Effect of Slow and Controlled Release Fertilizers on the Yield and Nutrient Use Efficiency of Hot Pepper in Qiu-bei

[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers（SCRF）on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper（Capsicum frutescens L.）as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection.

Effects of slow or controlled release fertilizer types and fertilization modes on yield and quality of rice

There is limited information about the influence of slow or controlled release fertilizer（S/CRF） on rice yield and quality. In this study, japonica rice cultivar Nanjing 9108 was used to study the effects of three different S/CRFs（polymer-coated urea（PCU）, sulfur-coated urea（SCU）, and urea formaldehyde（UF）） and two fertilization modes（both S/CRF and common urea（CU） as basal fertilizer, S/CRF as basal and CU as tillering fertilizer） on rice yield and quality. CU only was applied separately as control（CK）. Results showed that, rice grain yield, chalky kernel rate, chalky area, overall chalkiness, and the content of gliadin, glutenin, and protein, all showed the trends of UF〉PCU〉SCU within the same fertilization mode, and showed the trends of S/CRF as basal and CU as tillering fertilizer〉both S/CRF and CU as basal fertilizer within the same type of S/CRF. In contrast, the contents of amylose, amylopectin, and starch, as well as taste value, and peak and hot viscosity showed trends of SCU〉PCU〉UF, and the trends of both S/CRF and CU as basal fertilizer〉S/CRF as basal and CU as tillering fertilizer. Among S/CRF treatments and fertilization modes, taste values of cooked rice were positively correlated with amylose, amylopectin, and starch contents, as well as gel consistency, peak viscosity, hot viscosity, and cool viscosity, while negatively correlated with globulin, gliadin, glutenin, and protein contents. The types of S/CRF and fertilization modes are important for improving rice yield and quality. Compared to CK, higher yield and similar quality of rice was achieved with UF as basal and CU as tillering fertilizer, and similar yield with improved appearance and eating and cooking quality of rice was achieved with either both UF and CU as basal fertilizer, or PCU as basal and CU as tillering fertilizer.

Release Characteristics of Different N Forms in an Uncoated Slow/Controlled Release Compound Fertilizer

This study examined the release characteristics of different N forms in an uncoated slow/controlled-release compound fertilizer （UCRF） and the N uptake and N-use efficiency by rice plants. Water dissolution, soil leaching, and pot experiments were employed. The dynamics of N release from the UCRF could be quantitatively described by three equations： the first-order kinetics equation [N1=N0 （1-e^-kt）], Elovich equation （N1=a ＋ blnt）, and parabola equation （N1=a ＋ bt^0.5）, with the best fitting by the first-order kinetics equation for different N （r= 0.9569^＊＊-0.9999^＊＊）. The release potentials （No values estimated by the first-order kinetics equation） of different N in the UCRF decreased in the order of total N 〉 DON 〉 urea-N 〉 NH4^＋-N 〉 NO3^-N in water, and total N 〉 NH4^＋-N 〉 DON 〉 urea-N 〉 NO3^--N in soil, respectively, being in accordance with cumulative amounts of N release. The constants of N release rate （k values and b values） for different N forms were in decreasing order of total N 〉 DON 〉 NH4^＋-N 〉 NO3^--N in water, whereas the k values were urea- N 〉DON 〉 NH4^＋-N 〉 total N 〉 NO3^--N, and the b values were total N 〉 NH4^＋-N 〉 DON 〉 NO3^--N 〉 urea-N in soil. Compared with a common compound fertilizer, the N-use efficiency, N-agronomy efficiency, and N-physiological efficiency of the UCRF were increased by 11.4%, 8.32 kg kg^-1, and 5.17 kg kg^-1, respectively. The ratios of different N to total N in the UCRF showed significant correlation with N uptake by rice plants. The findings showed that the first-order kinetics equation [Nt=N0 （l-e^kt）] could be used to describe the release characteristics of different N forms in the fertilizer. The UCRF containing different N forms was more effective in facilitating N uptake by rice compared with the common compound fertilizer containing single urea-N form.

Synthesis and Performance of Polyurethane Coated Urea as Slow/controlled Release Fertilizer

Polyurethane coated urea slow/controlled release fertilizer was prepared based on urea granules, isocyanate, polyols and paraffin. Isocyanate reacted with polyols to synthesize the polyurethane skin layer on urea granules surface. Paraffin serves as a lubricant during syntheses of polyurethane skin layers. The structure and nutrient release characteristics of the polyurethane skin layers were investigated by FTIR, SEM and TG. Urea nitrogen slow-release behavior of the polyurethane coated urea was tested. The experimental results indicated that compact and dense polyurethane skin layers with a thickness of 10-15 lam were formed on urea surface, the urea nitrogen slow-release time can reach 40-50 days. Paraffin proves to play a key role in inhibiting water to penetrate into urea, but excessive addition would decrease the polyurethane crosslinking density.

