin and water-soluble coatings did not essentially alter the properties of black soil or cause dramatic changes to bacterial diversity within the test concentration range. The residual resin and water-soluble coatings also did not distinctly alter the relative abundance of the top ten bacteria at phylum level. Heatmap results suggested that the treatments were basically clustered into two groups by concentration rather than types of coating material. Pearson correlation analysis showed that the Simpson's diversity index of the bacterial community was significantly correlated with microbial biomass carbon (MBC, r=0.394, P〈0.05), and the richness index abundance-based coverage estimator (ACE) of the bacterial community was significantly correlated with microbial biomass nitrogen (MBN, t=0.407, P〈0.05). Overall, results of this study suggested that substantial residual resin and water-soluble coatings with 0-50 times quantities of residual coating from conventional application amount of coated CRFs did not generate obviously negative impacts on the bacterial community in black soil.
基金the National Key Research and Development Program of China(22017YFD0301203,2018YFD0300803)the Jiangsu Key Research and Development Program,China(BE2017369)the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(18)1002)。
文摘This experiment explored the effects of single application of seven types of slow-and controlled-release fertilizers on rice yield and various population characteristics.Based on a study of the nitrogen(N)release characteristics of these fertilizers,pot experiments were conducted in 2018 and 2019 with split fertilization(CK,urea applied split equally at basal and panicle initiation stages,respectively)as control,which assessed the effects on SPAD value,yield and yield components,dynamic changes of rice tillers and dry matter accumulation.The results showed that the N release characteristics of different types of slow-and controlled-release fertilizers were significantly different.Polymer-coated urea(PCU)showed a controlledrelease mode and provided sustained release throughout the whole growth stages.Sulfur-coated urea(SCU)exhibited a slow-release mode,providing insufficient release at the middle and late stages.Urease inhibitor urea(AHA)and ureaformaldehyde(UF)yielded a rapid-release mode,with an explosive N release at the early stage and no release at the middle and late stages.These results showed that PCU delayed the peak seedling stage.Compared with CK,dry matter accumulation and SPAD showed no significant differences,and due to the continuous release of N throughout the growth stages,rice yield,spikelets per panicle,seed setting rate,and 1000-grain weight were all increased.Owing to the lack of N supply at the late stage and the low number of spikelets,SCU led to a reduction of rice yield,which is nevertheless not statistically significant.AHA and UF were susceptible to environmental factors and had varying effects on rice yield.The results of this experiment indicated that given a fixed amount of N applied in a pot,the stronger the N supply capacity and the longer the effective duration time of the fertilizer,the higher the dry matter accumulation at the late growth stage,and the higher the rice yield.
基金National Natural Science Foundation of China(30270770)Foundation for Achievement Transfer(02EFN214301156) Key Subject Foundation of Hunan Academy of Agricultural Sciences(03-05).
文摘The physiological mechanism of photosynthetic function and senescence of rice leaves was studied by using early rice variety Baliangyou 100 and late rice variety Weiyou 46, treated with controlled-release nitrogen fertilizer (CRNF), urea and no nitrogen fertilizer. CRNF showed obvious effects on delaying the senescence and prolonging photosynthetic function duration of rice leaves. Compared with urea, CRNF could significantly increase the chlorophyll content of functional leaves in both early and late rice varieties, and this difference between the treatments became larger as rice growth progressed; CRNF increased the activities of active oxygen scavenging enzymes super oxide dismutase (SOD) and peroxidase (POD), and decreased the accumulation amount of malondialdehyde (MDA) in functional leaves during leaf aging; Photosynthetic rate of functional leaves in CRNF treatment was significantly higher than that in urea treatment. The result also indicated that CRNF could effectively regulate the contents of indole-3-acetic acid (IAA) and abscisic acid (ABA) in functional leaves; IAA content was higher and ABA content was lower in CRNF treatment than those in urea treatment. Therefore, application of CRNF could increase the rice yield significantly due to these physiological changes in the functional leaves.
