稻田以水带氮肥（尿素）深施技术研究

本研究将稻田氮肥施用方法与水分管理结合起来。施肥前对稻田停止灌水晾田数天,尽可能控制土壤处于水不饱和状态,再把氮肥表施,然后立即浅层灌水,让氮肥随水下渗带入土层中,达到氮肥深施的目的,简称为“以水带氮肥深施技术”。研究结果表明,此技术可将表施的60%以上的尿素氮带入土层中,减少了肥料氮素的损失,提高了氮肥的增产效果和氮素利用率,对水稻省肥增产的作用十分显著,可作为氮肥经济合理施用技术之一,在具有排灌条件的稻田中推广应用。     

半腐解秸秆覆盖下旱作水稻对15N的吸收和分配

 在模拟田间条件下的水泥池（微区）内，用半腐解秸秆覆盖旱作水稻，两个水平的15N标记尿素分别作基肥、分蘖肥和穗肥施用，研究了不同时期施用的15N在水稻各部位的分配、15N的利用率和土壤 植株系统的氮素平衡。结果表明植株氮素含量中来自肥料氮的百分比（Ndff%）、水稻对15N的吸收和利用率以及15N的土壤残留率因标记肥料的施用时期和用量的不同而有很大差异。分蘖肥的15N在水稻各部位中的Ndff%最高，而作为基肥施入的15N在水稻体内的Ndff%最低。植株对氮肥利用率的最低和最高值分别为5.58%和51.53%，氮肥的土壤残留率最低和最高值分别为13.81%和29.87%。     

尿素和缓释肥混配深施对水稻产量和生理特性的影响

研究了不同比例尿素和缓释肥深施对水稻产量和生理特性的影响,旨在探明深施肥条件下促进水稻生长的尿素和缓释肥的最佳比例。试验以杂交水稻青香优19香和常规水稻象牙香占为材料,设置4个不同处理,分别是：T1,尿素和缓释肥按1∶1(按含氮量计,下同)混合,全部作基肥一次性深施入土壤,施肥深度6 cm;T2,尿素和缓释肥按1∶2混合,全部作基肥一次性深施入土壤;T3,尿素和缓释肥按2∶1混合,全部作基肥一次性深施入土壤;T4,水稻整个生育期均不施肥。所有施肥处理氮肥(纯N)用量均为150 kg/hm²。结果表明,青香优19香T2处理产量比T1、T3和T4处理分别显著增加29.47%、43.49%和73.56%;相比其他处理,T2处理的青香优19香和象牙香占叶面积指数、干物质积累量,以及叶片硝酸还原酶(NR)、过氧化物酶(POD)和过氧化氢酶(CAT)活性明显提高,但丙二醛(MDA)含量明显下降。说明尿素和缓释肥按照1∶2比例深施是一种较好的施肥方法。     

用15N示踪研究不同氮水平下剑麻的氮素吸收利用特性

采用盆栽试验和15N示踪技术,研究4个不同氮（N）水平对剑麻生长及氮素吸收利用特性的影响。结果表明,施氮显著提高剑麻株高、叶长、叶宽和根粗。施氮处理地上部鲜重、含水量、全氮含量和吸氮量均有所增加,但施氮处理之间差异不显著。剑麻地上部和根系吸收的肥料N随着氮水平增加而增加,各处理整株肥料N比例,以示踪法计算为24.2％~32.6％,差减法计算为34.6％~53.1％。不同氮水平下剑麻氮素利用率变化不明显,整株氮素利用率,示踪法计算为20.0％~22.0％,差减法计算为30.0％~35.7％。可见,剑麻吸收的肥料氮低于土壤氮;剑麻的氮素利用率偏低;以示踪法求得的肥料N比例和氮素利用率均低于以差减法求得的结果。     

水稻抽穗灌浆后喷施尿素对茎叶及籽粒氮素吸收的影响

八五〇农场进行尿素叶面喷施试验,结果表明:水稻在抽穗灌浆后喷施尿素10 d内,茎叶内氮素能够保持较高的水平;随着氮素喷施量的增加,籽粒氮素积累越快,同时茎叶氮素减少越缓慢,成熟期氮素含量越高。试验推荐喷施用量为150～200 g/667 m~2。     