Use of Controlled Release Fertilizer for Increasing N Efficiency of Direct Seeding Rice

Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilizers) with the conventional urea. Six treatments including CK (no N fertilizer), conventional urea and different types of LP fertilizers at different rates were designed for two succeeding crops of early and late rice. A blend of different types of LP fertilizers as a single preplant "co-situs" application released N in a rate and amount synchronizing with uptake pattern of direct seeding rice. A single preplant application of the LP fertilizers could meet the N requirement of rice for the whole growth period without need of topdressing. Using LP fertilizer blends, equivalent grain yields could be maintained even if the N fertilization rates were reduced by 25%～50% compared with the conventional urea. Agronomic efficiency of the LP fertilizers was 13.6%～ 86.4% higher than that of the conventional urea in early rice and 100%～164.1% in late rice, depending on the amounts of the LP fertilizers applied. N fertilizer recovery rate increased from 27.4% for the conventional application of urea to 41.7%～54.l% for the single preplant "co-situs" application of the LP fertilizers. Use of the LP fertilizers was promising if the increase in production costs due to the high LP fertilizer prices could be compensated by increase in yield and N efficiency, reduction in labor costs and improvement in environment.

Effects of Application of Controlled Release Nitrogen Fertilizer on N_2O Emission in Slope Cultivated Land with Purple Soil

In order to study effects of application of contmllE=d release fertilizer on ni- trous oxide （N2O） emission in slope cultivated land with purple soil, four treatments including the control group （CK）, urea （UR）, controlled release nitrogen fertilizer （CR）, and controlled release nitrogen fertilizer＋urea （25%CR, 75%UR） were set up, and their impacts on maize yield, surface runoff and nitrogen loss in the growth pe- riod of maize and N2O emission were studied. The results show that maize yield, surface runoff, nitrogen loss from subsurface flow, and N2O emission in the control group was far lower than that in the fertilization treatments, revealing that fertilization was the main reason for nitrogen loss and N2O emission. Among the four treat- ments, nitrogen loss from subsurface flow in the treatment CR was the highest, up to 31.7 kg/hm^2, but N2O emission was 0.35 kg/hm^2, which was 37% less than that in the treatment UR. Nitrogen loss from subsurface flow in the treatment 25% CR was the lowest, only 20.9 kg/hm^2, and N2O emission was 15% less than that in the treatment UR. Nitrogen was slowly released from controlled release nitrogen fertilizer in the growth period, and controlled release nitrogen fertilizer could reduce N2O emis- .sion from slope cultivated land due to low content of soil inorganic nitrogen, but it could increase the nitrogen loss from subsurface flow. Therefore, the combination of controlled release fertilizer and urea can not only reduce N2O emission but also de- crease nitrogen loss from subsurface flow.

Controlled-release fertilizer(CRF): A green fertilizer for controlling non-point contamination in agriculture

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.

Effects of Film-Degraded Rice Controlled Release Fertilizer on the Nitrogen Uptake and Yield of the Hybrid Rice

Field experiment was carried out to nitrogen release characteristics of rice controlled release fertilizer (RCRF) coated with natural and half natural high molecular materials, and to thereof effects on the nitrogen uptake and yield of early and late hybrid rice from 1999 to 2000, with urea as control.In experimental fields regardless of early and late seasons, the amount of N in the plants increased exponentially at the early growth stage (y=abx) and nonlinearly at the middle and late growth stages (y=a+bx+cx2).Rice controlled release fertilizer lengthened the exponential phase and increased the parameter -b/c during the nonlinear phase. Although the N amount of plants was less in rice controlled release fertilizer plots man in urea plots within 20 days after transplanting, at the heading and maturity stages, the N amount of plants in rice controlled release fertilizer plots was above two times greater than in the urea plots due to the higher N recovery, and the high absorption density of N in the nonlinear phase.Tillers pattern and achievement of the maximum tillering stage varied with fertilizer types. The maximum tillering stage in the urea plots occurred a week earlier than in the rice controlled release fertilizer plots. Yield sink size and potential sink size of the plants reflected the N absorption pattern and the amount of N in the plants. The yields of early and late rice with 90 kg N ha-1 of rice controlled release fertilizer were respectively increased by 832.7 kg ha-1 and 412.8 kg ha-1 than those with 90 kg N ha-1 of urea, almost equivalent to the yield of early and late hybrid rice with 180 kg N ha-1 of urea.