基金Supported by the National Natural Science Foundation of China(No.41306071)the CAS STS Program(No.KFJ-SW-STS-143)+1 种基金the NSFC-Shandong Union Project(No.U1406402-5)the Public Science and Technology Research Funds Projects of Ocean(Nos.201405038-2,201305016-2)
文摘Encapsulation of water-soluble nitrogen fertilizers by membranes can be used to control the release of nutrients to maximize the fertilization ef fect and reduce environmental pollution.In this research,we formulated a new double-coated controlled-release fertilizer(CRF)by using food-grade microcrystalline wax(MW)and marine polysaccharide derivatives(calcium alginate and chitosan-glutaraldehyde copolymer).The pellets of water-soluble nitrogen fertilizer were coated with the marine polysaccharide derivatives and MW.A convenient and eco-friendly method was used to prepare the CRF.Scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FTIR)were used to characterize the morphology and composition of the products.The nitrogen-release properties were determined in water using UV-Vis spectrophotometry.The controlled-release properties of the fertilizer were improved dramatically after coating with MW and the marine polysaccharide derivatives.The results show that the double-coated CRFs can release nitrogen in a controlled manner,have excellent controlled-release features,and meet the European Standard for CRFs.
基金partly supported by the National Natural Science Foundation of China(NFSC)(30230230 and 30070429)
文摘Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; andC-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, andtheir application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zeamays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Underco-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for bothdent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were highin experiment 1, but were very low in experiment 2, because the environmental conditions were different in the twoexperiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrientconcentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease inexperiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between co-situs and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot androot weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially atthe fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situsapplication and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation wasreversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cmdepth).
基金supported by the Natural Science Foundation of Jiangsu Province(BK20200539)Postdoctoral Research Foundation of China(2019M661863)Jiangsu Provincial Key Research and Development Program(BE2019377,BE2019343)。
文摘Controlled-release urea(CRU)is widely reported to supply crop nitrogen(N)demand with one basal application,thus effectively replacing split applications of urea without diminishing grain yield and N use efficiency(NUE).However,its use for replacement for high-yield split applications of urea(CK)for rice is untested.In addition,the degree to which greenhouse gas(GHG)emissions in rice systems are affected when CRU is substituted for CK remains unclear.During 2017 and 2018,we sampled plant growth and gas emissions in a rice paddy field treated with three CRU types(sulfur-coated urea[SCU],polymer-coated urea[PCU],and bulk blended CRU[BBU])applied via two methods(surface broadcasting on the soil and subsurface banding at 5 cm depth),with CK as a control.The three CRUs led to different soil NH_(4)^(+)-N dynamics,and the N supply pattern under BBU was more beneficial for rice seedling establishment than under SCU and PCU,resulting in grain yield and NUE comparable to those under CK.CRU type showed no significant effect on either CH_(4) emissions or N_(2)O emissions,and broadcast CRUs exhibited significantly higher total GHG emissions than CK.However,banded CRUs significantly reduced the total GHG emissions in comparison with broadcast CRUs,by 9.2%averaged across the two years.Reduced CH_(4) emissions,particularly during the period prior to the middle drainage,contributed largely to the GHG difference.With comparably high grain yield and low total GHG emissions,banded BBU showed a low yield-scaled GHG(GHG emissions divided by grain yield)comparable to that under CK in both years.Overall,our study suggested that N management synchronized with rice demand and contributing to a high NUE tended to minimize yield-scaled GHG.Broadcast CRU can hardly substitute for CK in terms of either grain yield or GHG emissions,but banded BBU is a promising N management strategy for sustaining rice production while minimizing environmental impacts.
基金funded by the Key Project of the Science and Technology Department of Jilin Province,China(grant No.20220203079SF)Independent Research Project in 2020 of State Key Laboratory of Supramolecular Structure and Materials(grant No.CXKT202008).