新型高效尿素在水稻上的施用效果

为探讨高效尿素在水稻上的施用效果,通过田间试验,研究新型高效尿素对水稻产量、农艺性状及氮肥利用率的影响,试验结果表明,高效尿素的氮肥利用率显著高于常规尿素,施60％常规用量的高效尿素、50％常规用量的高效尿素的氮肥农学利用率和吸收利用率分别比施常规用量的常规尿素处理提高5．09kg稻谷／kgN、6．04kg稻谷／kgN和14．79％、22．41％。60％常规用量的高效尿素处理水稻产量与当年正常产量不存在显著差异,仅比正常产量少86kg／hm2,50％常规用量的高效尿素处理水稻产量显著低于当年正常产量。高效尿素对水稻农艺性状也有一定影响,高效尿素处理的水稻穗下节间显著长于常规尿素处理,生长更为健壮。     

不同肥料结构对棉田氮素去向的研究

在等氮、磷、钾条件下,应用^15N示黥的方法研究了盆栽条件下不同肥料结构对棉花的生物学效应度氮素去向的影响。所得主要蛄果如下：（1）与单施化肥相比,绿肥＋沼肥＋化肥配施有利于氮向生殖器官转移,增产效果较好,绿肥＋化肥配施效果次之。（2）有机无机肥配施吸收的土壤氮和肥料氮明显大于单施化肥。棉株生育前期对土壤氮的依赖性较高。后期对肥料氮的依赖性较高,不同时期施氮对各器官的贡献率也说明重施化肥作花铃肥的重要性。（3）有机无机肥配施肥料氯在土壤中的残留量为单施化肥的1．48-1．67和3．12-3．52倍。而损失量后者为前者的1．18-1．24和2．51-2．62倍,其生态效益十分明显。     

新型高效绿色氮肥管理对水稻产量形成与氮素利用及氨挥发损失的影响

通过大田试验采用随机区组设计,设置7种施氮处理,即不施氮肥(CK)、农民常规施肥(FFP)、脲酶抑制剂型氮肥并减氮21.40%(与FFP比,余同)(OPT)、一次性机械侧深施树脂包膜尿素并减氮35.70%(CRUM1)、一次性机械侧深施肥包肥并减氮35.70%(CRUM2)、一次性穴施树脂包膜尿素并减氮51.80%(CRUR1)、一次性穴施肥包肥并减氮51.80%(CRUR2),测定不同施氮处理下水稻株高、分蘖、干物质量、产量、氮素利用效率以及氨挥发损失等,以探究新型氮肥管理方式对水稻产量、氮素利用效率和氮挥发损失的影响。结果表明,CRUM1和CRUM2处理株高和分蘖数与FFP处理相当;与传统撒施(CK、FFP和OPT,下同)相比,CRUM1和CRUM2干物质积累量提高11.90%～12.30%;根据水稻氮素营养指数(NNI),机械侧深施氮能满足水稻生长对氮素的需求。水稻侧深施和穴施在减氮35.70%～51.80%的情况下也可高产稳产(9.76 t/hm²和9.60 t/hm²)。与传统撒施相比,机械侧深施和穴施的田面水NH4+-N较低,氨挥...     