Quantitative Evaluation on the Comprehensive Benefit of Controlled-Release Fertilizer in Typically Middle-Low Yield Rice Field

Quantitative evaluation and analysis was made to the soil nutrients,rice yield,rice and fertilizer utilization rate,and economic and ecological benefits of the slow controlled release fertilizer in typical rice fields with middle-low yield by comparing the one-time application and split applications of slow-or controlledrelease fertilizer（ CRF） with farmers fertilizer practice as the control,with the aim to explore the effect of CRF. Results showed that compared with the control,the application of CRF could meet balance nutrients required for rice growth,and the effective panicles and seed-setting rate were higher in the treatment groups of FVOL,SVOL,LADVOLwhich applied CRF. As for soil nutrients,soil pH maintained balance in FVOL,FCAI,SVOL,LADVOL. In addition,differences in soil nutrient reduction amount reached the extremely significant level between FVOLand SXNK.SVOLwhich applied CRF provided reasonable regulation of N,P and K release rate,which showed advantages over blending fertilization and farmers fertilizer practice. Comprehensive analysis found that the application of CRF could make rice tillering growth and decline leveled off,which effectively improved the quality of rice population,and it also had higher input-output ratio than that of the control and good economic benefits. In general,CRF suits to be used widely on rice crop in the regions with medium-low yield.

Migration and Transformation of Coated Controlled Release Nitrogen in Soil under Co-situs Application Mode

By using field trials, the migration and transformation of coated controlled release nitrogen （YZS80） in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out in average speed of about 0.4%/d and 32% totally in 80 d compared with common compound fertUizer. For YZS80, in the vertical downward direction of application points, urea nitrogen content increased significantly （P 〈0.05） in the 45 -80 d and the 30 -60 cm soil layers; nitrate nitrogen content was little change range and in moderate （10 -100 mg/kg） in 0 -80 d and 10 -60 cm soil layers, but increased significantly （ P 〈0.05） 45 -80 d compared to 0 -45 d; ammonium nitrogen content was significant lower （P〈0.05） before 45 d in 10 -30 cm soil layers, but significant higher（P〈0.05） after 45 d in 10 -60 cm soil layers; NO3^- -N/NH4^＋ -N meets gradually the needs of the crop with the extension of time. Under the co-situs application mode, the possibility of burning root and salt injury and loss dsk of nitrate leaching is a significant reduction.

Application of Lignin and Its Derivatives as Slow/Controlled Release Materials in Agricultural Fields

Lignin is the main by-product of pulp and papermaking and is not effectively utilized. Conversion of industrial lignins into value-added materials is beneficial for the effective utilization of resources as well as for environmental protection. Because of their adsorptivity, slow-release property,biocompatibility, and biodegradability, lignin and its derivatives find potential applications as eco-friendly slow/controlled release materials in agricultural fields. This report reviews the recent research advances in lignin-based slow/controlled release fertilizers and pesticides.

Effect of Controlled Release Nitrogen on Wheat Growth and Yield

[Objective] Effects of controlled release N fertilizers on wheat growth and yield were studied to provide reference for the application of controlled release fertilizers on wheat. [Method] A field experiment was conducted to study the effects of different types and levels of controlled release N fertilizers on the growth and yield of wheat. In this experiment, a treatment with the application of common urea and potassium chloride（common fertilizer） was established, and treatments with controlled release N fertilizers A and B with different coating materials were also established. [Result] The results showed that under the condition of the same P and K levels, controlled release N fertilizer A at a proportion of 100%, controlled release N fertilizer A at a proportion of 80% and controlled release N fertilizer B at a proportion of 80% could promote wheat growth, optimize yield components, and increase the amount of dry matter accumulation and grain yield. [Conclusion] One-time application of controlled release N fertilizer could be adopted in wheat production to achieve the purposes of saving fertilizer, saving labor and increasing efficiency.