文摘Heavy use of conventional fertilizers can lead to negative environmental concerns.Controlled-release fertilizers(CRFs)can effectively reduce the amounts of fertilizers used,improve the availability of fer-tilizers,and which is conducive to the protection of the ecological environment and sustainable devel-opment of agriculture.Therefore,it is imperative to develop and use CRFs as an alternative to traditional fertilizers.This review aims to present the classification,raw material composition,benefits,release process,release mode,and manufacturing methods of fertilizers coated with organic-inorganic com-posite membranes(OICMs)in order to provide an overall update and summarize CRFs encapsulated by OICMs and provide an insight for future trends in the field of fertilizers.It is expected that utilizing CRFs encapsulated by OICMs and their characteristics for agricultural applications can provide innovative ideas and suggestions for developing novel CRFs suitable for modern and sustainable agriculture.
基金funding supports from the South Dakota Governor’s Office of Economic Development (POC2020-04)the USDA NIFA through the North Central Regional Sun Grant Center, and Hatch Projects (3AR652, 3AR689, and 3AH658) of the South Dakota Agricultural Experiment Station。
文摘Nitrogen(N) fertilizers in agriculture suffer losses by volatilization of N to the air, surface runoff and leaching into the soil, resulting in low N use efficiency(NUE)( 50%) and raising severe environmental pollutions. Controlledrelease nitrogen fertilizers(CRNFs) can control the release of N nutrients to NUE in crop production. Different methods were used to develop new CRNFs.However, different CRNF technologies are still underdeveloped due to inadequate controlling on N releasing time and/or unsustainable diffusion. The study on the influences of CRNF processing parameters on microbial conditions are lacking when the CRNFs composed of various bio-ingredients such as biochar, composts, and biowaste. The complexity of processing methods, material biodegradability, and other physical properties make current CRNFs of questionable value in agricultural production. This research aims to develop a novel biochar-compost-based controlled-release urea fertilizer(BCRUF) to preserve microbial properties carried by the compost. The BCRUF was synthesized by pelletizing the 50:50(dry, wt/wt) mixture of biochar and compost. BCRUF was loaded with urea and then spray-coated with polylactic acid(PLA). The releasing time of two types of BCRUFs, coated and uncoated with PLA, for 80% of N release in water was up to 6 h at three different temperatures(4, 23, and 40 °C), compared to conventional urea fertilizer and commercial environmentally smart N(ESN) fertilizer. The releasing time of coated BCRUF for 80% N release in soil was up to 192 h(8 days). Fourier-transform infrared spectroscopy(FTIR) analysis revealed that no new functional groups were found in the release solution, indicating no new chemical hazards generated. The differential scanning calorimetry(DSC)tests also verified that its thermal stability could be up to 160 °C. The microbe populations in the BCRUF pellets were reduced after the pelleting and drying processes in BCRUF fabrication, but a few bacteria can endure in the air-drying process. BCRUF pellets soaked in water for 4 days retained some bacteria. The BCRUF showed very promising characteristics to improve NUE and sustainability in agricultural production.
文摘Two field experiments were conducted during two successive winter seasons of 2008/2009 and 2009/2010 to investigate the potentialities of mixing Egyptian clover with ryegrass under bio, organic and mineral fertilization treatments and their combination to increase forage yield and quality grown under sandy soil conditions. The experiment included the combination of five mixing ratios (Egyptian clover alone, ryegrass alone, 75% Egyptian clover: 25% ryegrass, 50% Egyptian clover: 50% ryegrass and 25% Egyptian clover: 75% ryegrass) and eight fertilizer sources, which include control, organic fertilization, bio fertilization, chemical fertilizer, organic + bio fertilizer, organic + chemical fertilizer, bio + chemical fertilizer and combination of organic and chemical and bio fertilizers. The obtained results indicate the superiority of 75% E. clover: 25% ryegrass mixture fertilizedby Bio + O + N in fresh and dry forage production. On the other hand, it reported the lowest dry weight of weeds g/m2. Chemical analysis of forage plants showed that the mixture of ?75% E. clover: 25% ryegrass surpassed that of other treatments yield for crude protein, ether extract and ash. The results also revealed that the highest record of DCP, crude fiber and TDNY was obtained by forage mixture of 75% E. clover: 25% ryegrass fertilized with Bio + O + N. Such higher yield of these characters hassecured a balanced ratio which is really needed for ruminants ration.