控失尿素与普通尿素配施对水稻产量及氮肥利用效率的影响

为探讨控失尿素与普通尿素配施在海南省水稻上的应用效果,通过 2016 年和 2017 年两季田间试验,采用随 机区组设计,以不施氮肥处理作为对照（CK）,设置常规尿素（CU）与控失尿素（CLU）不同配施比例,在等氮量条 件下,设 100% CU、70% CU+30% CLU、50% CU+50% CLU、30% CU+70% CLU 和 100% CLU 5 个处理,分析水稻叶 绿素含量、稻谷产量及其构成因子、氮吸收累积量、氮肥利用效率以及经济效益等指标。结果显示,施氮显著增加稻 谷产量,与 CK 相比,增幅为 67.2%~82.0%（2016 年）和 36.7%~46.7%（2017 年）。30% CU+70% CLU 的稻谷产量和 有效穗均显著高于 100% CU 处理,产量增幅为 8.8%（2016 年）和 7.3%（2017 年）,有效穗数增幅为 14.2%（2016 年） 和 12.0%（2017 年）。随着 CLU 所占比例的提高,水稻地上部氮吸收累积量、氮肥回收利用率和农学利用率均呈增加 趋势。与 100% CU 处理相比,其余控失尿素处理的氮肥回收利用率增幅为 12.3%~18.4%（2016 年）和 12.7%~17.7%（2017 年）,氮肥农学利用率增幅为 20.8%~21.9%（2016 年）和 16.8%~23.5%（2017 年）。随着 CLU 所占比例的提高,水稻 总产值和相对净收益呈先增加后降低的趋势,30% CU+70% CLU 处理达到最大。综上所述,在本试验条件下,30% CU+70% CLU 能够获得较高的稻谷产量、氮肥利用效率及经济效益,其可作为该地区氮肥施用的推荐比例。     

控释尿素减施对双季稻田氨挥发损失和氮肥利用率的影响

【目的】研究连续控释尿素减施对双季稻籽粒产量、N肥利用率和NH₃挥发损失的影响,以期为水稻稳产条件下减少双季稻田氮素损失提供理论依据和技术方法。【方法】以中早39（早稻）和泰优390（晚稻）为材料,设置不同控释尿素N用量的等N量控释尿素(CRU₁)、控释尿素减N 10%(CRU₂)、控释尿素减N 20%(CRU₃)、控释尿素减N 30%(CRU₄)以及尿素(U)和不施肥对照(CK)的6个处理,采用密闭室间歇通气法监测双季稻田NH₃挥发特征,同时测定水稻产量和N含量。【结果】普通尿素(U)处理和控释尿素(CRU)处理施基肥和分蘖肥后早稻NH₃挥发发生在施肥后的8~9 d内,峰值分别于第1~2天和第2~4天出现;晚稻NH₃挥发发生在施肥后的6~7 d内,峰值分别于第2~3 天和第3~4 天出现。早、晚稻生长季U处理总计NH₃挥发损失量(率)最高,分别为47.2 kg/hm² (26.4%)和61.9 kg/hm²(28.7%),产量分别为5.5 t/hm²和6.2 t/hm²,N肥利用率分别为23.0%和20.0%;早、晚稻生长季CRU处理总计NH₃挥发损失量(率)分别为22.8~32.3 kg/hm²(14.6%~16.5%)和30.4~42.1 kg/hm²(15.9%~17.6%),产量分别为5.8~6.3 t/hm²和6.6~7.5 t/hm²,N肥利用率分别为34.3%~40.5%和33.8%~39.2%;其中,CRU₂处理在早、晚稻生长季总计NH₃挥发损失量较U处理降低40.9%、38.3%,产量增加14.9%、20.9%,N肥利用率提高75.6%、96.0%。早、晚稻生长季及双季稻整个生长季CRU处理总计NH₃挥发损失量及籽粒产量与施N量呈显著线性关系。【结论】施用控释尿素显著减少双季稻田NH₃挥发损失,增加籽粒产量,提高N肥利用率,以减N 10%处理效果最明显。     

Characterization of Nitrogen Uptake Pattern in Malaysian Rice MR219 at Different Growth Stages Using ~(15)N Isotope

Nitrogen(N) use efficiency is usually less than 50%, and it remains a major problem in rice cultivation. Controlled release fertilizer(CRF) technology is one of the well-known efforts to overcome this problem. The efficiency of CRF, however, is very much dependent on the timing of nutrient release. This study was conducted to determine the precise time of N uptake by rice as a guideline to develop efficient CRF. Fertilizer N uptake by rice at different growth stages was investigated by using 15 N isotopic technique. Rice was planted in pots, with 15 N urea as N source at the rate of 120 kg/hm2. Potassium and phosphorus were applied at the same rate of 50 kg/hm2. Standard agronomic practices were employed throughout the growing periods. Rice plants were harvested every two weeks until maturation at the 14 th week and analyzed for total N and 15 N content. Nitrogen derived from fertilizer was calculated. Total N uptake in plants consistently increased until the 11 th week. After that, it started to plateau and finally declined. Moreover, N utilization by rice plants peaked at 50%, which occurred during the 11 th week after transplanting. N derived from fertilizer in rice plants were in the range of 18.7% to 40.0% in all plant tissues. The remaining N was derived from soil. Based on this study, N release from CRF should complete by the 11 th week after planting to ensure the maximum fertilizer N uptake by rice plants. Efficient CRF should contribute to higher N derived from fertilizer which also resulted in a higher total N uptake by rice plants, increasing the potential of rice to produce higher yield while at the same time of reducing loss.     