Effects of Different Slow-release Fertilizers on Growth and Yield of Ratooning Rice

The effect of slow-release fertilizer application on reducing the fertilization times of ratooning rice was explored by carrying out plot experiments using different slow-release fertilizer formulas.The results showed that compared with conventional fertilization of farmers(TCK),there were no significant differences in plant heights of the first rice crop and ratoon rice crop and the number of tillers was slightly increased,by applying different ratios and types of slow-release fertilizers,indicating that reducing fertilization times did not affect rice growth.Compared with the TCK,the yields of treatments T1,T2,T3 and T4 of slow-release fertilizers increased to a certain extent.The yield of the first rice crop increased by 14.7%,16.7%,23.5% and 17.5%,respectively,the yields of the ratoon rice crop increased by 6.3%,5.8%,7.4% and 8.1%,respectively,and the yields of the two rice crops increased between 10.8% and 16.1%,indicating that reasonable combined application of slow-release nitrogen and fast-acting nitrogen fertilizer could meet the nutrient requirements of ratooning rice at different growth stages,and the application of slow-release fertilizers could reduce the fertilization times of ratooning rice.Based on the combination of rice yield and slow-release fertilizer cost in the first rice crop and ratoon rice crop,the T 3 formula was preferred,that is,urea-formaldehyde slow-release nitrogen fertilizer was used as the base and tillering fertilizer,and polyurethane-coated slow-release nitrogen fertilizer was used as the panicle-sprouting fertilizer.

缓控释肥硅基膜材的制备与表征

以钙镁磷肥、硅丙树脂为主要原料,加入甲基硅酸钠作粘结剂,制备了缓控释肥硅基膜材,并采用撒粉离心包衣、底喷式流化床工艺制备了密封型硅钙镁磷肥、粘结型硅钙镁磷肥、改性硅丙树脂3种包膜尿素,通过静水试验研究了此3种包膜尿素的释放特征。结果表明,3种包膜尿素的释放周期分别为60、79、96 d,在水中均能保持完整球形,耐水性较好。通过扫描电镜、红外光谱、X-射线衍射法对膜材形貌特征和结构进行表征,发现钙镁磷肥和硅丙树脂为成膜材料;甲基硅酸钠作为密封剂和防水剂参与了成膜反应,有效增加了膜材的塑性和韧性,此复合材料可用作缓控释肥的胶结剂和包膜剂。

温度敏感型缓/控释肥料的温度响应特征、养分释放性能与温敏机理研究进展

温度是影响缓/控释肥料养分释放特性的重要因素,开发温度敏感型缓/控释肥料可以使肥料养分释放与作物养分需求更加匹配,从而提高肥料利用效率,促进农业可持续发展。本文综述了聚酰胺类、聚醚类、聚酯类、多糖类以及温敏聚氨酯等常见的温敏聚合物材料的来源、类型和机理,详细阐述了聚N-异丙基丙烯酰胺(PNIPAM)、聚N-乙烯基己内酰胺(PNVCL)、环氧乙烷/环氧丙烷嵌段共聚物(EO/PO)、甲基纤维素和温敏聚氨酯等常见温敏聚合物材料用作温敏缓/控释肥料包膜材料的国内外研究进展,并评估了其在温敏缓/控释肥料中应用的可行性与优缺点。根据温敏特性,将温敏缓/控释肥料分为低临界溶解温度(LCST)响应型和结晶转变温度(Tm)/玻璃化转变温度(Tg)响应型两大类,并详细总结了这两种类型的制备方法、特征、养分释放性能以及分子作用机制。最后,指出温敏型缓/控释肥料的研发尚处于初级阶段,未来应深入开展天然高分子温敏材料的基础研究和创新,筛选绿色可生物降解温敏聚氨酯材料,研发作物和区域专用型温敏缓/控释肥料。

控释掺混肥对夏玉米氮肥利用效率和气态氮损失的影响

为阐明控释掺混肥对夏玉米产量、氮肥利用效率和气态氮损失的影响,本研究以郑单958为供试材料,设不施氮对照(CK)、常规施氮(FFP)、优化施氮(OPT)、含30%控释尿素的控释掺混肥(CRBF30)和含50%控释尿素的控释掺混肥(CRBF50)共5个处理,对比分析了不同处理的夏玉米产量、氮肥利用效率和气态氮损失(氨挥发和N2O排放)的差异。结果发现,控释掺混肥(CRBF30和CRBF50处理)较FFP处理夏玉米增产1.4%~2.9%(P>0.05),在减氮和一次性施肥的条件下实现了夏玉米稳产。与FFP处理相比,CRBF30和CRBF50处理的氮肥吸收利用率分别提高了8.4个和11.1个百分点,其中CRBF50处理差异显著(P<0.05);氮肥偏生产力分别提高了8.87 kg·kg^(-1)和9.86 kg·kg^(-1)(P<0.05)。与FFP处理相比,控释掺混肥(CRBF30和CRBF50处理)的氨挥发强度和累积氨挥发损失分别降低71.9%~73.5%(P<0.05)和71.59%~72.66%(P<0.05),N2O排放强度和累积排放量分别显著降低了34.5%~41.4%(P<0.05)和33.7%~37.5%(P<0.05)。综上,施用控释掺混肥可兼顾夏玉米稳产、氮肥高效利用并降低氮素气态损失。