基金Supported by the General Program of Natural Science Foundation of Qinghai Province(2016-ZJ-906)
文摘Objective] The aim was to explain the accumulation characteristic of mineral elements in alpine grassland plants and the effect of supplementary supply on the nutrient changes of mineral elements. [Method] Potted Poa crymophila cv. Qinghai plants were regularly applied with liquid mineral mixed fertilizers, and samples were collected for analysis and detection. [Result] After the regular spraying of liquid mineral mixed fertilizers, the mineral elements in potted P. crymophila and its soil reduced ( P 〈0.05), but the accumulation of corresponding mineral elements of P. crymophila in the control group was increased due to the "Starvation Effect", which was one of the endogenetic forces driving the increase in the accumulation of mineral elements. [Conclusion] This study is of great significance for the study of the accumulation of mineral elements in degraded grassland plants and its dynamic mechanism, as well as testing the hypothesis of the Starvation Effect of mineral elements. In addition, it also provides scientific bases and technical support for the restoration and remediation of degraded grassland and the development of ecological livestock husbandry.
文摘Mixed model analysis procedure was used to analyze the effect of fertilizer application on the Fresh Fruit Bunch (FFB) yield of oil palm. This was with a view to achieve the most appropriate and a robust model for analyzing yield response for fertilizer application in oil palm. In this study, a mixed model analysis procedure was used to analyze yield data obtained from a fertilizer trial conducted between 1997 and 2005. In mixed effect model, replicates and years were used as block. In contrast the fixed effect ANOVA model usually lumped up replicates and years as a random error. In the model replicates were used as block with no block interaction, replicates as block with allowance for block-fertilizer interaction, years as block with allowance for block-fertilizer interaction, and years and replicates as block with allowance for year fertilizer and replicate-fertilizer interaction. Mixed model theory was also used to provide the explicit description of the design matrices in the models. Also, hypotheses relevant to each model were formulated and used to test for specific effects in the models such as, fixed part, random part and interacting parts using appropriate error terms as determined by the derived Expected Mean Squares (EMS). The results revealed that at 5% significant level (p
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20220563)the Key R&D Program of Jiangsu Province,China(BE2022338)the Colleges and Universities in Jiangsu Province Natural Science Foundation of China(19KJB210014)。
文摘Controlled-release urea(CRU)releases nitrogen(N)at the same pace that rice takes it up,which can effectively improve N use efficiency,increase rice yield and improve rice quality.However,few studies have described the effects of CRU application on the photosynthetic rate and endogenous enzyme activities of rice.Accordingly,a twoyear field trial was conducted with a total of seven treatments:CK,no N fertilizer;BBF,regular blended fertilizer;RBBF,20%N-reduced regular blended fertilizer;CRF1,70%CRU+30%regular urea one-time base application;CRF2,60%CRU+40%regular urea one-time base application;RCRF1,CRF1 treatment with 20%N reduction;and RCRF2,CRF2 treatment with 20%N reduction.Each treatment was conducted in triplicate.The results showed that the N recovery efficiency(NRE)of the controlled-release bulk blending fertilizer(CRBBF)treatments was significantly greater over the two years.There were significant yield increases of 4.1–5.9%under the CRF1treatment and 5.6–7.6%under the CRF2 treatment compared to the BBF treatment,but the differences between the reduced-N treatments RBBF and RCRF2 were not significant.Photosynthetic rates under the CRF1 and CRF2treatments were significantly higher than under the other treatments,and they had significantly greater RuBPCase,RuBisCO,glutamate synthase(GOGAT)and glutamine synthetase(GS)enzyme activities.Additionally,the soil NH_(4)^(+)-N and NO_(3)^(–)-N contents under the CRBBF treatments were significantly higher at the late growth stage of rice,which was more in-line with the fertilizer requirements of rice throughout the reproductive period.CRBBF also led to some improvement in rice quality.Compared with the BBF and RBBF treatments,the protein contents under the CRBBF treatments were reduced but the milling,appearance,eating and cooking qualities of the rice were improved.These results showed that the application of CRBBF can improve the NRE,photosynthetic rate and endogenous enzyme activities of rice,ensuring sufficient N nutrition and photosynthetic material production during rice growth and thereby achieving improved rice yield and quality.