Rice Uptake and Recovery of Nitrogen with Different Methods of Applying 15N-Labeled Chicken Manure and Ammonium Sulfate

Abstract

The effects of different methods of fertilization on rice uptake and recovery of nitrogen were studied using ¹⁵N-lablled chicken manure (CM) and ammonium sulfate (AS). The results showed that the application method of totally basal dressing of organic and inorganic fertilizers can increase the N uptake by rice from the fertilizers. The N uptake from CM was obviously higher than that from AS. The N partitioning to rice grain was also higher than other application methods. The effect on increasing yield was obviously higher than the method of application of chemical fertilizers only. This method had such benefits as increasing N use efficiency, increasing N residue in soil and reducing N loss. High rice yield can be obtained while the soil fertility can be maintained with this method. So it is an effective and practical method of fertilization technique thus can be recommended to rice growers.     

应用15N示踪技术研究橡胶树幼苗对不同氮肥的吸收和分配

采用15N示踪技术研究橡胶树幼苗对尿素、硫酸铵、硝酸钙及硝酸铵等4种氮肥的吸收和分配特征。结果表明：施用尿素、硫酸铵的胶苗生长要显著优于硝酸钙;各器官对4种氮肥的吸收和分配并不一致;器官中15N丰度大致以形成层最高,叶片、粗根和叶柄最低;15N示踪下4种氮肥利用率介于18.04％～19.03％,但差异不显著;4种氮肥的表观利用率以尿素和硫酸铵处理的最高,分别为20.18％和19.53％,硝酸钙处理的最低,仅有9.25％。综上所述,盆栽试验条件下酰胺态和铵态氮肥的表观利用率要优于硝态氮肥。     

应用15N尿素研究氮素在幼龄橡胶树中吸收和分配特性

通过同位素示踪技术研究了不同时期幼龄橡胶树对15N标记尿素的吸收和分配特性。结果表明:顶蓬嫩叶和成熟叶从氮肥中吸收分配到的15N的量,对该器官全氮量的贡献率(Ndff值),随着施肥时间的延长总体均呈增加趋势;同一采样时间里顶蓬嫩叶Ndff值均大于成熟叶。落叶前后氮素在橡胶树各器官中分配差异显著。落叶前期橡胶树吸收的氮素主要分配在叶片中;落叶期橡胶树吸收的氮素则主要分配在主茎中。     

水稻精确施氮试验研究

对水稻进行施氮试验、示范研究,结果表明,水稻精确施氮技术具有节省氮肥,提高氮肥利用率,增加单产,减少污染,保护土壤环境的重要作用。通过试验可知,精确施肥较常规施肥可节省氮肥4.9 kg/667 m2,增产稻谷30 kg/667 m2以上,可提高氮肥利用率6.5%。     

Soil Nitrogen Distribution and Plant Nitrogen Utilization in Direct-Seeded Rice in Response to Deep Placement of Basal Fertilizer-Nitrogen