袋控缓释铁肥提高梨树铁素利用率

为探究袋控缓释铁肥改善梨树缺铁黄化的效果,采用硫酸亚铁与柠檬酸混合包装,并在肥料袋中添加生根诱导调节剂6-BA,设袋控缓释铁肥(HF)、撒施铁肥(SF)和不施铁肥(CK)3个处理,分析了其对梨树细根生长状况、叶片SPAD值以及叶片活性铁含量的影响。结果表明,HF梨树根系的细根最长、根体积和根表面积最大,其中在根长和根体积指标上显著高于SF和CK(P<0.05);HF和SF两处理在生长季内细根数量显著高于CK(P<0.05);HF肥效缓慢且稳定,持续维持一定的根系生物量,延长了梨树根系的褐变时间,其中HF褐变时间最长,为54 d,其次是SF,为43 d,CK为25 d,各处理间差异显著(P<0.05);HF显著提高了根系活力(P<0.05)。HF叶片SPAD值在7月和8月显著高于SF与CK(P<0.05)。8月各处理间梨树叶片活性铁含量差异显著(P<0.05),以HF的活性铁含量最高,为27.36 mg/kg。袋控缓释铁肥有效提高了梨树铁素利用率。

不同缓/控释肥对玉米产量·经济效益及肥料利用率的影响

[目的]探究冀南平原玉米种植的缓/控释肥的应用效果。[方法]以邯玉398为材料,选取3种常见的玉米缓/控释复合肥进行田间试验,分析了不同类型缓/控释肥对玉米产量、经济效益及肥料利用率的影响。[结果]施用硫包衣缓/控释复合肥的玉米产量、利润及农学利用效率较常规复合肥分别降低1.95%、3.27%、8.27%~31.21%;施用树脂包衣缓/控释复合肥的玉米产量提高0.65%,但利润、总养分量、磷、钾偏生产力和总养分量农学利用效率分别降低了1.45%、22.59%、49.67%、49.67%、20.09%;施用脲甲醛缓/控释复合肥的玉米产量、利润及总养分量偏生产力和农学利用效率较常规复合肥分别提高5.98%、5.50%、5.99%、25.22%,且产量、利润显著提高。[结论]综合分析,脲甲醛缓/控释复合肥可作为冀南平原玉米种植中的优先推荐。

缓控释肥处理下油橄榄土壤微生物多样性特征分析

为了探究油橄榄健康施肥和实现土壤可持续化经营管理提供理论和实践依据,采用Illumina Miseq高通量测序技术对不同缓释肥处理下的油橄榄种植地0~10 cm和10~20 cm土层土壤微生物多样性及群落特征进行研究。结果显示:(1)细菌OUT隶属于35门111纲268目485科1087属;真菌OUT隶属14门42纲95目230科431属。(2)变形菌门、放线菌门、酸杆菌门、厚壁菌门、绿弯菌门和芽单胞菌门为优势细菌门,子囊菌门、担子菌门和被包霉门为优势真菌门;假单胞菌属、67-14、索利红杆菌属、Subgroup_6和红色杆菌属为优势细菌属,镰刀菌属、无茎真菌属、瓶毛壳属、小囊菌属和葡孢霉属为优势真菌属。(3)施肥处理能明显促进土壤中0~20 cm土层的真菌和0~10 cm土层的细菌生长,而抑制10~20 cm细菌生长。(4)细菌和真菌群落分布与土层相关性较小;各个处理下土壤细菌群落结构差异不明显,而真菌则存在明显差异。研究表明,施用缓控释肥能够有效增加土壤中微生物多样性,尤其是混合施肥效果更明显,6 kg半焦肥+8颗力浮丸的组合可作为生产实践中的优选参考方案。

长效氮肥施用对黑土水旱田CH_4和N_2O排放的影响

通过在黑土玉米地与水稻田施用长效氮肥后发现 ,长效碳酸氢铵 (长碳 )与长效尿素(长尿 )能显著减少黑土玉米地N2 O的排放。与施用普通尿素相比 ,其排放量分别减少了5 9 2 %和 73 3%。长碳和长尿还能促进黑土玉米地对CH4的吸收作用。黑土水稻田施用长尿后 ,N2 O的排放减少了 6 1%。