Deep placement of controlled-release fertilizer increases nitrogen(N) use efficiency in rice planting but is expensive. Few studies on direct-seeded rice have examined the effects of deep placement of conventional fertilizer. With prilled urea serving as N fertilizer, a two-year field experiment with two N rates(120 and 195 kg/hm~2) and four basal N application treatments(B50, all fertilizer was broadcast with 50% as basal N; D50, D70 and D100 corresponded to 50%, 70% and 100% of N deeply placed as basal N, respectively) were conducted in direct-seeded rice in 2013 and 2014. Soil N distribution and plant N uptake were analyzed. The results showed that deep placement of basal N significantly increased total N concentrations in soil. Significantly greater soil N concentrations were observed in D100 compared with B50 at 0, 6 and 12 cm(lateral distance) from the fertilizer application point both at mid-tillering and heading stages. D100 presented the highest values of dry matter and N accumulation from seeding to mid-tillering stages, but it presented the lowest values from heading to maturity stages and the lowest grain yield for no sufficient N supply at the reproductive stage. The grain yield of D50 was the highest, however, no significant difference was observed in grain yield, N agronomic efficiency or N recovery efficiency between D70 and D50, or between D70 and B50, while D70 was more labor saving than D50 for only one topdressing was applied in D70 compared with twice in other treatments. The above results indicated that 70% of fertilizer-N deeply placed as a basal fertilizer and 30% of fertilizer-N topdressed as a panicle fertilizer constituted an ideal approach for direct-seeded rice. This recommendation was further verified through on-farm demonstration experiments in 2015, in which D70 produced in similar grain yields as B50 did.     

利用15N标记确定氮素营养水平对大豆籽粒氮素构成的影响

以东农47为试材,采用15N标记的(NH4)2SO4为氮源,利用砂培方式研究了氮素营养水平对大豆籽粒氮素构成和产量的影响.结果表明:随外源氮水平增加,大豆产量呈先增加后降低的变化趋势,营养液中氮为50 mg·L-1时产量最高;前期高氮后期低氮处理时,随高氮处理的时间延长产量降低;于R4或R5期提高外源氮水平可以增加大豆...     

Effect of a Bio-decomposer on Utilization by Rice (Oryza sativa L.) of 15N Derived from Rice Chaff or Straw

Abstract

The ¹⁵N - labeled technique was used to study the stock, transformation, fate and utilization efficiency of N in the farming–pig husbandry–biogas ecosystem in rice areas. It was shown that the crude protein digestibility of the ensilaged milk vetch by pig was 53.76%, the recovery rates of ensilaged milk vetch N from the pig feces and urine were 39.36% and 24.71%, respectively. The recovery rate of biogas fermentation N of pig feces and urine was 97.9%. The quantity of alkali-hydrolysable N was 2.6 times as great as before the fermentation. The mixed application of milk vetch, biogas-tank sludge and chemical fertilizer could promote N partitioning to rice grain, therefore it was advantageous to yield improvement. The residual quantity in soil of the fertilizer N was equivalent to 2.0 - 2.5 times that of only chemical fertilizer and yet gaseous loss N of the latter was 2.6-8.2 times that of the former. The comprehensive economic effect of the whole ecosystem increased by times, compared with the only milk vetch-early rice-late rice pattern, and ecological effect and social effect were also very prominent.     

Improvement of nitrogen management in rice paddy fields using chlorophyll meter (SPAD)

Optimum rate and timing application of nitrogen (N) fertilizer are most crucial in achieving high yield in irrigated lowland rice. In order to assess leaf N status, a semidwarf rice cultivar (Khazar) was grown with different N application treatments (0, 40, 80, and 120 kg N ha⁻¹ splited at transplanting, midtillering, and panicle initiation stages) in a sandy soil in Guilan Province, Iran, in 2003. The chlorophyll meter (SPAD 502) readings were recorded and leaf N concentrations were measured on the uppermost fully expanded leaf in rice plants at 10-day internals from 19 days after transplanting to grain maturity. Regression analysis showed that the SPAD readings predicted only 23% of changes in the leaf N concentration based on pooled data of leaf dry weight (N _dw) for all growth stages. However, adjusting the SPAD readings for specific leaf weight (SPAD/SLW) improved the estimation of N _dw, up to 88%. Specific leaf weight (SLW), SPAD readings, leaf area and weight as independent variables in a multiple regression analysis predicted 96% of the N _dw changes, while SPAD readings independently predicted about 80% of leaf N concentration changes on the basis of leaf area (N _a). It seems that chlorophyll meter provides a simple, rapid, and nondestructive method to estimate the leaf N concentration based on leaf area, and could be reliably exploited to predict the exact N fertilizer topdressing in rice.